Sample records for crystal display efficiency

  1. Liquid crystal panel for high efficiency barrier type autostereoscopic three-dimensional displays. (United States)

    Chen, Cheng-Huan; Huang, Yi-Pai; Chuang, Shang-Chih; Wu, Chi-Lin; Shieh, Han-Ping D; Mphepö, Wallen; Hsieh, Chiu-Ting; Hsu, Shih-Chia


    An autostereoscopic display with parallax barrier attached onto a liquid crystal panel suffers from the trade-off between brightness and crosstalk. One approach for making improvement by modifying the layout of light blocking components, such as thin film transistor, storage capacitor, and protrusion, in the liquid crystal pixel has been proposed. Ray tracing simulation shows that the aperture of the slanted barrier can be significantly increased, hence increasing efficiency, while keeping the same crosstalk level if those light blocking components can be shifted to the corner of the pixel. A six-view 2.83 in. (7.19 cm) prototype has shown improvement on both brightness and crosstalk compared to its counterpart using a traditional liquid crystal panel, which demonstrates an effective approach for a high-efficiency barrier-type autostereoscopic 3D display with a liquid crystal panel.

  2. Liquid Crystal Airborne Display (United States)


    81/2X 11- 10 -9 .8 display using a large advertising alphanimeric ( TCI ) has been added to the front of the optical box used in the F-4 aircraft for over a wide range of tempera - tures, including normal room temperature. What are Liquid Crystals? Liquid crystals have been classified in three...natic fanctions and to present data needed for the semi- automatic and manual control of system functions. Existing aircraft using CRT display

  3. Crystal ball single event display

    Energy Technology Data Exchange (ETDEWEB)

    Grosnick, D.; Gibson, A. [Valparaiso Univ., IN (United States). Dept. of Physics and Astronomy; Allgower, C. [Argonne National Lab., IL (United States). High Energy Physics Div.; Alyea, J. [Valparaiso Univ., IN (United States). Dept. of Physics and Astronomy]|[Argonne National Lab., IL (United States). High Energy Physics Div.


    The Single Event Display (SED) is a routine that is designed to provide information graphically about a triggered event within the Crystal Ball. The SED is written entirely in FORTRAN and uses the CERN-based HICZ graphing package. The primary display shows the amount of energy deposited in each of the NaI crystals on a Mercator-like projection of the crystals. Ten different shades and colors correspond to varying amounts of energy deposited within a crystal. Information about energy clusters is displayed on the crystal map by outlining in red the thirteen (or twelve) crystals contained within a cluster and assigning each cluster a number. Additional information about energy clusters is provided in a series of boxes containing useful data about the energy distribution among the crystals within the cluster. Other information shown on the event display include the event trigger type and data about {pi}{sup o}`s and {eta}`s formed from pairs of clusters as found by the analyzer. A description of the major features is given, along with some information on how to install the SED into the analyzer.

  4. Displaying gray shades in liquid crystal displays

    Indian Academy of Sciences (India)

    T N Ruckmongathan


    Quality of image in a display depends on the contrast, colour, resolution and the number of gray shades. A large number of gray shades is necessary to display images without any contour lines. These contours are due to limited number of gray shades in the display causing abrupt changes in grayness of the image, while the original image has a gradual change in brightness. Amplitude modulation has the capability to display a large number of gray shades with minimum number of time intervals [1,2]. This paper will cover the underlying principle of amplitude modulation, some variants and its extension to multi-line addressing. Other techniques for displaying gray shades in passive matrix displays are reviewed for the sake of comparison.

  5. Liquid crystal displays for aircraft engineering

    Directory of Open Access Journals (Sweden)

    Kovalenko L. F.


    Full Text Available Operating conditions for liquid-crystal displays of aircraft instruments have been examined. Requirements to engineering of a liquid-crystal display for operation in severe environment have been formulated. The implementation options for liquid-crystal matrix illumination have been analyzed in order to ensure the sufficient brightness depending on external illumination of a display screen.

  6. Emerging Technologies of Liquid Crystal Displays

    Institute of Scientific and Technical Information of China (English)

    Sin-Doo Lee; Chang-Jae Yu; Jae-Hong Park; Min-Sik Jung


    The general features and the emerging technologies of liquid crystal displays are described from the viewpoints of wide viewing and fast response technologies. The device applications of liquid crystals for optical communications are also described.

  7. Characterising laser beams with liquid crystal displays (United States)

    Dudley, Angela; Naidoo, Darryl; Forbes, Andrew


    We show how one can determine the various properties of light, from the modal content of laser beams to decoding the information stored in optical fields carrying orbital angular momentum, by performing a modal decomposition. Although the modal decomposition of light has been known for a long time, applied mostly to pattern recognition, we illustrate how this technique can be implemented with the use of liquid-crystal displays. We show experimentally how liquid crystal displays can be used to infer the intensity, phase, wavefront, Poynting vector, and orbital angular momentum density of unknown optical fields. This measurement technique makes use of a single spatial light modulator (liquid crystal display), a Fourier transforming lens and detector (CCD or photo-diode). Such a diagnostic tool is extremely relevant to the real-time analysis of solid-state and fibre laser systems as well as mode division multiplexing as an emerging technology in optical communication.

  8. Supramolecular liquid crystal displays : construction and applications

    NARCIS (Netherlands)

    Hoogboom, Joannes Theodorus Valentinus


    This thesis describes chemical methodologies, which can be ued to construct alignment layers for liquid crystal display purposes in a non-clean room environment, by making use of supramolecular chemistry. These techniques are subsequently used to attain control over LCD-properties, both pre- and pos

  9. Liquid Crystal Microlenses for Autostereoscopic Displays

    Directory of Open Access Journals (Sweden)

    José Francisco Algorri


    Full Text Available Three-dimensional vision has acquired great importance in the audiovisual industry in the past ten years. Despite this, the first generation of autostereoscopic displays failed to generate enough consumer excitement. Some reasons are little 3D content and performance issues. For this reason, an exponential increase in three-dimensional vision research has occurred in the last few years. In this review, a study of the historical impact of the most important technologies has been performed. This study is carried out in terms of research manuscripts per year. The results reveal that research on spatial multiplexing technique is increasing considerably and today is the most studied. For this reason, the state of the art of this technique is presented. The use of microlenses seems to be the most successful method to obtain autostereoscopic vision. When they are fabricated with liquid crystal materials, extended capabilities are produced. Among the numerous techniques for manufacturing liquid crystal microlenses, this review covers the most viable designs for its use in autostereoscopic displays. For this reason, some of the most important topologies and their relation with autostereoscopic displays are presented. Finally, the challenges in some recent applications, such as portable devices, and the future of three-dimensional displays based on liquid crystal microlenses are outlined.

  10. Latest Developments In Liquid Crystal Television Displays (United States)

    Morozumi, Shinji; Oguchi, Kouichi; Ohshima, Hiroyuki


    This paper will discuss developments in liquid crystal (LC) television displays, mainly for pocket-size TV sets. There are two types of LC television displays. One is a simple multiplexing type, and the other is an active matrix type. The former type is an easier way to fabricate large and low-cost LC panels than the latter. However, it has serious drawbacks. The contrast gets lower as the duty ratio gets higher. Therefore the TV image of this type inevitably has rather low contrast and resolution. On the other hand, the active matrix type, which consists of active elements in each pixel, has several advantages in overcoming such problems. The metal oxide semiconductor transistors and the amorphous or polycrystalline Si thin-film transistors (TFTs) have possibilities in this application. A full-color LC display, which can be realized by the combina-tion of color filters and poly Si TFT arrays on a transparent substrate, was proven to have excellent color image, close to that of conventional CRTs. Here, several examples of LC television displays, including color, are shown. Some of them are already on the market, and others will be soon.

  11. Thermal modeling of laser-addressed liquid-crystal displays (United States)

    Evans, K. E.; Nkansah, M. A.


    Optical-absorption calculations and finite-element methods are used to calculate time-dependent temperature profiles in two contrasting laser-addressed liquid-crystal displays. It is shown that the presence of conducting electrode layers has a significant effect on the temperature profiles both by affecting the optical-absorption characteristics of the cell and the resulting thermal conductivity. It is shown that efficient optical absorption does not necessarily result in the best cell-addressing performance.

  12. Recovery of valuable materials from waste liquid crystal display panel. (United States)

    Li, Jinhui; Gao, Song; Duan, Huabo; Liu, Lili


    Associated with the rapid development of the information and electronic industry, liquid crystal displays (LCDs) have been increasingly sold as displays. However, during the discarding at their end-of-life stage, significant environmental hazards, impacts on health and a loss of resources may occur, if the scraps are not managed in an appropriate way. In order to improve the efficiency of the recovery of valuable materials from waste LCDs panel in an environmentally sound manner, this study presents a combined recycling technology process on the basis of manual dismantling and chemical treatment of LCDs. Three key processes of this technology have been studied, including the separation of LCD polarizing film by thermal shock method the removal of liquid crystals between the glass substrates by the ultrasonic cleaning, and the recovery of indium metal from glass by dissolution. The results show that valuable materials (e.g. indium) and harmful substances (e.g. liquid crystals) could be efficiently recovered or separated through above-mentioned combined technology. The optimal conditions are: (1) the peak temperature of thermal shock to separate polarizing film, ranges from 230 to 240 degrees C, where pyrolysis could be avoided; (2) the ultrasonic-assisted cleaning was most efficient at a frequency of 40 KHz (P = 40 W) and the exposure of the substrate to industrial detergents for 10 min; and (3) indium separation from glass in a mix of concentrated hydrochloric acid at 38% and nitric acid at 69% (HCl:HNO(3):H(2)O = 45:5:50, volume ratio). The indium separation process was conducted with an exposure time of 30 min at a constant temperature of 60 degrees C.

  13. Liquid crystals beyond displays chemistry, physics, and applications

    CERN Document Server

    Li, Quan


    The chemistry, physics, and applications of liquid crystals beyond LCDs Liquid Crystals (LCs) combine order and mobility on a molecular and supramolecular level. But while these remarkable states of matter are most commonly associated with visual display technologies, they have important applications for a variety of other fields as well. Liquid Crystals Beyond Displays: Chemistry, Physics, and Applications considers these, bringing together cutting-edge research from some of the most promising areas of LC science. Featuring contributions from respected researchers from around the globe, th

  14. High Performance Negative Dielectric Anisotropy Liquid Crystals for Display Applications

    Directory of Open Access Journals (Sweden)

    Xiaolong Song


    Full Text Available We review recent progress in the development of high birefringence (Δn ≥ 0.12 negative dielectric anisotropy (Δε < 0 liquid crystals (LCs for direct-view and projection displays. For mobile displays, our UCF-N2 (low viscosity, negative Δε, high Δn based homogeneous alignment fringe-field switching (called n-FFS mode exhibits superior performance to p-FFS in transmittance, single gamma curve, cell gap insensitivity, and negligible flexoelectric effect. For projection displays using a vertical alignment liquid-crystal-on-silicon (VA LCOS, our high birefringence UCF-N3 mixture enables a submillisecond gray-to-gray response time, which is essential for color sequential displays without noticeable color breakup. Our low viscosity UCF-N2 also enables multi-domain VA displays to use a thinner cell gap for achieving faster response time.

  15. Super high precision 200 ppi liquid crystal display series; Chokoseido 200 ppi ekisho display series

    Energy Technology Data Exchange (ETDEWEB)



    In mobile equipment, in demand is a high precision liquid crystal display (LCD) having the power of expression equivalent to printed materials like magazines because of the necessity of displaying a large amount of information on a easily potable small screen. In addition, with the spread and high-quality image of digital still cameras, it is strongly desired to display photographed digital image data in high quality. Toshiba Corp., by low temperature polysilicone (p-Si) technology, commercialized the liquid crystal display series of 200 ppi (pixels per inch) precision dealing with the rise of the high-precision high-image quality LCD market. The super high precision of 200 ppi enables the display of smooth beautiful animation comparable to printed sheets of magazines and photographs. The display series are suitable for the display of various information services such as electronic books and electronic photo-viewers including internet. The screen sizes lined up are No. 4 type VGA (640x480 pixels) of a small pocket notebook size and No. 6.3 type XGA (1,024x768 pixels) of a paperback size, with a larger screen to be furthered. (translated by NEDO)

  16. Liquid crystal displays with high brightness of visualization versus active displays (United States)

    Olifierczuk, Marek; Zieliński, Jerzy


    Nowadays Liquid Crystal Displays (LCD) takes the very important place among different visualization devices. It's are used in many standard applications such as computer or video screens. In May 2006, 100" LCD TV monitor had been shown by LG. But beside of this main direction of display development, very interesting - because of insignificant electro-magnetic disturbances - is the possibility of it's applications in motorization and aviation. An example of it can be a glass cockpit of U2 , Boeing 777 or many different car dashboards. On this field beside LCD we have now many another display technologies, but interesting for us are 3 of them: FEDs (Field Emission Displays), OLEDs (Organic Light Emitting Diode), PLEDs (Polymer Light Emitting Diode). The leading position of LCD is a result of LCD unique advantages of flat form, weight, power consumption, and reliability, higher (than CRT) luminance, luminance uniformity, sunlight readability, wide dimming range, fault tolerance and a large active display area with a small border. The basis of starting our investigation was the comparison of passive LCD and the other technology, which can be theoretically used on motorization and aviation field. The following parameters are compared: contrast ratio, luminance level, temperature stability, life-time, operating temperature range, color performance, and depth, viewing cone, technology maturity, availability and cost. In our work an analysis of Liquid Crystal Displays used in specific applications is done. The possibilities of the applications such a display under high lighting level are presented. The presented results of this analysis are obtained from computer program worked by authors, which makes it possible to calculate the optical parameters of transmissive and reflective LCD working in quasi-real conditions. The base assumption of this program are shown. This program calculate the transmission and reflection coefficient of a display taking into account the

  17. Green backlighting for TV liquid crystal display using carbon nanotubes (United States)

    Delepierre, Gabriel; Mahfouz, Rami; Cadete Santos Aires, Francisco J.; Dijon, Jean


    A methodology to evaluate the emission characteristics of carbon nanotube layers in the context of liquid crystal display backlighting has been elaborated. Carbon nanotube layers with emission characteristics compatible with backlighting have been demonstrated for growth temperature as low as 400 °C, thanks to the use of plasma pretreatment before growth. This very low growth temperature allows to use soda lime glass for the backlight unit and thus to expect very low cost and very low power consumption devices with this technology.

  18. Averaged Stokes polarimetry applied to characterize parallel-aligned liquid crystal on silicon displays


    Márquez Ruiz, Andrés; Martínez Guardiola, Francisco Javier; Gallego Rico, Sergi; Ortuño Sánchez, Manuel; Beléndez Vázquez, Augusto; Pascual Villalobos, Inmaculada


    Parallel-aligned liquid crystal on silicon (PA-LCoS) displays have become the most attractive spatial light modulator device for a wide range of applications, due to their superior resolution and light efficiency, added to their phase-only capability. Proper characterization of their linear retardance and phase flicker instabilities is a must to obtain an enhanced application of PA-LCoS. We present a novel polarimetric method, based on Stokes polarimetry, we have recently proposed for the mea...

  19. Fast-response liquid crystal display by the VA-IPS display mode with nematic liquid crystal and polymer networks (United States)

    Chen, Tien-Jung; Lin, Guan-Jhong; Chen, Bo-Yu; Wu, Jin-Jei; Yang, Ying-Jay


    To improve electrooptical characteristics of the vertical aligned (VA) liquid crystal displays (LCDs), the monomer material and in-plane switching (IPS) field produced by interdigital electrodes are employed in LC cells. The fast switching response and well optical transmittance of the VA-IPS display mode are successfully achieved by mixing the nematic LC with polymer networks, attributed to the surface anchoring, and the molecular orientation of the LC cell will be further governed, especially under the greater applied voltage. Furthermore, the high concentration doping of the monomer can effectively improve the response behavior, but it also results in the transmittance sacrificed due to the light scattering, and the threshold voltage (Vth) increased.

  20. Vacuum pyrolysis characteristics and kinetic analysis of liquid crystal from scrap liquid crystal display panels. (United States)

    Chen, Ya; Zhang, Lingen; Xu, Zhenming


    Recycling of waste liquid crystal display (LCD) panels is an urgent task with the rapid expanding LCD market. However, as important composition of LCD panels, the treatment of liquid crystal is seldom concerned for its low concentration. In present study, a stripping product enriched liquid crystal and indium is gained by mechanical stripping process, in which liquid crystal is enriched from 0.3wt.% to 53wt.% and indium is enriched from 0.02wt.% to 7.95wt.%. For the stripping product, liquid crystal should be removed before indium recovery because (a) liquid crystal will hinder indium recycling; (b) liquid crystal is hazardous waste. Hence, an effective and green approach by vacuum pyrolysis is proposed to treat liquid crystal in the stripping product. The results are summarized as: (i) From the perspective of apparent activation energy, the advantages of vacuum pyrolysis is expounded according to kinetic analysis. (ii) 89.10wt.% of liquid crystal is converted and the content of indium in residue reaches 14.18wt.% under 773K, 15min and system pressure of 20Pa. This study provides reliable information for further industrial application and an essential pretreatment for the next step of indium recycling.

  1. The study of LED uniform lightguide for liquid crystal display backlight applications (United States)

    Chien, Chao-Heng; Chen, Zhi-Peng


    A conventional backlight unit (BLU) is used to as the light module to present uniform light of liquid crystal display (LCD). In general, cold cathode fluorescent lamp (CCFL) is utilized to be the light source of BLU. The light emitting diode (LED) is now considered well known as a promising device for solid state lighting. It has the advantages of long durability, no mercury substance and good endurance of heavy impact. To satisfy the market demands of the thin-film liquid crystal display (LCD) and the green product, the LED is applied to as the light source to make display thinner, lighter, no Hg containing. In this research, the LED uniform lightguide is demonstrated because it enables the point-like light to distribute propagating-light line pattern successfully. By optimizing the size and the radian of the device, the designed LED uniform lightguide can achieve the output efficiency more than 85%, and its illuminative uniformity is improved about 85%. Thus, the LED uniform lightguide not only can decrease the number of LED to save the space, but also enhance the optical efficiency. In the future, a novel LED uniform module could make displays thinner and lighter for backlight system applications.

  2. An Adaptive Algorithm of Local dimming for Liquid Crystal Displays

    Directory of Open Access Journals (Sweden)

    Huaxia Wu


    Full Text Available The local dimming backlight technique enables liquid crystal display to present images with high contrast ratio and low power consumption. Considering that it is more important to make sure a high quality of the displayed image when reducing the power consumption, therefore, in this paper the new algorithm chooses RPSNR (the peak signal-to-noise ratio =30 as the lowest standard to guarantee the quality of image. RPSNR =30 could provide a value that the maximum distortion of the image can be accepted, then, we substitute the maximum gray level of each region into the formula to judge whether satisfy the flow chart. If the value do not meet the condition, we decrease it one by one until find the right value. Finally, we take the luminance of the right value as backlight luminance.   Meanwhile, a method is also proposed in this paper to simplify the calculation time. Successive searches will be made on the basis of the n (ranging from 0.1 to 1 times of the maximum luminance, and stop when RPSNR>=30. However, in order to guarantee the quality of the image, the 0.7 times of the maximum luminance is used as the minimum backlight luminance. In the end, we only choose 0.7, 0.8 and 0.9 times of the maximum luminance as backlight luminance.

  3. Study on Birefringent Color Generation for a Reflective Ferroelectric Liquid Crystal Display (United States)

    Valyukh, Sergiy; Valyukh, Iryna; Xu, Peizhi; Chigrinov, Vladimir


    We study the possibility of a layer of a surface stabilized ferroelectric liquid crystal coupled with several retardation plates for birefringent color generation. Double and single polarizer reflective bistable dichromatic ferroelectric liquid crystal displays are considered. We demonstrate that one or two retardation plates are sufficient for a display having good color characteristics and high brightness. Optimal parameters for green/red and blue/yellow ferroelectric liquid crystal displays are found.

  4. Micropatterning with a liquid crystal display (LCD) projector. (United States)

    Itoga, Kazuyoshi; Kobayashi, Jun; Yamato, Masayuki; Okano, Teruo


    Photolithography has been applied to biological applications such as cell and protein micropatterning and the fabrication of microfluidic channels. However, the preparation of photomasks for projecting micropattern lighting images is often time consuming and costly. Therefore, we have developed maskless photolithography devices by modifying the optics of commercially available liquid crystal display (LCD) projectors from extended to reduced projection. The developed second and third devices produce practically a centimeter-scale micropattern by dividing an original large mask pattern into several patterns, which are individually and synchronously exposed to substrates with a motorized XY-stage, applying them to cell micropatterning and polydimethylsiloxane (PDMS) microfluidic device production. The first part of this chapter describes the developments of the maskless photolithography devices. The second part describes the exposure control system with a motorized XY-stage. The third part describes the applications of devices to cell micropatterning. The last part describes the application of the devices to the fabrication of the PDMS microfluidic channel. Maskless photolithography with an LCD projector has a large advantage with no requirement for a photomask. In particular, the maskless photolithography devices show a greater power by optimizing the conditions of pattern size and shape.

  5. SHALE: An Efficient Algorithm for Allocation of Guaranteed Display Advertising

    CERN Document Server

    Bharadwaj, Vijay; Ma, Wenjing; Nagarajan, Chandrashekhar; Tomlin, John; Vassilvitskii, Sergei; Vee, Erik; Yang, Jian


    Motivated by the problem of optimizing allocation in guaranteed display advertising, we develop an efficient, lightweight method of generating a compact {\\em allocation plan} that can be used to guide ad server decisions. The plan itself uses just O(1) state per guaranteed contract, is robust to noise, and allows us to serve (provably) nearly optimally. The optimization method we develop is scalable, with a small in-memory footprint, and working in linear time per iteration. It is also "stop-anytime", meaning that time-critical applications can stop early and still get a good serving solution. Thus, it is particularly useful for optimizing the large problems arising in the context of display advertising. We demonstrate the effectiveness of our algorithm using actual Yahoo! data.

  6. Investigation of Energy-Efficient Supermarket Display Cases

    Energy Technology Data Exchange (ETDEWEB)

    Walker, D.H.


    contributing about 3/4 of that fraction. Consequently, the focus of this investigation has tilted toward the open, vertical, multi-deck medium temperature case type. Various technologies and control methods are energy efficiency measures (EEMs) that could be applied to display cases and result in the reduction of the refrigeration load and of the energy consumption of the supermarket refrigeration system. An extensive evaluation of the EEMs was conducted in order to select those that met the following criteria: (1) Near-term implementation--All EEMs considered could be implemented with existing refrigeration hardware and technology. (2) Potential for energy-efficiency improvements--Energy savings and/or refrigeration load reduction must be obtained by the implementation of the EEM. (3) Enhancement of the ability to maintain target product temperature--Proper operation of the display case and maintenance of the stored product temperature could not be compromised by the use of the EEM. The energy impact of a number of viable display case EEMs was quantified by performing whole building hourly simulations. A special version of the U.S. Department of Energy's (DOE-2.3) program was used to develop a model of a supermarket. The model was then calibrated using available end-use monitored data to increase confidence in simulation results.

  7. Characterization of the anamorphic and frequency dependent phenomenon in Liquid Crystal on Silicon displays (United States)

    Lobato, L.; Lizana, A.; Márquez, A.; Moreno, I.; Iemmi, C.; Campos, J.; Yzuel, M. J.


    The diffractive efficiency of Liquid Crystal on Silicon (LCoS) displays can be greatly diminished by the appearance of temporal phase fluctuations in the reflected beam, depolarization effects and also because of phase modulation depths smaller than 2π. In order to maximize the efficiency of the Diffractive Optical Elements (DOEs) implemented in the LCoS device, the Minimum Euclidean Distance principle can be applied. However, not all the diffractive elements can be corrected in the same way due to the anamorphic and frequency dependent phenomenon, which is related to the LCoS response, largely dependending on the period and the spatial orientation of the generated DOE. Experimental evidence for the anamorphic and frequency dependent phenomenon is provided in this paper, as well as a comparative study between the efficiency obtained for binary gratings of different periods

  8. Low voltage transflective blue-phase liquid crystal display with a non-uniform etching substrate (United States)

    Wang, Jian; Mao, Jiang-Lin; Fan, Hao-Xiang; Wang, Qiong-Hua


    A transflective polymer-stabilized blue-phase liquid crystal display (BP-LCD) with a non-uniform etching substrate is proposed. In-plane switching (IPS) electrodes on the bottom substrate are put on the different gaps, and the bottom substrate between the electrodes is etched into different depths in transmissive (T) and reflective (R) regions. This structure can balance the optical phase retardation in the two regions and is helpful to achieve well-matched voltag-dependent transmittance and reflectance curves. This transflective display has high optical efficiency, a wide viewing angle, and low operating voltage (approximately 6 V). Project supported by the National Natural Science Foundation of China (Grant Nos. 61535007 and 61320106015) and the National Basic Research Program of China (Grant No. 2013CB328802).

  9. An electrochemical study of a liquid crystal used in information displays (United States)

    Oglesby, D. M.; Kern, J. B.; Robertson, J. B.


    The operational lifetime of liquid crystal displays were investigated. Electrochemical reaction at the electrodes of the display can cause failure after 2000 to 3000 hours of operation. Studies using cyclic voltametry of electrochemical reactions of N (p-methoxybenzilidene p-butylaniline (MBBA), a nematic liquid crystal were made. These studies indicate the presence of a reversible reduction of MBBA at the cathode, and that the reduction product undergoes a further reaction leading to products which are not reversibly oxidized. It is concluded that the degradation of the liquid crystal in displays can be reduced with a suitable frequency of alternating voltage.

  10. A structurally informed autotransporter platform for efficient heterologous protein secretion and display

    Directory of Open Access Journals (Sweden)

    Jong Wouter SP


    Full Text Available Abstract Background The self-sufficient autotransporter (AT pathway, ubiquitous in Gram-negative bacteria, combines a relatively simple protein secretion mechanism with a high transport capacity. ATs consist of a secreted passenger domain and a β-domain that facilitates transfer of the passenger across the cell-envelope. They have a great potential for the extracellular expression of recombinant proteins but their exploitation has suffered from the limited structural knowledge of carrier ATs. Capitalizing on its crystal structure, we have engineered the Escherichia coli AT Hemoglobin protease (Hbp into a platform for the secretion and surface display of heterologous proteins, using the Mycobacterium tuberculosis vaccine target ESAT6 as a model protein. Results Based on the Hbp crystal structure, five passenger side domains were selected and one by one replaced by ESAT6, whereas a β-helical core structure (β-stem was left intact. The resulting Hbp-ESAT6 chimeras were efficiently and stably secreted into the culture medium of E. coli. On the other hand, Hbp-ESAT6 fusions containing a truncated β-stem appeared unstable after translocation, demonstrating the importance of an intact β-stem. By interrupting the cleavage site between passenger and β-domain, Hbp-ESAT6 display variants were constructed that remain cell associated and facilitate efficient surface exposure of ESAT6 as judged by proteinase K accessibility and whole cell immuno-EM analysis. Upon replacement of the passenger side domain of an alternative AT, EspC, ESAT6 was also efficiently secreted, showing the approach is more generally applicable to ATs. Furthermore, Hbp-ESAT6 was efficiently displayed in an attenuated Salmonella typhimurium strain upon chromosomal integration of a single encoding gene copy, demonstrating the potential of the Hbp platform for live vaccine development. Conclusions We developed the first structurally informed AT platform for efficient secretion and

  11. Controllable liquid crystal gratings for an adaptive 2D/3D auto-stereoscopic display (United States)

    Zhang, Y. A.; Jin, T.; He, L. C.; Chu, Z. H.; Guo, T. L.; Zhou, X. T.; Lin, Z. X.


    2D/3D switchable, viewpoint controllable and 2D/3D localizable auto-stereoscopic displays based on controllable liquid crystal gratings are proposed in this work. Using the dual-layer staggered structure on the top substrate and bottom substrate as driven electrodes within a liquid crystal cell, the ratio between transmitting region and shielding region can be selectively controlled by the corresponding driving circuit, which indicates that 2D/3D switch and 3D video sources with different disparity images can reveal in the same auto-stereoscopic display system. Furthermore, the controlled region in the liquid crystal gratings presents 3D model while other regions maintain 2D model in the same auto-stereoscopic display by the corresponding driving circuit. This work demonstrates that the controllable liquid crystal gratings have potential applications in the field of auto-stereoscopic display.

  12. 77 FR 3793 - Certain Liquid Crystal Display Devices, Including Monitors, Televisions, and Modules, and... (United States)


    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Certain Liquid Crystal Display Devices, Including Monitors, Televisions, and Modules, and Components Thereof; Request for Statements on the Public Interest AGENCY: U.S. International Trade Commission...

  13. 77 FR 5055 - Certain Liquid Crystal Display Devices and Products Containing the Same; Determination Not To... (United States)


    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Certain Liquid Crystal Display Devices and Products Containing the Same; Determination Not To Review Initial Determination Granting Joint Motion To Terminate Based on Settlement Agreement...

  14. 77 FR 45375 - Certain Liquid Crystal Display Devices, Including Monitors, Televisions, Modules, and Components... (United States)


    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Certain Liquid Crystal Display Devices, Including Monitors, Televisions, Modules, and Components Thereof; Commission Determination Not To Review an Initial Determination Terminating the Investigation as...

  15. Horizontally-aligned carbon nanotubes arrays and their interactions with liquid crystal molecules: Physical characteristics and display applications

    Directory of Open Access Journals (Sweden)

    Frédérick Roussel


    Full Text Available We report on the physical characteristics of horizonthally-grown Single-Walled Carbon Nanotubes (h-al-SWNT arrays and their potential use as transparent and conducting alignment layer for liquid crystals display devices. Microscopy (SEM and AFM, spectroscopic (Raman and electrical investigations demonstrate the strong anisotropy of h-al-SWNT arrays. Optical measurements show that h-al-SWNTs are efficient alignment layers for Liquid Crystal (LC molecules allowing the fabrication of optical wave plates. Interactions between h-al-SWNT arrays and LC molecules are also investigated evidencing the weak azimuthal anchoring energy at the interface, which, in turn, leads to LC devices with a high pretilt angle. The electro-optical reponses of h-al-SWNT/LC cells demonstrate that h-al-SWNT arrays are efficient nanostructured electrodes with potential use for the combined replacement of Indium Tin Oxyde and polymeric alignment layers in conventional displays.

  16. Modeling the Color Image and Video Quality on Liquid Crystal Displays with Backlight Dimming

    DEFF Research Database (Denmark)

    Korhonen, Jari; Mantel, Claire; Burini, Nino


    Objective image and video quality metrics focus mostly on the digital representation of the signal. However, the display characteristics are also essential for the overall Quality of Experience (QoE). In this paper, we use a model of a backlight dimming system for Liquid Crystal Display (LCD...

  17. Single-substrate liquid-crystal displays by photo-enforced stratification (United States)

    Penterman, Roel; Klink, Stephen I.; de Koning, Henk; Nisato, Giovanni; Broer, Dirk J.


    Data visualization plays a crucial role in our society, as illustrated by the many displays that surround us. In the future, displays may become even more pervasive, ranging from individually addressable image-rendering wall hangings to data displays integrated in clothes. Liquid-crystal displays (LCDs) provide most of the flat-panel displays currently used. To keep pace with the ever-increasing possibilities afforded by developments in information technology, we need to develop manufacturing processes that will make LCDs cheaper and larger, with more freedom in design. Existing batch processes for making and filling LCD cells are relatively expensive, with size and shape limitations. Here we report a cost-effective, single-substrate technique in which a coated film is transformed into a polymer-covered liquid-crystal layer. This approach is based on photo-enforced stratification: a two-step photopolymerization-induced phase separation of a liquid-crystal blend and a polymer precursor. The process leads to the formation of micrometre-sized containers filled with a switchable liquid-crystal phase. In this way, displays can be produced on a variety of substrates using current coating technology. The developed process may be an important step towards new technologies such as `display-on-anything' and `paintable displays'.

  18. Interactive auto-stereoscopic display with efficient and flexible interleaving (United States)

    Jung, Kyungboo; Park, Jong-Il; Choi, Byung-Uk


    We propose a system that displays a three-dimensional (3D) scene on a 3D display device, consisting of a flat-panel display and a slanted parallax barrier, which can directly manipulate virtual 3D objects in real time. The proposed system consists of a 3D scene display part and a user interaction part. First, we propose a multi-view image interleaving method that considers the distance between a user and a display device for a slanted parallax barrier-based 3D display. Second, we define hand motion parameters for convenient hand motion analysis, and we propose a hand gesture recognition method that uses dynamic time warping (DTW) with specified hand motion parameters for user interaction. Thus, the proposed system makes it possible to see in any position, and viewers can perform event actions without regard to the shape or timing of hand motions.

  19. Polymer-stabilized ferroelectric liquid crystal for flexible displays using plastic substrates (United States)

    Fujikake, Hideo; Murashige, Takeshi; Sato, Hiroto; Iino, Yoshiki; Kikuchi, Hiroshi; Kawakita, Masahiro; Tsuchiya, Yuzuru


    We have developed a ferroelectric liquid crystal device with a novel structure containing a polymer fiber network for flexible lightweight displays using thin plastic substrates. The aligned polymer fibers of sub-micrometers -diameter were formed under ultraviolet light irradiation in a heated nematic- phase solution consisting of liquid crystal and monofunctional acrylate monomer. The rigid polymer network was found to adhere to the two plastic substrates, and the uniform liquid crystal alignment provided a contrast ratio of 100:1 for a monomer concentration of 20 wt%. This device achieves a continuous grayscale capability as a result of change in the spatial distribution of small liquid crystal domains, and also exhibits a fast response time of 80 microsecond(s) due to high-purity separation of polymer and liquid crystal materials. It therefore has attractive features for flexible moving-image display applications.

  20. Charge retention of twisted nematic liquid-crystal displays (United States)

    Yang, K. H.


    A simulated thin-film transistor (TFT) circuit has been built to drive the twisted nematic (TN) cell for the measurements of charge retention and the transmission versus peak voltage applied to the drain electrode of the simulated TFT using the gate pulse width as a parameter. The established rule that the transmission of the TN cell depends only on the rms voltage applied to the cell has been confirmed by calculating the rms voltage of the charge retention curves in correlation with the measured transmissions. The deviation of the decaying charge retention curves from the exponential behavior has been observed and can be qualitatively explained by a combination of the dielectric and transport properties of nematic liquid-crystal medium.

  1. Liquid crystal cell design of VGA field sequential color LCoS display (United States)

    Liu, Yanyan; Geng, Weidong; Dai, Yongping


    The design of liquid crystal cell is an important factor to determine the display quality of LCoS display device. The goal of this paper is to gain VGA field sequential color (FSC) LCoS device used for near-to-eye system. The characteristics of optics and electrooptics for the twist nematic liquid crystal material and the material requirements of the FSC LCoS were studied. The LCOS liquid crystal cell optimized by dynamic parameter space method had an uniform reflectivity (about 90%) for the light with wave length from 450nm to 650nm. Both considering the electrooptic response curve of liquid crystal and the relationship between the contrast ratio and pixel size, we determined to use high speed twist nematic liquid crystal working in normally white mode. The liquid crystal cell gap and the pixel size were determined as 2.5um and 12um, respectively. The VGA FSC LCoS device was fabricated with SMIC 0.35um CMOS process and filled with LC-A liquid crystal of Merck in Varitronix. The measurement showed that the response time of liquid crystal from light to dark was 1.8ms and from dark to light was 4.4ms. The contrast ratio is bigger than 50:1. The LCoS displays well.

  2. Time-multiplexed three-dimensional displays based on directional backlights with fast-switching liquid-crystal displays. (United States)

    Chien, Ko-Wei; Shieh, Han-Ping D


    An autostereoscopic display using a directional backlight with a fast-switching liquid-crystal (LC) display was designed and fabricated to obtain a better perception of 3D images by enhanced resolution and brightness. A grooved light guide in combination with an asymmetric focusing foil was utilized to redirect the emitting cones of light to the left and right eyes, respectively. By designing the groove structures of the focusing foil with rotation from -1.5 degrees to 1.5 degrees in the gradient and having the pitch ratio of the grooved light guide to the focusing foil of less than 3, the boundary angle then shifts from normal viewing and the moiré phenomenon can be suppressed. Cross talk of less than 6% and a LC response time of faster than 7.1 ms further improve the stereoscopic image perception. Additionally, 2D-3D compatibility is provided.


    Institute of Scientific and Technical Information of China (English)



    A new technique to uniformly align liquid crystal molecules is presented.The technique is based on producing an anisotropic surface on the glass substrate coated with photo-polymers by photo-polymerization of linear polarized UVlight.The orientation of liquid crystal molecules is governed by the direction of the polarized vector of UV-light.Using this method,we have studied the photo-polymer PSi-CM aligning LC 6710A molecules.The liquid crystal microscopic texture between crossed polarizers,optical retardation from liquid crystal layers and electro-optical properties of twisted nematic liquid crystal display cell are obtained,which was prepared with one side -photo-alignment and the other siderebbed substrate.

  4. Reduction of image blurring in an autostereoscopic multilayer liquid crystal display (United States)

    Gotoda, Hironobu


    A multilayer liquid crystal display (LCD) is a display device constructed by stacking multiple liquid crystal layers on top of a light source. As shown in a previous study, a multilayer LCD can deliver varying images depending on the viewers'eye positions, and can be used for auto-stereoscopic 3D viewing. However, undesirable blurring is sometimes observed in the images that a viewer receives from the display. Such blurring is notable especially around objects in the scene that are far away from the viewer. To address this problem, we propose to put a convex lens in front of the layers of liquid crystal. The lens refracts the beams of light, thus bringing the effects of moving the objects to nearer positions. Through a simulation-based study, we show that an optimal choice exists for the focal length of the lens, which reduces the local image blurring while not compromising the overall image quality.

  5. Phase separation of monomer in liquid crystal mixtures and surface morphology in polymer-stabilized vertical alignment liquid crystal displays

    Energy Technology Data Exchange (ETDEWEB)

    Lyu, Jae Jin; Lee, Jun Hyup; Kim, Kyeong Hyeon [Development Center, LCD Business, SAMSUNG Electronics Co. LTD., Tangjeong-Myeon, Asan, Chungnam 336-741 (Korea, Republic of); Kikuchi, Hirotsuku; Higuchi, Hiroki [Institute for Materials Chemistry and Engineering, Kyushu University, 6-1 Kasuga-Koen, Kasuga 816-8580 (Japan); Kim, Dae Hyun; Lee, Seung Hee, E-mail:, E-mail: [Department of BIN Fusion Technology and Department of Polymer-Nano Science and Technology, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of)


    The polymer-stabilized vertically aligned (PS-VA) liquid crystal display (LCD) driving mode has high potential for manufacturing low power consuming displays due to the higher transmittance and fast response as compared with the existing patterned vertically aligned and multi-domain vertically aligned modes. In this paper we have investigated the reaction mechanisms of monomer-liquid crystal blends to form a surface pre-tilt angle of liquid crystal in vertical alignment LCD associated with a fishbone electrode structure. The observed sizes of polymer bumps formed on the substrates were found to be dependent on the exposed UV wavelength and were almost equal in both top and bottom substrates. When a large UV wavelength was used, the phase separation mechanism of monomer in PS-VA mode was found nearly isotropic rather than anisotropic in contrast to the previous studies.

  6. Flexoelectric effect in an in-plane switching (IPS) liquid crystal cell for low-power consumption display devices (United States)

    Kim, Min Su; Bos, Philip J.; Kim, Dong-Woo; Yang, Deng-Ke; Lee, Joong Hee; Lee, Seung Hee


    Technology of displaying static images in portable displays, advertising panels and price tags pursues significant reduction in power consumption and in product cost. Driving at a low-frequency electric field in fringe-field switching (FFS) mode can be one of the efficient ways to save powers of the recent portable devices, but a serious drop of image-quality, so-called image-flickering, has been found in terms of the coupling of elastic deformation to not only quadratic dielectric effect but linear flexoelectric effect. Despite of the urgent requirement of solving the issue, understanding of such a phenomenon is yet vague. Here, we thoroughly analyze and firstly report the flexoelectric effect in in-plane switching (IPS) liquid crystal cell. The effect takes place on the area above electrodes due to splay and bend deformations of nematic liquid crystal along oblique electric fields, so that the obvious spatial shift of the optical transmittance is experimentally observed and is clearly demonstrated based on the relation between direction of flexoelectric polarization and electric field polarity. In addition, we report that the IPS mode has inherent characteristics to solve the image-flickering issue in the low-power consumption display in terms of the physical property of liquid crystal material and the electrode structure.

  7. Fast-response liquid-crystal lens for 3D displays (United States)

    Liu, Yifan; Ren, Hongwen; Xu, Su; Li, Yan; Wu, Shin-Tson


    Three-dimensional (3D) display has become an increasingly important technology trend for information display applications. Dozens of different 3D display solutions have been proposed. The autostereoscopic 3D display based on lenticular microlens array is a promising approach, and fast-switching microlens array enables this system to display both 3D and conventional 2D images. Here we report two different fast-response microlens array designs. The first one is a blue phase liquid crystal lens driven by the Pedot: PSS resistive film electrodes. This BPLC lens exhibits several attractive features, such as polarization insensitivity, fast response time, simple driving scheme, and relatively low driving voltage, as compared to other BPLC lens designs. The second lens design has a double-layered structure. The first layer is a polarization dependent polymer microlens array, and the second layer is a thin twisted-nematic (TN) liquid crystal cell. When the TN cell is switched on/off, the traversing light through the polymeric lens array is either focused or defocused, so that 2D/3D images are displayed correspondingly. This lens design has low driving voltage, fast response time, and simple driving scheme. Simulation and experiment demonstrate that the performance of both switchable lenses meet the requirement of 3D display system design.

  8. Bistable light shutter using dye-doped liquid crystals for a see-through display (United States)

    Huh, Jae-Won; Heo, Joon; Yu, Byeong-Huh; Yoon, Tae-Hoon


    See-through displays have got high attention as one of the next generation display devices. Especially, see-through displays that use organic light-emitting diodes (OLEDs) and liquid crystal displays (LCDs) have been actively studied. However, a see-through display using OLEDs cannot provide black color because of their see-through area. Although a see-through display using LCDs can provide black color with crossed polarizers, it cannot block the background. This inevitable problem can be solved by placing a light shutter at the back of a see-through display. To maintain the transparent or opaque state, an electric field must be applied to a light shutter. To achieve low power consumption, a bistable light shutter using polymer-stabilized cholesteric liquid crystals (CLC) has been proposed. It is switchable between the translucent and transparent states only. Therefore, it cannot provide black color. Moreover, it cannot block the background perfectly because of poor performance in the translucent state. In this work we will introduce a bistable light shutter using dye-doped CLCs. To improve the electro-optic characteristics in the opaque state, we employed a crossed electrode structure instead of a parallel one. We will demonstrate that the light shutter can exhibit stable bistable operation between the transparent homeotropic and opaque focal-conic states thanks to polymer stabilization.

  9. Fourier series analysis of fractal lenses: theory and experiments with a liquid-crystal display. (United States)

    Davis, Jeffrey A; Sigarlaki, Sean P; Craven, Julia M; Calvo, María Luisa


    We report on a Fourier series approach that predicts the focal points and intensities produced by fractal zone plate lenses. This approach allows us to separate the effects of the fractal order from those of the lens aperture. We implement these fractal lenses onto a liquid-crystal display and show experimental verification of our theory.

  10. Searching for the preferred backlight intensity in liquid crystal displays with local backlight dimming

    DEFF Research Database (Denmark)

    Korhonen, Jari; Mantel, Claire; Burini, Nino


    Local backlight dimming is one of the most promising techniques for reducing power consumption and improving contrast characteristics of liquid crystal displays (LCD). In practice, due to light diffusion and a smaller number of backlight sources than pixels, local backlight dimming must often trade...

  11. The development of self-assembled liquid crystal display alignment layers

    NARCIS (Netherlands)

    Hoogboom, J.; Elemans, J.A.A.W.; Rowan, A.E.; Rasing, T.H.M.; Nolte, R.J.M.


    From simple pocket calculators to mobile telephones and liquid crystal display (LCD)-TV, over the past few decades, devices based on LCD technology have proliferated and can now be found in all conceivable aspects of everyday life. Although used in cutting-edge technology, it is surprising that a vi

  12. 77 FR 37067 - Certain Liquid Crystal Display Devices, Including Monitors, Televisions, Modules, and Components... (United States)


    ... [Federal Register Volume 77, Number 119 (Wednesday, June 20, 2012)] [Notices] [Pages 37067-37068] [FR Doc No: 2012-15005] INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-741/749] Certain Liquid Crystal Display Devices, Including Monitors, Televisions, Modules, and Components Thereof; Final...

  13. Technical and radiological image quality comparison of different liquid crystal displays for radiology

    Directory of Open Access Journals (Sweden)

    Dams FE


    Full Text Available Francina EM Dams,2 KY Esther Leung,1 Pieter HM van der Valk,2 Marc CJM Kock,2 Jeroen Bosman,1 Sjoerd P Niehof1 1Medical Physics and Technology, 2Department of Radiology, Albert Schweitzer Hospital, Dordrecht, The Netherlands Background: To inform cost-effective decisions in purchasing new medical liquid crystal displays, we compared the image quality in displays made by three manufacturers. Methods: We recruited 19 radiologists and residents to compare the image quality of four liquid crystal displays, including 3-megapixel Barco®, Eizo®, and NEC® displays and a 6-megapixel Barco display. The evaluators were blinded to the manufacturers' names. Technical assessments were based on acceptance criteria and test patterns proposed by the American Association of Physicists in Medicine. Radiological assessments were performed on images from the American Association of Physicists in Medicine Task Group 18. They included X-ray images of the thorax, knee, and breast, a computed tomographic image of the thorax, and a magnetic resonance image of the brain. Image quality was scored on an analog scale (range 0–10. Statistical analysis was performed with repeated-measures analysis of variance. Results: The Barco 3-megapixel display passed all acceptance criteria. The Eizo and NEC displays passed the acceptance criteria, except for the darkest pixel value in the grayscale display function. The Barco 6-megapixel display failed criteria for the maximum luminance response and the veiling glare. Mean radiological assessment scores were 7.8±1.1 (Barco 3-megapixel, 7.8±1.2 (Eizo, 8.1±1.0 (NEC, and 8.1±1.0 (Barco 6-megapixel. No significant differences were found between displays. Conclusion: According to the tested criteria, all the displays had comparable image quality; however, there was a three-fold difference in price between the most and least expensive displays. Keywords: data display, humans, radiographic image enhancement, user-computer interface

  14. Fundamental display properties of flexible devices containing polymer-stabilized ferroelectric liquid crystal between plastic substrates (United States)

    Fujikake, Hideo; Murashige, Takeshi; Sato, Hiroto; Iino, Yoshiki; Kawakita, Masahiro; Kikuchi, Hiroshi


    We describe several fundamental display properties of a flexible ferroelectric liquid crystal device containing polymer fibers between thin plastic substrates. The composite film of liquid crystal and polymer was created from a solution of liquid crystal and monomer materials between the plastic substrates under ultraviolet light irradiation. The dynamic electrooptic response to analog voltage pulses was examined with an incidence of laser beam light, and its light modulation property exhibited good linearity in continuous gray-scale capability. The excellent spatial uniformity of liquid crystal alignment formed between the flexible substrates resulted in high-contrast light modulation, although slight spontaneous bending of liquid crystal alignment in the device plane was recognized. When the laser light beam was obliquely incident on the flexible display device, the measured transmittance revealed that the device has a wide viewing angle of more than 100 deg without contrast reversal. This is considered to be caused by the molecular switching in the device plane and the thin electrooptic layer in the display device.

  15. A Polarizer-free Liquid Crystal Display Using Dye-doped Liquid Crystal Gels


    Lin, Yi-Hsin; Yang, Jhih-Ming; Lin, Hung-Chun; Wu, Jing-Nuo


    In conclusion, we have introduced and demonstrated polarizer-free LCDs using dye-doped LC gels. These polarizer-free dye-doped LC gels exhibit high reflectance, high contrast ratio, wide viewing angle, and fast response time. Especially the low temperature process is favorable for flexible displays. The gel-like materials assist stabilizing the flexible display under trimming. Our dye-doped LC gels provide a stable LC mode and open a new window in paper-like flexible displays. A polarizer-fre...

  16. Introduction to grayscale calibration and related aspects of medical imaging grade liquid crystal displays. (United States)

    Fetterly, Kenneth A; Blume, Hartwig R; Flynn, Michael J; Samei, Ehsan


    Consistent presentation of digital radiographic images at all locations within a medical center can help ensure a high level of patient care. Currently, liquid crystal displays (LCDs) are the electronic display technology of choice for viewing medical images. As the inherent luminance (and thereby perceived contrast) properties of different LCDs can vary substantially, calibration of the luminance response of these displays is required to ensure that observer perception of an image is consistent on all displays. The digital imaging and communication in medicine (DICOM) grayscale standard display function (GSDF) defines the luminance response of a display such that an observer's perception of image contrast is consistent throughout the pixel value range of a displayed image. The main purpose of this work is to review the theoretical and practical aspects of calibration of LCDs to the GSDF. Included herein is a review of LCD technology, principles of calibration, and other practical aspects related to calibration and observer perception of images presented on LCDs. Both grayscale and color displays are considered, and the influence of ambient light on calibration and perception is discussed.

  17. Assessment of Anisotropic Semiconductor Nanorod and Nanoplatelet Heterostructures with Polarized Emission for Liquid Crystal Display Technology

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, Patrick D.; Souza, João B.; Fedin, Igor; She, Chunxing; Lee, Byeongdu; Talapin, Dmitri V.


    Semiconductor nanorods can emit linear-polarized light at efficiencies over 80%. Polarization of light in these systems, confirmed through single-rod spectroscopy, can be explained on the basis of the anisotropy of the transition dipole moment and dielectric confinement effects. Here we report emission polarization in macroscopic semiconductor polymer composite films containing CdSe/CdS nanorods and colloidal CdSe nanoplatelets. Anisotropic nanocrystals dispersed in polymer films of poly butyl-co-isobutyl methacrylate (PBiBMA) can be stretched mechanically in order to obtain unidirectionally aligned arrays. A high degree of alignment, corresponding to an orientation factor of 0.87, was achieved and large areas demonstrated polarized emission, with the contrast ratio I-parallel to/I-perpendicular to= 5.6, making these films viable candidates for use in liquid crystal display (LCD) devices. To some surprise, we observed significant optical anisotropy and emission polarization for 2D CdSe nanoplatelets with the electronic structure of quantum wells. The aligned nanorod arrays serve as optical funnels, absorbing unpolarized light and re-emitting light from deep-green to red with quantum efficiencies over 90% and high degree of linear polarization. Our results conclusively demonstrate the benefits of anisotropic nanostructures for LCD backlighting. The polymer films with aligned CdSe/CdS dot-in-rod and rod-in-rod nanostructures show more than 2-fold enhancement of brightness compared to the emitter layers with randomly oriented nanostructures. This effect can be explained as the combination of linearly polarized luminescence and directional emission from individual nanostructures.

  18. Recycling acetic acid from polarizing film of waste liquid crystal display panels by sub/supercritical water treatments. (United States)

    Wang, Ruixue; Chen, Ya; Xu, Zhenming


    Waste liquid crystal display (LCD) panels mainly contain inorganic materials (glass substrate) and organic materials (polarizing film and liquid crystal). The organic materials should be removed first since containing polarizing film and liquid crystal is to the disadvantage of the indium recycling process. In the present study, an efficient and environmentally friendly process to obtain acetic acid from waste LCD panels by sub/supercritical water treatments is investigated. Furthermore, a well-founded reaction mechanism is proposed. Several highlights of this study are summarized as follows: (i) 99.77% of organic matters are removed, which means the present technology is quite efficient to recycle the organic matters; (ii) a yield of 78.23% acetic acid, a quite important fossil energy based chemical product is obtained, which can reduce the consumption of fossil energy for producing acetic acid; (iii) supercritical water acts as an ideal solvent, a requisite reactant as well as an efficient acid-base catalyst, and this is quite significant in accordance with the "Principles of Green Chemistry". In a word, the organic matters of waste LCD panels are recycled without environmental pollution. Meanwhile, this study provides new opportunities for alternating fossil-based chemical products for sustainable development, converting "waste" into "fossil-based chemicals".

  19. A technique to improve crystal channeling efficiency of charged particles

    CERN Document Server

    Tikhomirov, V V


    It is shown that a narrow plane cut near the crystal surface considerably increases the probability of capture into the stable channeling motion of positively charged particles entering a crystal at angles smaller than a quarter of the critical channeling angle with respect to the crystal planes. At smallest incidence angles the capture probability reaches 99 percent. A pair of crystals bent in orthogonal planes and provided with the cuts allows to reach a 99.9 percent efficiency of single-pass deflection of a proton beam with an ultra small divergence. Conditions necessary for efficient single-pass deflection of protons from the LHC beam halo are also discussed.

  20. Polymer-stabilized blue phase liquid crystal display with slanted wall-shaped electrodes

    Institute of Scientific and Technical Information of China (English)

    Feng Zhou; Qionghua Wang; Di Wu; Jianpeng Cui


    A polymer-stabilized blue phase liquid crystal display (BPLCD) with slanted wall-shaped electrodes is proposed. Compared with the traditional BPLCD with wall-shaped electrodes, the electrodes of the proposed BPLCD are slightly angled to obtain phase retardation in the entire cell even at the position of electrodes. The proposed BPLCD demonstrates a relatively higher average transmittance and overall brightness than the traditional BPLCD.%A polymer-stabilized blue phase liquid crystal display (BPLCD) with slanted wall-shaped electrodes is proposed.Compared with the traditional BPLCD with wall-shaped electrodes,the electrodes of the proposed BPLCD are slightly angled to obtain phase retardation in the entire cell even at the position of electrodes.The proposed BPLCD demonstrates a relatively higher average transmittance and overall brightness than the traditional BPLCD.Owing to the continuous improvement in image quality of liquid crystal displays (LCDs),they have been widely employed in desktop monitors,TVs,and mobile displays at present[1-5].With the development of LCDs the polymer-stabilized blue phase LCDs (BPLCDs)[6-11]can replace the conventional LCDs and become the nextgeneration display technology.The polymer-stabilized BPLCDs have numerous attractive features,such as submillisecond gray-to-gray response time,alignmentlayer-free process optically isotropic dark state and cell gap insensitivity[12-14].Because of these advantages,the fabrication processes of the BPLCDs are simplified,motion-image blurs are reduced,and color-sequential displays using RGB LEDs are enabled.

  1. Implementation and analysis of an autostereoscopic display using multiple liquid crystal layers (United States)

    Gotoda, Hironobu


    Multilayer displays are constructed by stacking multiple liquid crystal panels along with a pair of polarizers and a light source. Previous theoretical analyses have shown that such a display could exhibit the light field of a 3D scene if the panels in the display are properly controlled. In this study, we present an implementation of a monochromatic multilayer display using IPS-LCD panels, and report that a reasonable approximation of the light field is actually observed from the display. A major obstacle to constructing a multilayer display is the complexity of optical properties of LCD panels. Since an accurate analytic representation of panels' behavior is difficult to obtain, we have developed an approximate model specific to IPS-LCD cells, using which our implementation is built. We then evaluate the quality of the light field observed from the prototype implementation by examining the images photographed at several camera positions. The results show geometrically correct views are observable from the display within the viewing angle of 30 degrees.


    Institute of Scientific and Technical Information of China (English)

    LI Baozhong; HE Tianbai; DING Mengxian


    The disadvantages of Normally White Twisted Nematic Liquid Crystal Display (NW-TN-LCD) were discussed. The reason that the negative birefringent polyimide thin films were used to compensate NW-TN-LCD to decrease off-axis leakage, improve contrast ratios and enlarge viewing angles' was explained in this paper. A certain polyimide thin film was taken as an example to show compensation effect on NW-TN-LCD.

  3. Milestone in the History of Field-Effect Liquid Crystal Displays and Materials (United States)

    Schadt, Martin


    The history of digital electronics would have been very different without the invention of field-effect liquid crystal displays (LCDs) in 1970 and their sophisticated development and implementation into numerous products. Transmissive and reflective LCDs have become a key interface between man and machine. After almost 40 years of interdisciplinary R+D and engineering, today's LCDs enable virtually all display applications, including high definition television. Field-effect LCDs are characterized by flat design, low weight, low driving voltage, design flexibility, compatibility with silicon-on-glass and very low power consumption, especially in reflection. Their polarization-sensitive layer concept is the basis for sandwiching and integration of optical and electronic thin-film functions. The liquid crystal technology has become a fast growing industry over the past 38 years, today surpassing 100 billion, with many spin-offs into new areas. Prerequisite for field-effect LCDs and their large diversification potential is the unique self-organization of liquid crystals. New applications beyond displays based on self-organisation, smart boundary alignment, dedicated liquid crystalline materials and the ability of LCs to respond to electromagnetic fields, including light, are being developed. Examples for new applications are LC polymer thin-film optics, or synergies between LCDs and solid state back-lighting, such as inorganic and organic light emitting diodes (LEDs/OLEDs).

  4. Precise prediction of optical responses of liquid-crystal display products using a behavioral model of liquid crystal (United States)

    Park, Chansoo; Cho, Youngmin; Kim, Jong-Man; Kim, Jongbin; Lee, Seung-Woo


    We propose a precise circuit model to estimate transient optical responses of an active-matrix liquid crystal display (AMLCD). Liquid crystal (LC) molecules in the pixel is behaviorally modeled by using the first-order system that is described by Verilog-A. Capacitance-voltage (C-V) characteristics of a pixel determine the accuracy of the dynamic responses. Measuring C-V characteristics is impossible because pixels are driven by switching transistors in the AMLCD. We propose a method to obtain the C-V data from natural optical responses. Estimated optical responses based on the C-V data extracted by our proposal show more accurate results than those based on C-V data obtained by using transmittance-voltage data. It is demonstrated that our behavioral model enables us to predict very accurate transient responses, which makes it possible to design LCD products with lower costs.

  5. Application of pyrolysis process to remove and recover liquid crystal and films from waste liquid crystal display glass. (United States)

    Lu, Rixin; Ma, En; Xu, Zhenming


    Liquid crystal display (LCD) glass mainly consists of polarizing film, liquid crystal and glass substrate. Removing and recovering the liquid crystal and films from the LCD glass effectively has important significance for recovering the other parts. This study proposed a pyrolysis process to recover the organic parts from LCD glass. Through thermal gravimetric analysis, the pyrolysis temperature of the LCD glass could be chosen at 850 K. The removal rate of organic parts from LCD glass reached 87.87 wt%. Pyrolysis products consisted of 66.82 wt% oils, 21.01 wt% gaseous and 12.13 wt% residues. In addition, the oils contained 46.27 wt% acetic acid and 32.94 wt% triphenyl phosphate. Then, the pyrolysis mechanisms and products sources of the liquid crystal glass have been analyzed based on the information of bonds energy. The pyrolysis mechanism analysis proved that the products mainly consisted of acetic acid, triphenyl phosphate and C, which is consistent to the results of GC-MS analysis. A reasonable way has been put forward to recycle the pyrolysis products: acetic acid and triphenyl phosphate can be collected by distillation, the rest oils and gases can be used as fuel and the remained glass can be used to extract indium and to produce building materials.

  6. Benzothiazolium Single Crystals: A New Class of Nonlinear Optical Crystals with Efficient THz Wave Generation. (United States)

    Lee, Seung-Heon; Lu, Jian; Lee, Seung-Jun; Han, Jae-Hyun; Jeong, Chan-Uk; Lee, Seung-Chul; Li, Xian; Jazbinšek, Mojca; Yoon, Woojin; Yun, Hoseop; Kang, Bong Joo; Rotermund, Fabian; Nelson, Keith A; Kwon, O-Pil


    Highly efficient nonlinear optical organic crystals are very attractive for various photonic applications including terahertz (THz) wave generation. Up to now, only two classes of ionic crystals based on either pyridinium or quinolinium with extremely large macroscopic optical nonlinearity have been developed. This study reports on a new class of organic nonlinear optical crystals introducing electron-accepting benzothiazolium, which exhibit higher electron-withdrawing strength than pyridinium and quinolinium in benchmark crystals. The benzothiazolium crystals consisting of new acentric core HMB (2-(4-hydroxy-3-methoxystyryl)-3-methylbenzo[d]thiazol-3-ium) exhibit extremely large macroscopic optical nonlinearity with optimal molecular ordering for maximizing the diagonal second-order nonlinearity. HMB-based single crystals prepared by simple cleaving method satisfy all required crystal characteristics for intense THz wave generation such as large crystal size with parallel surfaces, moderate thickness and high optical quality with large optical transparency range (580-1620 nm). Optical rectification of 35 fs pulses at the technologically very important wavelength of 800 nm in 0.26 mm thick HMB crystal leads to one order of magnitude higher THz wave generation efficiency with remarkably broader bandwidth compared to standard inorganic 0.5 mm thick ZnTe crystal. Therefore, newly developed HMB crystals introducing benzothiazolium with extremely large macroscopic optical nonlinearity are very promising materials for intense broadband THz wave generation and other nonlinear optical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Apparatus and method for remotely monitoring a utility meter by use of a liquid crystal display

    Energy Technology Data Exchange (ETDEWEB)

    Gombrich, P.P.; Case, S.K.; Konicek, L.R.


    An apparatus is described for optically sensing the angular position of a pointer member fixedly mounted on a rotatable shaft for rotational movement therewith as the shaft rotates about an axis of rotation, the apparatus comprising: (a) a follower member fixedly interconnected into the rotatable shaft for rotation about the axis of rotation with the pointer member, the follower member and the pointer having a circumferential path of travel. The follower member has first and second opposite sides facing in opposite axial directions, a first portion of the first side being generally reflective for reflecting light in a forward direction and a second portion being generally absorptive; (b) light emitting means positioned forward of the following member for emitting light in a backward direction towards the first side of the follower member; (c) light detecting means positioned forward of the follower member for detecting light reflected off of the follower member in a forward direction; and (d) liquid crystal display means positioned forward of the follower member, between the follower member and the light detecting means. The liquid crystal display means defines six distinct areas disposed about the circumferential path of the follower member and a background area encompassing the remaining area of the liquid crystal shutter means.

  8. Efficient, deep-blue TADF-emitters for OLED display applications (Conference Presentation) (United States)

    Volz, Daniel; Baumann, Thomas


    Currently, the mobile display market is strongly shifting towards AMOLED technology, in order to enable curved and flexible displays. This leads to a growing demand for highly efficient OLED emitters to reduce the power consumption and increase display resolution at the same time. While highly efficient green and red OLEDs already found their place in commercial OLED-displays, the lack of efficient blue emitters is still an issue. Consequently, the active area for blue is considerably larger than for green and red pixels, to make up for the lower efficiency. We intend to close this efficiency-gap with novel emitters based on thermally activated delayed fluorescence (TADF) technology. Compared to state-of-the-art fluorescent dopants, the efficiency of TADF-emitters is up to four times higher. At the same time, it is possible to design them in a way to maintain deep blue emission, i.e. CIE y technology does not contain any rare elements, which allows for the fabrication of sustainable OLED technology. In this work, we highlight one of our recently developed blue TADF materials. Basic material properties as well as first device results are discussed. In a bottom-emitting device, a CIEx/CIEy coordinate of (0.16/0.17) was achieved with efficiency values close to 20% EQE.

  9. Cylindrical liquid crystal lenses system for autostereoscopic 2D/3D display (United States)

    Chen, Chih-Wei; Huang, Yi-Pai; Chang, Yu-Cheng; Wang, Po-Hao; Chen, Po-Chuan; Tsai, Chao-Hsu


    The liquid crystal lenses system, which could be electrically controlled easily for autostereoscopic 2D/3D switchable display was proposed. The High-Resistance liquid crystal (HRLC) lens utilized less controlled electrodes and coated a high-resistance layer between the controlled-electrodes was proposed and was used in this paper. Compare with the traditional LC lens, the HR-LC Lens could provide smooth electric-potential distribution within the LC layer under driving status. Hence, the proposed HR-LC Lens had less circuit complexity, low driving voltage, and good optical performance also could be obtained. In addition, combining with the proposed driving method called dual-directional overdriving method, the above method could reduce the switching time by applying large voltage onto cell. Consequently, the total switching time could be further reduced to around 2second. It is believed that the LC lens system has high potential in the future.

  10. Effect of wavelength on the laser patterning of a cholesteric liquid crystal display electrode

    Energy Technology Data Exchange (ETDEWEB)

    Li, C.H., E-mail: [Laser Application Technology Center / Industrial Technology Research Institute South (ITRI South),8 Gongyan Rd., Liujia Dist., Tainan City 734, Taiwan, R.O.C. (China); Lin, H.K. [Laser Application Technology Center / Industrial Technology Research Institute South (ITRI South),8 Gongyan Rd., Liujia Dist., Tainan City 734, Taiwan, R.O.C. (China); Graduate Institute of Materials Engineering, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung 912, Taiwan, R.O.C. (China)


    A 1064 nm fiber laser and a 355 nm ultraviolet solid-state laser with galvanometer scanners and F-theta lenses are used to rapidly etch the silver electrode pattern of a cholesteric liquid crystal display. These results of the two laser processes are that the 1064 nm laser effectively reduces the damage to the liquid crystal layer and underlying indium tin oxide layer, and reduces the heat-affected zone of the ablated silver electrode. - Highlights: ► Laser patterning reduces the process time and costs lower than screen printing process. ► Etching of silver electrodes using 355-nm and 1064-nm lasers is compared. ► 1064-nm fiber laser can improve throughput, lower cost, and increase pattern quality.

  11. Power generating reflective-type liquid crystal displays using a reflective polariser and a polymer solar cell (United States)

    Ho Huh, Yoon; Park, Byoungchoo


    We herein report the results of a study of a power generating reflective-type liquid crystal display (LCD), composed of a 90° twisted nematic (TN) LC cell attached to the top of a light-absorbing polymer solar cell (PSC), i.e., a Solar-LCD. The PSC consisted of a polymer bulk-heterojunction photovoltaic (PV) layer of poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] and [6,6]-phenyl C71 butyric acid methyl ester (PCDTBT:PCBM70), and showed a high power conversion efficiency of about 5%. In order to improve the visibility of the Solar-LCD, between the TN-LC and the PV cells we inserted a reflective polariser of a giant birefringent optical (GBO) film. The reflectivity from the Solar-LCD was observed to be considerably increased by more than 13-15% under illumination by visible light. The Solar-LCD also exhibited a significantly improved contrast ratio of more than 17-19. We believe there is a clear case for using such Solar-LCDs in new power-generating reflective-type displays; taken as a whole these results also demonstrate the possibility of their application in a number of energy-harvesting opto-electrical display devices.

  12. In-Plane Switching Mode for Liquid Crystal Displays Using a DNA Alignment Layer. (United States)

    Cha, Yun Jeong; Gim, Min-Jun; Oh, Kyunghwan; Yoon, Dong Ki


    We successfully fabricated the in-plane switching mode (IPS) LC display (LCD) based on a double stranded DNA (dsDNA) alignment layer. As widely known, the DNA has the right-handed double helical structure that has naturally grown grooves with a very regular period, which can be used as an alignment layer to control the orientation of liquid crystal (LC) molecules. The LC molecules on this topographical layer of DNA material align obliquely at a specific angle with respect to the direction of DNA chains, providing an instant and convenient tool for the fabrication of the IPS display compared to the conventional ways such as rubbing and mechanical shearing methods. The electro-optical performance and response time of this device were also investigated. Our result will be of great use in further exploration of the electro-optical properties of the other biomaterials.

  13. Towards an optimal model for a bistable nematic liquid crystal display device

    KAUST Repository

    Cummings, L. J.


    Bistable liquid crystal displays offer the potential for considerable power savings compared with conventional (monostable) LCDs. The existence of two stable field-free states that are optically distinct means that contrast can be maintained in a display without an externally applied electric field. An applied field is required only to switch the device from one state to the other, as needed. In this paper we examine a theoretical model of a possible bistable device, originally proposed by Cummings and Richardson (Euro J Appl Math 17:435-463 2006), and explore means by which it may be optimized, in terms of optical contrast, manufacturing considerations, switching field strength, and switching times. The compromises inherent in these conflicting design criteria are discussed. © 2013 Springer Science+Business Media Dordrecht.

  14. Holographic three-dimensional display and hologram calculation based on liquid crystal on silicon device [invited]. (United States)

    Li, Junchang; Tu, Han-Yen; Yeh, Wei-Chieh; Gui, Jinbin; Cheng, Chau-Jern


    Based on scalar diffraction theory and the geometric structure of liquid crystal on silicon (LCoS), we study the impulse responses and image depth of focus in a holographic three-dimensional (3D) display system. Theoretical expressions of the impulse response and the depth of focus of reconstructed 3D images are obtained, and experimental verifications of the imaging properties are performed. The results indicated that the images formed by holographic display based on the LCoS device were periodic image fields surrounding optical axes. The widths of the image fields were directly proportional to the wavelength and diffraction distance, and inversely proportional to the pixel size of the LCoS device. Based on the features of holographic 3D imaging and focal depth, we enhance currently popular hologram calculation methods of 3D objects to improve the computing speed of hologram calculation.

  15. Liquid-crystal displays for medical imaging: a discussion of monochrome versus color (United States)

    Wright, Steven L.; Samei, Ehsan


    A common view is that color displays cannot match the performance of monochrome displays, normally used for diagnostic x-ray imaging. This view is based largely on historical experience with cathode-ray tube (CRT) displays, and does not apply in the same way to liquid-crystal displays (LCDs). Recent advances in color LCD technology have considerably narrowed performance differences with monochrome LCDs for medical applications. The most significant performance advantage of monochrome LCDs is higher luminance, a concern for use under bright ambient conditions. LCD luminance is limited primarily by backlight design, yet to be optimized for color LCDs for medical applications. Monochrome LCDs have inherently higher contrast than color LCDs, but this is not a major advantage under most conditions. There is no practical difference in luminance precision between color and monochrome LCDs, with a slight theoretical advantage for color. Color LCDs can provide visualization and productivity enhancement for medical applications, using digital drive from standard commercial graphics cards. The desktop computer market for color LCDs far exceeds the medical monitor market, with an economy of scale. The performance-to-price ratio for color LCDs is much higher than monochrome, and warrants re-evaluation for medical applications.

  16. Temporal properties of liquid crystal displays: implications for vision science experiments.

    Directory of Open Access Journals (Sweden)

    Tobias Elze

    Full Text Available Liquid crystal displays (LCD are currently replacing the previously dominant cathode ray tubes (CRT in most vision science applications. While the properties of the CRT technology are widely known among vision scientists, the photometric and temporal properties of LCDs are unfamiliar to many practitioners. We provide the essential theory, present measurements to assess the temporal properties of different LCD panel types, and identify the main determinants of the photometric output. Our measurements demonstrate that the specifications of the manufacturers are insufficient for proper display selection and control for most purposes. Furthermore, we show how several novel display technologies developed to improve fast transitions or the appearance of moving objects may be accompanied by side-effects in some areas of vision research. Finally, we unveil a number of surprising technical deficiencies. The use of LCDs may cause problems in several areas in vision science. Aside from the well-known issue of motion blur, the main problems are the lack of reliable and precise onsets and offsets of displayed stimuli, several undesirable and uncontrolled components of the photometric output, and input lags which make LCDs problematic for real-time applications. As a result, LCDs require extensive individual measurements prior to applications in vision science.

  17. Pixel-level tunable liquid crystal lenses for auto-stereoscopic display (United States)

    Li, Kun; Robertson, Brian; Pivnenko, Mike; Chu, Daping; Zhou, Jiong; Yao, Jun


    Mobile video and gaming are now widely used, and delivery of a glass-free 3D experience is of both research and development interest. The key drawbacks of a conventional 3D display based on a static lenticular lenslet array and parallax barriers are low resolution, limited viewing angle and reduced brightness, mainly because of the need of multiple-pixels for each object point. This study describes the concept and performance of pixel-level cylindrical liquid crystal (LC) lenses, which are designed to steer light to the left and right eye sequentially to form stereo parallax. The width of the LC lenses can be as small as 20-30 μm, so that the associated auto-stereoscopic display will have the same resolution as the 2D display panel in use. Such a thin sheet of tunable LC lens array can be applied directly on existing mobile displays, and can deliver 3D viewing experience while maintaining 2D viewing capability. Transparent electrodes were laser patterned to achieve the single pixel lens resolution, and a high birefringent LC material was used to realise a large diffraction angle for a wide field of view. Simulation was carried out to model the intensity profile at the viewing plane and optimise the lens array based on the measured LC phase profile. The measured viewing angle and intensity profile were compared with the simulation results.

  18. Temporal properties of liquid crystal displays: implications for vision science experiments. (United States)

    Elze, Tobias; Tanner, Thomas G


    Liquid crystal displays (LCD) are currently replacing the previously dominant cathode ray tubes (CRT) in most vision science applications. While the properties of the CRT technology are widely known among vision scientists, the photometric and temporal properties of LCDs are unfamiliar to many practitioners. We provide the essential theory, present measurements to assess the temporal properties of different LCD panel types, and identify the main determinants of the photometric output. Our measurements demonstrate that the specifications of the manufacturers are insufficient for proper display selection and control for most purposes. Furthermore, we show how several novel display technologies developed to improve fast transitions or the appearance of moving objects may be accompanied by side-effects in some areas of vision research. Finally, we unveil a number of surprising technical deficiencies. The use of LCDs may cause problems in several areas in vision science. Aside from the well-known issue of motion blur, the main problems are the lack of reliable and precise onsets and offsets of displayed stimuli, several undesirable and uncontrolled components of the photometric output, and input lags which make LCDs problematic for real-time applications. As a result, LCDs require extensive individual measurements prior to applications in vision science.

  19. An efficient method for isolating antibody fragments against small peptides by antibody phage display

    DEFF Research Database (Denmark)

    Duan, Zhi; Siegumfeldt, Henrik


    We generated monoclonal scFv (single chain variable fragment) antibodies from an antibody phage display library towards three small synthetic peptides derived from the sequence of s1-casein. Key difficulties for selection of scFv-phages against small peptides were addressed. Small peptides do....... The scFvs were sequenced and characterized, and specificity was characterized by ELISA. The methods developed in this study are universally applicable for antibody phage display to efficiently produce antibody fragments against small peptides....

  20. Biological treatment of thin-film transistor liquid crystal display (TFT-LCD) wastewater. (United States)

    Lei, C N; Whang, L M; Lin, H L


    The amount of pollutants produced during manufacturing processes of TFT-LCD (thin-film transistor liquid crystal display) substantially increases due to an increasing production of the opto-electronic industry in Taiwan. The total amount of wastewater from TFT-LCD manufacturing plants is expected to exceed 200,000 CMD in the near future. Typically, organic solvents used in TFT-LCD manufacturing processes account for more than 33% of the total TFT-LCD wastewater. The main components of these organic solvents are composed of the stripper (dimethyl sulphoxide (DMSO) and monoethanolamine (MEA)), developer (tetra-methyl ammonium hydroxide (TMAH)) and chelating agents. These compounds are recognized as non-or slow-biodegradable organic compounds and little information is available regarding their biological treatability. In this study, the performance of an A/O SBR (anoxic/oxic sequencing batch reactor) treating synthetic TFT-LCD wastewater was evaluated. The long-term experimental results indicated that the A/O SBR was able to achieve stable and satisfactory removal performance for DMSO, MEA and TMAH at influent concentrations of 430, 800, and 190 mg/L, respectively. The removal efficiencies for all three compounds examined were more than 99%. In addition, batch tests were conducted to study the degradation kinetics of DMSO, MEA, and TMAH under aerobic, anoxic, and anaerobic conditions, respectively. The organic substrate of batch tests conducted included 400 mg/L of DMSO, 250 mg/L of MEA, and 120 mg/L of TMAH. For DMSO, specific DMSO degradation rates under aerobic and anoxic conditions were both lower than 4 mg DMSO/g VSS-hr. Under anaerobic conditions, the specific DMSO degradation rate was estimated to be 14 mg DMSO/g VSS-hr, which was much higher than those obtained under aerobic and anoxic conditions. The optimum specific MEA and TMAH degradation rates were obtained under aerobic conditions with values of 26.5 mg MEA/g VSS-hr and 17.3 mg TMAH/g VSS

  1. Volume reflection efficiency for negative particles in bent crystals (United States)

    Biryukov, V. M.


    We suggest a formula for the efficiency of a single volume reflection of negatively charged particles in bent crystal planes and compare it to recent experiments at SLAC, MAMI and CERN with electrons and negative pions in the energy range from 0.855 to 150 GeV in Si crystals. We show that Lindhard reversibility rule provides sufficient basis for quantitative understanding of these experiments.

  2. Volume reflection efficiency for negative particles in bent crystals

    Directory of Open Access Journals (Sweden)

    V.M. Biryukov


    Full Text Available We suggest a formula for the efficiency of a single volume reflection of negatively charged particles in bent crystal planes and compare it to recent experiments at SLAC, MAMI and CERN with electrons and negative pions in the energy range from 0.855 to 150 GeV in Si crystals. We show that Lindhard reversibility rule provides sufficient basis for quantitative understanding of these experiments.

  3. Technological process and optimum design of organic materials vacuum pyrolysis and indium chlorinated separation from waste liquid crystal display panels. (United States)

    Ma, En; Xu, Zhenming


    In this study, a technology process including vacuum pyrolysis and vacuum chlorinated separation was proposed to convert waste liquid crystal display (LCD) panels into useful resources using self-design apparatuses. The suitable pyrolysis temperature and pressure are determined as 300°C and 50 Pa at first. The organic parts of the panels were converted to oil (79.10 wt%) and gas (2.93 wt%). Then the technology of separating indium was optimized by central composite design (CCD) under response surface methodology (RSM). The results indicated the indium recovery ratio was 99.97% when the particle size is less than 0.16 mm, the weight percentage of NH4Cl to glass powder is 50 wt% and temperature is 450°C. The research results show that the organic materials, indium and glass of LCD panel can be recovered during the recovery process efficiently and eco-friendly.

  4. Solar power conversion efficiency in modulated silicon nanowire photonic crystals (United States)

    Deinega, Alexei; John, Sajeev


    It is suggested that using only 1 μm of silicon, sculpted in the form of a modulated nanowire photonic crystal, solar power conversion efficiency in the range of 15%-20% can be achieved. Choosing a specific modulation profile provides antireflection, light trapping, and back-reflection over broad angles in targeted spectral regions for high efficiency power conversion without solar tracking. Solving both Maxwell's equations in the 3D photonic crystal and the semiconductor drift-diffusion equations in each nanowire, we identify optimal junction and contact geometries and study the influence of the nanowire surface curvature on solar cell efficiency. We demonstrate that suitably modulated nanowires enable 20% efficiency improvement over their straight counterparts made of an equivalent amount of silicon. We also discuss the efficiency of a tandem amorphous and crystalline silicon nanowire photonic crystal solar cell. Opportunities for "hot carrier" collection and up-conversion of infrared light, enhanced by photonic crystal geometry, facilitate further improvements in power efficiency.

  5. The (unsuitability of modern liquid crystal displays (LCDs for vision research

    Directory of Open Access Journals (Sweden)

    Masoud eGhodrati


    Full Text Available Psychophysical and physiological studies of vision have traditionally used cathode ray tube (CRT monitors to present stimuli. These monitors are no longer easily available, and liquid crystal display (LCD technology is continually improving; therefore, we characterised a number of LCD monitors to determine if newer models are suitable replacements for CRTs in the laboratory. We compared the spatial and temporal characteristics of a CRT with five LCDs, including monitors designed with vision science in mind (ViewPixx and Display++, prosumer gaming monitors, and a consumer-grade LCD. All monitors had sufficient contrast, luminance range and reliability to support basic vision experiments with static images. However, the luminance of all LCDs depended strongly on viewing angle, which in combination with the poor spatial uniformity of all monitors except the VPixx, caused up to 80% drops in effective luminance in the periphery during central fixation. Further, all monitors showed significant spatial dependence, as the luminance of one area was modulated by the luminance of other areas. These spatial imperfections are most pronounced for experiments that use large or peripheral visual stimuli. In the temporal domain, the gaming LCDs were unable to generate reliable luminance patterns; one was unable to reach the requested luminance within a single frame whereas in the other the luminance of one frame affected the luminance of the next frame. The VPixx and Display++ were less affected by these problems, and had good temporal properties provided stimuli were presented for 2 or more frames. Of the consumer-grade and gaming displays tested, and if problems with spatial uniformity are taken into account, the Eizo FG2421 is the most suitable alternative to CRTs. The specialized ViewPixx performed best among all the tested LCDs, followed closely by the Display++; both are good replacements for a CRT, provided their spatial imperfections are considered.

  6. Improvement and efficient display of Bacillus thuringiensis toxins on M13 phages and ribosomes. (United States)

    Pacheco, Sabino; Cantón, Emiliano; Zuñiga-Navarrete, Fernando; Pecorari, Frédéric; Bravo, Alejandra; Soberón, Mario


    Bacillus thuringiensis (Bt) produces insecticidal proteins that have been used worldwide in the control of insect-pests in crops and vectors of human diseases. However, different insect species are poorly controlled by the available Bt toxins or have evolved resistance to these toxins. Evolution of Bt toxicity could provide novel toxins to control insect pests. To this aim, efficient display systems to select toxins with increased binding to insect membranes or midgut proteins involved in toxicity are likely to be helpful. Here we describe two display systems, phage display and ribosome display, that allow the efficient display of two non-structurally related Bt toxins, Cry1Ac and Cyt1Aa. Improved display of Cry1Ac and Cyt1Aa on M13 phages was achieved by changing the commonly used peptide leader sequence of the coat pIII-fusion protein, that relies on the Sec translocation pathway, for a peptide leader sequence that relies on the signal recognition particle pathway (SRP) and by using a modified M13 helper phage (Phaberge) that has an amber mutation in its pIII genomic sequence and preferentially assembles using the pIII-fusion protein. Also, both Cry1Ac and Cyt1Aa were efficiently displayed on ribosomes, which could allow the construction of large libraries of variants. Furthermore, Cry1Ac or Cyt1Aa displayed on M13 phages or ribosomes were specifically selected from a mixture of both toxins depending on which antigen was immobilized for binding selection. These improved systems may allow the selection of Cry toxin variants with improved insecticidal activities that could counter insect resistances.

  7. Rigorous analysis of an electric-field-driven liquid crystal lens for 3D displays

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bong-Sik; Lee, Seung-Chul; Park, Woo-Sang [Inha University, Incheon (Korea, Republic of)


    We numerically analyzed the optical performance of an electric field driven liquid crystal (ELC) lens adopted for 3-dimensional liquid crystal displays (3D-LCDs) through rigorous ray tracing. For the calculation, we first obtain the director distribution profile of the liquid crystals by using the Erickson-Leslie motional equation; then, we calculate the transmission of light through the ELC lens by using the extended Jones matrix method. The simulation was carried out for a 9 view 3D-LCD with a diagonal of 17.1 inches, where the ELC lens was slanted to achieve natural stereoscopic images. The results show that each view exists separately according to the viewing position at an optimum viewing distance of 80 cm. In addition, our simulation results provide a quantitative explanation for the ghost or blurred images between views observed from a 3D-LCD with an ELC lens. The numerical simulations are also shown to be in good agreement with the experimental results. The present simulation method is expected to provide optimum design conditions for obtaining natural 3D images by rigorously analyzing the optical functionalities of an ELC lens.

  8. Corelli: Efficient single crystal diffraction with elastic discrimination

    Indian Academy of Sciences (India)

    Stephan Rosenkranz; Raymond Osborn


    Single crystal diffuse scattering provides one of the most powerful probes of short-range correlations on the 1-100 nm scale, which often are responsible for the extreme field response of many emerging phenomena of great interest. Accurate modeling of such complex disorder from diffuse scattering data however puts stringent experimental demands, requiring measurements over large volumes of reciprocal space with sufficient momentum and energy resolution. Here, we discuss the potential of the cross-correlation technique for efficient measurement of single crystal diffuse scattering with energy discrimination, as will be implemented in a novel instrument, Corelli. Utilizing full experiment simulations, we show that this technique readily leads up to a fifty-fold gain in efficiency, as compared to traditional methods, for measuring single crystal diffuse scattering over volumes of reciprocal space with elastic discrimination.

  9. Using channelized Hotelling observers to quantify temporal effects of medical liquid crystal displays on detection performance (United States)

    Platiša, Ljiljana; Goossens, Bart; Vansteenkiste, Ewout; Badano, Aldo; Philips, Wilfried


    Clinical practice is rapidly moving in the direction of volumetric imaging. Often, radiologists interpret these images in liquid crystal displays at browsing rates of 30 frames per second or higher. However, recent studies suggest that the slow response of the display can compromise image quality. In order to quantify the temporal effect of medical displays on detection performance, we investigate two designs of a multi-slice channelized Hotelling observer (msCHO) model in the task of detecting a single-slice signal in multi-slice simulated images. The design of msCHO models is inspired by simplifying assumptions about how humans observe while viewing in the stack-browsing mode. For comparison, we consider a standard CHO applied only on the slice where the signal is located, recently used in a similar study. We refer to it as a single-slice CHO (ssCHO). Overall, our results confirm previous findings that the slow response of displays degrades the detection performance of the observers. More specifically, the observed performance range of msCHO designs is higher compared to the ssCHO suggesting that the extent and rate of degradation, though significant, may be less drastic than previously estimated by the ssCHO. Especially, the difference between msCHO and ssCHO is more significant for higher browsing speeds than for slow image sequences or static images. This, together with their design criteria driven by the assumptions about humans, makes the msCHO models promising candidates for further studies aimed at building anthropomorphic observer models for the stack-mode image presentation.

  10. Multi-wavelength sensitive holographic polymer dispersed liquid crystal grating applied within image splitter for autostereoscopic display (United States)

    Zheng, Jihong; Wang, Kangni; Gao, Hui; Lu, Feiyue; Sun, Lijia; Zhuang, Songlin


    Multi-wavelength sensitive holographic polymer dispersed liquid crystal (H-PDLC) grating and its application within image splitter for autostereoscopic display are reported in this paper. Two initiator systems consisting of photoinitiator, Methylene Blue and coinitiator, p-toluenesulfonic acid as well as photoinitiator, Rose Bengal and coinitiator, Nphenylglycine are employed. We demonstrate that Bragg gratings can be formed in this syrup polymerized under three lasers simultaneously including 632.8nm from He-Ne laser, 532nm from Verdi solid state laser, and 441.6nm from He- Cd laser. The diffraction efficiency of three kinds of gratings with different exposure wavelength are 57%, 75% and 33%, respectively. The threshold driving voltages of those gratings are 2.8, 3.05, and 2.85 V/μm, respectively. We also present the results for the feasibility of this proposed H-PDLC grating applied into image splitter without color dispersion for autostereoscopic display according to experimental splitting effect.

  11. Efficient coupling to slow light photonic crystal waveguide (United States)

    Khan, Md Shofiqul Islam; Devarapu, Ganga Chinna Rao; O'Faolain, Liam


    Slow light photonic crystal waveguides (PCWs) have been the subject of intensive study due to their potential for on-chip applications such as optical buffers and the enhancement of nonlinear phenomenon. However, due to high group velocity mismatch between the strip waveguide and the slow light waveguide efficient coupling of light is challenging. The coupling efficiency is also very sensitive to the truncation at the interface between the two waveguides. This sensitivity can be removed and light can efficiently be coupled from the strip waveguide to the slow light waveguide by adding an intermediate photonic crystal waveguide (or coupler) that operates at a group index of ˜ 5. Several designs have been proposed for couplers to obtain higher coupling efficiency within the desired group index range. We have studied uniaxial stretched couplers in which the lattice constant is stretched in the direction of propagation by 10-50 nm in the coupler region. Using a Finite Difference Time Domain (FDTD) Simulation Method that allows the extraction of the group index, we have observed 8.5 dB improvement in the coupling efficiency at the group index of 30. Efficient coupling is dominantly determined by the band edge position of the coupler region and maximum transmission efficiency is limited by the maximum transmission of the coupler PCW. If the band edge of coupler PCW is sufficiently red shifted relative to the band edge of the slow light PCW then higher coupling efficiency can be achieved.

  12. Highly efficient narrow-band green and red phosphors enabling wider color-gamut LED backlight for more brilliant displays. (United States)

    Wang, Le; Wang, Xiaojun; Kohsei, Takahashi; Yoshimura, Ken-ichi; Izumi, Makoto; Hirosaki, Naoto; Xie, Rong-Jun


    In this contribution, we propose to combine both narrow-band green (β-sialon:Eu(2+)) and red (K(2)SiF(6):Mn(4+)) phosphors with a blue InGaN chip to achieve white light-emitting diodes (wLEDs) with a large color gamut and a high efficiency for use as the liquid crystal display (LCD) backlighting. β-sialon:Eu(2+), prepared by a gas-pressure sinteing technique, has a peak emission at 535 nm, a full width at half maximum (FWHM) of 54 nm, and an external quantum efficiency of 54.0% under the 450 nm excitation. K(2)SiF(6):Mn(4+) was synthesized by a twe-step co-precipitation methods, and exhibits a sharp line emission spectrum with the most intensified peak at 631 nm, a FWHM of ~3 nm, and an external quantum efficiency of 54.5%. The prepared three-band wLEDs have a high color temperature of 11,184 - 13,769 K (i.e., 7,828 - 8,611 K for LCD displays), and a luminous efficacy of 91 - 96 lm/W, measured under an applied current of 120 mA. The color gamut defined in the CIE 1931 and CIE 1976 color spaces are 85.5 - 85.9% and 94.3 - 96.2% of the NTSC stanadard, respectively. These optical properties are better than those phosphor-cpnverted wLED backlights using wide-band green or red phosphoprs, suggesting that the two narrow-band phosphors investigated are the most suitable luminescent materials for achieving more bright and vivid displays.

  13. Enhanced contrast ratio of homogeneously aligned liquid crystal displays by controlling the surface-anchoring strength

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Young Jin; Woo, Chang Woo; Oh, Sang Hoon; Mukherjee, Amrita; Lee, Seung Hee [Department of BIN Fusion Technology and Department of Polymer Nano-Science and Technology, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Baek, Ji Ho; Kim, Kyeong Jin; Yang, Myung Su, E-mail: [Panel Performance Department, LG Display Co., Ltd., Paju, Gyeonggi-do 413-811 (Korea, Republic of)


    The dark state of homogeneously aligned liquid crystal displays (LCDs) associated with the in-plane switching of a LC director depends on their molecular ordering. We propose a new approach to reduce the light leakage in the dark state of homogeneously aligned LCDs. A very small amount of reactive mesogen (RM) is mixed with the LC material and polymerized at room temperature and also at a low temperature (-20 {sup 0}C) to strengthen the surface-anchoring energy. The contrast ratio of the low-temperature cured cell is improved by about 50% over that of the pure LC cell and the room temperature cured RM-mixed LC cell due to an enhanced order parameter.

  14. A liquid crystal display with consistent moving image quality regardless of viewing angles (United States)

    Kim, Jong-Man; Kim, Seung-Ryul; Kim, Jongbin; Kim, Minkoo; Lee, Seung-Woo


    This paper proposes a new overdrive (OD) technology to precisely compensate for the viewing angle dependent characteristics of LCDs. This paper reports that optical response of liquid crystal displays (LCDs) is considerably dependent on viewing angles for the first time. The new OD technology applies different OD look-up tables (LUTs) depending on the viewing angles. In addition, we combine a new OD technology with an eye tracker that is usually adopted for autostereoscopic 3D LCD systems. The application results show that a new OD technology improves the motion image quality perfectly regardless of viewing angles. We expect that our proposed method will definitely enable the LCD products to have consistent motion image quality regardless of viewing angles.

  15. Hydrometallurgical Recovery of Indium from Flat-Panel Displays of Spent Liquid Crystal Televisions (United States)

    Inoue, Katsutoshi; Alam, Shafiq


    A recovery process for indium from waste liquid crystal display panels was developed on the basis of hydrometallurgical technology. The powdered sample was leached with 3 M HCl to extract its various metal constituents (indium, aluminum, tin, etc.). The mutual separation and subsequent recovery of the dissolved metals was achieved using two column adsorption tests: The first column was packed with a porous resin impregnated with Aliquat 336, a commercially available solvent extraction reagent based on a quaternary ammonium compound, and the resin contained in the second column was impregnated with Cyanex 923, also a commercially available solvent extraction reagent based on trialkylphosphine oxide. In the first column, tin, iron, and zinc were removed from the leach liquor. In the second column, only indium was selectively recovered. The metal ions trapped in these columns were eluted with 0.1 M H2SO4, yielding a solution purified indium solution with a concentration 10 times that of the feed solution.

  16. Graphene oxide liquid crystals: synthesis, phase transition, rheological property, and applications in optoelectronics and display (United States)

    Lin, Feng; Tong, Xin; Wang, Yanan; Bao, Jiming; Wang, Zhiming M.


    Graphene oxide (GO) liquid crystals (LCs) are macroscopically ordered GO flakes dispersed in water or polar organic solvents. Since the first report in 2011, GO LCs have attracted considerable attention for their basic properties and potential device applications. In this review, we summarize recent developments and present a comprehensive understanding of GO LCs via many aspects ranging from the exfoliation of GO flakes from graphite, to phases and phase transitions under various conditions, the orientational responses of GO under external magnetic and electric fields, and finally Kerr effect and display applications. The emphasis is placed on the unique and basic properties of GO and their ordered assembly. We will also discuss challenges and issues that need to be overcome in order to gain a more fundamental understanding and exploit full device potentials of GO LCs.

  17. Novel cell parameter determination of a twisted-nematic liquid crystal display

    Institute of Scientific and Technical Information of China (English)

    Huang Xia; Jing Hai; Fu Guo-Zhu


    In this paper a novel method is proposed to determine the cell parameters including the twist angle, optic retardation and rubbing direction of twisted-nematic liquid crystal displays (TNLCD) by rotating the TNLCD. It is a single-wavelength method. Because using subtraction equation of transmittance as curve fitting equation, the influence of the light from environment and the absorption by polarizer, the sample of TNLCD and analyser on the transmittance is eliminated. Accurate results can also be obtained in imperfect darkness. By large numbers of experiments, we found that not only the experimental setup is quite simple and can be easily adopted to be carried out, but also the results are accurate.

  18. Colorimetric characterization of liquid crystal display using an improved two-stage model

    Institute of Scientific and Technical Information of China (English)

    Yong Wang; Haisong Xu


    @@ An improved two-stage model of colorimetric characterization for liquid crystal display (LCD) was proposed. The model included an S-shape nonlinear function with four coefficients for each channel to fit the Tone reproduction curve (TRC), and a linear transfer matrix with black-level correction. To compare with the simple model (SM), gain-offset-gain (GOG), S-curve and three-one-dimensional look-up tables (3-1D LUTs) models, an identical LCD was characterized and the color differences were calculated and summarized using the set of 7 × 7 × 7 digital-to-analog converter (DAC) triplets as test data. The experimental results showed that the model was outperformed in comparison with the GOG and SM ones, and near to that of the S-curve model and 3-1D LUTs method.

  19. Pyrolysis characteristics and pyrolysis products separation for recycling organic materials from waste liquid crystal display panels

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruixue; Xu, Zhenming, E-mail:


    Highlights: • Pyrolysis characteristics are conducted for a better understanding of LCDs pyrolysis. • Optimum design is developed which is significant to guide the further industrial process. • Acetic acid and TPP are recycled and separated. - Abstract: Waste liquid crystal display (LCD) panels mainly contain inorganic materials (glass substrate with indium-tin oxide film), and organic materials (polarizing film and liquid crystal). The organic materials should be removed beforehand since the organic matters would hinder the indium recycling process. In the present study, pyrolysis process is used to remove the organic materials and recycle acetic as well as and triphenyl phosphate (TPP) from waste LCD panels in an environmental friendly way. Several highlights of this study are summarized as follows: (i) Pyrolysis characteristics and pyrolysis kinetics analysis are conducted which is significant to get a better understanding of the pyrolysis process. (ii) Optimum design is developed by applying Box–Behnken Design (BBD) under response surface methodology (RSM) for engineering application which is significant to guide the further industrial recycling process. The oil yield could reach 70.53 wt% and the residue rate could reach 14.05 wt% when the pyrolysis temperature is 570 °C, nitrogen flow rate is 6 L min{sup −1} and the particle size is 0.5 mm. (iii) Furthermore, acetic acid and TPP are recycled, and then separated by rotary evaporation, which could reduce the consumption of fossil energy for producing acetic acid, and be reused in electronics manufacturing industry.

  20. Pyrolysis characteristics and pyrolysis products separation for recycling organic materials from waste liquid crystal display panels. (United States)

    Wang, Ruixue; Xu, Zhenming


    Waste liquid crystal display (LCD) panels mainly contain inorganic materials (glass substrate with indium-tin oxide film), and organic materials (polarizing film and liquid crystal). The organic materials should be removed beforehand since the organic matters would hinder the indium recycling process. In the present study, pyrolysis process is used to remove the organic materials and recycle acetic as well as and triphenyl phosphate (TPP) from waste LCD panels in an environmental friendly way. Several highlights of this study are summarized as follows: (i) Pyrolysis characteristics and pyrolysis kinetics analysis are conducted which is significant to get a better understanding of the pyrolysis process. (ii) Optimum design is developed by applying Box-Behnken Design (BBD) under response surface methodology (RSM) for engineering application which is significant to guide the further industrial recycling process. The oil yield could reach 70.53 wt% and the residue rate could reach 14.05 wt% when the pyrolysis temperature is 570 °C, nitrogen flow rate is 6 L min(-1) and the particle size is 0.5 mm. (iii) Furthermore, acetic acid and TPP are recycled, and then separated by rotary evaporation, which could reduce the consumption of fossil energy for producing acetic acid, and be reused in electronics manufacturing industry. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Pyrolysis mechanism for recycle renewable resource from polarizing film of waste liquid crystal display panels. (United States)

    Wang, Ruixue; Xu, Zhenming


    Liquid crystal display (LCD) panels mainly consist of polarizing film, liquid crystal and glass substrates. In this study, a novel pyrolysis model and a pyrolysis mechanism to recover the reusable resource from polarizing film of waste LCD panels was proposed. Polarizing film and its major components, such as cellulose triacetate (TAC) and polyvinyl alcohol (PVA) were pyrolyzed, respectively, to model the pyrolysis process. The pyrolysis process mainly generated a large ratio of oil, a few gases and a little residue. Acetic acid was the main oil product and could be easily recycled. The pyrolysis mechanism could be summarized as follows: (i) TAC, the main component of polarizing film, was heated and generated active TAC with a low polymerization, and then decomposed into triacetyl-d-glucose. (ii) Some triacetyl-d-glucose generated triacetyl-d-mannosan and its isomers through an intramolecular dehydration, while most triacetyl-d-glucose generated the main oil product, namely acetic acid, through a six-member cyclic transition state. (iii) Meanwhile, other products formed through a series of bond cleavage, dehydration, dehydrogenation, interesterification and Diels-Alder cycloaddition. This study could contribute significantly to understanding the polarizing film pyrolysis performance and serve as guidance for the future technological parameters control of the pyrolysis process.

  2. Viewing angle switching of liquid crystal display using fringe-field switching to control off-axis phase retardation

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Young Jin; Kim, Jin Ho; Her, Jung Hwa; Lee, Seung Hee [Polymer BIN Fusion Research Center, Department of Polymer Nano-Science and Technology, Chonbuk National University, Chonju, Chonbuk 561-756 (Korea, Republic of); Park, Kyoung Ho; Lee, Joun Ho; Kim, Byeong Koo [Mobile Product Development Department, LG Display Company, Ltd, Gumi, Gyungbuk 730-350 (Korea, Republic of); Kang, Wan-Seok; Lee, Gi-Dong, E-mail:, E-mail: [Department of Electronics Engineering, Dong-A University, Pusan 604-714 (Korea, Republic of)


    A viewing angle switchable liquid crystal display associated with fringe-field switching mode is proposed. In the device, one pixel is composed of a main pixel and a sub-pixel, in which both pixels are formed to generate a fringe electric field. However, the field directions are different from each other so that in the main pixel, the fringe field rotates the liquid crystal for displaying the main image, whereas it controls only the tilt angle of the liquid crystal without rotating in the sub-pixel region. In this way, phase retardation to cause leakage of light at the off-normal axis can be generated in the sub-pixel, and by utilizing the light, the main displayed image in the normal direction can be blocked in the oblique viewing direction.

  3. The influence of the conical incidence on the waveguide-type colour-separating backlight for liquid crystal display (United States)

    Luo, Ji; Wang, Wenfeng


    The lightguide assisted by diffraction gratings is used to implement colour-separating backlight for Liquid Crystal Display (LCD). In the configuration, the light incidence angle is required to be a precise designed one. However, the light incidence is conical always. In this paper, by rigorous coupled wave theory, the influence of conical input on the colour-separating backlight is investigated. It shows that, when the azimuthal angle of the light increases, the diffraction efficiency could be enhanced by a factor of 2, which means that the conical input will benefit the diffraction efficiency of the lightguide. However, it also leads to a larger output spot area at the same time, which could result in the mixing of RGB pix. When the azimuthal angle is smaller than 12°, the maximum diffraction angles of RGB light can be completely separated, which means that, with a designed distance or with an assisted micro-lens layer between the grating and the pix layer, the RGB light can reach their corresponding pix. The influence of the conical input on the polarized light is also investigated. The conical input will result in the output with composite polarization, which, in principle, disables the use of polarized light source in LCD.

  4. Prediction of Giant Thermoelectric Efficiency in Crystals with Interlaced Nanostructure. (United States)

    Puzyrev, Y S; Shen, X; Pantelides, S T


    We present a theoretical study of the thermoelectric efficiency of "interlaced crystals", recently discovered in hexagonal-CuInS2 nanoparticles. Interlaced crystals are I-III-VI2 or II-IV-V2 tetrahedrally bonded compounds. They have a perfect Bravais lattice in which the two cations have an infinite set of possible ordering patterns within the cation sublattice. The material comprises nanoscale interlaced domains and phases with corresponding boundaries. Here we employ density functional theory and large-scale molecular dynamics calculations based on model classical potentials to demonstrate that the phase and domain boundaries are effective phonon scatterers and greatly suppress thermal conductivity. However, the absence of both structural defects and strain in the interlaced material results in a minimal effect on electronic properties. We predict an increase of thermal resistivity of up to 2 orders of magnitude, which makes interlaced crystals an exceptional candidate for thermoelectric applications.

  5. Monoclonal surface display SELEX for simple, rapid, efficient, and cost-effective aptamer enrichment and identification. (United States)

    Zhu, Zhi; Song, Yanling; Li, Cong; Zou, Yuan; Zhu, Ling; An, Yuan; Yang, Chaoyong James


    A novel method, monoclonal surface display SELEX (MSD-SELEX), has been designed for simple, rapid, efficient, and cost-effective enrichment and identification of aptamers from a library of monoclonal DNA-displaying beads produced via highly parallel single-molecule emulsion PCR. The approach was successfully applied for the identification of high-affinity aptamers that bind specifically to different types of targets, including cancer biomarker protein EpCAM and small toxin molecule aflatoxin B1. Compared to the conventional sequencing-chemical synthesis-screening work flow, MSD-SELEX avoids large-scale DNA sequencing, expensive and time-consuming DNA synthesis, and labor-intensive screening of large populations of candidates, thus offering a new approach for simple, rapid, efficient, and cost-effective aptamer identification for a wide variety of applications.

  6. Need for liquid-crystal display monitors having the capability of rendering higher than 8 bits in display-bit depth. (United States)

    Hiwasa, Takeshi; Morishita, Junji; Hatanaka, Shiro; Ohki, Masafumi; Toyofuku, Fukai; Higashida, Yoshiharu


    Our purpose in this study was to examine the potential usefulness of liquid-crystal display (LCD) monitors having the capability of rendering higher than 8 bits in display-bit depth. An LCD monitor having the capability of rendering 8, 10, and 12 bits was used. It was calibrated to the grayscale standard display function with a maximum luminance of 450 cd/m(2) and a minimum of 0.75 cd/m(2). For examining the grayscale resolution reported by ten observers, various simple test patterns having two different combinations of luminance in 8, 10, and 12 bits were randomly displayed on the LCD monitor. These patterns were placed on different uniform background luminance levels, such as 0, 50, and 100%, for maximum luminance. All observers participating in this study distinguished a smaller difference in luminance than one gray level in 8 bits irrespective of background luminance levels. As a result of the adaptation processes of the human visual system, observers distinguished a smaller difference in luminance as the luminance level of the test pattern was closer to the background. The smallest difference in luminance that observers distinguished was four gray levels in 12 bits, i.e., one gray level in 10 bits. Considering the results obtained by use of simple test patterns, medical images should ideally be displayed on LCD monitors having 10 bits or greater so that low-contrast objects with small differences in luminance can be detected and for providing a smooth gradation of grayscale.

  7. Efficient low-temperature thermophotovoltaic emitters from metallic photonic crystals. (United States)

    Nagpal, Prashant; Han, Sang Eon; Stein, Andreas; Norris, David J


    We examine the use of metallic photonic crystals as thermophotovoltaic emitters. We coat silica woodpile structures, created using direct laser writing, with tungsten or molybdenum. Optical reflectivity and thermal emission measurements near 650 degrees C demonstrate that the resulting structures should provide efficient emitters at relatively low temperatures. When matched to InGaAsSb photocells, our structures should generate over ten times more power than solid emitters while having an optical-to-electrical conversion efficiency above 32%. At such low temperatures, these emitters have promise not only in solar energy but also in harnessing geothermal and industrial waste heat.

  8. Applying Ant Colony Algorithm and Neural Network Model to Color Deviation Defect Detection in Liquid Crystal Displays

    Directory of Open Access Journals (Sweden)

    Hong-Dar Lin


    Full Text Available Thin Film Transistor Liquid Crystal Display (TFT-LCD has excellent properties such as lower voltage to start and less occupied space if comparing with traditional Cathode-Ray Tube (CRT. But screen flaw points and display color deviation defects on image display exist in TFT-LCD products. This research proposes a new automated visual inspection method to solve the problems. We first use multivariate Hotelling T2 statistic for integrating coordinates of color models to construct a T2 energy diagram for inspecting defects and controlling patterns in TFT-LCD display images. An Ant Colony based approach that integrates computer vision techniques is developed to detect the flaw point defects. Then, Back Propagation Network (BPN model is proposed to inspect small deviation defects of the LCD display colors. Experimental results show the proposed system can provide good effects and practicality.

  9. Ray-tracing simulations of liquid-crystal gradient-index lenses for three-dimensional displays

    NARCIS (Netherlands)

    Sluijter, M.; Herzog, A.; De Boer, D.K.G.; Krijn, M.P.C.M.; Urbach, P.H.


    For the first time, to our knowledge, we report ray-tracing simulations of an advanced liquid-crystal gradientindex lens structure for application in switchable two-dimensional/three-dimensional (3D) autostereoscopic displays. We present ray-tracing simulations of the angular-dependent lens action.

  10. Study on the waste liquid crystal display treatment: focus on the resource recovery. (United States)

    Wang, Xinying; Lu, Xuebin; Zhang, Shuting


    A process combined pyrolysis and acid immersion was proposed in this study to dispose the hazardous liquid crystal display (LCD) waste for recovering valuable resources. The thermogravimetric (TG) analysis and fixed bed pyrolysis were investigated for the polarizing film that was separated from LCD. The results suggested the liquid product mainly contained acids, esters and aromatics should be upgraded such as hydrotreating process before used as industrial feedstock or fuel source. The gaseous product mainly consisted of H(2), CO, CO(2) and CH(4) can be used as a valuable fuel. The sulfuric acid immersion experiments were studied for recovering indium from the LCD glass after stripping the polarizing film. Central composite design (CCD) under response surface methodology (RSM) was used to optimize the acid immersion process and the results indicated the indium recovery can be fitted based on the actual value to a polynomial quadratic equation and the temperature was more essential factor than time and acid concentration in the studied ranges. The optimum processing condition was obtained with time 42.2 min, temperature 65.6 °C and acid concentration 0.6 mol/L. Under the optimal conditions, the indium recovery was close to 100%.

  11. Automated optical inspection of liquid crystal display anisotropic conductive film bonding (United States)

    Ni, Guangming; Du, Xiaohui; Liu, Lin; Zhang, Jing; Liu, Juanxiu; Liu, Yong


    Anisotropic conductive film (ACF) bonding is widely used in the liquid crystal display (LCD) industry. It implements circuit connection between screens and flexible printed circuits or integrated circuits. Conductive microspheres in ACF are key factors that influence LCD quality, because the conductive microspheres' quantity and shape deformation rate affect the interconnection resistance. Although this issue has been studied extensively by prior work, quick and accurate methods to inspect the quality of ACF bonding are still missing in the actual production process. We propose a method to inspect ACF bonding effectively by using automated optical inspection. The method has three steps. The first step is that it acquires images of the detection zones using a differential interference contrast (DIC) imaging system. The second step is that it identifies the conductive microspheres and their shape deformation rate using quantitative analysis of the characteristics of the DIC images. The final step is that it inspects ACF bonding using a back propagation trained neural network. The result shows that the miss rate is lower than 0.1%, and the false inspection rate is lower than 0.05%.

  12. Comparison of viewing angle and observer performances in different types of liquid-crystal display monitors. (United States)

    Hatanaka, Shiro; Morishita, Junji; Hiwasa, Takeshi; Dogomori, Kiyoshi; Toyofuku, Fukai; Ohki, Masafumi; Higashida, Yoshiharu


    It is known that the performance of liquid-crystal display (LCD) monitors, such as the luminance and contrast ratio, is dependent on the viewing angle. Our purpose in this study was to compare the angular performance and the effect on observer performance of different types of LCD monitors. The luminance performance and contrast ratio as a function of viewing angle (-60 degrees to 60 degrees) in each direction for two types of LCD monitors, namely, a general-purpose LCD monitor and one especially designed for medical use, were measured in this study. Furthermore, the observer performance at various viewing angles in the horizontal direction for a medical-grade LCD monitor was investigated by eight observers based on a contrast-detail diagram. The two types of LCD monitors showed notable variations in luminance and contrast ratio as a function of the viewing angle. Acceptable viewing angles in terms of the contrast ratio were much smaller in each direction than those for nominal viewing angles in the specifications provided by the manufacturers, and those for the medical-grade LCD monitor in the horizontal and vertical directions were broader than those of the general-purpose LCD monitor. There was no significant difference in observer performance between 0 degrees and 40 degrees. On the other hand, our results showed a statistically significant difference in observer performance between 0 degrees and 60 degrees.

  13. Curved Ferroelectric Liquid Crystal Matrix Displays Driven by Field-Sequential-Color and Active-Matrix Techniques (United States)

    Fujikake, Hideo; Sato, Hiroto; Murashige, Takeshi; Fujisaki, Yoshihide; Kurita, Taiichiro; Furukawa, Tadahiro; Sato, Fumio

    This paper describes a curved field-sequential-color matrix display using fast-response ferroelectric liquid crystal. Black matrix and transparent electrode patterns were formed on a thin plastic substrate by a transfer method from a glass substrate. While a composite film of liquid crystal and micro-polymers of walls and fibers was formed between the flexible substrates by printing, laminating and curing processes of a solution of monomers and liquid crystal, the mechanical stability was enhanced by use of multi-functional monomers to form large display panels. The image pixels of the matrix panel were driven by an active matrix scheme using an external switch transistor array at a frequency of 180 Hz for intermittent three-primary-color backlight illumination. The flexible A4-paper-sized color display with 24 × 16 pixels and 60 Hz field frequency was demonstrated by illuminating it with sequential three-primary-color lights from light-emitting diodes of the backlight. Our display system is useful in various information displays because of its freedom of setting and location.

  14. High-efficiency photonic crystal narrowband thermal emitters (United States)

    Farfan, G. B.; Su, M. F.; Reda Taha, M. M.; El-Kady, I.


    Photonic crystals (PhC) are artificial structures fabricated with a periodicity in the dielectric function. This periodic electromagnetic potential results in creation of energy bandgaps where photon propagation is prohibited. PhC structures have promising use in thermal applications if optimized to operate at specific thermal emission spectrum. Here, novel utilization of optimized PhC's in thermal applications is presented. We demonstrate through numerical simulation the modification of the thermal emission spectrum by a metallic photonic crystal (PhC) to create high-efficiency multispectral thermal emitters. These emitters funnel radiation from a broad emission spectrum associated with a Plancklike distribution into a prescribed narrow emission band. A detailed quantitative evaluation of the spectral and power efficiencies of a PhC thermal emitter and its portability across infrared (IR) spectral bands are provided. We show an optimized tungsten PhC with a predominant narrow-band emission profile with an emitter efficiency that is more than double that of an ideal blackbody and ~65-75% more power-efficiency across the IR spectrum. We also report on using optimal three-dimensional Lincoln log photonic crystal (LL-PhC) emitters for thermophotovoltaic (TPV) generation as opposed to using a passive filtering approach to truncate the broadband thermal source emission to match the bandgap of a photovoltaic (PV) cell. The emitter performance is optimized for the 1-2μm PV band using different PhC materials, specifically copper, silver and gold. The use of the proposed PhC in TPV devices can produce significant energy savings not reported before. The optimal design of the PhC geometry is obtained by implementing a variety of optimization methods integrated with artificial intelligence (AI) algorithms.

  15. Ice crystal characterization in cirrus clouds: a sun-tracking camera system and automated detection algorithm for halo displays (United States)

    Forster, Linda; Seefeldner, Meinhard; Wiegner, Matthias; Mayer, Bernhard


    Halo displays in the sky contain valuable information about ice crystal shape and orientation: e.g., the 22° halo is produced by randomly oriented hexagonal prisms while parhelia (sundogs) indicate oriented plates. HaloCam, a novel sun-tracking camera system for the automated observation of halo displays is presented. An initial visual evaluation of the frequency of halo displays for the ACCEPT (Analysis of the Composition of Clouds with Extended Polarization Techniques) field campaign from October to mid-November 2014 showed that sundogs were observed more often than 22° halos. Thus, the majority of halo displays was produced by oriented ice crystals. During the campaign about 27 % of the cirrus clouds produced 22° halos, sundogs or upper tangent arcs. To evaluate the HaloCam observations collected from regular measurements in Munich between January 2014 and June 2016, an automated detection algorithm for 22° halos was developed, which can be extended to other halo types as well. This algorithm detected 22° halos about 2 % of the time for this dataset. The frequency of cirrus clouds during this time period was estimated by co-located ceilometer measurements using temperature thresholds of the cloud base. About 25 % of the detected cirrus clouds occurred together with a 22° halo, which implies that these clouds contained a certain fraction of smooth, hexagonal ice crystals. HaloCam observations complemented by radiative transfer simulations and measurements of aerosol and cirrus cloud optical thickness (AOT and COT) provide a possibility to retrieve more detailed information about ice crystal roughness. This paper demonstrates the feasibility of a completely automated method to collect and evaluate a long-term database of halo observations and shows the potential to characterize ice crystal properties.

  16. Ice crystal characterization in cirrus clouds: a sun-tracking camera system and automated detection algorithm for halo displays

    Directory of Open Access Journals (Sweden)

    L. Forster


    Full Text Available Halo displays in the sky contain valuable information about ice crystal shape and orientation: e.g., the 22° halo is produced by randomly oriented hexagonal prisms while parhelia (sundogs indicate oriented plates. HaloCam, a novel sun-tracking camera system for the automated observation of halo displays is presented. An initial visual evaluation of the frequency of halo displays for the ACCEPT (Analysis of the Composition of Clouds with Extended Polarization Techniques field campaign from October to mid-November 2014 showed that sundogs were observed more often than 22° halos. Thus, the majority of halo displays was produced by oriented ice crystals. During the campaign about 27 % of the cirrus clouds produced 22° halos, sundogs or upper tangent arcs. To evaluate the HaloCam observations collected from regular measurements in Munich between January 2014 and June 2016, an automated detection algorithm for 22° halos was developed, which can be extended to other halo types as well. This algorithm detected 22° halos about 2 % of the time for this dataset. The frequency of cirrus clouds during this time period was estimated by co-located ceilometer measurements using temperature thresholds of the cloud base. About 25 % of the detected cirrus clouds occurred together with a 22° halo, which implies that these clouds contained a certain fraction of smooth, hexagonal ice crystals. HaloCam observations complemented by radiative transfer simulations and measurements of aerosol and cirrus cloud optical thickness (AOT and COT provide a possibility to retrieve more detailed information about ice crystal roughness. This paper demonstrates the feasibility of a completely automated method to collect and evaluate a long-term database of halo observations and shows the potential to characterize ice crystal properties.

  17. Development of efficient RNA interference system using EGF-displaying phagemid particles

    Institute of Scientific and Technical Information of China (English)

    Hua JIANG; Xiu-mei CAI; Bi-zhi SHI; Jie ZHANG; Zong-hai LI; Jian-ren GU


    Aim:To develop an efficient RNA interference system using phagemid particles displaying the epidermal growth factor (EGF) ligand. Methods:pSilencer 1.0-siEGFP and pSilencer4.1-siAkt plasmids were constructed by gene clone technology. The modified helper phage genome (plasmid) M 13KO7EGFCT was used to pack-age phagemids, such as pSilencer 1.0-siEGFP and pSilencer4.1-siAkt. ELISA was used to quantify the titer of the progeny virus particles. Single-strand DNA was extracted and analyzed by agarose gel electrophoresis to evaluate the percentage of the phagemid particles. The expression level of the reporter gene enhanced green fluorescence protein (EGFP) was determined by transducing phagemid par-ticles packaging pSileneer 1.0-siEGFP into cells. The level of Akt gene expression in cells transduced phagemid particles packaging pSilencer4. 1-siAkt was exam-ined by Western blotting. Hydroxycamptothecin (HCPT) was used to enhance the gene transduction efficiency. Results:RNAi vectors pSilencer1.0-siEGFP and pSilencer4.1-siAkt were successfully constructed. Phagemid-encoding siRNA can be packaged efficiently. After the cells were infected by EGF displaying phagemid particles in the presence of HCPT, the expression of the target gene EGFPor Akt was substantially downregulated. Conclusion:Cell-targeted phagemid particles are efficient siRNA delivery vectors in the presence of HCPT.

  18. X-Ray Line Measurements with High Efficiency Bragg Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Pak, A; Gregori, G; Knight, J; Campbell, K; Landen, O; Glenzer, S


    We have studied the focusing properties of two highly oriented pyrolitic graphite (HOPG) spectrometers, which differ in the degree of the mosaic spread: ZYA with a low mosaic spread ({gamma}=0.4 degrees) and ZYH with a large mosaic spread ({gamma}=3.5 degrees). In order to assess the crystal performance for a variety of different experiments, various K{alpha} and K{beta} x-ray lines have been produced using a high-intensity ({approx}>10{sup 17} W/cm{sup 2}) short-pulse ({approx} 100 fs) laser beam focused onto Ti, V, Zn, and Cu foils. The measured spectral resolution of the HOPG crystals in both first and second order diffraction has been compared with theoretical predictions. Using known values for the peak reflectivity of HOPG crystals, we have also computed K{alpha} x-ray conversion efficiencies of Ti, V, Zn, and Cu. These results are important to estimate the optimal conditions under which different types of HOPG monochromators can be used for the detection of weak x-ray signals as the one encountered in x-ray Thomson/Compton scattering experiments.

  19. Realization of Field Sequential Color in Simple Matrix Antiferroelectric Liquid Crystal Displays by Utilizing Fast Pretransitional Response (United States)

    Suzuki, Yasushi; Chen, Guo-Ping; Manna, Uttam; Vij, Jagdish K.; Fukuda, Atsuo


    Simple matrix antiferroelectric liquid crystal displays (SM-AFLCDs) are prototyped to realize field sequential color (FSC) by utilizing the fast pretransitional response. The developed FSC-SM-AFLCDs will lead to the replacement of existing static driven FSC-SM-nematic-LCDs. Bright and clear color can be given to already market-acquired, black-and-white SM-LCDs of up to 1/64-duty and 3-in. diagonal size. To optimize the display performance, we analyze two important factors, the large pretransitional effect and the appropriate reset pulse, in terms of the interlayer interaction potential used in describing the field-induced transition of the antiferroelectric smectic phase.

  20. Compact Holographic Projection Display Using Liquid-Crystal-on-Silicon Spatial Light Modulator

    Directory of Open Access Journals (Sweden)

    Wei-Feng Hsu


    Full Text Available This paper presents a holographic projection display in which a phase-only spatial light modulator (SLM performs three functions: beam shaping, image display, and speckle reduction. The functions of beam shaping and image display are performed by dividing the SLM window into four sub-windows loaded with different diffractive phase elements (DPEs. The DPEs are calculated using a modified iterative Fourier transform algorithm (IFTA. The function of speckle reduction is performed using temporal integration of display images containing speckles. The speckle contrast ratio of the display image is 0.39 due to the integration of eight speckled images. The system can be extended to display full-color images also by using temporal addition of elementary color images. Because the system configuration needs only an SLM, a Fourier transform lens, and two mirrors, the system volume is very small, becoming a potential candidate for micro projectors.

  1. Directional backlight liquid crystal autostereoscopic display: technical challenges, research progress, and prospect (Conference Presentation) (United States)

    Fan, Hang; Li, Kunyang; Zhou, Yangui; Liang, Haowen; Wang, Jiahui; Zhou, Jianying


    Recent upsurge on virtual and augmented realities (VR and AR) has re-ignited the interest to the immerse display technology. The VR/AR technology based on stereoscopic display is believed in its early stage as glasses-free, or autostereoscopic display, will be ultimately adopted for the viewing convenience, visual comfort and for the multi-viewer purposes. On the other hand, autostereoscopic display has not yet received positive market response for the past years neither with stereoscopic displays using shutter or polarized glasses. We shall present the analysis on the real-world applications, rigid user demand, the drawbacks to the existing barrier- and lenticular lens-based LCD autostereoscopy. We shall emphasize the emerging autostereoscopic display, and notably on directional backlight LCD technology using a hybrid spatial- and temporal-control scenario. We report the numerical simulation of a display system using Monte-Carlo ray-tracing method with the human retina as the real image receiver. The system performance is optimized using newly developed figure of merit for system design. The reduced crosstalk in an autostereoscopic system, the enhanced display quality, including the high resolution received by the retina, the display homogeneity without Moiré- and defect-pattern, will be highlighted. Recent research progress including a novel scheme for diffraction-free backlight illumination, the expanded viewing zone for autostereoscopic display, and the novel Fresnel lens array to achieve a near perfect display in 2D/3D mode will be introduced. The experimental demonstration will be presented to the autostereoscopic display with the highest resolution, low crosstalk, Moiré- and defect- pattern free.

  2. High efficiency recovery and epitope specific sorting of an scFv yeast display library

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, Robert W.; Coleman, James R.; Miller, Keith D.; Feldhaus, Michael


    In order to more productively utilize the rich source of antigen specific reagents present in the previously described non-immune scFv yeast display library (Feldhaus et al., 2003) one must be able to efficiently isolate and characterize clones within the library. To this end, we have developed and validated a magnetic bead sorting technique utilizing the Miltenyi MacsTm system to recover greater than 90% of the antigen specific clones present in the library. In combination with flow cytometry, we rapidly reduced diversity and enriched for antigen specific clones in three rounds of selection. Furthermore, we demonstrate the use of pre-existing monoclonal antibodies (mAbs) for antigen labeling and subsequent flow cytometric sorting and characterization of epitope specific scFv. Combining these two improvements in library screening allowed isolation and characterization of 3 epitope specific scFv (including a previously uncharacterized epitope) to a 6 kd protein, epidermal growth factor EGF.

  3. Profiling of liquid crystal displays with Raman spectroscopy: Preprocessing of spectra.

    NARCIS (Netherlands)

    O. Stanimirovic; H.F.M. Boelens; A.J.G. Mank; H.C.J. Hoefsloot; A.K. Smilde


    Raman spectroscopy is applied for characterizing paintable displays. Few other options than Raman spectroscopy exist for doing so because of the liquid nature of functional materials. The challenge is to develop a method that can be used for estimating the composition of a single display cell on the

  4. Fine-pitch high-efficiency spatial optical modulator for mobile display applications (United States)

    Song, Jong Hyeong; Yun, Sang Kyeong; Kim, Hee Yeoun; An, Seungdo; Park, Heung Woo; Choi, Yoon Joon; Yurlov, Victor; Lapchuk, Anatoliy; Yang, Chung Mo; Lee, Sung Jun; Jang, Jae Wook; Lee, Ki Un; Woo, Ki Suk; Bourim, El M.


    Diffractive spatial optical modulators (SOM) with fine pitch pixel array were introduced for the mobile applications of laser projection display which requires the small volume, low power consumption and high optical efficiency. Micromechanical designs of piezoelectric (PZT) actuator and mirror ribbon structure were optimized for small volume, but keeping the same level of the other performance. Even though the same design rule and fabrication equipment were used for 10 um pitch SOM and 16 um pitch SOM, the optical efficiency of the fine pitch SOM was 78 % for the 0th order diffraction and is better than that of 16 um pitch SOM (73%). The full on/off contrast ratio has no difference between 10 um pitch and 16 um pitch SOM. All the optical characteristics coincide well with the theoretical estimations. High displacement of 500nm, which is enough to modulate the three Red, Green and Blue colors were achieved by the control of the thicknesses and stresses of constituent structural layers. It was found that the stress of Pt/PZT/Pt actuating layer was the main parameter affecting the initial gap height of the ribbon and also its displacement. For improving the optical properties of the SOM devices, the required ribbon-flatness could be achieved by applying a stress gradient on the SiN layer to compensate for the stress unbalance between Al mirror and SiN supprting layer. The temperature sensitive characteristics of the SOM device, which degrades the image quality, could be minimized by a mechanical compensation method using a thermal expansion effect of Si substrates. This concept could be applied in most of the bridge type MEMS structure. The most critical parameter which limit the SOM device lifetime was found to be the ribbon displacement degradation. By using a temperature accelerating lifetime measurement method based on the displacement degradation the estimated lifetime was more than 4,000 hrs and is of acceptable level in the mobile application. In short, the

  5. Projection displays (United States)

    Chiu, George L.; Yang, Kei H.


    Projection display in today's market is dominated by cathode ray tubes (CRTs). Further progress in this mature CRT projector technology will be slow and evolutionary. Liquid crystal based projection displays have gained rapid acceptance in the business market. New technologies are being developed on several fronts: (1) active matrix built from polysilicon or single crystal silicon; (2) electro- optic materials using ferroelectric liquid crystal, polymer dispersed liquid crystals or other liquid crystal modes, (3) micromechanical-based transducers such as digital micromirror devices, and grating light valves, (4) high resolution displays to SXGA and beyond, and (5) high brightness. This article reviews the projection displays from a transducer technology perspective along with a discussion of markets and trends.

  6. Efficient Liver Targeting by Polyvalent Display of a Compact Ligand for the Asialoglycoprotein Receptor. (United States)

    Sanhueza, Carlos A; Baksh, Michael M; Thuma, Benjamin; Roy, Marc D; Dutta, Sanjay; Préville, Cathy; Chrunyk, Boris A; Beaumont, Kevin; Dullea, Robert; Ammirati, Mark; Liu, Shenping; Gebhard, David; Finley, James E; Salatto, Christopher T; King-Ahmad, Amanda; Stock, Ingrid; Atkinson, Karen; Reidich, Benjamin; Lin, Wen; Kumar, Rajesh; Tu, Meihua; Menhaji-Klotz, Elnaz; Price, David A; Liras, Spiros; Finn, M G; Mascitti, Vincent


    A compact and stable bicyclic bridged ketal was developed as a ligand for the asialoglycoprotein receptor (ASGPR). This compound showed excellent ligand efficiency, and the molecular details of binding were revealed by the first X-ray crystal structures of ligand-bound ASGPR. This analogue was used to make potent di- and trivalent binders of ASGPR. Extensive characterization of the function of these compounds showed rapid ASGPR-dependent cellular uptake in vitro and high levels of liver/plasma selectivity in vivo. Assessment of the biodistribution in rodents of a prototypical Alexa647-labeled trivalent conjugate showed selective hepatocyte targeting with no detectable distribution in nonparenchymal cells. This molecule also exhibited increased ASGPR-directed hepatocellular uptake and prolonged retention compared to a similar GalNAc derived trimer conjugate. Selective release in the liver of a passively permeable small-molecule cargo was achieved by retro-Diels-Alder cleavage of an oxanorbornadiene linkage, presumably upon encountering intracellular thiol. Therefore, the multicomponent construct described here represents a highly efficient delivery vehicle to hepatocytes.

  7. Construction of a high efficiency copper adsorption bacterial system via peptide display and its application on copper dye polluted wastewater. (United States)

    Maruthamuthu, Murali Kannan; Nadarajan, Saravanan Prabhu; Ganesh, Irisappan; Ravikumar, Sambandam; Yun, Hyungdon; Yoo, Ik-Keun; Hong, Soon Ho


    For the construction of an efficient copper waste treatment system, a cell surface display strategy was employed. The copper adsorption ability of recombinant bacterial strains displaying three different copper binding peptides were evaluated in LB Luria-Bertani medium (LB), artificial wastewater, and copper phthalocyanine containing textile dye industry wastewater samples. Structural characteristics of the three peptides were also analyzed by similarity-based structure modeling. The best binding peptide was chosen for the construction of a dimeric peptide display and the adsorption ability of the monomeric and dimeric peptide displayed strains were compared. The dimeric peptide displayed strain showed superior copper adsorption in all three tested conditions (LB, artificial wastewater, and textile dye industry wastewater). When the strains were exposed to copper phthalocyanine dye polluted wastewater, the dimeric peptide display [543.27 µmol/g DCW dry cell weight (DCW)] showed higher adsorption of copper when compared with the monomeric strains (243.53 µmol/g DCW).

  8. Efficient multiband absorber based on 1D periodic metal-dielectric photonic crystals with a reflective substrate

    CERN Document Server

    Cui, Yanxia; He, Yingran; Hao, Yuying; Lin, Yinyue; Tian, Ximin; Xu, Ju; Ji, Ting; He, Sailing; Fang, Nicholas X


    We propose an efficient multiband absorber comprising a truncated one-dimensional periodic metal-dielectric photonic crystal and a reflective substrate. The reflective substrate is actually an optically thick metallic film. Such a planar device is easier to fabricate compared with the absorbers with complicated shapes. For a 4-unit cell device, all of the four absorption peaks can be optimized with efficiencies higher than 95%. Moreover, those absorption peaks are insensitive to both polarization and incident angle. The influences of the geometrical parameters along with the refractive index of the dielectric on the device performance are discussed as well. Furthermore, it is found that the number of absorption peaks within each photonic band exactly corresponds to the number of the unit cells because the truncated photonic crystal lattices have the function of selecting resonant modes. It is also displayed that the total absorption efficiency gradually increases when there are more metal-dielectric unit cell...

  9. UV durable colour pigment doped SmA liquid crystal composites for outdoor trans-reflective bi-stable displays (United States)

    Xu, H.; Davey, A. B.; Crossland, W. A.; Chu, D. P.


    High brightness trans-reflective bi-stable displays based on smectic A (SmA) liquid crystals (LCs) can have nearly perfect transparency in the clear state and very high reflection in the scattered state. Because the LC material in use is stable under UV radiation, this kind of displays can stand for strong day-light and therefore be ideal for outdoor applications from e-books to public signage and advertisement. However, the colour application has been limited because the traditional colourants in use are conventional dyes which are lack of UV stability and that their colours are easily photo bleached. Here we present a colour SmA display demonstrator using pigments as colourant. Mixing pigments with SmA LCs and maintain the desirable optical switching performance is not straightforward. We show here how it can be done, including how to obtain fine sized pigment nano-particles, the effects of particle size and size distribution on the display performance. Our optimized pigments/SmA compositions can be driven by a low frequency waveform (~101Hz) to a scattered state to exhibit colour while by a high frequency waveform (~103Hz) to a cleared state showing no colour. Finally, we will present its excellent UV life-time (at least dye composition (~2.4 years). The complex interaction of pigment nano-particles with LC molecules and the resulting effects on the LC electro-optical performances are still to be fully understood. We hope this work will not only demonstrate a new and practical approach for outdoor reflective colour displays but also provide a new material system for fundamental liquid crystal colloid research work.

  10. Wavy channel thin film transistor architecture for area efficient, high performance and low power displays

    KAUST Repository

    Hanna, Amir


    We demonstrate a new thin film transistor (TFT) architecture that allows expansion of the device width using continuous fin features - termed as wavy channel (WC) architecture. This architecture allows expansion of transistor width in a direction perpendicular to the substrate, thus not consuming extra chip area, achieving area efficiency. The devices have shown for a 13% increase in the device width resulting in a maximum 2.5× increase in \\'ON\\' current value of the WCTFT, when compared to planar devices consuming the same chip area, while using atomic layer deposition based zinc oxide (ZnO) as the channel material. The WCTFT devices also maintain similar \\'OFF\\' current value, ~100 pA, when compared to planar devices, thus not compromising on power consumption for performance which usually happens with larger width devices. This work offers an interesting opportunity to use WCTFTs as backplane circuitry for large-area high-resolution display applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Wall-shaped electrodes for reducing the operation voltage of polymer-stabilized blue phase liquid crystal displays

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Miyoung; Kim, Min Su; Kang, Byeong Gyun; Kim, Mi-Kyung; Yoon, Sukin; Lee, Seung Hee [Polymer BIN Fusion Research Center, Department of Polymer Nano-Science and Technology, Chonbuk National University, Chonju, Chonbuk 561-756 (Korea, Republic of); Ge Zhibing; Rao Linghui; Gauza, Sebastian; Wu, Shin-Tson, E-mail:, E-mail: swu@creol.ucf.ed [College of Optics and Photonics, University of Central Florida, Orlando, FL 32816 (United States)


    Polymer-stabilized blue phase liquid crystal displays based on the Kerr effect are emerging due to their submillisecond response time, wide view and simple fabrication process. However, the conventional in-plane switching device exhibits a relatively high operating voltage because the electric fields are restricted in the vicinity of the electrode surface. To overcome this technical barrier, we propose a partitioned wall-shaped electrode configuration so that the induced birefringence is uniform between electrodes throughout the entire cell gap. Consequently, the operating voltage is reduced by {approx} 2.8x with two transistors. The responsible physical mechanisms are explained.

  12. Development of High-Thrust and Double-Sided Linear Synchronous Motor Module For Liquid Crystal Display Equipment

    Institute of Scientific and Technical Information of China (English)

    Myung-jin; CHUNG; Sang-yeon; HWANG


    <正>Recently,there is an increasing requirement for controlling linear motion up to a few hundred of millimeter strokes in the area of the liquid crystal display(LCD) production equipment.The requirements of the motion system for LCD production equipment are high acceleration and high velocity with positioning accuracy.To satisfy these requirements,it has to be designed with the high-thrust force and low velocity ripple.In this work, high-thrust and double-sided linear synchronous motor (LSM)module is proposed and the developed high-thrust and double-sided LSM module is verified by performance test.

  13. Parallel aligned liquid crystal on silicon display based optical set-up for the generation of polarization spatial distributions (United States)

    Estévez, Irene; Lizana, Angel; Zheng, Xuejie; Peinado, Alba; Ramírez, Claudio; Martínez, Jose Luis; Márquez, Andrés.; Moreno, Ignacio; Campos, Juan


    Liquid Crystals on Silicon (LCOS) displays are a type of LCDs that work in reflection. Such devices, due to the double pass that the light beam performs through the LC cells, lead to larger phase modulation than transmissive LCDs with the same thickness. By taking advantage of this modulation capability exhibited by LCOS displays, we propose a new experimental set-up which is able to provide customized state of polarization spatial distributions just by means of a single LCOS display. To this aim, a double reflection on different halves of the display is properly performed. This fact is achieved by including a compact optical system that steers the light and performs a proper polarization plane rotation. The set-up has been experimentally implemented and some experimental concerns are discussed. The suitability of the system is provided by generating different experimental spatial distributions of polarization. In this regard, well-known polarization distributions, as axial, azimuthal or spiral linear polarization patterns are here provided. Based on the excellent results obtained, the suitability of the system to generate different spatially variant distributions of polarization is validated.

  14. Efficient method to optimize antibodies using avian leukosis virus display and eukaryotic cells. (United States)

    Yu, Changming; Pike, Gennett M; Rinkoski, Tommy A; Correia, Cristina; Kaufmann, Scott H; Federspiel, Mark J


    Antibody-based therapeutics have now had success in the clinic. The affinity and specificity of the antibody for the target ligand determines the specificity of therapeutic delivery and off-target side effects. The discovery and optimization of high-affinity antibodies to important therapeutic targets could be significantly improved by the availability of a robust, eukaryotic display technology comparable to phage display that would overcome the protein translation limitations of microorganisms. The use of eukaryotic cells would improve the diversity of the displayed antibodies that can be screened and optimized as well as more seamlessly transition into a large-scale mammalian expression system for clinical production. In this study, we demonstrate that the replication and polypeptide display characteristics of a eukaryotic retrovirus, avian leukosis virus (ALV), offers a robust, eukaryotic version of bacteriophage display. The binding affinity of a model single-chain Fv antibody was optimized by using ALV display, improving affinity >2,000-fold, from micromolar to picomolar levels. We believe ALV display provides an extension to antibody display on microorganisms and offers virus and cell display platforms in a eukaryotic expression system. ALV display should enable an improvement in the diversity of properly processed and functional antibody variants that can be screened and affinity-optimized to improve promising antibody candidates.

  15. High-Efficiency Nitride-Base Photonic Crystal Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    James Speck; Evelyn Hu; Claude Weisbuch; Yong-Seok Choi; Kelly McGroddy; Gregor Koblmuller; Elison Matioli; Elizabeth Rangel; Fabian Rol; Dobri Simeonov


    The research activities performed in the framework of this project represent a major breakthrough in the demonstration of Photonic Crystals (PhC) as a competitive technology for LEDs with high light extraction efficiency. The goals of the project were to explore the viable approaches to manufacturability of PhC LEDS through proven standard industrial processes, establish the limits of light extraction by various concepts of PhC LEDs, and determine the possible advantages of PhC LEDs over current and forthcoming LED extraction concepts. We have developed three very different geometries for PhC light extraction in LEDs. In addition, we have demonstrated reliable methods for their in-depth analysis allowing the extraction of important parameters such as light extraction efficiency, modal extraction length, directionality, internal and external quantum efficiency. The information gained allows better understanding of the physical processes and the effect of the design parameters on the light directionality and extraction efficiency. As a result, we produced LEDs with controllable emission directionality and a state of the art extraction efficiency that goes up to 94%. Those devices are based on embedded air-gap PhC - a novel technology concept developed in the framework of this project. They rely on a simple and planar fabrication process that is very interesting for industrial implementation due to its robustness and scalability. In fact, besides the additional patterning and regrowth steps, the process is identical as that for standard industrially used p-side-up LEDs. The final devices exhibit the same good electrical characteristics and high process yield as a series of test standard LEDs obtained in comparable conditions. Finally, the technology of embedded air-gap patterns (PhC) has significant potential in other related fields such as: increasing the optical mode interaction with the active region in semiconductor lasers; increasing the coupling of the incident

  16. Evaluation of improved efficiency with a diamond coating for a plasma display panel electrode (United States)

    Matsunaga, Yasushi; Kato, Tomokazu; Hatori, Tadatsugu; Hashiguchi, Seishiro


    Application of diamond to electrode coating of a plasma display panel (PDP) is evaluated, since we expect diamond to emit much secondary electron due to the Auger neutralization induced by Xe ions. In a conventional magnesium oxide-xenon (MgO/Xe) system, the most abundant Xe+ produced in the discharge does not effectively cause the secondary electron emission, because the condition of the Auger neutralization is not satisfied. In order to increase the efficiency of ultraviolet (UV) radiation, being especially important for engineering, we should avoid such inefficiency. Under suitable conditions in diamond/Xe system the Auger neutralization can occur. Further, if the electron affinity χ is negative, i.e., negative electron affinity (NEA), the condition of the Auger neutralization in diamond/Xe system is sufficiently satisfied. First, we calculate the coefficients of the secondary electron emission on diamond of clean surface or of hydrogenated surface where the dangling bonds are terminated, on the basis of the Hagstrum model. If the NEA with the electron affinity χ=-0.5 is realized, the high ion-induced secondary electron coefficients such as γXe=0.25 and γNe=0.32 are obtained. Next, we carry out a one-dimensional fluid simulation of the electric discharge in which the two secondary electron emission coefficients of Ne and Xe obtained theoretically are set. Results are presented with changing the sustaining voltage, the fraction of Xe, and the duration of the zero-voltage phase. For 10%Xe mixture, it is shown that the efficiency of UV radiation in the diamond coating increases two times higher than that in the MgO coating. An unnecessarily spontaneous breakdown during the zero-voltage phase, which is peculiar to high secondary electron emission materials, is observed. A mechanism of the breakdown is discussed and means to suppress it are proposed. Taking the zero-voltage phase short and increasing the fraction of Xe up to 50%, in comparison with MgO, a maximum


    Directory of Open Access Journals (Sweden)

    I. O. Zharinov


    Full Text Available Subject of Research.We consider the problem of evaluation of chromaticity coordinates shift for image displayed on liquid crystal panels with various properties on color reproduction. A mathematical model represents the color reproduction characteristics. The spread of the color characteristics of the screens has a statistical nature. Differences of color reproduction for screens are perceived by the observer in the form of different colors and shades that are displayed on the same type of commercially available screens. Color differences are characterized by numerical measure of the difference of colors and can be mathematically compensated. The solution of accounting problem of the statistical nature of the color characteristics spread for the screens has a particular relevance to aviation instrumentation. Method. Evaluation of chromaticity coordinates shift of the image is based on the application of the Grassmann laws of color mixing.Basic data for quantitative calculation of shift are the profiles of two different liquid crystal panels defined by matrixes of scales for components of primary colors (red, green, blue. The calculation is based on solving the system of equations and calculating the color difference in the XY-plane. In general, the calculation can be performed in other color spaces: UV, Lab. The statistical nature of the spread of the color characteristics for the screens is accounted for in the proposed mathematical model based on the interval setting of coordinate values of the color gamut triangle vertices on the set of commercially available samples. Main Results. Carried outresearches result in the mathematical expressions allowing to recalculate values of chromaticity coordinates of the image displayed on various samples of liquid crystal screens. It is shown that the spread of the color characteristics of the screens follows bivariate normal distribution law with the accuracy sufficient for practice. The results of

  18. Enhancement of a PALCoS display efficiency by reducing the influence of different non-desired phenomena (United States)

    Lizana, Ángel; Lobato, Laura; Márquez, Andrés; Moreno, Ignacio; Iemmi, Claudio; Campos, Juan


    This work presents a study of Parallel Aligned (PA) LCoS displays performance for their use to generate Diffractive Optical Elements (DOEs). First, we provide experimental evidences of two different physical phenomena, originated by the electrical addressing schemes used in LCoS displays, which degrade the efficiency of these devices. We refer to the time-fluctuations of the phase and the anamorphic phenomena. Besides, we propose different strategies to diminish the influence of these physical phenomena. First, a methodology based on the minimum Euclidian distance is proposed, leading to the minimization of the time-fluctuations of the phase influence. Second, by applying frequency dependent Look-Up Tables (LUTs) for the phase modulation, we demonstrate how the anamorphic response of the PALCoS display can be notably reduced. Finally, the application of these strategies leads to the best possible PALCoS display configuration in terms of efficiency. To show the significant improvement achieved on the DOEs efficiency, this optimized PALCoS display configuration is tested by experimentally generating diverse DOEs.

  19. Construction and Calibration of Optically Efficient LCD-based Multi-Layer Light Field Displays (United States)

    Hirsch, Matthew; Lanman, Douglas; Wetzstein, Gordon; Raskar, Ramesh


    Near-term commercial multi-view displays currently employ ray-based 3D or 4D light field techniques. Conventional approaches to ray-based display typically include lens arrays or heuristic barrier patterns combined with integral interlaced views on a display screen such as an LCD panel. Recent work has placed an emphasis on the co-design of optics and image formation algorithms to achieve increased frame rates, brighter images, and wider fields-of-view using optimization-in-the-loop and novel arrangements of commodity LCD panels. In this paper we examine the construction and calibration methods of computational, multi-layer LCD light field displays. We present several experimental configurations that are simple to build and can be tuned to sufficient precision to achieve a research quality light field display. We also present an analysis of moiré interference in these displays, and guidelines for diffuser placement and display alignment to reduce the effects of moiré. We describe a technique using the moiré magnifier to fine-tune the alignment of the LCD layers.

  20. Integrated light-guide plates that can control the illumination angle for liquid crystal display backlight system (United States)

    Feng, Di; Yang, Xingpeng; Jin, Guofan; Yan, Yingbai; Fan, Shoushan


    Liquid crystal displays (LCDs) with edge-lit backlight systems offer several advantages, such as low energy consuming, low weight, and high uniformity of intensity, over traditional cathode-ray tube displays, and make them ideal for many applications including monitors in notebook personal computers, screens for TV, and many portable information terminals, such as mobile phones, personal digital assistants, etc. To satisfy market requirements for mobile and personal display panels, it is more and more necessary to modify the backlight system and make it thinner, lighter, and brighter all at once. In this paper, we have proposed a new integrated LGP based on periodic and aperiodic microprism structures by using polymethyl methacrylate material, which can be designed to control the illumination angle, and to get high uniformity of intensity. So the backlight system will be simplified to use only light sources and one LGP without using other optical sheets, such as reflection sheet, diffusion sheet and prism sheets. By using optimizing program and ray tracing method, the designed LGPs can achieve a uniformity of intensity better than 86%, and get a peak illumination angle from +400 to -200, without requiring other optical sheets. We have designed a backlight system with only one LED light source and one LGP, and other LGP design examples with different sizes (1.8 inches and 14.1 inches) and different light source (LED or CCFL), are performed also.

  1. Image quality performance of liquid crystal display systems: influence of display resolution, magnification and window settings on contrast-detail detection. (United States)

    Bacher, Klaus; Smeets, Peter; De Hauwere, An; Voet, Tony; Duyck, Philippe; Verstraete, Koenraad; Thierens, Hubert


    The aim of this study was to investigate the combined effects of liquid crystal display (LCD) resolution, image magnification and window/level adjustment on the low-contrast performance in soft-copy image interpretation in digital radiography and digital mammography. In addition, the effect of a new LCD noise reduction mechanism on the low-contrast detectability was studied. Digital radiographs and mammograms of two dedicated contrast-detail phantoms (CDRAD 2.0 and CDMAM 3.4) were scored on five LCD devices with varying resolutions (1-3- and 5-megapixel) and one dedicated 5-megapixel cathode ray tube monitor. Two 5-megapixel LCDs were included. The first one was a standard 5-megapixel LCD and the second had a new (Per Pixel Uniformity) noise reduction mechanism. A multi-variate analysis of variance revealed a significant influence of LCD resolution, image magnification and window/level adjustment on the image quality performance assessed with both the CDRAD 2.0 and the CDMAM 3.4 phantoms. The interactive adjustment of brightness and contrast of digital images did not affect the reading time, whereas magnification to full resolution resulted in a significantly slower soft-copy interpretation. For digital radiography applications, a 3-megapixel LCD is comparable with a 5-megapixel CRT monitor in terms of low-contrast performance as well as in reading time. The use of a 2-megapixel LCD is only warranted when radiographs are analysed in full resolution and when using the interactive window/level adjustment. In digital mammography, a 5-megapixel monitor should be the first choice. In addition, the new PPU noise reduction system in the 5-megapixel LCD devices provides significantly better results for mammography reading as compared to a standard 5-magapixel LCD or CRT. If a 3-megapixel LCD is used in mammography setting, a very time-consuming magnification of the digital mammograms would be necessary.

  2. Image quality performance of liquid crystal display systems: Influence of display resolution, magnification and window settings on contrast-detail detection

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, Klaus [Department of Medical Physics and Radiation Protection, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium)]. E-mail:; Smeets, Peter [Department of Radiology, Ghent University Hospital, De Pintelaan 185, B-9000 Gent (Belgium); De Hauwere, An [Department of Medical Physics and Radiation Protection, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Voet, Tony [Department of Radiology, Ghent University Hospital, De Pintelaan 185, B-9000 Gent (Belgium); Duyck, Philippe [Department of Radiology, Ghent University Hospital, De Pintelaan 185, B-9000 Gent (Belgium); Verstraete, Koenraad [Department of Radiology, Ghent University Hospital, De Pintelaan 185, B-9000 Gent (Belgium); Thierens, Hubert [Department of Medical Physics and Radiation Protection, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium)


    The aim of this study was to investigate the combined effects of liquid crystal display (LCD) resolution, image magnification and window/level adjustment on the low-contrast performance in soft-copy image interpretation in digital radiography and digital mammography. In addition, the effect of a new LCD noise reduction mechanism on the low-contrast detectability was studied. Digital radiographs and mammograms of two dedicated contrast-detail phantoms (CDRAD 2.0 and CDMAM 3.4) were scored on five LCD devices with varying resolutions (1-3- and 5-megapixel) and one dedicated 5-megapixel cathode ray tube monitor. Two 5-megapixel LCDs were included. The first one was a standard 5-megapixel LCD and the second had a new (Per Pixel Uniformity) noise reduction mechanism. A multi-variate analysis of variance revealed a significant influence of LCD resolution, image magnification and window/level adjustment on the image quality performance assessed with both the CDRAD 2.0 and the CDMAM 3.4 phantoms. The interactive adjustment of brightness and contrast of digital images did not affect the reading time, whereas magnification to full resolution resulted in a significantly slower soft-copy interpretation. For digital radiography applications, a 3-megapixel LCD is comparable with a 5-megapixel CRT monitor in terms of low-contrast performance as well as in reading time. The use of a 2-megapixel LCD is only warranted when radiographs are analysed in full resolution and when using the interactive window/level adjustment. In digital mammography, a 5-megapixel monitor should be the first choice. In addition, the new PPU noise reduction system in the 5-megapixel LCD devices provides significantly better results for mammography reading as compared to a standard 5-magapixel LCD or CRT. If a 3-megapixel LCD is used in mammography setting, a very time-consuming magnification of the digital mammograms would be necessary.

  3. Assistance to bone milling: a tool mounted visual display improves the efficiency of robotic guidance. (United States)

    Francoise, Vincent; Sahbani, Anis; Roby-Brami, Agnes; Morel, Guillaume


    In this paper, a new kind of assistance for bone milling is disclosed. It combines a robotic comanipulator applying forces to guide the milling tool tip with a visual display mounted on the hand-held tool. This visual display is a LED bargraph providing to the user a geometric information that is mostly redundant with the forces exerted by the robot, thus constituting a multi-modal feedback. Although very basic and rather inexpensive, the additional visual display is experimentally shown to significantly improve the precision of the gesture.

  4. Direct current electric field assembly of colloidal crystals displaying reversible structural color. (United States)

    Shah, Aayush A; Ganesan, Mahesh; Jocz, Jennifer; Solomon, Michael J


    We report the application of low-voltage direct current (dc) electric fields to self-assemble close-packed colloidal crystals in nonaqueous solvents from colloidal spheres that vary in size from as large as 1.2 μm to as small as 0.1 μm. The assemblies are created rapidly (∼2 min) from an initially low volume fraction colloidal particle suspension using a simple capacitor-like electric field device that applies a steady dc electric voltage. Confocal microscopy is used to observe the ordering that is produced by the assembly method. This spatial evidence for ordering is consistent with the 6-fold diffraction patterns identified by light scattering. Red, green, and blue structural color is observed for the ordered assemblies of colloids with diameters of 0.50, 0.40, and 0.29 μm, respectively, consistent with spectroscopic measurements of reflectance. The diffraction and spectrophotometry results were found to be consistent with the theoretical Bragg's scattering expected for closed-packed crystals. By switching the dc electric field from on to off, we demonstrate reversibility of the structural color response on times scales ∼60 s. The dc electric field assembly method therefore represents a simple method to produce reversible structural color in colloidal soft matter.

  5. Brightness-Luminance Ratio of a Liquid Crystal Display in a Transmission Type (United States)

    Shimomura, Teruo


    A psychological experiment was executed binocularly for a bipartite or a separated field. The viewing subtence was 2° in both fields and the spatial separation in a separated field was 1°. Seven observers adjusted the luminance of a white comparison stimulus to appear equally as bright as a test stimulus of a liquid crystal cell. Red-, green-, blue-color under the tunable birefringence mode were shown as a test stimulus. The ratios of the mean observer in a bipartite field were 1.35± 0.23 for red, 1.20± 0.13 for green, 1.06± 0.13 for blue, and lower than those in a separated field.

  6. Generalized nematohydrodynamic boundary conditions with application to bistable twisted nematic liquid-crystal displays

    KAUST Repository

    Fang, Angbo


    Parallel to the highly successful Ericksen-Leslie hydrodynamic theory for the bulk behavior of nematic liquid crystals (NLCs), we derive a set of coupled hydrodynamic boundary conditions to describe the NLC dynamics near NLC-solid interfaces. In our boundary conditions, translational flux (flow slippage) and rotational flux (surface director relaxation) are coupled according to the Onsager variational principle of least energy dissipation. The application of our boundary conditions to the truly bistable π -twist NLC cell reveals a complete picture of the dynamic switching processes. It is found that the thus far overlooked translation-rotation dissipative coupling at solid surfaces can accelerate surface director relaxation and enhance the flow rate. This can be utilized to improve the performance of electro-optical nematic devices by lowering the required switching voltages and reducing the switching times. © 2008 The American Physical Society.

  7. Highly efficient fluorescence sensing with hollow core photonic crystal fibers


    Smolka, Stephan; Barth, Michael; Benson, Oliver


    We investigate hollow core photonic crystal fibers for ultra-sensitive fluorescence detection by selectively infiltrating the central hole with fluorophores. Dye concentrations down to 10(-9) M can be detected using only nanoliter sample volumes.

  8. Highly efficient fluorescence sensing with hollow core photonic crystal fibers

    DEFF Research Database (Denmark)

    Smolka, Stephan; Barth, Michael; Benson, Oliver


    We investigate hollow core photonic crystal fibers for ultra-sensitive fluorescence detection by selectively infiltrating the central hole with fluorophores. Dye concentrations down to 10(-9) M can be detected using only nanoliter sample volumes.......We investigate hollow core photonic crystal fibers for ultra-sensitive fluorescence detection by selectively infiltrating the central hole with fluorophores. Dye concentrations down to 10(-9) M can be detected using only nanoliter sample volumes....

  9. 11% efficient single-crystal solar cells and 10% efficient polycrystalline cells made from refined metallurgical silicon (United States)

    Hanoka, J. I.; Strock, H. B.; Kotval, P. S.


    The performances of single-crystal and polycrystalline solar cells fabricated from a refined form of low-cost metallurgical silicon are presented. Czochralski-pulled single crystal and cast polycrystalline silicon solar cells with an n on p structure were made from metallurgical silicon processed by Al dissolution followed by Al removal through slagging and directional solidification to obtain material purities in the fractional ppm by weight range. For the single-crystal cells, measurements reveal AM1 efficiencies up to 11.1%, open circuit voltages up to 596 mV and fill factors up to 81%. The cast polycrystalline substrates have yielded cells with efficiencies up to 10.1%, fill factors of 79% and open circuit voltages of 585 mV. The low short circuit current densities are attributed to impurities in the base region in the single-crystal cell, and to grain boundary segregation of impurities and grain boundary recombination in the polycrystalline cells.

  10. Crystal Structures of Human SIRT[subscript 3] Displaying Substrate-induced Conformational Changes

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Lei; Wei, Wentao; Jiang, Yaobin; Peng, Hao; Cai, Jianhua; Mao, Chen; Dai, Han; Choy, Wendy; Bemis, Jean E.; Jirousek, Michael R.; Milne, Jill C.; Westphal, Christoph H.; Perni, Robert B.; (Viva Biotech); (Medicilon); (GSK)


    SIRT3 is a major mitochondrial NAD{sup +}-dependent protein deacetylase playing important roles in regulating mitochondrial metabolism and energy production and has been linked to the beneficial effects of exercise and caloric restriction. SIRT3 is emerging as a potential therapeutic target to treat metabolic and neurological diseases. We report the first sets of crystal structures of human SIRT3, an apo-structure with no substrate, a structure with a peptide containing acetyl lysine of its natural substrate acetyl-CoA synthetase 2, a reaction intermediate structure trapped by a thioacetyl peptide, and a structure with the dethioacetylated peptide bound. These structures provide insights into the conformational changes induced by the two substrates required for the reaction, the acetylated substrate peptide and NAD+. In addition, the binding study by isothermal titration calorimetry suggests that the acetylated peptide is the first substrate to bind to SIRT3, before NAD{sup +}. These structures and biophysical studies provide key insight into the structural and functional relationship of the SIRT3 deacetylation activity.

  11. Zero-valent iron pretreatment for detoxifying iodine in liquid crystal display (LCD) manufacturing wastewater. (United States)

    Lee, J W; Cha, D K; Oh, Y K; Ko, K B; Song, J S


    This study investigated reductive transformation of iodine by zero-valent iron (ZVI), and the subsequent detoxification of iodine-laden wastewater. ZVI completely reduced aqueous iodine to non-toxic iodide. Respirometric bioassay illustrated that the presence of iodine increase the lag phase before the onset of oxygen consumption. The length of lag phase was proportional to increasing iodine dosage. The reduction products of iodine by ZVI did not exhibit any inhibitory effect on the biodegradation. The cumulative biological oxidation associated with iodine toxicity was closely fitted to Gompertz model. When iodine-laden wastewater was continuously fed to a bench-scale activated sludge unit, chemical oxygen demand (COD) removal efficiencies decreased from above 90% to below 80% along with a marked decrease in biomass concentration. On the other hand, the COD removal efficiency and biomass concentration remained constant in the integrated ZVI-activated sludge system. Respirometric bioassay with real iodine-laden LCD manufacturing wastewater demonstrated that ZVI was effective for detoxifying iodine and consequently enhancing biodegradability of wastewater. This result suggested that ZVI pretreatment may be a feasible option for the removal of iodine in LCD processing wastewater, instead of more costly processes such as adsorption and chemical oxidation, which are commonly in the iodine-laden LCD wastewater treatment facility.

  12. An improved single-chain Fab platform for efficient display and recombinant expression. (United States)

    Koerber, James T; Hornsby, Michael J; Wells, James A


    Antibody phage display libraries combined with high-throughput selections have recently demonstrated tremendous promise to create the next generation of renewable, recombinant antibodies to study proteins and their many post-translational modification states; however, many challenges still remain, such as optimized antibody scaffolds. Recently, a single-chain fragment antigen binding (Fab) (scFab) format, in which the carboxy-terminus of the light chain is linked to the amino-terminus of the heavy chain, was described to potentially combine the high display levels of a single-chain fragment variable with the high stability of purified Fabs. However, this format required removal of the interchain disulfide bond to achieve modest display levels and subsequent bacterial expression resulted in high levels of aggregated scFab, hindering further use of scFabs. Here, we developed an improved scFab format that retains the interchain disulfide bond by increasing the linker length between the light and heavy chains to improve display and bacterial expression levels to 1-3 mg/L. Furthermore, rerouting of the scFab to the co-translational signal recognition particle pathway combined with reengineering of the signal peptide sequence results in display levels 24-fold above the original scFab format and 3-fold above parent Fab levels. This optimized scFab scaffold can be easily reformatted in a single step for expression in a bacterial or mammalian host to produce stable (Tm of 81 °C), predominantly monomeric (>90%) antibodies at a high yield. Ultimately, this new scFab format will advance high-throughput antibody generation platforms to discover the next generation of research and therapeutic antibodies.

  13. Efficiency of frequency conversion of high power laser and KDP crystal clamping method (United States)

    Yan, Han; Du, Weifeng; Pei, Guoqing; Qin, Tinghai; Ye, Lang; Xu, Xu


    In the high power solid laser driver, the frequency conversion unit is of strict requirement to meet the drive condition of ICF. The performance of large caliber KDP crystal, which is the core of frequency conversion of laser, is a vital aspect affecting the overall technical index of the laser driver. In order to get a higher efficiency of frequency conversion, KDP crystal must keep a better surface condition, which asks for high-quality assemblage and adjustment. The current method used in engineering has insufficient knowledge and recognition on surface deformation control of the crystal. Meanwhile, the method itself is of low efficiency on clamping, and lacks of protection for the crystal. Thus, in this article an investigation of crystal clamping method with lower force was performed, factors affecting the surface of crystal were explored, through both imitation and experiment. The clamping method was redesigned and the frequency conversion efficiency was tested. Meanwhile, with the new method, clamping efficiency increases, the optical performance of crystals improves, and the crystals get better protection.

  14. Dispersion engineered cob-web photonic crystal fibers for efficient supercontinuum generation


    Sørensen, Niels Thorkild; Nikolov, N. I.; Bang, Ole; Bjarklev, Anders Overgaard; Hougaard, Kristian G.; Hansen, Kim Per


    Highly nonlinear cob-web photonic crystal fibers are engineered to have dispersion profiles for efficient direct degenerate four-wave mixing and optimized supercontinuum generation with low-power picosecond pulses. This process is robust to fiber irregularities.

  15. High efficient OLED displays prepared with the air-gapped bridges on quantum dot patterns for optical recycling (United States)

    Kim, Hyo-Jun; Shin, Min-Ho; Kim, Joo-Suc; Kim, Se-Eun; Kim, Young-Joo


    An optically efficient structure was proposed and fabricated to realize high brightness organic light emitting diode (OLED) displays based on a white OLED prepared with the air-gapped bridges on the quantum dot (QD) patterns. Compared with a conventional white OLED display, in our experiments, the optical intensity of the proposed OLED display shows the enhancement of 58.2% in the red color and 16.8% in the green color after applying the air-gapped bridge structure on QD patterns of 20 wt% concentration. This enhancement comes from the two facts that the QD patterns downconvert unnecessary blue or blue/green light to the required green or red light and the air-gapped bridges increase the color conversion efficiency of QDs by optical recycling using total internal reflection (TIR) at the interface. In addition, the color gamut of the proposed OLED display increases from 65.5 to 75.9% (NTSC x, y ratio) due to the narrow emission spectra of QDs.

  16. Dispersion engineered cob-web photonic crystal fibers for efficient supercontinuum generation

    DEFF Research Database (Denmark)

    Sørensen, Niels Thorkild; Nikolov, N.I.; Bang, Ole;


    Highly nonlinear cob-web photonic crystal fibers are engineered to have dispersion profiles for efficient direct degenerate four-wave mixing and optimized supercontinuum generation with low-power picosecond pulses. This process is robust to fiber irregularities.......Highly nonlinear cob-web photonic crystal fibers are engineered to have dispersion profiles for efficient direct degenerate four-wave mixing and optimized supercontinuum generation with low-power picosecond pulses. This process is robust to fiber irregularities....

  17. Topology design and fabrication of an efficient double 90° photonic crystal waveguide bend

    DEFF Research Database (Denmark)

    Jensen, Jakob Søndergaard; Sigmund, Ole; Frandsen, Lars Hagedorn


    We have designed and fabricated a novel 90 bend in a photonic crystal waveguide. The design was obtained using topology optimization and the fabricated waveguide displays a bend loss for transverse-electric-polarized light of less than 1 dB per bend in a 200-nm wavelength range....

  18. Possibility of high efficient beam extraction from the CERN SPS with a bent crystal. Simulation results (United States)

    Scandale, W.; Kovalenko, A. D.; Taratin, A. M.


    The extraction of the SPS beam of 270 GeV/c protons assisted by a bent crystal was studied by simulation. Two methods for delivering the SPS beam onto a crystal were considered: transverse diffusion and orbit bump of the beam. It was shown that the main condition for high efficient beam extraction with a bent crystal, which is a small divergence of the incident beam, can be fulfilled. Extraction efficiency up to 99% can be reached for both methods of the beam delivering. The irradiation of the electrostatic septum wires during the beam extraction can be considerably reduced.

  19. Optimized photonic crystal fibers supporting efficient capillary electrophoresis (United States)

    Calcerrada, M.; García-Ruiz, C.; Roy, P.; Gonzalez-Herraez, M.


    In this paper we present preliminary results on the use of Photonic Crystal Fibers (PCFs) in a conventional capillary electrophoresis system to separate and detect fluorescent species. PCFs show interesting advantages over conventional capillaries for this application, including larger surface-to-volume ratio and potential for higher resolution with comparable sensitivity. Our results illustrate some of these advantages, and we point out the need for stringent tolerances in the fabrication of specific PCFs for this application.

  20. Experimentally determining the relative efficiency of spherically bent germanium and quartz crystals (United States)

    Brown, G. V.; Beiersdorfer, P.; Hell, N.; Magee, E.


    We have used the EBIT-I electron beam ion trap at the Lawrence Livermore National Laboratory and a duplicate Orion High Resolution X-ray Spectrometer (OHREX) to measure the relative efficiency of a spherically bent quartz (10 1 ¯ 1) crystal (2d = 6.687 Å) and a spherically bent germanium (111) crystal (2d = 6.532 Å). L-shell X-ray photons from highly charged molybdenum ions generated in EBIT-I were simultaneously focussed and Bragg reflected by each crystal, both housed in a single spectrometer, onto a single CCD X-ray detector. The flux from each crystal was then directly compared. Our results show that the germanium crystal has a reflection efficiency significantly better than the quartz crystal, however, the energy resolution is significantly worse. Moreover, we find that the spatial focussing properties of the germanium crystal are worse than those of the quartz crystal. Details of the experiment are presented, and we discuss the advantages of using either crystal on a streak-camera equipped OHREX spectrometer.

  1. Improved power conversion efficiency of dye-sensitized solar cells using side chain liquid crystal polymer embedded in polymer electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Woosum [Department of Chemistry Education, and Department of Frontier Materials Chemistry, and Institute for Plastic Information and Energy Materials, Pusan National University, Busan 609-735 (Korea, Republic of); Lee, Jae Wook, E-mail: [Department of Chemistry, Dong-A University, Busan 604-714 (Korea, Republic of); Gal, Yeong-Soon [Polymer Chemistry Lab, College of General Education, Kyungil University, Hayang 712-701 (Korea, Republic of); Kim, Mi-Ra, E-mail: [Department of Polymer Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Jin, Sung Ho, E-mail: [Department of Chemistry Education, and Department of Frontier Materials Chemistry, and Institute for Plastic Information and Energy Materials, Pusan National University, Busan 609-735 (Korea, Republic of)


    Side chain liquid crystal polymer (SCLCP) embedded in poly(vinylidenefluoride-co-hexafluoropropylene) (PVdF-co-HFP)-based polymer electrolytes (PVdF-co-HFP:side chain liquid crystal polymer (SCLCP)) was prepared for dye-sensitized solar cell (DSSC) application. The polymer electrolytes contained tetrabutylammonium iodide (TBAI), iodine (I{sub 2}), and 8 wt% PVdF-co-HFP in acetonitrile. DSSCs comprised of PVdF-co-HFP:SCLCP-based polymer electrolytes displayed enhanced redox couple reduction and reduced charge recombination in comparison to those of the conventional PVdF-co-HFP-based polymer electrolyte. The significantly increased short-circuit current density (J{sub sc}, 10.75 mA cm{sup −2}) of the DSSCs with PVdF-co-HFP:SCLCP-based polymer electrolytes afforded a high power conversion efficiency (PCE) of 5.32% and a fill factor (FF) of 0.64 under standard light intensity of 100 mW cm{sup −2} irradiation of AM 1.5 sunlight. - Highlights: • We developed the liquid crystal polymer embedded on polymer electrolyte for DSSCs. • We fabricated the highly efficient DSSCs using polymer electrolyte. • The best PCE achieved for P1 is 5.32% using polymer electrolyte.

  2. Efficient production of D-tagatose using a food-grade surface display system. (United States)

    Liu, Yi; Li, Sha; Xu, Hong; Wu, Lingtian; Xu, Zheng; Liu, Jing; Feng, Xiaohai


    D-tagatose, a functional sweetener, is commonly transformed from D-galactose by L-arabinose isomerase (L-AI). In this study, a novel type of biocatalyst, L-AI from Lactobacillus fermentum CGMCC2921 displayed on the spore surface of Bacillus subtilis 168, was developed for producing D-tagatose. The anchored L-AI, exhibiting the relatively high bioactivity, suggested that the surface display system using CotX as the anchoring protein was successfully constructed. The stability of the anchored L-AI was significantly improved. Specifically, the consolidation of thermal stability representing 87% of relative activity was retained even at 80 °C for 30 min, which remarkably favored the production of D-tagatose. Under the optimal conditions, the robust spores can convert 75% D-galactose (100 g/L) into D-tagatose after 24 h, and the conversion rate remained at 56% at the third cycle. Therefore, this biocatalysis system, which could express the target enzyme on the food-grade vector, was an alternative method for the value-added production of D-tagatose.

  3. Electrophoresis Gel Quantification with a Flatbed Scanner and Versatile Lighting from a Screen Scavenged from a Liquid Crystal Display (LCD) Monitor (United States)

    Yeung, Brendan; Ng, Tuck Wah; Tan, Han Yen; Liew, Oi Wah


    The use of different types of stains in the quantification of proteins separated on gels using electrophoresis offers the capability of deriving good outcomes in terms of linear dynamic range, sensitivity, and compatibility with specific proteins. An inexpensive, simple, and versatile lighting system based on liquid crystal display backlighting is…

  4. Electrophoresis Gel Quantification with a Flatbed Scanner and Versatile Lighting from a Screen Scavenged from a Liquid Crystal Display (LCD) Monitor (United States)

    Yeung, Brendan; Ng, Tuck Wah; Tan, Han Yen; Liew, Oi Wah


    The use of different types of stains in the quantification of proteins separated on gels using electrophoresis offers the capability of deriving good outcomes in terms of linear dynamic range, sensitivity, and compatibility with specific proteins. An inexpensive, simple, and versatile lighting system based on liquid crystal display backlighting is…

  5. Exposure to volatile organic compounds and kidney dysfunction in thin film transistor liquid crystal display (TFT-LCD) workers. (United States)

    Chang, Ta-Yuan; Huang, Kuei-Hung; Liu, Chiu-Shong; Shie, Ruei-Hao; Chao, Keh-Ping; Hsu, Wen-Hsin; Bao, Bo-Ying


    Many volatile organic compounds (VOCs) are emitted during the manufacturing of thin film transistor liquid crystal displays (TFT-LCDs), exposure to some of which has been reported to be associated with kidney dysfunction, but whether such an effect exists in TFT-LCD industry workers is unknown. This cross-sectional study aimed to investigate the association between exposure to VOCs and kidney dysfunction among TFT-LCD workers. The results showed that ethanol (1811.0+/-1740.4 ppb), acetone (669.0+/-561.0 ppb), isopropyl alcohol (187.0+/-205.3 ppb) and propylene glycol monomethyl ether acetate (PGMEA) (102.9+/-102.0 ppb) were the four dominant VOCs present in the workplace. The 63 array workers studied had a risk of kidney dysfunction 3.21-fold and 3.84-fold that of 61 cell workers and 18 module workers, respectively. Workers cumulatively exposed to a total level of isopropyl alcohol, PGMEA and propylene glycol monomethyl ether> or =324 ppb-year had a significantly higher risk of kidney dysfunction (adjusted OR=3.41, 95% CI=1.14-10.17) compared with those exposed to LCD industry, and cumulative exposure to specific VOCs might be associated with kidney dysfunction.

  6. Use of thin film transistor liquid crystal display (TFT-LCD) waste glass in the production of ceramic tiles. (United States)

    Lin, Kae-Long


    In this study, we employ the following operating conditions: varied pressure (25 kgf/cm(2)), sintering temperature (900-1200 degrees C), sintering time (6h), percentage of thin film transistor liquid crystal display (TFT-LCD) waste glass by weight (0-50%) and temperature rising at a rate of 5 degrees C/min, to fabricate clay tiles. The sintering characteristics of the clay blended with TFT-LCD waste glass tiles are examined to evaluate the feasibility of the reuse of TFT-LCD waste glass. TFT-LCD waste glass contains large amounts of glass. The TCLP leaching concentrations all met the ROC EPAs current regulatory thresholds. The addition of TFT-LCD waste glass to the mixture, increased the apparent weight loss. The incorporation of 50% TFT-LCD waste glass resulted in a significant increase in the porosity ratio of the specimens compared to the porosity ratio of the ceramic tile containing TFT-LCD waste glass. The main constituent in both the clay tile and the clay with TFT-LCD waste glass samples is quartz. Increasing the temperature resulted in an increase in the flexural strength and resistance to abrasion in the tiles. The porosity ratio decreases as shrinkage increases. The relation between the porosity ratio and the hardness of the tiles used in the study is also shown.

  7. Dendronized Polyimides Bearing Long-Chain Alkyl Groups and Their Application for Vertically Aligned Nematic Liquid Crystal Displays

    Directory of Open Access Journals (Sweden)

    Yusuke Tsuda


    Full Text Available Polyimides having dendritic side chains were investigated. The terphenylene diamine monomer having a first-generation monodendron, 3,4,5-tris(n-dodecyloxy-benzoate and the monomer having a second-generation monodendron, 3,4,5-tris[-3’,4’,5’-tri(n-dodecyloxybenzyloxy]benzoate were successfully synthesized and the corresponding soluble dendritic polyimides were obtained by polycondensation with conventional tetracarboxylic dianhydride monomers such as benzophenone tertracarboxylic dianhydride (BTDA. The two-step polymerizations in NMP that is a general method for the synthesis of soluble polyimides is difficult; however, the expected dendritic polyimides can be obtained in aromatic polar solvents such as m-cresol and pyridine. The solubility of these dendoronized polyimides is characteristic; soluble in common organic solvents such as dichloromethane, chloroform, toluene and THF. These dendronized polyimides exhibited high glass transition temperatures and good thermal stability in both air and under nitrogen. Their application as alignment layers for LCDs was investigated, and it was found that these polyimides having dendritic side chains were applicable for the vertically aligned nematic liquid crystal displays (VAN-LCDs.

  8. Fluorescence depolarization and contact angle investigation of dynamic and static interfacial tension of liquid crystal display materials. (United States)

    Quintella, Cristina M; Lima, Angelo M V; Gonçalves, Cristiane C; Watanabe, Yuji N; Mammana, Alaide P; Schreiner, Marcos A; Pepe, Iuri; Pizzo, Angela A


    Interfacial interactions control two processes empirically known to be critical for molecular anchoring in twisted nematic liquid crystal displays technology (TN-LCDs): surface treatment and filling procedure. Static and dynamical interfacial tensions (Gamma(SL)) between liquids and several substrates with similar roughness were observed respectively by contact angle (theta(c)) of sessile drops and by fluorescence depolarization of thin liquid films flowing at high velocity. Gamma(SL) decreased when glass was coated with tin dioxide and increased with polyvinyl alcohol (PVA) deposition. Drops were circular for all substrates except rubbed PVA, where they flowed spontaneously along the rubbing direction, reaching an oblong form that had theta(c) parallel and perpendicular to the rubbing direction respectively greater and smaller than theta(c) for non-rubbed PVA. This is attributed to polar group alignment generating an asymmetric Gamma(SL) distribution with nanometric preferential direction, inducing a capillary-like flow. Polarization and anisotropy maps for high-velocity flow parallel to the PVA rubbing direction showed an increase in the net alignment of molecular domains and a widening of the region where it occurred. This is attributed to preferential anchoring in the downstream direction, instead of in several directions, as for non-rubbed PVA. This explains why filling direction is crucial for TN-LCDs homogeneous behavior.

  9. Efficient modeling of photonic crystals with local Hermite polynomials (United States)

    Boucher, C. R.; Li, Zehao; Albrecht, J. D.; Ram-Mohan, L. R.


    Developing compact algorithms for accurate electrodynamic calculations with minimal computational cost is an active area of research given the increasing complexity in the design of electromagnetic composite structures such as photonic crystals, metamaterials, optical interconnects, and on-chip routing. We show that electric and magnetic (EM) fields can be calculated using scalar Hermite interpolation polynomials as the numerical basis functions without having to invoke edge-based vector finite elements to suppress spurious solutions or to satisfy boundary conditions. This approach offers several fundamental advantages as evidenced through band structure solutions for periodic systems and through waveguide analysis. Compared with reciprocal space (plane wave expansion) methods for periodic systems, advantages are shown in computational costs, the ability to capture spatial complexity in the dielectric distributions, the demonstration of numerical convergence with scaling, and variational eigenfunctions free of numerical artifacts that arise from mixed-order real space basis sets or the inherent aberrations from transforming reciprocal space solutions of finite expansions. The photonic band structure of a simple crystal is used as a benchmark comparison and the ability to capture the effects of spatially complex dielectric distributions is treated using a complex pattern with highly irregular features that would stress spatial transform limits. This general method is applicable to a broad class of physical systems, e.g., to semiconducting lasers which require simultaneous modeling of transitions in quantum wells or dots together with EM cavity calculations, to modeling plasmonic structures in the presence of EM field emissions, and to on-chip propagation within monolithic integrated circuits.

  10. Biological treatment of thin-film transistor liquid crystal display (TFT-LCD) wastewater using aerobic and anoxic/oxic sequencing batch reactors. (United States)

    Lei, Chin-Nan; Whang, Liang-Ming; Chen, Po-Chun


    The amount of pollutants produced during manufacturing processes of thin-film transistor liquid crystal display (TFT-LCD) substantially increases due to an increasing production of the opto-electronic industry in Taiwan. This study presents the treatment performance of one aerobic and one anoxic/oxic (A/O) sequencing batch reactors (SBRs) treating synthetic TFT-LCD wastewater containing dimethyl sulfoxide (DMSO), monoethanolamine (MEA), and tetra-methyl ammonium hydroxide (TMAH). The long-term monitoring results for the aerobic and A/O SBRs demonstrate that stable biodegradation of DMSO, MEA, and TMAH can be achieved without any considerably adverse impacts. The ammonium released during MEA and TMAH degradation can also be completely oxidized to nitrate through nitrification in both SBRs. Batch studies on biodegradation rates for DMSO, MEA, and TMAH under anaerobic, anoxic, and aerobic conditions indicate that effective MEA degradation can be easily achieved under all three conditions examined, while efficient DMSO and TMAH degradation can be attained only under anaerobic and aerobic conditions, respectively. The potential odor problem caused by the formation of malodorous dimethyl sulfide from DMSO degradation under anaerobic conditions, however, requires insightful consideration in treating DMSO-containing wastewater.

  11. Highly efficient single-pass sum frequency generation by cascaded nonlinear crystals

    DEFF Research Database (Denmark)

    Hansen, Anders Kragh; Andersen, Peter E.; Jensen, Ole Bjarlin;


    , despite differences in the phase relations of the involved fields. An unprecedented 5.5 W of continuous-wave diffraction-limited green light is generated from the single-pass sum frequency mixing of two diode lasers in two periodically poled nonlinear crystals (conversion efficiency 50%). The technique......The cascading of nonlinear crystals has been established as a simple method to greatly increase the conversion efficiency of single-pass second-harmonic generation compared to a single-crystal scheme. Here, we show for the first time that the technique can be extended to sum frequency generation...... is generally applicable and can be applied to any combination of fundamental wavelengths and nonlinear crystals....

  12. Measurement of neutron detection efficiencies in NaI using the Crystal Ball detector

    Energy Technology Data Exchange (ETDEWEB)

    Stanislaus, T.D.S.; Koetke, D.D. E-mail:; Allgower, C.; Bekrenev, V.; Benslama, K.; Berger, E.; Briscoe, W.J.; Clajus, M.; Comfort, J.R.; Craig, K.; Gibson, A.; Grosnick, D.; Huber, G.M.; Isenhower, D.; Kasprzyk, T.; Knecht, N.; Koulbardis, A.; Kozlenko, N.; Kruglov, S.; Kycia, T.; Lolos, G.J.; Lopatin, I.; Manley, D.M.; Manweiler, R.; Marusic, A.; McDonald, S.; Nefkens, B.M.K.; Olmsted, J.; Papandreou, Z.; Peaslee, D.; Peterson, R.J.; Phaisangittisakul, N.; Pulver, M.; Ramirez, A.F.; Sadler, M.; Shafi, A.; Slaus, I.; Spinka, H.; Starostin, A.; Staudenmaier, H.M.; Supek, I.; Thoms, J.; Tippens, W.B


    We report on a measurement of the neutron detection efficiency in NaI crystals in the Crystal Ball (CB) detector obtained from a study of {pi}{sup -}p{yields}{pi} degree sign n reactions at the Brookhaven National Laboratory AGS. A companion GEANT-based Monte Carlo study has been done to simulate these reactions in the CB, and a comparison with the data is provided.

  13. A new measurement of the neutron detection efficiency for the NaI Crystal Ball detector

    CERN Document Server

    Martemianov, M; Demissie, B T; Marinides, Z; Akondi, C S; Annand, J R M; Arends, H J; Beck, R; Borisov, N; Braghieri, A; Briscoe, W J; Cherepnya, S; Collicott, C; Costanza, S; Downie, E J; Dieterle, M; Bondy, M I Ferretti; Filkov, L V; Garni, S; Glazier, D I; Glowa, D; Gradl, W; Gurevich, G; Hornidge, D; Huber, G M; Kaeser, A; Kashevarov, V L; Keshelashvili, I; Kondratiev, R; Korolija, M; Krusche, B; Lazarev, A; Linturi, J M; Lisin, V; Livingston, K; MacGregor, I J D; Manley, D M; Martel, P P; Middleton, D G; Miskimen, R; Mushkarenkov, A; Neganov, A; Neiser, A; Oberle, M; Ostrick, M; Ott, P; Otte, P B; Oussena, B; Pedroni, P; Polonski, A; Prakhov, S; Ron, G; Rostomyan, T; Sarty, A; Schott, D M; Schumann, S; Sokhoyan, V; Steffen, O; Strakovsky, I I; Strub, Th; Supek, I; Thiel, M; Thomas, A; Unverzagt, M; Usov, Yu A; Wagner, S; Watts, D P; Wettig, J; Werthmuller, D; Witthauer, L; Wolfes, M


    We report on a measurement of the neutron detection efficiency in NaI crystals in the Crystal Ball detector obtained from a study of single p0 photoproduction on deuterium using the tagged photon beam at the Mainz Microtron. The results were obtained up to a neutron energy of 400 MeV. They are compared to previous measurements made more than 15 years ago at the pion beam at the BNL AGS.

  14. Measurement of neutron detection efficiencies in NaI using the Crystal Ball detector (United States)

    Stanislaus, T. D. S.; Koetke, D. D.; Allgower, C.; Bekrenev, V.; Benslama, K.; Berger, E.; Briscoe, W. J.; Clajus, M.; Comfort, J. R.; Craig, K.; Gibson, A.; Grosnick, D.; Huber, G. M.; Isenhower, D.; Kasprzyk, T.; Knecht, N.; Koulbardis, A.; Kozlenko, N.; Kruglov, S.; Kycia, T.; Lolos, G. J.; Lopatin, I.; Manley, D. M.; Manweiler, R.; Marusic, A.; McDonald, S.; Nefkens, B. M. K.; Olmsted, J.; Papandreou, Z.; Peaslee, D.; Peterson, R. J.; Phaisangittisakul, N.; Pulver, M.; Ramirez, A. F.; Sadler, M.; Shafi, A.; Slaus, I.; Spinka, H.; Starostin, A.; Staudenmaier, H. M.; Supek, I.; Thoms, J.; Tippens, W. B.


    We report on a measurement of the neutron detection efficiency in NaI crystals in the Crystal Ball (CB) detector obtained from a study of π-p→ π°n reactions at the Brookhaven National Laboratory AGS. A companion GEANT-based Monte Carlo study has been done to simulate these reactions in the CB, and a comparison with the data is provided.

  15. Epitaxial Ultrathin Organic Crystals on Graphene for High-Efficiency Phototransistors. (United States)

    Liu, Xiaolong; Luo, Xiaoguang; Nan, Haiyan; Guo, Hui; Wang, Peng; Zhang, Linglong; Zhou, Minmin; Yang, Ziyi; Shi, Yi; Hu, Weida; Ni, Zhenhua; Qiu, Teng; Yu, Zongfu; Xu, Jian-Bin; Wang, Xinran


    Epitaxially grown ultrathin organic semiconductors on graphene show great promise as highly efficient phototransistors. The devices exhibit a strong photoresponse down to the limit of a monolayer organic crystal, with a photoresponsivity higher than 10(4) A W(-1) and a photoconductive gain over 10(8) . The excellent performance is attributed to the high quality of the organic crystal and interface, a unique feature of van der Waals epitaxy.

  16. Enhancement of Available Conversion Efficiency of Optical Parametric Amplifier in a Cascaded Photonic Crystal Structure

    Institute of Scientific and Technical Information of China (English)

    LI Wen-Hui; CHEN Li-Xue; TANG Dong-Hua; DING Wei-Qiang; LIU Shu-Tian


    @@ Using the cascaded structure of a linear and a second-order nonlinear photonic crystals, we realize a high-efficiency optical parametric amplifier in the case of exact phase matching. This proposal is verified using the slow-envelope nonlinear finite difference time domain numerical method. Compared with the case of the individual nonlinear photonic crystal structure, the oscillation threshold is decreased obviously, and the peak power amplification factor of the transmitted signal is enhanced more than 20 times.

  17. High efficiency multi-pass proton beam extraction with a bent crystal at the SPS (United States)

    Altuna, X.; Bussa, M. P.; Carboni, G.; Dehning, B.; Elsener, K.; Ferrari, A.; Fidecaro, G.; Freund, A.; Guinand, R.; Gyr, M.; Herr, W.; Klem, J.; Laffin, M.; Lanceri, L.; Mikkelsen, U.; Møller, S. P.; Scandale, W.; Tosello, F.; Uggerhøj, E.; Vuagnin, G.; Weisse, E.; Weisz, S.


    Recent measurements of 120 GeV proton extraction by means of a bent silicon crystal at the CERN-SPS accelerator are summarized. The existence of multi-pass extraction has been proven by blocking first-pass extraction: using a crystal covered with an amorphous layer, extracted beam with high efficiency was observed, which provides a direct proof for the importance of the multi-pass mechanism. This opens new possibilities in the design and optimization of a bent crystal extraction scheme.

  18. Efficient 266 nm Ultraviolet Beam Generation in K2Al2B2O7 Crystal

    Institute of Scientific and Technical Information of China (English)

    吕军华; 王桂玲; 许祖彦; 陈创天; 王继扬; 张承乾; 刘耀岗


    The ultraviolet beam at 266 nm was obtained by fourth harmonic generation of 1064 nm Nd:YAG laser radiation through a nonlinear crystal K2Al2 B2O7 (KABO). The fundamental frequency of a Hash-lamp pumped Nd: YAG laser was doubled in a β-Ba2B2O4 crystal to generate a second harmonic output at the wavelength of 532 nm,and then doubled again in the KABO crystal to generate the fourth harmonic output at 266 nm. The optical conversion efficiency from 532 to 266 nm was investigated for the first time, and 13% was achieved.

  19. Optical simulation of in-plane-switching blue phase liquid crystal display using the finite-difference time-domain method (United States)

    Dou, Hu; Ma, Hongmei; Sun, Yu-Bao


    The finite-difference time-domain method is used to simulate the optical characteristics of an in-plane switching blue phase liquid crystal display. Compared with the matrix optic methods and the refractive method, the finite-difference time-domain method, which is used to directly solve Maxwell’s equations, can consider the lateral variation of the refractive index and obtain an accurate convergence effect. The simulation results show that e-rays and o-rays bend in different directions when the in-plane switching blue phase liquid crystal display is driven by the operating voltage. The finite-difference time-domain method should be used when the distribution of the liquid crystal in the liquid crystal display has a large lateral change. Project supported by the National Natural Science Foundation of China (Grant Nos. 11304074, 61475042, and 11274088), the Natural Science Foundation of Hebei Province, China (Grant Nos. A2015202320 and GCC2014048), and the Key Subject Construction Project of Hebei Province University, China.

  20. Chelant-induced reclamation of indium from the spent liquid crystal display panels with the aid of microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Hiroshi, E-mail: [Institute of Science and Engineering, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan); Rahman, Ismail M.M., E-mail: [Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan); Department of Applied and Environmental Chemistry, University of Chittagong, Chittagong 4331 (Bangladesh); Egawa, Yuji; Sawai, Hikaru; Begum, Zinnat A. [Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan); Maki, Teruya [Institute of Science and Engineering, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan); Mizutani, Satoshi [Graduate School of Engineering, Osaka City University, Sugimoto 3-3-138, Sumiyoshi-Ku, Osaka 558-8585 (Japan)


    Highlights: • A new process for indium recovery from end-of-life LCD panels. • Chelants are used for the dissolution of indium from the waste LCD panels. • Indium extraction with chelant is enhanced with the aid of microwave irradiation. • Extraction rate is quantitative in the hyperbaric high-temperature environment. -- Abstract: Indium is a rare metal that is mostly consumed as indium tin oxide (ITO) in the fabrication process of liquid crystal display (LCD) panels. The spent LCD panels, termed as LCD-waste hereafter, is an increasing contributor of electronic waste burden worldwide and can be an impending secondary source of indium. The present work reports a new technique for the reclamation of indium from the unground LCD-waste using aminopolycarboxylate chelants (APCs) as the solvent in a hyperbaric environment and at a high-temperature. Microwave irradiation was used to create the desired system conditions, and a substantial abstraction of indium (≥80%) from the LCD-waste with the APCs (EDTA or NTA) was attained in the acidic pH region (up to pH 5) at the temperature of ≥120 °C and the pressure of ∼50 bar. The unique point of the reported process is the almost quantitative recovery of indium from the LCD-waste that ensured via the combination of the reaction facilitatory effect of microwave exposure and the metal extraction capability of APCs. A method for the selective isolation of indium from the extractant solution and recycle of the chelant in solution is also described.

  1. Leaching of indium from obsolete liquid crystal displays: Comparing grinding with electrical disintegration in context of LCA

    Energy Technology Data Exchange (ETDEWEB)

    Dodbiba, Gjergj, E-mail: [Department of System Innovation, Graduate School of Engineering, University of Tokyo (Japan); Nagai, Hiroki; Wang Lipang; Okaya, Katsunori; Fujita, Toyohisa [Department of System Innovation, Graduate School of Engineering, University of Tokyo (Japan)


    Highlights: Black-Right-Pointing-Pointer Two pre-treatment methods, prior to leaching of indium from obsolete LCD modules, were described. Black-Right-Pointing-Pointer Conventional grinding and electrical disintegration have been evaluated and compared in the context of LCA. Black-Right-Pointing-Pointer Experimental data on the leaching capacity for indium and the electricity consumption of equipment were inputted into the LCA model in order to compare the environmental performance of each method. Black-Right-Pointing-Pointer An estimate for the environmental performance was calculated as the sum of six impact categories. Black-Right-Pointing-Pointer Electrical disintegration method outperforms conventional grinding in all impact categories. - Abstract: In order to develop an effective recycling system for obsolete Liquid Crystal Displays (LCDs), which would enable both the leaching of indium (In) and the recovery of a pure glass fraction for recycling, an effective liberation or size-reduction method would be an important pre-treatment step. Therefore, in this study, two different types of liberation methods: (1) conventional grinding, and (2) electrical disintegration have been tested and evaluated in the context of Life Cycle Assessment (LCA). In other words, the above-mentioned methods were compared in order to find out the one that ensures the highest leaching capacity for indium, as well as the lowest environmental burden. One of the main findings of this study was that the electrical disintegration was the most effective liberation method, since it fully liberated the indium containing-layer, ensuring a leaching capacity of 968.5 mg-In/kg-LCD. In turn, the estimate for the environmental burden was approximately five times smaller when compared with the conventional grinding.

  2. Efficient femtosecond mid-infrared pulse generation by dispersivewave radiation in bulk lithium niobate crystal

    DEFF Research Database (Denmark)

    Zhou, Binbin; Guo, Hairun; Bache, Morten


    We experimentally demonstrate efficient mid-infrared pulse generation by dispersive wave radiation in bulk lithium niobate crystal. Femtosecond mid-IR pulses centering from 2.8–2.92 µm are generated using the single pump wavelengths from 1.25–1.45 µm.......We experimentally demonstrate efficient mid-infrared pulse generation by dispersive wave radiation in bulk lithium niobate crystal. Femtosecond mid-IR pulses centering from 2.8–2.92 µm are generated using the single pump wavelengths from 1.25–1.45 µm....

  3. Review of Display Technologies Focusing on Power Consumption

    Directory of Open Access Journals (Sweden)

    María Rodríguez Fernández


    Full Text Available This paper provides an overview of the main manufacturing technologies of displays, focusing on those with low and ultra-low levels of power consumption, which make them suitable for current societal needs. Considering the typified value obtained from the manufacturer’s specifications, four technologies—Liquid Crystal Displays, electronic paper, Organic Light-Emitting Display and Electroluminescent Displays—were selected in a first iteration. For each of them, several features, including size and brightness, were assessed in order to ascertain possible proportional relationships with the rate of consumption. To normalize the comparison between different display types, relative units such as the surface power density and the display frontal intensity efficiency were proposed. Organic light-emitting display had the best results in terms of power density for small display sizes. For larger sizes, it performs less satisfactorily than Liquid Crystal Displays in terms of energy efficiency.

  4. Low cost, single crystal-like substrates for practical, high efficiency solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, A.; Specht, E.D.; List, F.A. [and others


    It is well established that high efficiency (20%) solar cells can be routinely fabricated using single crystal photovoltaic (PV) materials with low defect densities. Polycrystalline materials with small grain sizes and no crystallographic texture typically result in reduced efficiences. This has been ascribed primarily to the presence of grain boundaries and their effect on recombination processes. Furthermore, lack of crystallographic texture can result in a large variation in dopant concentrations which critically control the electronic properties of the material. Hence in order to reproducibly fabricate high efficiency solar cells a method which results in near single crystal material is desirable. Bulk single crystal growth of PV materials is cumbersome, expensive and difficult to scale up. We present here a possible route to achieve this if epitaxial growth of photovoltaic materials on rolling-assisted-biaxially textured-substrates (RABiTS) can be achieved. The RABiTS process uses well-established, industrially scaleable, thermomechanical processing to produce a biaxially textured or single-crystal-like metal substrate with large grains (50-100 {mu}m). This is followed by epitaxial growth of suitable buffer layers to yield chemically and structurally compatible surfaces for epitaxial growth of device materials. Using the RABiTS process it should be possible to economically fabricate single-crystal-like substrates of desired sizes. Epitaxial growth of photovoltaic devices on such substrates presents a possible route to obtaining low-cost, high performance solar cells.

  5. Record Deflection Efficiencies Measured for High Energy Protons in a Bent Germanium Crystal (United States)

    Elsener, K.; Biino, C.; Clement, M.; Doble, N.; Gatignon, L.; Grafstrom, P.; Mikkelsen, U.; Kirsebom, K.; Møller, S. P.; Uggerhøj, E.; Worm, T.; Freund, A.


    New experimental results on the deflection of 450 GeV/c and 200 GeV/c protons in a bent Ge crystal are presented. At 450 GeV/c, the 50 mm long crystal gave record deflection efficiencies up to 60% for small angles (1 mrad), while at angles as large as 12 mrad, the efficiency is about 25 times larger than for a silicon crystal of the same size. Measurements up to 20 mrad deflection angle have been performed at 200 GeV/c as well as 450 GeV/c - the lower bending dechanneling leads to a rather slow decrease in efficiency at lower momenta, and 15% of the 200 GeV/c beam hitting the crystal are still deflected at the largest angles measured. These experimental results are in good agreement with a model for channeling deflection developed by Ellison and give confidence in extrapolations to higher energies (e.g. to LHC), other crystal materials or different deflection angles.

  6. High-efficiency broadband anti-Stokes emission from Yb3+-doped bulk crystals. (United States)

    Zhu, Siqi; Wang, Chunhao; Li, Zhen; Jiang, Wei; Wang, Yichuan; Yin, Hao; Wu, Lidan; Chen, Zhenqiang; Zhang, Ge


    We investigate the broadband anti-Stokes emission (BASE) from Yb3+-doped crystals with a laser diode (LD) pumping at 940 nm. Our experiment reveals that Yb3+-doped crystals with random cracks are able to generate bright BASE at room temperature and atmospheric pressure. By examining the various characteristics of the crystals and the emitted light, we supply a theory for interpreting the underlying physics for this variety of BASE. In particular, we take into consideration the effects of energy migration, avalanche process, and charge-transfer luminescence. This represents the first time, to the best of our knowledge, that BASE was obtained from Yb3+-doped bulk crystals with a high optical-optical efficiency.

  7. Design of 1-μm-pitch liquid crystal spatial light modulators having dielectric shield wall structure for holographic display with wide field of view (United States)

    Isomae, Yoshitomo; Shibata, Yosei; Ishinabe, Takahiro; Fujikake, Hideo


    In the development of electronic holographic displays with a wide field of view, one issue is the realization of 1-μm-pitch spatial light modulators (SLMs) using liquid crystal on silicon (LCOS) techniques. We clarified that it is necessary to suppress not only the leakage of fringe electric fields from adjacent pixels but also the effect of elastic forces in the liquid crystal to achieve full-phase modulation (2π) in individual pixels. We proposed a novel LCOS-SLM with a dielectric shield wall structure, and achieved driving of individual 1-μm-pitch pixels. We also investigated the optimum values for width and dielectric constant of the wall structure when enlarging the area that can modulate light in the pixels. These results contribute to the design of 1-μm-pitch LCOS-SLM devices for wide-viewing-angle holographic displays.

  8. Highly efficient optical filter based on vertically coupled photonic crystal cavity and bus waveguide (United States)

    Debnath, Kapil; Welna, Karl; Ferrera, Marcello; Deasy, Kieran; Lidzey, David G.; O'Faolain, Liam


    We experimentally demonstrate a new optical filter design based on a vertically coupled photonic crystal cavity and a bus waveguide monolithically integrated on the silicon on insulator platform. The use of a vertically coupled waveguide gives flexibility in the choice of the waveguide material and dimensions, dramatically lowering the insertion loss while achieving very high coupling efficiencies to wavelength scale resonators

  9. Highly efficient optical filter based on vertically coupled Photonic crystal cavity and bus waveguide

    CERN Document Server

    Debnath, Kapil; Ferrera, Marcello; Deasy, Kieran; Lidzey, David G; O'Faolain, Liam


    We experimentally demonstrate a new optical filter design based on a vertically coupled photonic crystal cavity and a bus waveguide monolithically integrated on the silicon on insulator platform. The use of a vertically coupled waveguide gives flexibility in the choice of the waveguide material and dimensions, dramatically lowering the insertion loss while achieving very high coupling efficiencies to wavelength scale resonators

  10. Optimize the modulation response of twisted-nematic liquid crystal displays as pure phase spatial light modulators (United States)

    Ma, Baiheng; Peng, Fei; Kang, Mingwu; Zhou, Jiawu


    Twisted-nematic liquid crystal displays (TN-LCD) are widely used in numerous research fields of optics working as spatial light modulators. Approaches to obtaining desired intensity or phase modulation by TN-LCD have been extensively studied based on the knowledge of TN-LCD's internal structure parameters, e.g., the orientation of LC molecules at the surfaces, the twist angle, the thickness of the LC layer, and the birefringence of the material. Generally TN-LCD placed between two linear polarizers (P) produces coupled intensity and phase modulation. To obtain the commonly used pure phase modulation, quarter wave plates (QWP) are often used in front of and/or behind the LCD. In this paper, we present a method to optimize the optical modulation properties of the TN-LCD to obtain pure phase modulation in the configuration of P-QWP-LCD-QWP-P each with proper orientation. Firstly an improved method for determining the Jones matrix of the TN-LCD without knowing its internal parameters is presented, which is based on the macroscopical Jones matrix descriptions for TN-LCD, linear polarizer and QWP. Only three sets of intensity measurements are needed for the complete determination of the TN-LCD's Jones matrix for a single wavelength. Then Jones matrix calculations are carried out to determine the orientations of the polarizers and QWPs for pure phase modulation response. In addition, we prove that the phase modulation depth (PMD) of the TN-LCD can be further increased provided that the mean intensity transmission is decreased to a lower level, which is very useful when the TN-LCD is used as a phase modulator and the ratio between the intensities of the desired diffracted order relative to the other diffracted orders is required higher. Experimental results coincide well with the optical modulation properties of the TN-LCD predicted by our determined Jones matrix. In contrast to the traditional method which requires knowledge of the TN-LCD's internal structure parameters

  11. 11% efficient single-crystal solar cells and 10% efficient polycrystalline cells made from refined metallurgical silicon

    Energy Technology Data Exchange (ETDEWEB)

    Hanoka, J.I.; Strock, H.B.; Kotval, P.S.


    Refined metallurgical silicon has been utilized as a feedstock material both for Czochralski-pulled single crystal and for cast polycrystalline silicon solar cells. Using a phosphorous diffused junction for an n on p structure, the single-crystal cells have yielded AM1 efficiencies up to 11.1%, open circuit voltages up to 596 mV, and fill factors as high as 81% (not all on the same cell). The cast polycrystalline substrates have produced cells up to 10.1% efficient (AM1) with fill factors of 79% and V/sub o/c = 585 mV. Properties of the single-crystal and polycrystalline cells are quite similar, with the principal limiting factor being J/sub s/c , which is typically 20--23 mA/cm/sup 2/. Spectral response and EBIC data indicate that a considerable amount of the recombination is due to impurities. For the cast polycrystalline cells, the electron beam induced current data shows that grain boundary recombination is significant.

  12. Photon harvesting, coloring and polarizing in photovoltaic cell integrated color filters: efficient energy routing strategies for power-saving displays. (United States)

    Wen, Long; Chen, Qin; Song, Shichao; Yu, Yan; Jin, Lin; Hu, Xin


    We describe the integral electro-optical strategies that combine the functionalities of photovoltaic (PV) electricity generation and color filtering as well as polarizing to realize more efficient energy routing in display technology. Unlike the conventional pigment-based filters and polarizers, which absorb substantial amounts of unwanted spectral components and dissipate them in the form of heat, we propose converting the energy of those photons into electricity by constructing PV cell-integrated color filters based on a selectively transmitting aluminum (Al) rear electrode perforated with nanoholes (NHs). Combining with a dielectric-metal-dielectric (DMD) front electrode, the devices were optimized to enable efficient cavity-enhanced photon recycling in the PV functional layers. We perform a comprehensive theoretical and numerical analysis to explore the extraordinary optical transmission (EOT) through the Al NHs and identify basic design rules for achieving structural coloring or polarizing in our PV color filters. We show that the addition of thin photoactive polymer layers on the symmetrically configured Al NH electrode narrows the bandwidth of the EOT-assisted high-pass light filtering due to the strongly damped anti-symmetric coupling of the surface modes excited on the front and rear surface of the Al NHs, which facilitates the whole visible coloring with relatively high purity for the devices. By engineering the cut-off characteristics of the plasmonic waveguide mode supported by the circular or ellipsoidal Al NHs, beyond the photon recycling capacity, PV color filters and PV polarizing color filters that allow polarization-insensitive and strong polarization-anisotropic color filtering were demonstrated. The findings presented here may shed some light on expanding the utilization of PV electricity generation across new-generation energy-saving electrical display devices.

  13. Efficient display of active lipase LipB52 with a Pichia pastoris cell surface display system and comparison with the LipB52 displayed on Saccharomyces cerevisiae cell surface

    Directory of Open Access Journals (Sweden)

    Ma Yushu


    Full Text Available Abstract Background For industrial bioconversion processes, the utilization of surface-displayed lipase in the form of whole-cell biocatalysts is more advantageous, because the enzymes are displayed on the cell surface spontaneously, regarded as immobilized enzymes. Results Two Pichia pastoris cell surface display vectors based on the flocculation functional domain of FLO with its own secretion signal sequence or the α-factor secretion signal sequence were constructed respectively. The lipase gene lipB52 fused with the FLO gene was successfully transformed into Pichia pastoris KM71. The lipase LipB52 was expressed under the control of the AOX1 promoter and displayed on Pichia pastoris KM71 cell surface with the two Pichia pastoris cell surface display vectors. Localization of the displayed LipB52 on the cell surface was confirmed by the confocal laser scanning microscopy (CLSM. The LipB52 displayed on the Pichia pastoris cell surface exhibited activity toward p-nitrophenol ester with carbon chain length ranging from C10 to C18, and the optimum substrate was p-nitrophenol-caprate (C10, which was consistent with it displayed on the Saccharomyces cerevisiae EBY100 cell surface. The hydrolysis activity of lipase LipB52 displayed on Pichia pastoris KM71-pLHJ047 and KM71-pLHJ048 cell surface reached 94 and 91 U/g dry cell, respectively. The optimum temperature of the displayed lipases was 40°C at pH8.0, they retained over 90% activity after incubation at 60°C for 2 hours at pH 7.0, and still retained 85% activity after incubation for 3 hours. Conclusion The LipB52 displayed on the Pichia pastoris cell surface exhibited better stability than the lipase LipB52 displayed on Saccharomyces cerevisiae cell surface. The displayed lipases exhibited similar transesterification activity. But the Pichia pastoris dry cell weight per liter (DCW/L ferment culture was about 5 times than Saccharomyces cerevisiae, the lipase displayed on Pichia pastoris are more

  14. Long-lived and highly efficient green and blue phosphorescent emitters and device architectures for OLED displays (United States)

    Eickhoff, Christian; Murer, Peter; Geßner, Thomas; Birnstock, Jan; Kröger, Michael; Choi, Zungsun; Watanabe, Soichi; May, Falk; Lennartz, Christian; Stengel, Ilona; Münster, Ingo; Kahle, Klaus; Wagenblast, Gerhard; Mangold, Hannah


    In this paper, two OLED device concepts are introduced. First, classical phosphorescent green carbene emitters with unsurpassed lifetime, combined with low voltage and high efficiency are presented and the associated optimized OLED stacks are explained. Second, a path towards highly efficient, long-lived deep blue systems is shown. The high efficiencies can be reached by having the charge-recombination on the phosphorescent carbene emitter while at the same time short emissive lifetimes are realized by fast energy transfer to the fluorescent emitter, which eventually allows for higher OLED stability in the deep blue. Device architectures, materials and performance data are presented showing that carbene type emitters have the potential to outperform established phosphorescent green emitters both in terms of lifetime and efficiency. The specific class of green emitters under investigation shows distinctly larger electron affinities (2.1 to 2.5 eV) and ionization potentials (5.6 to 5.8 eV) as compared to the "standard" emitter Ir(ppy)3 (5.0/1.6 eV). This difference in energy levels requires an adopted OLED design, in particular with respect to emitter hosts and blocking layers. Consequently, in the diode setup presented here, the emitter species is electron transporting or electron trapping. For said green carbene emitters, the typical peak wavelength is 525 nm yielding CIE color coordinates of (x = 0.33, y = 0.62). Device data of green OLEDs are shown with EQEs of 26 %. Driving voltage at 1000 cd/m2 is below 3 V. In an optimized stack, a device lifetime of LT95 > 15,000 h (1000 cd/m2) has been reached, thus fulfilling AMOLED display requirements.

  15. Single-crystal charge transfer interfaces for efficient photonic devices (Conference Presentation) (United States)

    Alves, Helena; Pinto, Rui M.; Maçôas, Ermelinda M. S.; Baleizão, Carlos; Santos, Isabel C.


    Organic semiconductors have unique optical, mechanical and electronic properties that can be combined with customized chemical functionality. In the crystalline form, determinant features for electronic applications such as molecular purity, the charge mobility or the exciton diffusion length, reveal a superior performance when compared with materials in a more disordered form. Combining crystals of two different conjugated materials as even enable a new 2D electronic system. However, the use of organic single crystals in devices is still limited to a few applications, such as field-effect transistors. In 2013, we presented the first system composed of single-crystal charge transfer interfaces presenting photoconductivity behaviour. The system composed of rubrene and TCNQ has a responsivity reaching 1 A/W, corresponding to an external quantum efficiency of nearly 100%. A similar approach, with a hybrid structure of a PCBM film and rubrene single crystal also presents high responsivity and the possibility to extract excitons generated in acceptor materials. This strategy led to an extended action towards the near IR. By adequate material design and structural organisation of perylediimides, we demonstrate that is possible to improve exciton diffusion efficiency. More recently, we have successfully used the concept of charge transfer interfaces in phototransistors. These results open the possibility of using organic single-crystal interfaces in photonic applications.

  16. Ultrahigh-efficiency apodized grating coupler using fully etched photonic crystals

    DEFF Research Database (Denmark)

    Ding, Yunhong; Ou, Haiyan; Peucheret, Christophe


    We present an efficient method to design apodized grating couplers with Gaussian output profiles for efficient coupling between standard single mode fibers and silicon chips. An apodized grating coupler using fully etched photonic crystal holes on the silicon-on-insulator platform is designed......, and fabricated in a single step of lithography and etching. An ultralow coupling loss of x2212;1.74x2009;x2009;dB (67% coupling efficiency) with a 3xA0;dB bandwidth of 60xA0;nm is experimentally measured....

  17. High light-extraction-efficiency OLED based on photonic crystal slab structures with taper unit cells

    Institute of Scientific and Technical Information of China (English)

    YAN Rong-jin; WANG Qing-kang


    To improve the light-extraction-efficiency of OLED,we introduced PCS (Photonic Crystal Slab) structures into the interface of ITO layer and glass substrate.PCS structures with Taper unit cells are proved to be effective in reducing the energy of guided wave trapped in high refractive index material,and an increase of light-extraction-efficiency to 95.26% is gained.This enhancement is much greater than the traditional PCS with cylinder unit cells (60%-70%).Physical mechanisms of light-extraction-efficiency enhancement in these structures are further discussed.

  18. High efficiency cholesteric liquid crystal lasers with an external stable resonator. (United States)

    Shirvani-Mahdavi, Hamidreza; Fardad, Shima; Mohajerani, Ezeddin; Wu, Shin-Tson


    An amplified cholesteric liquid crystal (CLC) laser performance is demonstrated by utilizing a binary-dye mixture (with 62 wt% DCM and 38 wt% PM597) as the active medium and an external stable resonator. The measured results show that the laser efficiency is enhanced as compared to the highest efficiency of each individual dye. Furthermore, using such an active CLC in an external stable resonator leads to a approximately 92X improved efficiency over the single CLC laser. In this instance, the binary-dye doped CLC simultaneously functions as laser oscillator and amplifier.

  19. High-density grids for efficient data collection from multiple crystals

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Elizabeth L.; Aguila, Laura; Alonso-Mori, Roberto; Barnes, Christopher O.; Bonagura, Christopher A.; Brehmer, Winnie; Brunger, Axel T.; Calero, Guillermo; Caradoc-Davies, Tom T.; Chatterjee, Ruchira; Degrado, William F.; Fraser, James S.; Ibrahim, Mohamed; Kern, Jan; Kobilka, Brian K.; Kruse, Andrew C.; Larsson, Karl M.; Lemke, Heinrik T.; Lyubimov, Artem Y.; Manglik, Aashish; McPhillips, Scott E.; Norgren, Erik; Pang, Siew S.; Soltis, S. M.; Song, Jinhu; Thomaston, Jessica; Tsai, Yingssu; Weis, William I.; Woldeyes, Rahel A.; Yachandra, Vittal; Yano, Junko; Zouni, Athina; Cohen, Aina E.


    Higher throughput methods to mount and collect data from multiple small and radiation-sensitive crystals are important to support challenging structural investigations using microfocus synchrotron beamlines. Furthermore, efficient sample-delivery methods are essential to carry out productive femtosecond crystallography experiments at X-ray free-electron laser (XFEL) sources such as the Linac Coherent Light Source (LCLS). To address these needs, a high-density sample grid useful as a scaffold for both crystal growth and diffraction data collection has been developed and utilized for efficient goniometer-based sample delivery at synchrotron and XFEL sources. A single grid contains 75 mounting ports and fits inside an SSRL cassette or uni-puck storage container. The use of grids with an SSRL cassette expands the cassette capacity up to 7200 samples. Grids may also be covered with a polymer film or sleeve for efficient room-temperature data collection from multiple samples. New automated routines have been incorporated into theBlu-Ice/DCSSexperimental control system to support grids, including semi-automated grid alignment, fully automated positioning of grid ports, rastering and automated data collection. Specialized tools have been developed to support crystallization experiments on grids, including a universal adaptor, which allows grids to be filled by commercial liquid-handling robots, as well as incubation chambers, which support vapor-diffusion and lipidic cubic phase crystallization experiments. Experiments in which crystals were loaded into grids or grown on grids using liquid-handling robots and incubation chambers are described. Crystals were screened at LCLS-XPP and SSRL BL12-2 at room temperature and cryogenic temperatures.

  20. Improvement of diffraction efficiency of three-dimensional magneto-optic spatial light modulator with magnetophotonic crystal

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, K.; Takagi, H., E-mail:; Lim, P. B.; Inoue, M., E-mail: [Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441 8580 (Japan); Goto, Taichi [Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441 8580 (Japan); JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan); Horimai, H. [HolyMine Corporation, Atsugi, Kanagawa 243 0813 (Japan); Yoshikawa, H. [Department of Computer Engineering, College of Science and Technology, Nihon University, Funabashi, Chiba 274 8501 (Japan); Bove, V. M. [MIT Media Lab, Cambridge, Massachusetts 02139 (United States)


    We have developed three-dimensional magneto-optic spatial light modulators (3D-MOSLMs) that use magnetic domains as submicron scale pixels to represent holograms. Our display system uses a submicron-scale magnetic pixel array on an amorphous TbFe film to create a wide viewing angle hologram. However, in previous work the reconstructed images had a low intensity and a low optical contrast; brightness of the reconstructed image was 4.4 × 10{sup −2 }cd/m{sup 2} with 532 nm illumination light at 10.8 mW/cm{sup 2}, while display standard ISO13406 recommends 100 cd/m{sup 2} or more. In this paper, we describe our development of a 3D-MOSLM composed of an artificial magnetic lattice structure of magnetophotonic crystals (MPCs). The MPCs enhance the diffraction efficiency of reconstructed 3D images and reduce the power consumption for controlling the magnetic pixels by a light localization effect. We demonstrate reconstructed 3D images using the MPC and show significant brightness improvement.

  1. Efficient light coupling into a photonic crystal waveguide with flatband slow mode

    CERN Document Server

    Säynätjoki, A; Mulot, M; Cassagne, D; Ahopelto, J; Lipsanen, H


    We design an efficient coupler to transmit light from a strip waveguide into the flatband slow mode of a photonic crystal waveguide with ring-shaped holes. The coupler is a section of a photonic crystal waveguide with a higher group velocity, obtained by different ring dimensions. We demonstrate coupling efficiency in excess of 95% over the 8 nm wavelength range where the photonic crystal waveguide exhibits a quasi constant group velocity vg = c/37. An analysis based on the small Fabry-P\\'erot resonances in the simulated transmission spectra is introduced and used for studying the effect of the coupler length and for evaluating the coupling efficiency in different parts of the coupler. The mode conversion efficiency within the coupler is more than 99.7% over the wavelength range of interest. The parasitic reflectance in the coupler, which depends on the propagation constant mismatch between the slow mode and the coupler mode, is lower than 0.6% within this wavelength range.

  2. Efficient transparent thin dye solar cells based on highly porous 1D photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Colodrero, Silvia; Lopez-Lopez, Carmen; Miguez, Hernan [Instituto de Ciencia de Materiales de Sevilla (CSIC-US), Centro de Investigaciones Cientificas Isla de la Cartuja, C/Americo Vespucio 49, 41092 Sevilla (Spain); Forneli, Amparo; Pelleja, Laia [Institute of Chemical Research of Catalonia (ICIQ) Avda., Paisos Catalans 16, 43007 Tarragona (Spain); Palomares, Emilio [Institute of Chemical Research of Catalonia (ICIQ) Avda., Paisos Catalans 16, 43007 Tarragona (Spain); Institucio Catalana de Recerca i Estudis Avancats (ICREA), Avda. Lluis Companys 23, 08010 Barcelona (Spain)


    A working electrode design based on a highly porous 1D photonic crystal structure that opens the path towards high photocurrents in thin, transparent, dye-sensitized solar cells is presented. By enlarging the average pore size with respect to previous photonic crystal designs, the new working electrode not only increases the device photocurrent, as predicted by theoretical models, but also allows the observation of an unprecedented boost of the cell photovoltage, which can be attributed to structural modifications caused during the integration of the photonic crystal. These synergic effects yield conversion efficiencies of around 3.5% by using just 2 {mu}m thick electrodes, with enhancements between 100% and 150% with respect to reference cells of the same thickness. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Efficient calcium lactate production by fermentation coupled with crystallization-based in situ product removal. (United States)

    Xu, Ke; Xu, Ping


    Lactic acid is a platform chemical with various industrial applications, and its derivative, calcium lactate, is an important food additive. Fermentation coupled with in situ product removal (ISPR) can provide more outputs with high productivity. The method used in this study was based on calcium lactate crystallization. Three cycles of crystallization were performed during the fermentation course using a Bacillus coagulans strain H-1. As compared to fed-batch fermentation, this method showed 1.7 times higher average productivity considering seed culture, with 74.4% more L-lactic acid produced in the fermentation with ISPR. Thus, fermentation coupled with crystallization-based ISPR may be a biotechnological alternative that provides an efficient system for production of calcium lactate or lactic acid.

  4. Identification of Text and Symbols on a Liquid Crystal Display Part I: Characterisation of the Luminance, Temporal and Spectral Characteristics (United States)


    Association of Physicists in Medicine set up the AAPM Task Group 18 to establish standards for medical displays, and this group recommended that luminance...Using CRT-Generated Stimuli. Color Research and Application, 24(3), 164-176. TG18, A. (2005). AAPM On-Line Report No. 03. Assessment of Display...for Medical Imaging Systems: Executive Summary of AAPM TG18 Report. Medical Physics, 32(4), 1205-1225. 29 DSTO-TN-0770 30 Appendix A

  5. Design of an efficient terahertz source using triply resonant nonlinear photonic crystal cavities. (United States)

    Burgess, Ian B; Zhang, Yinan; McCutcheon, Murray W; Rodriguez, Alejandro W; Bravo-Abad, Jorge; Johnson, Steven G; Loncar, Marko


    We propose a scheme for efficient cavity-enhanced nonlinear THz generation via difference-frequency generation (DFG) processes using a triply resonant system based on photonic crystal cavities. We show that high nonlinear overlap can be achieved by coupling a THz cavity to a doubly-resonant, dual-polarization near-infrared (e.g. telecom band) photonic-crystal nanobeam cavity, allowing the mixing of three mutually orthogonal fundamental cavity modes through a chi((2)) nonlinearity. We demonstrate through coupled-mode theory that complete depletion of the pump frequency - i.e., quantum-limited conversion - is possible. We show that the output power at the point of optimal total conversion efficiency is adjustable by varying the mode quality (Q) factors.

  6. Temperature sensitivity of Cu K(alpha) imaging efficiency using a spherical Bragg reflecting crystal

    Energy Technology Data Exchange (ETDEWEB)

    Akli, K U; Key, M H; Chung, H K; Hansen, S B; Freeman, R R; Chen, M H; Gregori, G; Hatchett, S; Hey, D; Izumi, N; King, J A; Kuba, J; Norreys, P; Mackinnon, A J; Murphy, C D; Snavely, R; Stepehens, R; Stoeckel, C; Theobald, W; Zhang, B


    The Vulcan laser facility at the Rutherford Appleton Laboratory was used to study the interaction of a 75 J 10 ps, high intensity laser beam with low-mass solid, Cu targets. Two instruments were fielded as diagnostics of the Cu K-shell emission from the targets: A single photon counting CCD spectrometer provided the absolute K{sub {alpha}} yield and a spherically bent Bragg crystal recorded 2D monochromatic images with a spatial resolution of 10 {micro}m. Due to the shifting and broadening of the K{sub {alpha}} spectral lines with increasing temperature, there is a temperature dependence of the crystal collection efficiency. This provides a temperature diagnostic when cross calibrated against a single hit CCD spectrometer, and it affects measurements of the spatial pattern of electron transport. The experimental data showing changing collection efficiency are presented. The results are discussed in light of modeling of the temperature-dependent spectrum of Cu K-shell emission.

  7. Generation of efficient THz radiation by optical rectification in DAST crystal using tunable femtosecond laser pulses (United States)

    Venkatesh, Mottamchetty; Thirupugalmani, K.; Rao, K. S.; Brahadeeswaran, S.; Chaudhary, A. K.


    We report the efficient THz generation by optical rectification from an indigenously grown organic DAST crystal using the 140 fs oscillator laser pulses tunable in between 780 and 850 nm. The generated THz pulse profile and powers have been measured using the photoconductive (PC) antennas and pyroelectric detector, respectively. The highest THz peak amplitude and power is obtained at 825 nm central wavelength. We have theoretically explained the enhancement of THz radiation based on the matching of average optical group refractive index and average THz refractive index of the DAST crystal at 825 nm. In addition, the dependence of THz peak amplitude and THz power on laser power have been carried out. The measured quantum conversion efficiency (QCE) of 0.5 and 1.5 THz bands are of the order 3.7 × 10-3, 1.4 × 10-3, respectively. Finally, an attempt has been made to study the effect of polarizations on generated THz signal.

  8. Improving the intensity and efficiency of compressed echo in rare-earth-ion-doped crystal (United States)

    Xiu-Rong, Ma; Yu-Qing, Liang; Song, Wang; Shuang-Gen, Zhang; Yun-Long, Shan


    We investigate the intensity and efficiency of a compressed echo, which is important in arbitrary waveform generation (AWG). A new model of compressed echo is proposed based on the optical Bloch equations, which exposes much more detailed parameters than the conventional model, such as the time delay of the chirp lasers, the nature of the rare-earth-ion-doped crystal, etc. According to the novel model of compressed echo, we find that reducing the time delay of the chirp lasers and scanning the lasers around the center frequency of the inhomogeneously broadened spectrum, while utilizing a crystal with larger coherence time and excitation lifetime can improve the compressed echo’s intensity and efficiency. The theoretical analysis is validated by numerical simulations. Project supported by Special Funds for Scientific and Technological Innovation Projects in Tianjin, China (Grant No. 10FDZDGX00400) and the Tianjin Research Program of Application Foundation and Advanced Technology, China (Grant No. 15JCQNJC01100).

  9. Efficient generation of linearly polarized Cerenkov radiation in a photonic crystal fiber with suspended rectangle core (United States)

    Luo, Xing; Cheng, Lan; Peng, Jinggang; Yang, Luyun; Dai, Nengli; Li, Haiqing; Li, Jinyan


    We report high efficiency linearly polarized Cerenkov radiation (CR) generation in a photonic crystal fiber with suspended rectangle core. The frequency up-conversion via the Cerenkov radiation upon pumping of Yb-doped femtosecond fiber laser is discussed in details. Experiment results show that the output spectrum contains, besides the infrared supercontinuum, intense green Cerenkov radiation around 536 nm, which carry about 43% of the pump energy at best. The influence of the high birefringence and dispersion character on the Cerenkov radiation generation is discussed. Experiment and simulation results indicate that the rectangle core photonic crystal fiber acts like single-mode single-polarization fiber at the pump wavelength. Only the pulse component along with the slow axis could be confined in the rectangle core well and release Cerenkov radiation efficiently. The Output green Cerenkov radiation is also demonstrated to be linearly polarized. Experiments results agree well with the theoretical predictions.

  10. Efficient terahertz wave generation from GaP crystals pumped by chirp-controlled pulses from femtosecond photonic crystal fiber amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jiang; Shi, Junkai; Xu, Baozhong; Xing, Qirong; Wang, Chingyue [Ultrafast Laser Laboratory, College of Precision Instrument and Optoelectronics Engineering, Key Laboratory of Optoelectronic Information Technology (Ministry of Education), Tianjin University, Tianjin 300072 (China); Chai, Lu, E-mail:, E-mail:; Liu, Bowen; Hu, Minglie; Li, Yanfeng, E-mail:, E-mail: [Ultrafast Laser Laboratory, College of Precision Instrument and Optoelectronics Engineering, Key Laboratory of Optoelectronic Information Technology (Ministry of Education), Tianjin University, Tianjin 300072 (China); MOEMS Key Laboratory (Ministry of Education), Tianjin University, Tianjin 300072 (China); Fedotov, Andrey B. [Physics Department, Russian Quantum Center, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Zheltikov, Aleksei M. [Physics Department, Russian Quantum Center, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States)


    A chirp-tunable femtosecond 10 W, 42 MHz photonic-crystal-fiber oscillator-amplifier system that is capable of delivering sub-60 fs light pulses at 1040 nm is used to demonstrate high-efficiency terahertz radiation generation via optical rectification in GaP crystals only a few millimeters in length. The optimization of the chirp of the fiber-laser pulses is shown to radically enhance the terahertz output, indicating one possible way to more efficiently use these extended nonlinear crystals in compact fiber-pumped terahertz radiation sources.

  11. The x-ray reflection efficiencies of planes (III) in germanium silicon and fluorite analyzing crystals. Experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez Polonio, J.


    Integrated and peak reflection efficiency curves relative to a LiF crystal are presented. K{sub {alpha}} fluorescent radiations between (22) Ti and (41) Nb were used for both germanium and silicon crystals: the interval was extended to CaK{sub {alpha}} radiation in the short wavelength region with the fluorite crystal. Reflection efficiency curves show sharp declines in the region around the K absorption edges of germanium and calcium. For CuK{sub {alpha}} radiation, the experimental reflection efficiencies at the peak for germanium, silicon and fluorite crystals are 52, 38.5 and 17 percent, whereas the integrated reflection efficiencies are 65.5, 38 and 14 percent respectively. The data were obtained from untreated crystals, using a standard Norelco non-focussing X-ray spectrometer. Experimental procedures are presented. Some considerations about the (222) missing reflections are made. (Author) 12 refs.

  12. Efficient parametric interactions in a low loss GaInP photonic crystal waveguide

    DEFF Research Database (Denmark)

    Cestier, I.; Willinger, A.; Colman, Pierre


    We describe time domain characterizations of dynamic four-wave mixing in a low loss modified W1 GaInP photonic crystal waveguide. Using 32 ps wide pump pulses with peak powers of up to 1:1W we achieved a very large conversion efficiency of ?6:8 dB as well as a 1:3 dB parametric gain experienced b...

  13. Efficient parametric interactions in a low loss GaInP photonic crystal waveguide. (United States)

    Cestier, I; Willinger, A; Colman, P; Combrié, S; Lehoucq, G; De Rossi, A; Eisenstein, G


    We describe time domain characterizations of dynamic four-wave mixing in a low loss modified W1 GaInP photonic crystal waveguide. Using 32 ps wide pump pulses with peak powers of up to 1.1 W we achieved a very large conversion efficiency of -6.8 dB as well as a 1.3 dB parametric gain experienced by a weak CW probe signal. Time domain simulations confirm quantitatively all the measured results.

  14. Enhancement of light extraction efficiency in OLED with two-dimensional photonic crystal slabs

    Institute of Scientific and Technical Information of China (English)

    Rongjin Yan; Qingkang Wang


    Light extraction efficiency of organic light emitting diode (OLED) based on various photonic crystal slab (PCS) structures was studied. By using the finite-difference time-domain (FDTD) method, we investigated the effect of several parameters, including filling factor and lattice constant, on the enhancement of light extraction efficiency of three basic PCSs, and got the most effective one. Two novel designs of "interlaced"and "double-interlaced" PCS structures based on the most effective basic PCS structure were introduced,and the "interlaced" one was proved to be even more efficient than its prototype. Large enhancement of light extraction efficiency resulted from the coupling to leaky modes in the expended light cone of a band structure, the diffraction in the space between columns, as well as the strong scattering at indium-tinoxide/glass interfaces.

  15. Reduced operating voltage and grey-to-grey response time in a vertically aligned liquid crystal display using a mixture of two polyimide alignment materials (United States)

    Lee, Ji-Hoon; Choi, Young Eun; Lee, Jun Hee; Lee, Byeong Hoon; Song, Won Il; Jeong, Kwang-Un; Lee, Gi-Dong; Lee, Seung Hee


    We proposed a method to reduce the operating voltage and the grey-to-grey switching time of a vertically aligned liquid crystal display using a mixture of planar and vertical polyimide alignment materials. The surface anchoring energy of the two-polyimide mixture was smaller than that of the pure vertical polyimide and consequently, liquid crystal molecules were easily switched to a planar state with an electric field, resulting in a greater maximum retardation than that of the pure polyimide at the same applied voltage. Rising time was also significantly reduced due to the suppressed optical bouncing effect in the mixed planar polyimide, and the decaying time showed negligible change. With the proposed approach, we can reduce the cell gap to obtain half-wave retardation allowing for faster response time while keeping a low operating voltage.

  16. 基于液晶空间光调制器的全息显示∗%Holographic display based on liquid crystal spatial light mo dulator

    Institute of Scientific and Technical Information of China (English)

    夏军; 常琛亮; 雷威


    In conventional phase-only holographic display, the phase-only computer generated hologram is usually calculated based on the fast Fourier transform (FFT) algorithm, in which the Nyquist theory should be satisfied. However, due to the pixel structure of the liquid crystal spatial light modulator and a fixed spatial sampling rate, the size of the reconstructed image is limited by the space-bandwidth product of the liquid crystal phase modulator. The traditional solution is to use convolution algorithm or double-step Fresnel diffraction algorithm to calculate the Fresnel hologram, but FFT has to be calculated many times in both of the methods, thereby increasing the burden of hologram computation. Therefore, in this paper we propose a method to calculate the phase-only hologram based on setting a virtual hologram plane. This virtual hologram plane is set based on the principle of lens imaging. So the calculation of the hologram can be divided into two steps: the first step is to calculate the Fresnel diffraction from the object plane to the virtual hologram plane, and the second step is to calculate the hologram from the virtual hologram plane by being multiplied with a quadratic phase term. In this way, the hologram can be calculated from the original object with any sampling rate we need by adjusting the corresponding parameters of distance. By this method one can calculate the Fresnel diffraction between hologram plane and object plane with variable sampling rates, without considering the space-bandwidth product of the liquid crystal phase modulator, and this algorithm uses only one FFT calculation, which can speed up the calculation of hologram compared with the convolution based method (using three FFTs in calculation) and the double-step Fresnel method (using two FFTs in calculation). Both the computer simulation and the optical experiments demonstrate that the object can be reconstructed with different sizes in the holographic display system. In the optical

  17. WE-D-204-02: Novel Method for Correcting Degradation of Sharpness of Liquid-Crystal Display Based On Modulation Transfer Function

    Energy Technology Data Exchange (ETDEWEB)

    Tokurei, S [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka (Japan); Department of Radiology, Yamaguchi University Hospital, Ube, Yamaguchi (Japan); Morishita, J; Yabuuchi, H [Department of Health Sciences, Faculty of Medical Sciences, Kyushu Universi, Fukuoka, Fukuoka (Japan); Shiotsuki, K [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka (Japan); Bamba, Y; Ogaki, M; Kita, M [Eizo Corporation, Hakusan, Ishikawa (Japan)


    Purpose: To develop a method for improving sharpness of images reproduced on liquid-crystal displays (LCDs) by compensating for the degradation of modulation transfer function (MTF) of the LCD. Methods: The inherent MTF of a color LCD (display MTF) was measured using a commercially available color digital camera. The frequency responses necessary to compensate for the resolution property of the LCD were calculated from the inverses of the display MTFs in both the horizontal and vertical directions. In addition, the inverses of the display MTFs were combined with the response of the human eye. The finite impulse response (FIR) filters were computed by taking the inverse Fourier transform of the frequency responses, and the effects of the FIR filtering on both the resolution and noise properties of the displayed images were verified by measuring the MTF and Wiener spectrum (WS), respectively. The FIR filtering was then applied to the representation of digital bone and chest radiographs. Results: The FIR filtering improved the MTF values by up to almost 1.0 or greater over the frequency range of interest, while it minimally increased the WS values. Combining the inverses of the display MTFs with the response of the human eye led to further refinement of the MTF. Our method was successfully and beneficially applied to the image interpretation of bone radiographs. The resolution enhancement of chest radiographs, which include larger scattered radiation than bone radiographs, was easily perceived by incorporating the response of the human eye. In addition, no artifacts were observed on the processed images. Conclusion: Our proposed method to compensate for the degradation of the resolution properties of LCDs has the potential to improve the observer performance of radiologists when reading digital radiographs. This work was supported in part by grant from EIZO Corporation.

  18. Crystal growth and second harmonic generation efficiency of a chalcone derivative

    Energy Technology Data Exchange (ETDEWEB)

    Meenatchi, V.; Muthu, K.; Rajasekar, M.; Meenakshisundaram, SP., E-mail:


    Single crystals of (2E,6E)-2-(4-fluorobenzylidine)-6-(4-methoxybenzylidine)cyclohexanone (FBMBC) have been grown by a slow evaporation solution growth technique from ethanol at room temperature. The single crystal X-ray diffraction study reveals that the FBMBC belongs to triclinic system and the cell parameters are a=9.790(6) Å, b=12.08(7) Å, c=14.09(9) Å and V=1577 Å{sup 3}. The structure and the crystallinity of the material were further confirmed by powder X-ray diffraction analysis. The various functional groups present in the molecule are confirmed by Fourier transform infrared spectral analysis. The scanning electron microscopy study reveals the surface morphology of the as-grown crystal. Thermogravimetric/differential thermal analysis studies reveal the purity of the material and the crystals are transparent in the visible region having a low optical cut-off at ∼475 nm. The second harmonic generation efficiency of FBMBC is estimated by the Kurtz and Perry technique. Theoretical calculations were performed using the Hartree–Fock method with 6-31 G(d,p) as the basis set to derive the optimized geometry and the first-order molecular hyperpolarizability (β) values.

  19. Enhancing extraction efficiency of mid-infrared fluorescence in chalcogenide glass via photonic crystal (United States)

    Zhang, Jun; Zhang, Peiqing; Ma, Beijiao; Dai, Shixun; Zhang, Wei; Nie, Qiuhua


    The use of rare earth-doped chalcogenide glass is an attractive method to develop mid-infrared sources. In this work, Er3+-doped chalcogenide glass is prepared, and photonic crystal (PC) pattern is designed to improve the extraction efficiency of light emission from the sample surface. The finite difference time domain simulation shows that the light extraction efficiency from the sample surface can be 1.62 times stronger than that from the sample without PC structure by introducing a simple two-dimensional (2D) PC structure into glass samples. This improvement was the result of the efficient light diffraction on the surface because of the integrated 2D PC. Results in this work offer a potential in developing midinfrared light sources.

  20. Photonic crystal waveguide cavity with waist design for efficient trapping and detection of nanoparticles. (United States)

    Lin, Pin-Tso; Lu, Tsan-Wen; Lee, Po-Tsung


    For manipulating nanometric particles, we propose a photonic crystal waveguide cavity design with a waist structure to enhance resonance characteristic of the cavity. For trapping a polystyrene particle of 50 nm radius on the lateral side of the waist, the optical force can reach 2308 pN/W with 24.7% signal transmission. Threshold power of only 0.32 mW is required for stable trapping. The total length of the device is relatively short with only ten photonic crystal periods, and the trapping can occur precisely and only at the waist. The designed cavity can also provide particle detection and surrounding medium sensing using the transmission spectrum with narrow linewidth. The simulated figure of merit of 110.6 is relatively high compared with those obtained from most plasmonic structures for sensing application. We anticipate this design with features of compact, efficient, and versatile in functionality will be beneficial for developing lab-on-chip in the future.

  1. Efficient broadband sum and difference frequency generation with a single chirped quasi-phase-matching crystal

    CERN Document Server

    Rangelov, Andon A


    We propose an efficient broadband frequency generation technique for two collinear optical parametric processes $\\omega_3=\\omega_1+\\omega_2$ and $\\omega_4=\\omega_1-\\omega_2$. It exploits chirped quasi-phase-matched gratings, which in the undepleted pump approximation regime perform population transfer that is analogous to adiabatic population transfer in a three-state ``vee'' quantum system. The energy of the input fields is transferred adiabatically either into $\\omega_3$ or $\\omega_4$ field, depending on which of the two phase matchings occurs first by the local modulation period in the crystal. One can switch the output between $\\omega_3$ and $\\omega_4$ by inverting the direction of the local modulation sweep, which corresponds to a rotation of the crystal by angle $\\pi$

  2. Improving efficiency of supercontinuum generation in photonic crystal|fibers by direct degenerate four-wave-mixing

    DEFF Research Database (Denmark)

    Nikolov, Nikola Ivanov; Bang, Ole; Bjarklev, Anders Overgaard


    The efficiency of supercontinuum generation in photonic crystal fibers is significantly improved by designing the dispersion to allow widely separated spectral lines generated by degenerate four-wave-mixing directly from the pump to broaden and merge.......The efficiency of supercontinuum generation in photonic crystal fibers is significantly improved by designing the dispersion to allow widely separated spectral lines generated by degenerate four-wave-mixing directly from the pump to broaden and merge....

  3. SU-8 process optimization for high fiber coupling efficiency of liquid crystal filled photonic bandgap fiber components

    DEFF Research Database (Denmark)

    Wei, Lei; Alkeskjold, Thomas Tanggaard; Bjarklev, Anders Overgaard


    SU-8 structures are built up to increase the fiber coupling efficiency of liquid crystal photonic bandgap fiber components. The resolution reduction of UV exposure is minimized to 4%, and insertion loss is reduced to 2.7dB.......SU-8 structures are built up to increase the fiber coupling efficiency of liquid crystal photonic bandgap fiber components. The resolution reduction of UV exposure is minimized to 4%, and insertion loss is reduced to 2.7dB....

  4. Handbook of display technology

    CERN Document Server

    Castellano, Joseph A


    This book presents a comprehensive review of technical and commercial aspects of display technology. It provides design engineers with the information needed to select proper technology for new products. The book focuses on flat, thin displays such as light-emitting diodes, plasma display panels, and liquid crystal displays, but it also includes material on cathode ray tubes. Displays include a large number of products from televisions, auto dashboards, radios, and household appliances, to gasoline pumps, heart monitors, microwave ovens, and more.For more information on display tech

  5. Slow-light-enhanced energy efficiency for the graphene microheater on silicon photonic crystal waveguides

    CERN Document Server

    Yan, Siqi; Frandsen, Lars Hagedorn; Xiao, Sanshui; Mortensen, N Asger; Dong, Jianji; Ding, Yunhong


    Slow light has been widely utilized to obtain enhanced nonlinearities, enhanced spontaneous emissions, and increased phase shifts owing to its ability to promote light-matter interactions. By incorporating a graphene microheater on a slow-light silicon photonic crystal waveguide, we experimentally demonstrated an energy-efficient graphene microheater with a tuning efficiency of 1.07 nm/mW and power consumption per free spectral range of 3.99 mW. The rise and decay times (10% to 90%) were only 750 ns and 525 ns, which, to the best of our knowledge, are the fastest reported response times for microheaters in silicon photonics. The corresponding record-low figure of merit of the device was 2.543 nW.s, which is one order of magnitude lower than results reported in previous studies. The influences of the graphene-photonic crystal waveguide interaction length and the shape of the graphene heater were also investigated, providing valuable guidelines for enhancing the graphene microheater tuning efficiency.

  6. A comparison of the suitability of cathode ray tube (CRT) and liquid crystal display (LCD) monitors as visual stimulators in mfERG diagnostics. (United States)

    Kaltwasser, Christoph; Horn, Folkert K; Kremers, Jan; Juenemann, Anselm


    The aim of this study was to determine up to which extent the specific characteristics of cathode ray tube (CRT) and liquid crystal display (LCD) monitors influence the retinal biosignal when used as stimulators in ocular electrophysiology. In a conventional CRT monitor, each pixel lights up only for a duration of a few milliseconds during each frame. In contrast, liquid crystal displays are quasi-static, i.e. each pixel has a constant luminance during the whole length of the frame, but lights up only with a certain delay after the trigger. These different display characteristics may affect the mfERG signal. The temporal and spatial luminance distributions of a CRT and an LCD monitor were measured in white flashes. The total amount of emitted light was calculated by integration of the intensity versus time curves. By means of an mfERG recording system (RETIsystem, Roland Consult, Brandenburg, Germany) first-order kernel (FOK) mfERG signals were computed and then analysed using customized MATLAB (TheMathWorks, Natick, MA, USA) software. With the two stimulator monitors, differences in the mfERG signal were observed. The latencies of mfERG responses recorded with the LCD monitor were significantly increased by 7.1 ms for N1 and 9.5 ms for P1 compared to the CRT. Due to a higher luminance, the N1 amplitude was significantly higher by approx. 2 dB in measurements with the LCD monitor while no significant difference could be detected with regard to the more contrast sensitive P1 amplitude. When using LCD monitors as stimulators the increase in latencies and differences in the luminance versus time profile must be taken into account. Prior to clinical application, the establishment of guidelines for the use of LCD monitors is recommended.

  7. [Evaluation of image quality using the normalized-rank approach for primary class liquid-crystal display (LCD) monitors with different colors and resolution]. (United States)

    Kuroki, Hidefumi; Katayama, Reiji; Sakaguchi, Taro; Maeda, Takashi; Morishita, Junji; Hayabuchi, Naofumi


    The purposes of this study were to evaluate the image quality of five types of liquid-crystal display (LCD) monitors by utilizing the normalized-rank approach and to investigate the effect of LCD monitor specifications, such as display colors, luminance, and resolution, on the evaluators' ranking. The LCD monitors used in this study were 2, 3 and 5 mega-pixel monochrome LCD monitors, and 2 and 3 mega-pixel color LCD monitors (Eizo Nanao Corporation). All LCD monitors were calibrated to the grayscale standard display function (GSDF) with different maximum luminance (recommended luminance) settings. Also, four kinds of radiographs were used for observer study based on the normalized-rank approach: three adult chest radiographs, three pediatric chest radiographs, three ankle joint radiographs, and four double-contrasted upper gastrointestinal radiographs. Ten radiological technologists participated in the observer study. Monochrome LCD monitors exhibited superior ranking with statistically significant differences (pLCD monitors in all kinds of radiographs. The major difference between monochrome and color monitors was luminance. Therefore, it is considered that the luminance of LCD monitors affects observers' evaluations based on image quality. Moreover, in the case of radiographs that include high frequency image components, the monitor resolution also affects the evaluation. In clinical practice, it is necessary to optimize the luminance and choose appropriate LCD monitors for diagnostic images.

  8. Determination of the Surface Plasmons Polaritons extraction efficiency from a self-assembled plasmonic crystal

    CERN Document Server

    Frederich, Hugo; Laverdant, Julien; de Marcillac, Willy Daney; Schwob, Catherine; Coolen, Laurent; Maître, Agnès


    We experimentally measure and analytically describe the fluorescence enhancement obtained by depositing CdSe/CdS nanocrystals onto a gold plasmonic crystal, a two-dimensional grating of macroscopic size obtained by gold deposition on a self-assembled opal. We show evidences of nanocrystals near-field coupling to the gold Surface Plasmons Polaritons (SPP) followed by grating-induced SPP re-emission to far-field. We develop a theoretical framework and an original method in order to evaluate, from photoluminescence experiments, the SPP extraction efficiency of a grating.

  9. Parameters for efficient growth of second harmonic field in nonlinear photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Shereena, E-mail:; Khan, Mohd. Shahid; Hafiz, Aurangzeb Khurram


    The ultrashort pulse propagation and nonlinear second harmonic generation under the undepleted pump approximation in a quadratic nonlinear photonic crystal (NPC) structure is theoretically investigated and the optimized parameters for high second harmonic generation conversion efficiency are extracted. The transfer matrix method is used for the numerical formulation for oblique angle of incidence. A unique set of material combination GaInP/InAlP is selected as alternating nonlinear and linear layers. The NPC parameters like incident angle and layer thickness are manipulated to obtain the exact phase matching using double resonance condition for a fixed number of layers with known experimental material parameters.

  10. An efficient optical biochemical sensor based on a polyatomic photonic crystal ring resonator (United States)

    Wang, Daobin; Liu, Yanjun; Yuan, Lihua; Lei, Jingli; Li, Xiaoxiao; wu, Gang; Hou, Shanglin


    In this paper, we introduce and investigate a design concept for a polyatomic photonic crystal ring resonator (PCRR). In contrast to conventional sensors, this PCRR comprises two different branching waveguides (WG), which are all oriented in the same lattice direction, but with different optical propagation properties due to the binary nature of the diatomic square lattice. Based on this new scheme, an on-chip biochemical sensor is proposed. Electromagnetic analysis, PWE and FDTD numerical techniques, were used to investigate the sensing performance. Our results show that such a sensor can efficiently detect small changes in the refractive index within the sensing area.

  11. Domain-Reversed Lithium Niobate Single-Crystal Fibers are Potentially for Efficient Terahertz Wave Generation

    Directory of Open Access Journals (Sweden)

    Kitt Reinhardt


    Full Text Available Nonlinear frequency conversion remains one of the dominant approaches to efficiently generate THz waves. Significant material absorption in the THz range is the main factor impeding the progress towards this direction. In this research, a new multicladding nonlinear fiber design was proposed to solve this problem, and as the major experimental effort, periodic domain structure was introduced into lithium niobate single-crystal fibers by electrical poling. The introduced periodic domain structures were nondestructively revealed using a crossly polarized optical microscope and a confocal scanning optical microscope for quality assurance.

  12. Application of Bent Crystals at IHEP 70-GeV Accelerator to Enhance the Efficiency of its Usage

    CERN Document Server

    Afonin, A G; Chesnokov, Yu A; Fedotov, Yu S; Galjaev, A N; Gres, V N; Ivanov, Yu B; Kotov, V I; Maisheev, V A; Medvedev, V A; Minchenko, A V; Scandale, Walter; Terekhov, V I; Troyanov, E F; Zapolskii, V N; Zelenov, B A


    Bent crystal was extracting 70-GeV protons with average intensity 4x10$^{11}$ (as measured in external beamline) per spill of ~1.6 s duration, in parallel to the simultaneous work of two internal targets in the accelerator ring. An additional crystal, placed in the external beamline, was deflecting a small part of the extracted beam with intensity ~10$^7$ protons toward another physics experiment. Crystal-extracted beam had a typical size of 4 mm by 4 mm fwhm at the end of the external beamline. Measurements for the extraction efficiency and other characteristics at the simultaneous work of four experimental set-ups are presented. With crystal working in the above-said regime during one month, no degradation of channeling was observed. The studies of extraction efficiency have been continued with new crystals.

  13. An efficient method for variable region assembly in the construction of scFv phage display libraries using independent strand amplification. (United States)

    Sotelo, Pablo; Collazo, Noberto; Zuñiga, Roberto; Gutiérrez-González, Matías; Catalán, Diego; Ribeiro, Carolina Hager; Aguillón, Juan Carlos; Molina, María Carmen


    Phage display library technology is a common method to produce human antibodies. In this technique, the immunoglobulin variable regions are displayed in a bacteriophage in a way that each filamentous virus displays the product of a single antibody gene on its surface. From the collection of different phages, it is possible to isolate the virus that recognizes specific targets. The most common form in which to display antibody variable regions in the phage is the single chain variable fragment format (scFv), which requires assembly of the heavy and light immunoglobulin variable regions in a single gene. In this work, we describe a simple and efficient method for the assembly of immunoglobulin heavy and light chain variable regions in a scFv format. This procedure involves a two-step reaction: (1) DNA amplification to produce the single strand form of the heavy or light chain gene required for the fusion; and (2) mixture of both single strand products followed by an assembly reaction to construct a complete scFv gene. Using this method, we produced 6-fold more scFv encoding DNA than the commonly used splicing by overlap extension PCR (SOE-PCR) approach. The scFv gene produced by this method also proved to be efficient in generating a diverse scFv phage display library. From this scFv library, we obtained phages that bound several non-related antigens, including recombinant proteins and rotavirus particles.

  14. Synergy of ammonium chloride and moisture on perovskite crystallization for efficient printable mesoscopic solar cells (United States)

    Rong, Yaoguang; Hou, Xiaomeng; Hu, Yue; Mei, Anyi; Liu, Linfeng; Wang, Ping; Han, Hongwei


    Organometal lead halide perovskites have been widely used as the light harvester for high-performance solar cells. However, typical perovskites of methylammonium lead halides (CH3NH3PbX3, X=Cl, Br, I) are usually sensitive to moisture in ambient air, and thus require an inert atmosphere to process. Here we demonstrate a moisture-induced transformation of perovskite crystals in a triple-layer scaffold of TiO2/ZrO2/Carbon to fabricate printable mesoscopic solar cells. An additive of ammonium chloride (NH4Cl) is employed to assist the crystallization of perovskite, wherein the formation and transition of intermediate CH3NH3X·NH4PbX3(H2O)2 (X=I or Cl) enables high-quality perovskite CH3NH3PbI3 crystals with preferential growth orientation. Correspondingly, the intrinsic perovskite devices based on CH3NH3PbI3 achieve an efficiency of 15.6% and a lifetime of over 130 days in ambient condition with 30% relative humidity. This ambient-processed printable perovskite solar cell provides a promising prospect for mass production, and will promote the development of perovskite-based photovoltaics. PMID:28240286

  15. Increasing the lasing efficiency in cholesteric liquid-crystal photonic structures

    Energy Technology Data Exchange (ETDEWEB)

    Palto, S. P., E-mail:; Shtykov, N. M.; Barnik, M. I.; Umanskii, B. A. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)


    Two types of lasing in cholesteric liquid crystals (LCs) in the range of luminescence of laser dye molecules have been investigated. The first type belongs to the Bragg modes at the photonic band edge, which propagate along the normal to the LC layer. The second type of lasing is related to the modes leaking into the substrate and propagating at small angles to the LC layer. It is shown that the Bragg lasing efficiency can be significantly increased under wide-aperture optical pumping. The method proposed for increasing the lasing efficiency is based on suppressing the excitation of leaky laser modes using partially absorbing thin films as the coatings for LC-orienting substrates. Both experimental results and the theoretical model of the effect using the numerical simulation data are discussed.

  16. Simple down conversion nano-crystal coatings for enhancing Silicon-solar cells efficiency

    Directory of Open Access Journals (Sweden)

    Gur Mittelman


    Full Text Available Utilizing self-assembled nano-structured coatings on top of existing solar cells has thepotential to increase the total quantum efficiency of the cell using a simple and cheap process. In ourwork we have exploited the controlled absorption of nano-crystal with different band gaps to realizedown conversion artificial antennas that self-assembled on the device surface. The UV sun light isconverted to the visible light enhancing the solar cell performance in two complementary routes; a.protecting the solar cell and coatings from the UV illumination and therefore reducing the UVradiation damage. b. enhancing the total external quantum efficiency of the cell by one percent. Thisis achieved using a simple cheap process that can be adjusted to many different solar cells.

  17. Power Efficient Design of DisplayPort (7.0) Using Low-voltage differential signaling IO Standard Via UltraScale Field Programming Gate Arrays

    DEFF Research Database (Denmark)

    Das, Bhagwan; Abdullah, M.F.L.; Hussain, Dil muhammed Akbar


    Port (7.0) need be reduced. In this paper, a power efficient design for DisplayPort (7.0) is proposed using LVDS IO Standard. The proposed design is tested for different frequencies; 500 MHz, 700 MHz, 1.0 GHz, and 1.6 GHz. The design is implemented using vhdl in UltraScale FPGA. It is determined...... the designed vhdl based design of DisplayPort (7.0) can reduced 92% using LVDS IO Standard for all frequencies; 500 MHz, 700 MHz, 1.0 GHz, and 1.6 GHz, compared to vhdl based design of DisplayPort (7.0) without using IO Standard. The proposed design of vhdl based design of DisplayPort (7.0) using LVDS IO...... Standard offers no power consumption for DisplayPort (7.0) in standby mode. The vhdl based design of DisplayPort (7.0) using LVDS IO Standard will be helpful to process the high resolution video at low power consumption...

  18. A laboratory investigation into the aggregation efficiency of small ice crystals

    Directory of Open Access Journals (Sweden)

    P. J. Connolly


    Full Text Available The aggregation of ice crystals and its temperature dependence is studied in the laboratory using a large ice cloud chamber. This process is important to the evolution of ice clouds in earth's atmosphere, yet there have been relatively few laboratory studies quantifying this parameter and its dependence on temperature. A detailed microphysical model is used to interpret the results from the experiments and derive best estimates for the aggregation efficiency as well as error bars. Our best estimates for the aggregation efficiency, at temperatures other than −15 °C, (in the interval −30≤T≤5 °C are mostly in agreement with previous findings, which were derived using a very different approach to that described here. While the errors associated with such experiments are reasonably large, statistically, at temperatures other than −15, we are able to rule out aggregation efficiencies larger than 0.5 at the 75th percentile and rule out non-zero values at −15 °C, whereas at −15 °C we can rule out values higher than 0.85 and values lower than 0.35. The values of the aggregation efficiency shown here may be used in model studies of aggregation, but care must be taken that they only apply for the initial stages of aggregate growth, with humidities at or close to water saturation, and for particles up to a maximum size of ~500 μm. They may therefore find useful application for modelling supercooled mid-level layer clouds that contain ice crystals, which are known to be important radiatively.

  19. Real-time synchronized rendering of multi-view video for 8Kx4K three-dimensional display with spliced four liquid crystal panels (United States)

    Cui, Huilong; Sang, Xinzhu; Xing, Shujun; Ning, Jiwei; Yan, Binbin; Dou, Wenhua; Xiao, Liquan


    A high speed synchronized rendering of multi-view video for 8K×4K multi-LCD-spliced three-dimensional (3D) display system based on CUDA is demonstrated. Because the conventional image processing calculation method is no longer applicable to this 3D display system, the CUDA technology is used for 3D image processing to address the problem of low efficiency.The 8K×4K screen is composed of four LCD screens, and accurate segmentation of the scene is carried out to ensure the correct display of 3D contents and a set of controlling and the host software are optimally implemented to make all of the connected processors render 3D videos simultaneously. The system which is based on the master-slave synchronization communication mode and DIBR-CUDA accelerated algorithm is used to realize the high resolution, high frame rate, large size, and wide view angle video rendering for the real-time 3D display. Experimental result shows a stable frame-rate at 30 frame-per-second and the friendly interactive interface can be achieved.

  20. Self-assembled hierarchical nanostructures for high-efficiency porous photonic crystals. (United States)

    Passoni, Luca; Criante, Luigino; Fumagalli, Francesco; Scotognella, Francesco; Lanzani, Guglielmo; Di Fonzo, Fabio


    The nanoscale modulation of material properties such as porosity and morphology is used in the natural world to mold the flow of light and to obtain structural colors. The ability to mimic these strategies while adding technological functionality has the potential to open up a broad array of applications. Porous photonic crystals are one such technological candidate, but have typically underachieved in terms of available materials, structural and optical quality, compatibility with different substrates (e.g., silicon, flexible organics), and scalability. We report here an alternative fabrication method based on the bottom-up self-assembly of elementary building blocks from the gas phase into high surface area photonic hierarchical nanostructures at room temperature. Periodic refractive index modulation is achieved by stacking layers with different nanoarchitectures. High-efficiency porous Bragg reflectors are successfully fabricated with sub-micrometer thick films on glass, silicon, and flexible substrates. High diffraction efficiency broadband mirrors (R≈1), opto-fluidic switches, and arrays of photonic crystal pixels with sizesolar cells, and photocatalysis are envisioned.

  1. Near-unity coupling efficiency of a quantum emitter to a photonic crystal waveguide. (United States)

    Arcari, M; Söllner, I; Javadi, A; Lindskov Hansen, S; Mahmoodian, S; Liu, J; Thyrrestrup, H; Lee, E H; Song, J D; Stobbe, S; Lodahl, P


    A quantum emitter efficiently coupled to a nanophotonic waveguide constitutes a promising system for the realization of single-photon transistors, quantum-logic gates based on giant single-photon nonlinearities, and high bit-rate deterministic single-photon sources. The key figure of merit for such devices is the β factor, which is the probability for an emitted single photon to be channeled into a desired waveguide mode. We report on the experimental achievement of β=98.43%±0.04% for a quantum dot coupled to a photonic crystal waveguide, corresponding to a single-emitter cooperativity of η=62.7±1.5. This constitutes a nearly ideal photon-matter interface where the quantum dot acts effectively as a 1D "artificial" atom, since it interacts almost exclusively with just a single propagating optical mode. The β factor is found to be remarkably robust to variations in position and emission wavelength of the quantum dots. Our work demonstrates the extraordinary potential of photonic crystal waveguides for highly efficient single-photon generation and on-chip photon-photon interaction.

  2. Highly efficient four wave mixing in GaInP photonic crystal waveguides. (United States)

    Eckhouse, V; Cestier, I; Eisenstein, G; Combrié, S; Colman, P; De Rossi, A; Santagiustina, M; Someda, C G; Vadalà, G


    We report highly efficient four wave mixing in a GaInP photonic crystal waveguide. Owing to its large bandgap, the ultrafast Kerr nonlinearity of GaInP is not diminished by two photon absorption and related carrier effects for photons in the 1550 nm range. A four-wave-mixing efficiency of -49 dB was demonstrated for cw pump and probe signals in the milliwatt range, while for pulsed pumps with a peak power of 25 mW the conversion efficiency increased to -36 dB. Measured conversion efficiency dependencies on pump probe detuning and on pump power are in excellent agreement with a simple analytical model from which the nonlinear parameter gamma is extracted. Gamma scales approximately with the square of the slow down factor and varies from 800 W(-1) m(-1) at a pump wavelength lambda(p)=1532 nm to 2900 W(-1) m(-1) at lambda(p)=1550 nm. These values are consistent with those obtained from self phase modulation experiments in similar devices.

  3. Slow-light-enhanced energy efficiency for graphene microheaters on silicon photonic crystal waveguides (United States)

    Yan, Siqi; Zhu, Xiaolong; Frandsen, Lars Hagedorn; Xiao, Sanshui; Mortensen, N. Asger; Dong, Jianji; Ding, Yunhong


    Slow light has been widely utilized to obtain enhanced nonlinearities, enhanced spontaneous emissions and increased phase shifts owing to its ability to promote light-matter interactions. By incorporating a graphene on a slow-light silicon photonic crystal waveguide, here we experimentally demonstrate an energy-efficient graphene microheater with a tuning efficiency of 1.07 nmmW-1 and power consumption per free spectral range of 3.99 mW. The rise and decay times (10-90%) are only 750 and 525 ns, which, to the best of our knowledge, are the fastest reported response times for microheaters in silicon photonics. The corresponding figure of merit of the device is 2.543 nW s, one order of magnitude better than results reported in previous studies. The influence of the length and shape of the graphene heater to the tuning efficiency is further investigated, providing valuable guidelines for enhancing the tuning efficiency of the graphene microheater.

  4. Slow-light-enhanced energy efficiency for graphene microheaters on silicon photonic crystal waveguides (United States)

    Yan, Siqi; Zhu, Xiaolong; Frandsen, Lars Hagedorn; Xiao, Sanshui; Mortensen, N. Asger; Dong, Jianji; Ding, Yunhong


    Slow light has been widely utilized to obtain enhanced nonlinearities, enhanced spontaneous emissions and increased phase shifts owing to its ability to promote light–matter interactions. By incorporating a graphene on a slow-light silicon photonic crystal waveguide, here we experimentally demonstrate an energy-efficient graphene microheater with a tuning efficiency of 1.07 nmmW−1 and power consumption per free spectral range of 3.99 mW. The rise and decay times (10–90%) are only 750 and 525 ns, which, to the best of our knowledge, are the fastest reported response times for microheaters in silicon photonics. The corresponding figure of merit of the device is 2.543 nW s, one order of magnitude better than results reported in previous studies. The influence of the length and shape of the graphene heater to the tuning efficiency is further investigated, providing valuable guidelines for enhancing the tuning efficiency of the graphene microheater. PMID:28181531

  5. High-efficiency deflection of high energy protons due to channeling along the axis of a bent silicon crystal (United States)

    Scandale, W.; Arduini, G.; Butcher, M.; Cerutti, F.; Garattini, M.; Gilardoni, S.; Lechner, A.; Masi, A.; Mirarchi, D.; Montesano, S.; Redaelli, S.; Rossi, R.; Smirnov, G.; Breton, D.; Burmistrov, L.; Chaumat, V.; Dubos, S.; Maalmi, J.; Puill, V.; Stocchi, A.; Bagli, E.; Bandiera, L.; Germogli, G.; Guidi, V.; Mazzolari, A.; Dabagov, S.; Murtas, F.; Addesa, F.; Cavoto, G.; Iacoangeli, F.; Galluccio, F.; Afonin, A. G.; Chesnokov, Yu. A.; Durum, A. A.; Maisheev, V. A.; Sandomirskiy, Yu. E.; Yanovich, A. A.; Kovalenko, A. D.; Taratin, A. M.; Denisov, A. S.; Gavrikov, Yu. A.; Ivanov, Yu. M.; Lapina, L. P.; Malyarenko, L. G.; Skorobogatov, V. V.; James, T.; Hall, G.; Pesaresi, M.; Raymond, M.


    A deflection efficiency of about 61% was observed for 400 GeV/c protons due to channeling, most strongly along the axis of a bent silicon crystal. It is comparable with the deflection efficiency in planar channeling and considerably larger than in the case of the axis. The measured probability of inelastic nuclear interactions of protons in channeling along the axis is only about 10% of its amorphous level whereas in channeling along the (110) planes it is about 25%. High efficiency deflection and small beam losses make this axial orientation of a silicon crystal a useful tool for the beam steering of high energy charged particles.

  6. An efficient methodology for assessing attention to and effect of nutrition information displayed front-of-pack

    NARCIS (Netherlands)

    Bialkova, S.E.; Trijp, van H.C.M.


    A methodology for assessing attention to and effect of nutrition information displayed front-of-pack is presented. The methodology is based on an integration of the visual search paradigm, the choice paradigm and eye-tracking measures, and moves beyond reliance on self-report measures for attention

  7. A FPGA-Based Integrated Controller for Liquid Crystal Display%基于FPGA的液晶控制器设计

    Institute of Scientific and Technical Information of China (English)

    汪金辉; 张健; 宫娜; 吴武臣; 董利民


    介绍了一种基于 FPGA 的集成液晶控制器.系统由显示模块和控制模块组成,显示模块(LEM101)为10 bit 多功能通用型器件,内含看门狗(WDT)/时钟发生器,2 种频率的蜂鸣驱动电路,内置显示RAM,及3-4线串行接口.控制器基于1.5万门 FPGA 芯片(Xilinx XC3S1500),易于扩展和升级.利用 Verilog 语言,在 FPGA 芯片中实现了控制模块的设计,通过 GR-XC3S-1500 开发板验证,本设计完全满足对液晶模块的控制要求,并成功应用于光栅测量显示控制系统中.控制模块由四部分组成:存储、译码、串并转换器、输出控制.文章讨论了设计方法和设计过程,给出了部分 Verilog 代码.此外,本设计还创造性地在电源和 FPGA 芯片间插入低成本元件,满足了液晶上电后,初始化命令的延迟要求,从而节约了 FPGA 的硬件资源.%This paper presents a FPGA-based integrated controller for liquid crystal display system. The system consists of a display module and a controlling module. The former (LCM101 chip) is 10 bit multi-functional device with a WDT(watch dog timer), a dual frequency driving circuit, a display RAM and seri-al interface. The later is an integrated display controller using a FPGA chip of 1. 5million gate (Xilinx XC3S1500), so being easy to extend and upgrade. Integrated controller design in FPGA chip has been im-plemented by using Verilog language coding and verified in Xilinx Development Board. The design fits the requirements to control liquid crystal display entirely, and is successfully applied in a grating measurement system. The controller module includes four parts: storage, decoding, serial-parallel interface translation,and output controlling. This paper discusses the design method and the design process of each part above,providing Verilog codes partly. What's more a low-cost accessory is originally located between FPGA chip and power supply in hardware design to satisfy delay after liquid crystal electrify

  8. Effect of spatial noise of medical grade Liquid Crystal Displays (LCD) on the detection of micro-calcification (United States)

    Roehrig, Hans; Fan, Jiahua; Dallas, William J.; Krupinski, Elizabeth A.; Johnson, Jeffrey


    This presentation describes work in progress that is the result of an NIH SBIR Phase 1 project that addresses the wide- spread concern for the large number of breast-cancers and cancer victims [1,2]. The primary goal of the project is to increase the detection rate of microcalcifications as a result of the decrease of spatial noise of the LCDs used to display the mammograms [3,4]. Noise reduction is to be accomplished with the aid of a high performance CCD camera and subsequent application of local-mean equalization and error diffusion [5,6]. A second goal of the project is the actual detection of breast cancer. Contrary to the approach to mammography, where the mammograms typically have a pixel matrix of approximately 1900 x 2300 pixels, otherwise known as FFDM or Full-Field Digital Mammograms, we will only use sections of mammograms with a pixel matrix of 256 x 256 pixels. This is because at this time, reduction of spatial noise on an LCD can only be done on relatively small areas like 256 x 256 pixels. In addition, judging the efficacy for detection of breast cancer will be done using two methods: One is a conventional ROC study [7], the other is a vision model developed over several years starting at the Sarnoff Research Center and continuing at the Siemens Corporate Research in Princeton NJ [8].

  9. Photonic crystal coupled TiO(2)/polymer hybrid for efficient photocatalysis under visible light irradiation. (United States)

    Liao, Gaozu; Chen, Shuo; Quan, Xie; Chen, Huan; Zhang, Yaobin


    Inverse TiO(2) opal photonic crystal coupled TiO(2)/poly(3-hexylthiophene) (bilayer TiO(2)/P3HT) was structured on FTO substrate for efficient photocatalysis under visible light irradiation (lambda > 400 nm). We expected that the photocatalytic capability of this hybrid photocatalyst could be enhanced by the efficient visible light absorption owing to the photonic crystal structure and effective charge separation owing to the unique heterojunction built between TiO(2) and P3HT. The bilayer TiO(2)/P3HT photocatalyst was prepared first by depositing inverse TiO(2) opal on FTO substrate via replicating polystyrene opal, followed by spin coating a layer of TiO(2) nanoparticles on the inverse TiO(2) opal. The as prepared bilayer TiO(2) was modified by P3HT via dipping method. Environmental scanning electron microscopy (ESEM) images demonstrated that the as prepared photocatalyst was composed of inverse TiO(2) opal layer and TiO(2) nanoparticles layer. The UV-vis diffuse reflectance spectra showed that the optical absorption for bilayer TiO(2)/P3HT was more intensive than for pristine TiO(2) nanoparticle/P3HT (NP-TiO(2)/P3HT) in the range of 400-650 nm. The enhanced generation of photocurrent under visible light irradiation (lambda > 400 nm) was observed using the bilayer TiO(2)/P3HT. The results of photocatalytic experiments under visible light irradiation revealed that the pseudofirst-order kinetic constant of photocatalytic degradation of methylene blue using the bilayer TiO(2)/P3HT was 2.08 times as great as that using NP-TiO(2)/P3HT, showing the advantage of the unique structure in the bilayer TiO(2)/P3HT for efficient photocatalysis.

  10. Vortex beam generation and other advanced optics experiments reproduced with a twisted-nematic liquid-crystal display with limited phase modulation (United States)

    Cofré, Aaron; García-Martínez, Pascuala; Vargas, Asticio; Moreno, Ignacio


    In this work we propose the use of twisted-nematic liquid-crystal spatial light modulators (TN-LC-SLM) as a useful tool for training students in the manipulation of light beams with phase-only masks. In particular, we focus the work on the realization of phase-only gratings and phase-only spiral phases for the generation of vortex beams, beams carrying orbital angular momentum (OAM). Despite the extensive activity in this field, its experimental implementation for educational purposes is limited because it requires the use of very expensive high-resolution liquid-crystal on silicon (LCOS) SLMs. Here, we show that a low-cost experimental implementation can be done with older TNLC technology. However, these devices, intended for display applications, exhibit rather limited optical phase modulation properties in comparison with modern LCOS devices, such as a very low range of phase modulation and a general coupled intensity modulation. However, we show that a precise characterization of their retardance parameters permits their operation in useful modulation configurations. As examples, we include one continuous phase-only configuration useful for reproducing the optimal triplicator phase grating, and a binary π-phase modulation. We include experiments with the realization of different phase diffraction gratings, and their combination with spiral phase patterns and lens functions to generate a variety of vortex beams.

  11. Review of organic light-emitting diodes with thermally activated delayed fluorescence emitters for energy-efficient sustainable light sources and displays (United States)

    Volz, Daniel


    Thermally activated delayed fluorescence (TADF) is an emerging hot topic. Even though this photophysical mechanism itself has been described more than 50 years ago and optoelectronic devices with organic matter have been studied, improved, and even commercialized for decades now, the realization of the potential of TADF organic light-emitting diodes (OLEDs) happened only recently. TADF has been proven to be an attractive and very efficient alternative for phosphorescent materials, such as dopants in OLEDs, light-emitting electrochemical cells as well as potent emitters for chemiluminescence. In this review, the TADF concept is introduced in terms that are also understandable for nonchemists. The basic concepts behind this mechanism as well as state-of-the-art examples are discussed. In addition, the future economic impact, especially for the lighting and display market, is addressed here. We conclude that TADF materials are especially helpful to realize efficient, durable deep blue and white displays.

  12. OLED displays and lighting

    CERN Document Server

    Koden, Mitsuhiro


    Organic light-emitting diodes (OLEDs) have emerged as the leading technology for the new display and lighting market. OLEDs are solid-state devices composed of thin films of organic molecules that create light with the application of electricity. OLEDs can provide brighter, crisper displays on electronic devices and use less power than conventional light-emitting diodes (LEDs) or liquid crystal displays (LCDs) used today. This book covers both the fundamentals and practical applications of flat and flexible OLEDs.

  13. The influence of liquid crystal display monitors on observer performance for the detection of interstitial lung markings on both storage phosphor and flat-panel-detector chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Yon Mi [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-dong, Kangnam-ku, Seoul 135-710 (Korea, Republic of); Department of Radiology, Gachon University Gil Hospital, 1198, Guwol-dong, Namdong-gu, Incheon 405-760 (Korea, Republic of); Chung, Myung Jin [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-dong, Kangnam-ku, Seoul 135-710 (Korea, Republic of)], E-mail:; Lee, Kyung Soo [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-dong, Kangnam-ku, Seoul 135-710 (Korea, Republic of); Choe, Bong-Keun [Department of Preventive Medicine, School of Medicine, Kyunghee University, Seoul (Korea, Republic of)


    Purpose: To compare observer performance with a flat-panel liquid crystal display (LCD) monitor and with a high-resolution gray-scale cathode ray tube (CRT) monitor in the detection of interstitial lung markings using a silicon flat-panel-detector direct radiography (DR) and storage phosphor computed radiography (CR) in a clinical setting. Materials and methods: We displayed 39 sets of posteroanterior chest radiographs from the patients who were suspected of interstitial lung disease. Each sets consisted of DR, CR and thin-section CT as the reference standard. Image identities were masked, randomly sorted, and displayed on both five mega pixel (2048 x 2560 x 8 bits) LCD and CRT monitors. Ten radiologists independently rated their confidence in detection for the presence of linear opacities in the four fields of the lungs; right upper, left upper, right lower, and left lower quadrant. Performance of a total 6240 (39 sets x 2 detector systems x 2 monitor system x 4 fields x 10 observers) observations was analyzed by multi-reader multi-case receiver operating characteristic (ROC) analysis. Differences between monitor systems in combinations of detector systems were compared using ANOVA and paired-samples t-test. Results: Area under curves (AUC) for the presence of linear opacities measured by ROC analysis was higher on the LCDs than CRTs without statistical significance (p = 0.082). AUC was significantly higher on the DR systems than CR systems (p = 0.006). AUC was significantly higher on the LCDs than CRTs for DR systems (p = 0.039) but not different for CR systems (p = 0.301). Conclusion: In clinical conditions, performance of the LCD monitor appears to be better for detecting interstitial lung markings when interfaced with DR systems.

  14. Silicon nanocrystal-based photonic crystal slabs with broadband and efficient directional light emission. (United States)

    Ondič, L; Varga, M; Pelant, I; Valenta, J; Kromka, A; Elliman, R G


    Light extraction from a thin planar layer can be increased by introducing a two-dimensional periodic pattern on its surface. This structure, the so-called photonic crystal (PhC) slab, then not only enhances the extraction efficiency of light but can direct the extracted emission into desired angles. Careful design of the structures is important in order to have a spectral overlap of the emission with extraction (leaky) modes. We show that by fabricating PhC slabs with optimized dimensions from silicon nanocrystals (SiNCs) active layers, the extraction efficiency of vertical light emission from SiNCs at a particular wavelength can be enhanced ∼ 11 times compared to that of uncorrugated SiNCs-rich layer. More importantly, increased light emission can be obtained in a broad spectral range and, simultaneously, the extracted light can stay confined within relatively narrow angle around the normal to the sample plane. We demonstrate experimentally and theoretically that the physical origin of the enhancement is such that light originating from SiNCs first couples to leaky modes of the PhCs and is then efficiently extracted into the surrounding.

  15. Synthesis, growth and optical properties of an efficient nonlinear optical single crystal: L-alanine DL-malic acid (United States)

    Kirubagaran, R.; Madhavan, J.


    Single crystals of L-alanine DL-malic acid (LADLMA) have been grown from aqueous solution by slow-cooling technique. Powder X-ray diffraction studies reveal the structure of the crystal to be orthorhombic. The nonlinear optical conversion efficiency test was carried out for the grown crystals using the Kurtz powder technique. The third order nonlinear refractive index and the nonlinear absorption coefficient where evaluated by Z-scan measurements. As the material have a negative refractive index it could be used in the protection of optical sensors such as night vision devices.

  16. Tuning the dielectric properties of thiourea analog crystals for efficient nonlinear optical applications

    Energy Technology Data Exchange (ETDEWEB)

    Sabari Girisun, T.C. [Department of Physics, Bishop Heber College, Tiruchirappalli 620 017, Tamil Nadu (India); School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu (India); Dhanuskodi, S., E-mail: [School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu (India)


    Materials with low dielectric constant have attracted a great deal of interest in the field of nonlinear applications and microelectronic industry. Metal complexes of thiourea with group II transition metals (Zn, Cd) as central atom and period III elements (S, Cl) were synthesized by chemical reaction method and single crystals were grown from aqueous solution by slow evaporation method. By parallel plate capacitor technique, the dielectric response, dissipation factor, ac conductivity and impedance of virgin and metal complexes have been studied in the frequency (100 Hz to 5 MHz) and temperature (303-423 K) ranges. Metal complexes of thiourea with cadmium substitute have a low dielectric constant less than 10. Also the presence of chlorine in the metal complex induces noncentro symmetric structure. Hence the role of group II transition metals and period III elements in tuning the dielectric properties for efficient nonlinear applications has been studied.

  17. Thermal, FT–IR and SHG efficiency studies of L-arginine doped KDP crystals

    Indian Academy of Sciences (India)

    K D Parikh; D J Dave; B B Parekh; M J Joshi


    Potassium dihydrogen phosphate (KDP) is a well known nonlinear optical (NLO) material with different applications. Since most of the amino acids exhibit NLO property, it is of interest to dope them in KDP. In the present study, amino acid L-arginine was doped in KDP. The doping of L-arginine was confirmed by FT–IR and paper chromatography. Thermogravimetry suggested that as the amount of doping increases the thermal stability decreases as well as the value of thermodynamic and kinetic parameters decreases. The second harmonic generation (SHG) efficiency of L-arginine doped KDP crystals was found to be increasing with doping concentration of L-arginine. The results are discussed here.

  18. Efficient single photon emission from a high-purity hexagonal boron nitride crystal (United States)

    Martínez, L. J.; Pelini, T.; Waselowski, V.; Maze, J. R.; Gil, B.; Cassabois, G.; Jacques, V.


    Among a variety of layered materials used as building blocks in van der Waals heterostructures, hexagonal boron nitride (hBN) appears as an ideal platform for hosting optically active defects owing to its large band gap (˜6 eV ). Here we study the optical response of a high-purity hBN crystal under green laser illumination. By means of photon correlation measurements, we identify individual defects emitting a highly photostable fluorescence under ambient conditions. A detailed analysis of the photophysical properties reveals a high quantum efficiency of the radiative transition, leading to a single photon source with very high brightness (˜4 ×106 counts s-1). These results illustrate how the wide range of applications offered by hBN could be further extended to photonic-based quantum information science and metrology.

  19. Efficient generation of broad Raman sidebands in an index-guided photonic crystal fiber. (United States)

    Li, Ying; Hou, Jing; Jiang, Zongfu; Leng, Jinyong


    The efficient generation of broad Raman sidebands is experimentally demonstrated in a short piece of index-guided photonic crystal fiber, which is pumped by a high-peak-power pulse near the zero-dispersion wavelength and seeded by a continuous-wave Stokes signal centered at 1117 nm. The Raman sidebands generated via stimulated Raman scattering and cascaded four-wave mixing contain five Stokes and six anti-Stokes peaks and span from 827 to 1398 nm, and the 3 dB linewidth for each peak is smaller than 1 nm. However, the pure Raman sidebands are largely dependent on the pulse pump power as well as the fiber length.

  20. High efficiency terahertz-wave photonic crystal fiber optical parametric oscillator. (United States)

    Li, Shaopeng; Liu, Hongjun; Huang, Nan; Sun, Qibing; Li, Xuefeng


    We theoretically propose phase matched terahertz (THz)-wave generation via degenerate four-wave mixing (FWM) in a fiber optical parametric oscillator (FOPO) with our newly designed photonic crystal fiber (PCF). Perfect phase matching is realized when we locate the pump wavelength in the normal group-velocity dispersion (GVD) regime. The generated THz-wave can be tuned from 4.7578 to 5.9015 THz by varying the pump wavelength. Moreover, peak power of 27.38 W at 5.9015 THz with conversion efficiency of 1.37% is realized when the pump peak power of 2000 W is at 4.675 μm in our FOPO.

  1. A computationally efficient method to solve the Takagi-Taupin equations for a large deformed crystal

    CERN Document Server

    Honkanen, Ari-Pekka; Huotari, Simo


    We present a treatise on solving the Takagi-Taupin equations in the case of a strain field with an additional, spatially slowly varying component (owing to \\emph{e.g.}~heat expansion or angular compression). We show that the presence of such a component in a typical case merely shifts the reflectivity curve as a function of wavelength or incidence angle, while having a negligible effect on its shape. On the basis of the derived result, we develop a computationally efficient method to calculate the reflectivity curve of a large deformed crystal. The validity of the method is demonstrated by compared computed reflectivity curves with experimental ones for bent silicon wafers. An excellent agreement is observed.

  2. High Efficiency Single Crystal CdTe Solar Cells: November 19, 2009 - January 31, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Carmody, M.; Gilmore, A.


    The goal of the program was to develop single crystal CdTe-based top cells grown on Si solar cells as a platform for the subsequent manufacture of high efficiency tandem cells for CPV applications. The keys to both the single junction and the tandem junction cell architectures are the ability to grow high quality single-crystal CdTe and CdZnTe layers on p-type Si substrates, to dope the CdTe and CdZnTe controllably, both n and p-type, and to make low resistance ohmic front and back contacts. EPIR demonstrated the consistent MBE growth of CdTe/Si and CdZnTe/Si having high crystalline quality despite very large lattice mismatches; epitaxial CdTe/Si and CdZnTe/Si consistently showed state-of-the-art electron mobilities and good hole mobilities; bulk minority carrier recombination lifetimes of unintentionally p-doped CdTe and CdZnTe grown by MBE on Si were demonstrated to be consistently of order 100 ns or longer; desired n- and p-doping levels were achieved; solar cell series specific resistances <10 ?-cm2 were achieved; A single-junction solar cell having a state-of-the-art value of Voc and a unverified 16.4% efficiency was fabricated from CdZnTe having a 1.80 eV bandgap, ideal for the top junction in a tandem cell with a Si bottom junction.

  3. A novel peptide, selected from phage display library of random peptides, can efficiently target into human breast cancer cell

    Institute of Scientific and Technical Information of China (English)

    DONG Jian; LIU WeiQing; JIANG AiMei; ZHANG KeJian; CHEN MingQing


    To develop a targeting vector for breast cancer biotherapy, MDA-MB-231 cell, a human breast cancer cell line, was co-cultured with pC89 (9 aa) phage display library of random peptides. In multiple inde-pendent peptide-presenting phage screening trials, subtilisin was used as a protease to inactivate ex-tra-cellular phages. The internalized phages were collected by cell lysising and amplified in E. coli XLI-Blue. Through five rounds of selection, the peptide-presenting phages which could be internalized in MDA-MB-231 cells were isolated. A comparison was made between internalization capacities of pep-tide-presenting phages isolated from MDA-MB-231 cells and RGD-integrin binding phage by cocultur-ing them with other human tumor cell lines and normal cells. The nucleotide sequences of isolated peptide-presenting phages were then determined by DNA sequencing. To uncover whether phage coat protein or amino acid order was required for the character of the peptide to MDA-MB-231 cells, three peptides were synthesized. They are CASPSGALRSC, ASPSGALRS and CGVIFDHSVPC (the shifted sequence of CASPSGALRSC), and after coculturing them with different cell lines, their targeting ca-pacities to MDA-MB-231 cells were detected. These data suggested that the internalization process was highly selective, and capable of capturing a specific peptide from parent peptide variants. Moreover, the targeting internalization event of peptides was an amino acid sequence dependent manner. The results demonstrated the feasibility of using phage display library of random peptides to develop new targeting system for intracellular delivery of macromolecules, and the peptide we obtained might be modified as a targeting vector for breast cancer gene therapy.

  4. Comparison and characterization of efficient frequency doubling at 397.5 nm with PPKTP, LBO and BiBO crystals

    CERN Document Server

    Wen, Xin; Wang, Junmin


    A continuous-wave Ti:sapphire laser at 795 nm is frequency doubled in a bow-tie type enhancement four-mirror ring cavity with LiB3O5 (LBO), BiB3O6 (BiBO), and periodically polled KTiOPO4 (PPKTP) crystals, respectively. The properties of 397.5 nm ultra-violet (UV) output power, beam quality, stability for these different nonlinear crystals are investigated and compared. For PPKTP crystal, the highest doubling efficiency of 58.1% is achieved from 191 mW of 795 nm mode-matched fundamental power to 111 mW of 397.5 nm UV output. For LBO crystal, with 1.34 W of mode-matched 795 nm power, 770 mW of 397.5 nm UV output is achieved, implying a doubling efficiency of 57.4%. For BiBO crystal, with 323 mW of mode-matched 795 nm power, 116 mW of 397.5 nm UV output is achieved, leading to a doubling efficiency of 35.9%. The generated UV radiation has potential applications in the fields of quantum physics

  5. Comparison of Test Procedures and Energy Efficiency Criteria in Selected International Standards & Labeling Programs for Copy Machines, External Power Supplies, LED Displays, Residential Gas Cooktops and Televisions

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Nina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)


    This report presents a technical review of international minimum energy performance standards (MEPS), voluntary and mandatory energy efficiency labels and test procedures for five products being considered for new or revised MEPS in China: copy machines, external power supply, LED displays, residential gas cooktops and flat-screen televisions. For each product, an overview of the scope of existing international standards and labeling programs, energy values and energy performance metrics and description and detailed summary table of criteria and procedures in major test standards are presented.

  6. Kinetics and efficiency displayed by supported and suspended TiO2 catalysts applied to the disinfection of Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    Majdi Kacem; Gael Plantard; Nathalie Wery; Vincent Goetz


    TiO2-mediated photocatalysis is widely used in a variety of applications and products in the envi-ronmental and energy fields, including photoelectrochemical conversion, self-cleaning surfaces, and especially water purification systems. The dimensionality of the structure of a TiO2 material can affect its properties, functions, and more specifically, its photocatalytic performance. In this work, the photocatalytic inactivation of Gram-negative Escherichia coli using three photocatalysts, differ-ing in their structure and other characteristics, was studied in a batch reactor under UVA light. The aim was to establish the disinfection efficiency of solid TiO2 compared with that of suspended cata-lysts, widely considered as reference cases for photocatalytic water disinfection. The bacterial inac-tivation profiles obtained showed that: (1) the photoinactivation was exclusively related to the quantity of photons retained per unit of treated volume, irrespective of the characteristics of the photocatalyst and the emitted light flux densities;(2) across the whole UV light range studied, each of the photocatalytic solids was able to achieve more than 2 log bacterial inactivation with less than 2 h UV irradiation;(3) none of the used catalysts achieved a total bacterial disinfection during the treatment time. For each of the catalysts the quantum yield has been assessed in terms of disinfec-tion efficiency, the 2D material showed almost the same performance as those of suspended cata-lysts. This catalyst is promising for supported photocatalysis applications.

  7. From vertical-cavities to hybrid metal/photonic-crystal nanocavities: Towards high-efficiency nanolasers

    CERN Document Server

    Kim, Se-Heon; Scherer, Axel


    We provide a numerical study showing that a bottom reflector is indispensable to achieve unidirectional emission from a photonic-crystal (PhC) nanolaser. First, we study a PhC slab nanocavity suspended over a flat mirror formed by a dielectric or metal substrate. We find that the laser's vertical emission can be enhanced by more than a factor of six compared with the device in the absence of the mirror. Then, we study the situation where the PhC nanocavity is in contact with a flat metal surface. The underlying metal substrate may serve as both an electrical current pathway and a heat sink, which would help achieve continuous-wave lasing operation at room-temperature. The design of the laser emitting at 1.3 um reveals that relatively high cavity Q of over 1,000 is achievable assuming room-temperature gold as a substrate. Furthermore, linearly-polarized unidirectional vertical emission with the radiation efficiency over 50 % can be achieved. Finally, we discuss how this hybrid design relates to various plasmon...

  8. In Situ Doping Strategy for the Preparation of Conjugated Triazine Frameworks Displaying Efficient CO2 Capture Performance. (United States)

    Zhu, Xiang; Tian, Chengcheng; Veith, Gabriel M; Abney, Carter W; Dehaudt, Jérémy; Dai, Sheng


    An in situ doping strategy has been developed for the generation of a novel family of hexaazatriphenylene-based conjugated triazine frameworks (CTFs) for efficient CO2 capture. The resulting task-specific materials exhibit an exceptionally high CO2 uptake capacity (up to 4.8 mmol g(-1) at 297 K and 1 bar). The synergistic effects of ultrananoporosity and rich N/O codoped CO2-philic sites bestow the framework with the highest CO2 adsorption capacity among known porous organic polymers (POPs). This innovative approach not only enables superior CO2 separation performance but also provides tunable control of surface features on POPs, thereby affording control over bulk material properties. We anticipate this novel strategy will facilitate new possibilities for the rational design and synthesis of nanoporous materials for carbon capture.

  9. MimoPro: a more efficient Web-based tool for epitope prediction using phage display libraries

    Directory of Open Access Journals (Sweden)

    Guo William W


    Full Text Available Abstract Background A B-cell epitope is a group of residues on the surface of an antigen which stimulates humoral responses. Locating these epitopes on antigens is important for the purpose of effective vaccine design. In recent years, mapping affinity-selected peptides screened from a random phage display library to the native epitope has become popular in epitope prediction. These peptides, also known as mimotopes, share the similar structure and function with the corresponding native epitopes. Great effort has been made in using this similarity between such mimotopes and native epitopes in prediction, which has resulted in better outcomes than statistics-based methods can. However, it cannot maintain a high degree of satisfaction in various circumstances. Results In this study, we propose a new method that maps a group of mimotopes back to a source antigen so as to locate the interacting epitope on the antigen. The core of this method is a searching algorithm that is incorporated with both dynamic programming (DP and branch and bound (BB optimization and operated on a series of overlapping patches on the surface of a protein. These patches are then transformed to a number of graphs using an adaptable distance threshold (ADT regulated by an appropriate compactness factor (CF, a novel parameter proposed in this study. Compared with both Pep-3D-Search and PepSurf, two leading graph-based search tools, on average from the results of 18 test cases, MimoPro, the Web-based implementation of our proposed method, performed better in sensitivity, precision, and Matthews correlation coefficient (MCC than both did in epitope prediction. In addition, MimoPro is significantly faster than both Pep-3D-Search and PepSurf in processing. Conclusions Our search algorithm designed for processing well constructed graphs using an ADT regulated by CF is more sensitive and significantly faster than other graph-based approaches in epitope prediction. MimoPro is a

  10. Chiral crystal of a C2v-symmetric 1,3-diazaaulene derivative showing efficient optical second harmonic generation

    KAUST Repository

    Ma, Xiaohua


    Achiral nonlinear optical (NLO) chromophores 1,3-diazaazulene derivatives, 2-(4â€-aminophenyl)-6-nitro-1,3-diazaazulene (APNA) and 2-(4â€-N,N-diphenylaminophenyl)-6-nitro-1,3-diazaazulene (DPAPNA), were synthesized with high yield. Despite the moderate static first hyperpolarizabilities (β0) for both APNA [(136 ± 5) à - 10-30 esu] and DPAPNA [(263 ± 20) à - 10-30 esu], only APNA crystal shows a powder efficiency of second harmonic generation (SHG) of 23 times that of urea. It is shown that the APNA crystallization driven cooperatively by the strong H-bonding network and the dipolar electrostatic interactions falls into the noncentrosymmetric P2 12121 space group, and that the helical supramolecular assembly is solely responsible for the efficient SHG response. To the contrary, the DPAPNA crystal with centrosymmetric P-1 space group is packed with antiparalleling dimmers, and is therefore completely SHG-inactive. 1,3-Diazaazulene derivatives are suggested to be potent building blocks for SHG-active chiral crystals, which are advantageous in high thermal stability, excellent near-infrared transparency and high degree of designing flexibility. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 Optical crystals based on 1,3-diazaazulene derivatives are reported as the first example of organic nonlinear optical crystal whose second harmonic generation activity is found to originate solely from the chirality of their helical supramolecular orientation. The strong H-bond network forming between adjacent choromophores is found to act cooperatively with dipolar electrostatic interactions in driving the chiral crystallization of this material. Copyright © 2011 Wiley Periodicals, Inc.

  11. An Exopolysaccharide-Deficient Mutant of Lactobacillus rhamnosus GG Efficiently Displays a Protective Llama Antibody Fragment against Rotavirus on Its Surface. (United States)

    Álvarez, Beatriz; Krogh-Andersen, Kasper; Tellgren-Roth, Christian; Martínez, Noelia; Günaydın, Gökçe; Lin, Yin; Martín, M Cruz; Álvarez, Miguel A; Hammarström, Lennart; Marcotte, Harold


    Rotavirus is the leading cause of infantile diarrhea in developing countries, where it causes a high number of deaths among infants. Two vaccines are available, being highly effective in developed countries although markedly less efficient in developing countries. As a complementary treatment to the vaccines, a Lactobacillus strain producing an anti-rotavirus antibody fragment in the gastrointestinal tract could potentially be used. In order to develop such an alternative therapy, the effectiveness of Lactobacillus rhamnosus GG to produce and display a VHH antibody fragment (referred to as anti-rotavirus protein 1 [ARP1]) on the surface was investigated. L. rhamnosus GG is one of the best-characterized probiotic bacteria and has intrinsic antirotavirus activity. Among four L. rhamnosus GG strains [GG (CMC), GG (ATCC 53103), GG (NCC 3003), and GG (UT)] originating from different sources, only GG (UT) was able to display ARP1 on the bacterial surface. The genomic analysis of strain GG (UT) showed that the genes welE and welF of the EPS cluster are inactivated, which causes a defect in exopolysaccharide (EPS) production, allowing efficient display of ARP1 on its surface. Finally, GG (UT) seemed to confer a level of protection against rotavirus-induced diarrhea similar to that of wild-type GG (NCC 3003) in a mouse pup model, indicating that the EPS may not be involved in the intrinsic antirotavirus activity. Most important, GG (EM233), a derivative of GG (UT) producing ARP1, was significantly more protective than the control strain L. casei BL23. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. High Efficient Laser Operation of the Nd:KGd(WO4)2 Crystal Grown by Flux Method

    Institute of Scientific and Technical Information of China (English)

    LUO Zun-Du; CHEN Xue-Yuan; TU Chao-Yang; J. J. Romero; J. Garcia Sole


    The laser performance of Neodymium-doped potassium gadolinium tungstate (Nd:KGd(WO4)2) crystal was studied by using Ti:Sapphire laser as the pump source. The maximum optical-to-optical efficiencies for the 1.067 and 1.3 μm laser outputs were measured to be 60% and 32.3%, respectively. The internal loss coefficient of the crystal for 1.067 μm laser was estimated to be as low as 0.004 cm-1. The oscillation thresholds at 1.067 and 1.3 μm for different output transmittances are also given.

  13. Development of high-efficiency solar cells on copper indium selenide single crystals (cadmium sulfide, zinc oxide)

    Energy Technology Data Exchange (ETDEWEB)

    Yip, Lap Sum


    Photovoltaic cells with a ZnO/CdS/CuInSe{sub 2} structure were fabricated on bulk CuInSe{sub 2} substrates. Conversion efficiencies of more than or near 10 per cent were obtained on cells with an active area and without the use of antireflection coating. Copper indium selenide single crystals can be used as absorbers in thin film solar cells. In this study, the single crystals were grown by a horizontal Bridgman method. An annealing of the CuInSe{sub 2} substrate before the CdS deposition was found to be essential in obtaining high photovoltaic performance.

  14. Oblique incidence effect on steering efficiency of liquid crystal polarization gratings used for optical phased array beam steering amplification (United States)

    Xiangjie, Zhao; Jiazhu, Duan; Dayong, Zhang; Cangli, Liu; Yongquan, Luo


    A liquid crystal polarization grating (LCPG) is proposed that amplifies the steering angle of a liquid crystal optical phased array for non-mechanical beam steering, taking advantage of its high steering efficiency under normal incidence. However, oblique incidence may play an important role in the overall steering efficiency. The effect of oblique incidence on steering efficiency of a LCPG was analyzed by numerically solving the extended Jones matrix and considering propagation crosstalk. The results indicate that the outgoing laser beam is amplitude-modulated under the effect of oblique incidence and behaves as a sinusoidal-modulated amplitude grating, which diffracts certain energies to non-blazed orders. Over-oblique incidence may even eliminate the steering effect of the incident beam. The modulation depth of the induced amplitude grating was found to be proportional to the product of sinusoidal value of oblique incidence angle and the LC layer thickness, and inversely proportional to the periodic pitch length of the LCPG. Both in-plane incidence and out-of-plane incidence behave similarly to influence the steering efficiency. Finally, the overall steering efficiency for cascaded LCPGs was analyzed and a difference of up to 11 % steering efficiency can be induced between different LCPG configurations, even without considering the over-oblique incidence effect. Both the modulation depth and final steering efficiency can be optimized by varying the LC birefringence and layer thickness.

  15. Oblique incidence effect on steering efficiency of liquid crystal polarization gratings used for optical phased array beam steering amplification (United States)

    Xiangjie, Zhao; Jiazhu, Duan; Dayong, Zhang; Cangli, Liu; Yongquan, Luo


    A liquid crystal polarization grating (LCPG) is proposed that amplifies the steering angle of a liquid crystal optical phased array for non-mechanical beam steering, taking advantage of its high steering efficiency under normal incidence. However, oblique incidence may play an important role in the overall steering efficiency. The effect of oblique incidence on steering efficiency of a LCPG was analyzed by numerically solving the extended Jones matrix and considering propagation crosstalk. The results indicate that the outgoing laser beam is amplitude-modulated under the effect of oblique incidence and behaves as a sinusoidal-modulated amplitude grating, which diffracts certain energies to non-blazed orders. Over-oblique incidence may even eliminate the steering effect of the incident beam. The modulation depth of the induced amplitude grating was found to be proportional to the product of sinusoidal value of oblique incidence angle and the LC layer thickness, and inversely proportional to the periodic pitch length of the LCPG. Both in-plane incidence and out-of-plane incidence behave similarly to influence the steering efficiency. Finally, the overall steering efficiency for cascaded LCPGs was analyzed and a difference of up to 11 % steering efficiency can be induced between different LCPG configurations, even without considering the over-oblique incidence effect. Both the modulation depth and final steering efficiency can be optimized by varying the LC birefringence and layer thickness.

  16. Genetic code translation displays a linear trade-off between efficiency and accuracy of tRNA selection (United States)

    Johansson, Magnus; Zhang, Jingji; Ehrenberg, Måns


    Rapid and accurate translation of the genetic code into protein is fundamental to life. Yet due to lack of a suitable assay, little is known about the accuracy-determining parameters and their correlation with translational speed. Here, we develop such an assay, based on Mg2+ concentration changes, to determine maximal accuracy limits for a complete set of single-mismatch codon–anticodon interactions. We found a simple, linear trade-off between efficiency of cognate codon reading and accuracy of tRNA selection. The maximal accuracy was highest for the second codon position and lowest for the third. The results rationalize the existence of proofreading in code reading and have implications for the understanding of tRNA modifications, as well as of translation error-modulating ribosomal mutations and antibiotics. Finally, the results bridge the gap between in vivo and in vitro translation and allow us to calibrate our test tube conditions to represent the environment inside the living cell. PMID:22190491

  17. Efficient Surface Display of Diisopropylfluorophosphatase (DFPase) in E. coli for Biodegradation of Toxic Organophosphorus Compounds (DFP and Cp). (United States)

    Latifi, Ali Mohammad; Karami, Ali; Khodi, Samaneh


    Compounds including organophosphorus pesticides (OPs) and chemical nerve agents are toxic compounds synthesized recently which disrupt the mechanisms of neural transmission. Therefore, a critical requirement is the development of a bio-refining technology to facilitate the biodegradation of organophosphorus pollutants. The diisopropylfluorophosphatase (DFPase, EC from the ganglion and brain of Loligo vulgaris acts on P-F bonds present in some OPs. Intracellular production of OPs-degrading enzymes or the use of native bacteria and fungi leads to a low degradation rate of OPs due to a mass transfer issue which reduces the overall catalytic efficiency. To overcome this challenge, we expressed DFPase on the surface of E. coli for the first time by employing the N-terminal domain of the ice nucleation protein (InaV-N) as an anchoring motif. Tracking the recombinant protein confirmed that DFPase is successfully located on the outer membrane. Further studies on its activity to degrade diisopropylfluorophosphate (DFP) showed its significant ability for the biodegradation of diisopropylfluorophosphate (DFP) with a specific activity of 500 U/mg of wet cell weight. Recombinant cells could also degrade chlorpyrifos (Cp) with an activity equivalent to a maximum value of 381.44 U/ml with a specific activity of 476.75 U/mg of cell, analyzed using HPLC technique. The optimum activity of purified DFPase was found at 30 °C. A more increased activity was also obtained in the presence of glucose-mineral-salt (GMS) supplemented with tryptone and 100 mg/L Co(2+) ion. These results highlight the high potential of the InaV-N anchoring domain to produce an engineered bacterium that can be used in the bioremediation of pesticide-contaminated environments.

  18. Mesoporous silica nanoparticles synthesized from liquid crystal display manufacturing extracts as a potential candidate for a drug delivery carrier: evaluation of their safety and biocompatibility

    Directory of Open Access Journals (Sweden)

    Lin YC


    Full Text Available Yu-Chih Lin,1 Liang-Yi Lin,2 Ming-Yi Gao,3 Yi-Ping Fang31Department of Environmental Engineering and Health, Yuanpei University, 2Institute of Environmental Engineering, National Chiao Tung University, 3Department of Biotechnology, Yuanpei University, Hsinchu, TaiwanAbstract: Mesoporous silica nanoparticles (MSNs were synthesized as a promising drug delivery carrier due to the large surface area and porous characteristics. Our previous study successfully recycled wastes from the liquid crystal display (LCD industry as the silica precursor. In this study, we substantiated the possibility of applying this material as a drug carrier. MSNs synthesized from the extraction of wastes from the manufacture of LCD panels were characterized as having an average diameter of 100 nm, a surface area of 788 m2/g, a uniform pore size distribution of 3.8 nm, and a pore volume of up to 1.04 cm3/g. Methotrexate and camptothecin were entrapped in MSNs at about 33.88% and 75.12%, respectively. The cell viability assay demonstrated that MSNs at 1 µg/mL had no significant influence on human lung fibroblast (WI-38 cells or ovarian cancer (ES-2 cells. A lactate dehydrogenase assay also indicated no inflammation occurred. Moreover, a hemolytic erythrocyte test indicated that the dose range of <100 µg/mL showed that 5% of erythrocytes were affected. After exposure to biofluids, the ordered structure was slightly degraded. The results revealed that MSNs synthesized from extraction of wastes from the manufacture of LCD panels had a good entrapment capacity for hydrophobic drugs and controllable safety conditions; they may be applied as a drug delivery carrier.Keywords: mesoporous silica nanoparticles (MSNs, waste recycle, drug delivery carrier, safety, biocompatibility

  19. Enhanced light extraction efficiency of plastic scintillator by photonic crystal prepared with a self-assembly method

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jinliang [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); Zhu, Zhichao [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China); Chen, Liang; Ouyang, Xiaoping [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); Liu, Bo, E-mail: [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China); Cheng, Chuanwei [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China); Hu, Jing; He, Shiyi [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); Wang, Zewei [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi’an, 710024 (China); College of Materials Science and Engineering, Xiangtan University, Xiangtan 411105 (China); Gu, Mu; Chen, Hong [Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China)


    Plastic scintillators are extensively used in various radiation measurement systems. However the total internal reflection decreases the scintillation light output, leading to a low detection efficiency especially in these weak signal detection situations. In the present investigation, we have designed a light extraction scheme based on the photonic crystal formed with a monolayer periodic array of polystyrene nanospheres by a self-assembly method. The photonic crystal coated on the surface of plastic scintillator can significantly enhance the light extraction by 120% compared with the plain reference sample under X-ray excitation, which is achieved by the principle of the coupling of evanescent field near the scintillator-air interface with the photonic crystal.

  20. Experimental realization of highly efficient broadband coupling of single quantum dots to a photonic crystal waveguide

    DEFF Research Database (Denmark)

    Lund-Hansen, Toke; Stobbe, Søren; Julsgaard, Brian;


    We present time-resolved spontaneous emission measurements of single quantum dots embedded in photonic crystal waveguides. Quantum dots that couple to a photonic crystal waveguide are found to decay up to 27 times faster than uncoupled quantum dots. From these measurements -factors of up to 0.89 ...

  1. Influence of L-alanine doping on crystalline perfection, SHG efficiency, optical and mechanical properties of KDP single crystals (United States)

    Shakir, Mohd.; Ganesh, V.; Riscob, B.; Maurya, K. K.; Wahab, M. A.; Bhagavannarayana, G.; Kishan Rao, K.


    Pure and L-alanine (LA) doped single crystals of potassium dihydrogen orthophosphate (KDP) were grown by slow evaporation solution technique (SEST) in aqueous solution at ambient temperature. Powder X-ray diffraction study was done to confirm the crystal system and lattice parameters of KDP. No additional phases were observed at all doping concentrations (1-7.5 mol%), which was further confirmed by FT-Raman spectroscopy analysis. The influence of LA doping on the crystalline perfection was assessed by high-resolution X-ray diffractometry (HRXRD) analysis. HRXRD studies revealed that the grown crystals could accommodate LA at the interstitial positions in the crystalline matrix of KDP up to some critical concentration without any deterioration in the crystalline perfection. Above this concentration, very low angle structural grain boundaries were developed and it seems that the excess LA above the critical concentration was segregated along the grain boundaries. The SHG efficiency was measured using the Kurtz powder technique. The relative SHG efficiency of the crystals was found to be increased with doping concentration up to 5 mol% and above this it decreases. Optical transmission study also revealed the same behavior with enhancement up to 5 mol% concentration and later decreased. The hardness values were found to be increased by increasing the doping concentration.

  2. Ultrastable, high efficiency picosecond green light generation using K3B6O10Br series nonlinear optical crystals (United States)

    Hou, Z. Y.; Xia, M. J.; Wang, L. R.; Xu, B.; Yan, D. X.; Meng, L. P.; Liu, L. J.; Xu, D. G.; Zhang, L.; Wang, X. Y.; Li, R. K.; Chen, C. T.


    Two perovskite-structure K3B6O10Br1-x Cl x (x  =  0 and 0.5) series nonlinear optical crystals were thoroughly investigated for their picosecond 532 nm laser pulses abilities and high power outputs were achieved via second harmonic generation (SHG) technique for the first time. SHG conversion efficiency of 57.3% with a 13.2 mm length K3B6O10Br (KBB) crystal was achieved using a laser source of pulse repetition rate of 10 Hz and pulse width of 25 ps, which is the highest conversion efficiency of ps visible laser based on KBB crystal. And by employing an 80 MHz, 10 ps fundamental laser beam, maximum power outputs of 12 W with K3B6O10Br0.5Cl0.5 (KBBC) and 11.86 W with KBB crystals were successfully demonstrated. Furthermore, the standard deviation jitters of the average power outputs are less than 0.6% and 1.17% by KBB and KBBC, respectively, showing ultrastable power stabilities favorable for practical applications. In addition, the other optical parameters including acceptance angle and temperature bandwidth were also investigated.

  3. Growth, spectral, linear and nonlinear optical characteristics of an efficient semiorganic acentric crystal: L-valinium L-valine chloride

    Energy Technology Data Exchange (ETDEWEB)

    Nageshwari, M.; Jayaprakash, P.; Kumari, C. Rathika Thaya [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604407, Tamil Nadu (India); Vinitha, G. [Department of Physics, School of Advanced Sciences, VIT Chennai, 600127 Tamil Nadu (India); Caroline, M. Lydia, E-mail: [PG & Research Department of Physics, Arignar Anna Govt. Arts College, Cheyyar 604407, Tamil Nadu (India)


    An efficient nonlinear optical semiorganic material L-valinium L-valine chloride (LVVCl) was synthesized and grown-up by means of slow evaporation process. Single crystal XRD evince that LVVCl corresponds to monoclinic system having acentric space group P2{sub 1}. The diverse functional groups existing in LVVCl were discovered with FTIR spectral investigation. The UV-Visible and photoluminescence spectrum discloses the optical and electronic properties respectively for the grown crystal. Several optical properties specifically extinction coefficient, reflectance, linear refractive index, electrical and optical conductivity were also determined. The SEM analysis was also carried out and it portrayed the surface morphology of LVVCl. The calculated value of laser damage threshold was 2.59 GW/cm{sup 2}. The mechanical and dielectric property of LVVCl was investigated employing microhardness and dielectric studies. The second and third order nonlinear optical characteristics of LVVCl was characterized utilizing Kurtz Perry and Z scan technique respectively clearly suggest its suitability in the domain of optics and photonics. - Graphical abstract: Good quality transparent single crystals of L-valinium L-valine chloride single crystal was grown by slow evaporation technique. The grown crystals were analyzed using different instrumentation methods to check its usefulness for the device fabrication. The determination of nonlinear refractive index (n{sub 2}), absorption coefficient (β) and third order nonlinear susceptibility was determined by Z scan technique, highlighted that LVVCl can serve as a promising candidate for opto electronic and nonlinear optical applications.

  4. An erosion sensor based on a quartz crystal microbalance for quantitative determination of the cleaning efficiency in an ultrasonic vessel. (United States)

    Jüschke, M; Koch, C; Dreyer, T


    The efficiency of ultrasonic cleaning vessels cannot be measured directly in an easy way. In the presented work, a sensor is developed which quantitatively measures the ablation of a test layer. The sensor element is a quartz crystal which is coated with a sacrificial layer. Small changes in mass of this layer can be measured by a frequency shift of the crystal oscillation. For measurements, a 10 MHz AT-cut quartz crystal was used in a cleaning vessel working at 44.9 kHz. To determine the frequency shift by the ablation of the test layer, the quartz crystal was driven by a frequency generator sweeping the frequency in the range of the resonance frequency and a characteristic frequency was determined. The test layer which was applied to the quartz crystal consisted of silica microparticles suspended in varnish. In a preliminary experiment using a commercial cleaner it could be shown that significant changes in resonance frequency by cavitation effect could be detected. The initial frequency shift of the sacrificial layer is reproducible within 10%. The test layer can be adapted to the conditions of the cleaning vessel. By changing the electrical input power of the vessel, a threshold in the cavitation erosion was found.

  5. Porous one-dimensional photonic crystals improve the power-conversion efficiency of dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Colodrero, Silvia; Mihi, Agustin; Ocana, Manuel; Miguez, Hernan [Instituto de Ciencia de Materiales de Sevilla (Spain), Consejo Superior de Investigaciones Cientificas Americo Vespucio; Haeggman, Leif; Boschloo, Gerrit; Hagfeldt, Anders [Department of Chemistry Center of Molecular Devices, Royal Institute of Technology, Stockholm (Sweden)


    The solar-to-electric power-conversion efficiency ({eta}) of dye-sensitized solar cells can be greatly enhanced by integrating a mesoporous, nanoparticle-based, 1D photonic crystal as a coherent scattering layer in the device. The photogenerated current is greatly improved without altering the open-circuit voltage of the cell, while keeping the transparency of the cell intact. Improved average {eta} values between 15% and 30% are attained. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  6. An efficient flashlamp-pumped laser tunable in the IR range and using chromium-activated forsterite crystals

    Energy Technology Data Exchange (ETDEWEB)

    Baryshevskii, V.G.; Voloshin, V.A.; Demidovich, S.A.; Kimaev, A.E.; Korzhik, M.V. (Belorusskii Gosudarstvennyi Universitet, Minsk (Belorussian SSR))


    Efficient frequency-tunable lasing was obtained from Mg2SiO4:Cr single crystals under flashlamp pumping. The feasibility of using chromium ion absorption bands localized in the UV region for optical pumping is demonstrated. Wavelength tuning in the 1170-1330 nm range was obtained in a selective resonator for an output-mirror reflection coefficient of 86 percent. This laser may find application in fiber-optic communications and laser-radar systems.

  7. A study of the quantum efficiency of multichannel relaxation in LiNbO3:Yb, Er crystals (United States)

    Stroganova, E. V.; Nalbantov, N. N.; Galutsky, V. V.; Yakovenko, N. A.


    Luminescence spectra of gradient-activated LiNbO3:Yb, Er crystals with predefined concentration profiles of the optical centers are studied in different spectral regions. The process of electronic excitation energy transfer in the Yb3+-Er3+ system inside the LiNbO3 matrix is calculated and dependences of the quantum efficiency of the up-conversion processes for the green and red luminescences of erbium ions on the time of excitation energy deactivation are obtained.

  8. JAVA Stereo Display Toolkit (United States)

    Edmonds, Karina


    This toolkit provides a common interface for displaying graphical user interface (GUI) components in stereo using either specialized stereo display hardware (e.g., liquid crystal shutter or polarized glasses) or anaglyph display (red/blue glasses) on standard workstation displays. An application using this toolkit will work without modification in either environment, allowing stereo software to reach a wider audience without sacrificing high-quality display on dedicated hardware. The toolkit is written in Java for use with the Swing GUI Toolkit and has cross-platform compatibility. It hooks into the graphics system, allowing any standard Swing component to be displayed in stereo. It uses the OpenGL graphics library to control the stereo hardware and to perform the rendering. It also supports anaglyph and special stereo hardware using the same API (application-program interface), and has the ability to simulate color stereo in anaglyph mode by combining the red band of the left image with the green/blue bands of the right image. This is a low-level toolkit that accomplishes simply the display of components (including the JadeDisplay image display component). It does not include higher-level functions such as disparity adjustment, 3D cursor, or overlays all of which can be built using this toolkit.

  9. High stable, high efficient ultraviolet laser with angle-phase-mismatching compensation by adjusting temperature of the nonlinear crystals (United States)

    Yang, Houwen; Wang, Bo; Wang, Junhua; Li, Xiaofang; Liu, Zhaojun; Cheng, Wenyong


    We demonstrated an ultraviolet laser at 355 nm using a type-I and a type-II phase-matching nonlinear optical crystal of LiB3O5 (LBO). A method of adjusting temperature for compensation is presented. The crystal temperature is controlled by proportional integral derivative (PID) thermal controllers with a  ±0.01 °C resolution. The value of wave vector mismatch, distance of light propagation in nonlinear crystals, effective nonlinear coefficient, theoretical analysis and calculation of conversion efficiency versus temperature are discussed. The experimental results show that the average output power of the 355 nm laser is 1.24 W with the pump power of 13.33 W, when the repetition frequency is 15 kHz. The pulse duration is 9.8 ns, and the beam quality factors are of Mx2   =  1.8, My2   =  1.7. The conversion efficiency from 808 nm to 355 nm laser is 9.3%, which nearly reaches the optimum value reported so far and is limited by the wavelength mismatch between the pumping and absorbing lasers. The 355 nm output power instability of the laser device is 0.45% in 2 h. A compact no-water-cooling ultraviolet laser with high stability and high efficiency is obtained.

  10. Quantification of re-absorption and re-emission processes to determine photon recycling efficiency in perovskite single crystals (United States)

    Fang, Yanjun; Wei, Haotong; Dong, Qingfeng; Huang, Jinsong


    Photon recycling, that is, iterative self-absorption and re-emission by the photoactive layer itself, has been speculated to contribute to the high open-circuit voltage in several types of high efficiency solar cells. For organic-inorganic halide perovskites that have yielded highly efficient photovoltaic devices, however, it remains unclear whether the photon recycling effect is significant enough to improve solar cell efficiency. Here we quantitatively evaluate the re-absorption and re-emission processes to determine photon recycling efficiency in hybrid perovskite with its single crystals by measuring the ratio of the re-emitted photons to the initially excited photons, which is realized by modulating their polarization to differentiate them. The photon recycling efficiencies are revealed to be less than 0.5% in CH3NH3PbI3 and CH3NH3PbBr3 single crystals under excitation intensity close to one sun, highlighting the intrinsically long carrier recombination lifetime instead of the photon-recycling-induced photon propagation as the origin of their long carrier diffusion length.

  11. The effect of substrate temperature and growth rate on the doping efficiency of single crystal boron doped diamond

    Energy Technology Data Exchange (ETDEWEB)

    Demlow, SN; Rechenberg, R; Grotjohn, T


    The substrate growth temperature dependence of the plasma gas-phase to solid-phase doping efficiency in single crystal, boron doped diamond (BDD) deposition is investigated. Single crystal diamond (SCD) is grown by microwave plasma assisted chemical vapor deposition (MPACVD) on high pressure, high temperature (HPHT) type Ib substrates. Samples are grown at substrate temperatures of 850-950 degrees C for each of five doping concentration levels, to determine the effect of the growth temperature on the doping efficiency and defect morphology. The substrate temperature during growth is shown to have a significant effect on the grown sample defect morphology, and a temperature dependence of the doping efficiency is also shown. The effect of the growth rate on the doping efficiency is discussed, and the ratio of the boron concentration in the gas phase to the flux of carbon incorporated into the solid diamond phase is shown to be a more predictive measure of the resulting boron concentration than the gas phase boron to carbon ratio that is more commonly reported. (C) 2014 Elsevier B.V. All rights reserved.

  12. Latest development of display technologies (United States)

    Gao, Hong-Yue; Yao, Qiu-Xiang; Liu, Pan; Zheng, Zhi-Qiang; Liu, Ji-Cheng; Zheng, Hua-Dong; Zeng, Chao; Yu, Ying-Jie; Sun, Tao; Zeng, Zhen-Xiang


    In this review we will focus on recent progress in the field of two-dimensional (2D) and three-dimensional (3D) display technologies. We present the current display materials and their applications, including organic light-emitting diodes (OLEDs), flexible OLEDs quantum dot light emitting diodes (QLEDs), active-matrix organic light emitting diodes (AMOLEDs), electronic paper (E-paper), curved displays, stereoscopic 3D displays, volumetric 3D displays, light field 3D displays, and holographic 3D displays. Conventional 2D display devices, such as liquid crystal devices (LCDs) often result in ambiguity in high-dimensional data images because of lacking true depth information. This review thus provides a detailed description of 3D display technologies.

  13. 基于柱面光栅的液晶三维自由立体显示%3D Autostereoscopic Liquid Crystal Display Based on Lenticular Lens

    Institute of Scientific and Technical Information of China (English)

    王琼华; 陶宇虹; 李大海; 赵仁亮; 赵悟翔


    根据双目视差原理和柱面光栅的分光特性研制了液晶三维自由立体显示器.该立体显示器由二维平板液晶显示器和柱面光栅有机耦合而成.采用九个视差图实现了三维静态、动态和视频的显示效果.一个19英寸的立体显示器具有相对应的平面显示器相同的亮度、对比度和色彩,其分辨率在垂直和水平方向都有合理的下降.该立体显示器的观看距离是(1000±500)mm,视角为 90°,可供多人不戴立体眼镜就能自由观看立体图像.%According to binocular parallax and the optical property of lenticular lens, a three-dimension (3D) au-tostereoscopic liquid crystal display was developed. The display is composed of a two-dimension (2D) fiat liquid crystal display and a lenticular lens sheet. Nine views are used to realize the display of 3D static, animation and video images. A 19-inch 3D monitor prototype presents the same brightness, contrast ratio and color as those of the corresponding 2D display. Only the resolution reduces on both the horizontal and vertical direction of the screen reasonably. The viewing distance is (1000±500)mm and viewing angle is 90°. Several viewers without wearing eyeglass can see 3D stereo images on the prototype of the display.

  14. Plate-shaped Yb:LuPO4 crystal for efficient CW and passively Q-switched microchip lasers (United States)

    Liu, Junhai; Wang, Lisha; Han, Wenjuan; Xu, Honghao; Zhong, Degao; Teng, Bing


    It is demonstrated that plate-shaped crystals of Yb:LuPO4, which are grown from spontaneous nucleation by high-temperature solution method, can be utilized to make microchip lasers operating in continuous-wave (CW) or passively Q-switched mode. Efficient operation of such a microchip laser, which is built with a 0.3 mm thick crystal plate in a 2 mm long plane-parallel cavity, is realized at room temperature. With 2.37 W of pump power absorbed, 1.45 W of CW output power is generated with a slope efficiency of 73%. When passively Q-switched with a Cr4+:YAG crystal plate as saturable absorber, the laser produces a maximum pulsed output power of 0.53 W at 1013.3 nm, at a pulse repetition rate of 23.8 kHz, the resulting pulse energy, duration, and peak power are 22.3 μJ, 4.0 ns, and 5.6 kW, respectively.

  15. Synthesis, structural, thermal, mechanical, second harmonic generation efficiency and laser damage threshold studies of 4-dimethylaminopyridinium-3,5-dicarboxybenzoate trihydrate single crystal (United States)

    Rajkumar, M.; Saravanabhavan, M.; Chandramohan, A.


    4-dimethylaminopyridinium-3,5-dicarboxybenzoate trihydrate was synthesized and single crystals grown by slow solvent evaporation solution growth technique at ambient temperature. The single crystal XRD analysis was carried out to establish the molecular structure of the title crystal. Further, the data indicate that the title salt crystallizes in orthorhombic crystal system with the non-centrosymmetric space group, Pna21. The established molecular structure was further confirmed by 1H and 13C NMR spectroscopic studies. The grown crystal has been subjected to FT-IR spectral study to identify the various functional groups. The UV-Vis-NIR transmission spectrum was recorded on powdered sample of crystal to determine the lower wavelength cut-off and optical band gap. The photoluminescence spectrum was recorded to investigate the luminescence properties of the salt crystal. The thermal and mechanical stabilities of the crystal were established by TG/DTA analyses and Vickers microhardness study, respectively. The dielectric studies of the grown crystal were executed at different temperatures as a function of frequency to investigate its electrical properties. The SHG efficiency of the title crystal was investigated and its value is 0.89 times that of KDP crystal. The laser damage threshold value is found to be 1.06 GW/cm2.

  16. Polymer-templated nucleation and crystal growth of perovskite films for solar cells with efficiency greater than 21% (United States)

    Bi, Dongqin; Yi, Chenyi; Luo, Jingshan; Décoppet, Jean-David; Zhang, Fei; Zakeeruddin, Shaik Mohammed; Li, Xiong; Hagfeldt, Anders; Grätzel, Michael


    The past several years have witnessed the rapid emergence of a class of solar cells based on mixed organic-inorganic halide perovskites. Today’s state-of-the-art perovskite solar cells (PSCs) employ various methods to enhance nucleation and improve the smoothness of the perovskite films formed via solution processing. However, the lack of precise control over the crystallization process creates a risk of forming unwanted defects, for example, pinholes and grain boundaries. Here, we introduce an approach to prepare perovskite films of high electronic quality by using poly(methyl methacrylate) (PMMA) as a template to control nucleation and crystal growth. We obtain shiny smooth perovskite films of excellent electronic quality, as manifested by a remarkably long photoluminescence lifetime. We realize stable PSCs with excellent reproducibility showing a power conversion efficiency (PCE) of up to 21.6% and a certified PCE of 21.02% under standard AM 1.5G reporting conditions.

  17. Efficient Mid-Infrared Supercontinuum Generation in Tapered Large Mode Area Chalcogenide Photonic Crystal Fibers

    DEFF Research Database (Denmark)

    Petersen, Christian Rosenberg; Engelsholm, Rasmus Dybbro; Markos, Christos


    Mid-infrared supercontinuum spanning from 1.8-9  μm with an output power of 41.5 mW is demonstrated by pumping tapered large mode area chalcogenide photonic crystal fibers using a 4 μm optical parametric source....

  18. Flexible Bistable Cholesteric Reflective Displays (United States)

    Yang, Deng-Ke


    Cholesteric liquid crystals (ChLCs) exhibit two stable states at zero field condition-the reflecting planar state and the nonreflecting focal conic state. ChLCs are an excellent candidate for inexpensive and rugged electronic books and papers. This paper will review the display cell structure,materials and drive schemes for flexible bistable cholesteric (Ch) reflective displays.

  19. Efficient Generation of Red and Blue Light in a Dual-Structure Periodically Poled LiTaO3 Crystal

    Institute of Scientific and Technical Information of China (English)

    何京良; 胡小鹏; 祝世宁; 朱永元; 闵乃本


    We demonstrate the efficient generation of red light at 671 nm and blue light at 447nm from a diode-pumped Q-switched 1342 nm Nd:YVO4 laser together with a periodically poled LiTaO3 (PPLT) crystal. The sample used in this experiment is a dual-structure PPLT crystal with the period of 14.9 μm for the second harmonic generation and that of 4.9μm for the third harmonic generation. The red and blue light, with the respective average power of 752 m W and 153 m W were obtained in a single path under an average fundamental power of 1.74 W, corresponding to the conversion efficiencies of 43.2% and 8.8%, respectively. These results indicate that the dual-structure PPLT can be used to construct a compact and efficient all-solid-state red-and-blue dual-wavelength laser.

  20. Efficient fiber-coupled single-photon source based on quantum dots in a photonic-crystal waveguide

    CERN Document Server

    Daveau, Raphaël S; Pregnolato, Tommaso; Liu, Jin; Lee, Eun H; Song, Jin D; Verma, Varun; Mirin, Richard; Nam, Sae Woo; Midolo, Leonardo; Stobbe, Søren; Srinivasan, Kartik; Lodahl, Peter


    Many photonic quantum information processing applications would benefit from a high brightness, fiber-coupled source of triggered single photons. Here, we present a fiber-coupled photonic-crystal waveguide single-photon source relying on evanescent coupling of the light field from a tapered out-coupler to an optical fiber. A two-step approach is taken where the performance of the tapered out-coupler is recorded first on an independent device containing an on-chip reflector. Reflection measurements establish that the chip-to-fiber coupling efficiency exceeds 80 %. The detailed characterization of a high-efficiency photonic-crystal waveguide extended with a tapered out-coupling section is then performed. The corresponding overall single-photon source efficiency is 10.9 % $\\pm$ 2.3 %, which quantifies the success probability to prepare an exciton in the quantum dot, couple it out as a photon in the waveguide, and subsequently transfer it to the fiber. The applied out-coupling method is robust, stable over time, ...

  1. Flat panel display - Impurity doping technology for flat panel displays

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Toshiharu [Advanced Technology Planning, Sumitomo Eaton Nova Corporation, SBS Tower 9F, 10-1, Yoga 4-chome, Setagaya-ku, 158-0097 Tokyo (Japan)]. E-mail:


    Features of the flat panel displays (FPDs) such as liquid crystal display (LCD) and organic light emitting diode (OLED) display, etc. using low temperature poly-Si (LTPS) thin film transistors (TFTs) are briefly reviewed comparing with other FPDs. The requirements for fabricating TFTs used for high performance FPDs and system on glass (SoG) are addressed. This paper focuses on the impurity doping technology, which is one of the key technologies together with crystallization by laser annealing, formation of high quality gate insulator and gate-insulator/poly-Si interface. The issues to be solved in impurity doping technology for state of the art and future TFTs are clarified.

  2. High efficiency, high energy second-harmonic generation of Nd glass laser radiation in large aperture CsLiB sub 6 O sub 1 sub 0 crystals

    CERN Document Server

    Kiriyama, H; Yamakawa, K


    We have demonstrated the generation of a high-energy green laser pulse using large aperture CsLiB sub 6 O sub 1 sub 0 (CLBO) crystals. A pulsed energy of 25 J at 532-nm was generated using the 1064-nm incident Nd:glass laser radiation with an energy of 34 J. High conversion efficiency of 74% at intensities of only 370 MW/cm sup 2 was obtained using a two-stage crystal architecture. This result represents the highest green pulse energy ever reported using the CLBO crystals. We discuss in detail the design and performance of SHG using CLBO crystals.

  3. Crystal structure of 4-benzylcarbamoyl-1-methylpyridin-1-ium iodide: an efficient multimodal antiviral drug

    Directory of Open Access Journals (Sweden)

    T. N. Drebushchak


    Full Text Available In the title compound, [MeC5H4NCONHCH2C6H5]I or C14H15N2O+·I−, a cation and an anion form an ionic pair linked by a strong N—H...I hydrogen bond. In the crystal, ionic pairs linked by weak C—H...I hydrogen bonds form infinite ribbons along the crystallographic a axis. Polymorphism screening varying crystallization solvents (water, acetone 90%–water, ethanol 90%–water, 2-propanol 90%–water, DMF, DMSO, methanol, acetonitrile and conditions (solution temperature, heating and cooling protocols did not reveal any other polymorphs than the one reported in this work.

  4. Microwave Assisted Efficient Synthesis and Crystal Structures of O-Hexadecalkylated Pyrogallol[4]arenes

    Institute of Scientific and Technical Information of China (English)

    CHEN Jiao; CHEN Weifeng; YAN Chaoguo


    Under microwave irradiation alkylation reactions of sixteen phenolic hydroxyl groups in tetrap-hydroxyphenylpyrogallol[4]arene with alkylating reagents such as n-butyl iodide,benzyl chloride,and ethyl a-chloroacetate were finished quickly in one step to give the fully O-alkylated products.The X-ray single crystal diffraction showed that the three peralkylated pyrogallol[4]arenes existed in rcttcis-trans-transconfiguration.

  5. Efficient optimization of hollow-core photonic crystal fiber design using the finite-element method

    DEFF Research Database (Denmark)

    Holzlöhner, Ronald; Burger, Sven; Roberts, John;


    We employ a finite-element (FE) solver with adaptive grid refinement to model hollow-core photonic crystal fibers (HC-PCFs) whose core is formed from 19 omitted cladding unit cells. We optimize the complete fiber geometry for minimal field intensity at material/air interfaces, which indicates low...... loss and high damage threshold, using multidimensional optimization. The optimal design shows a 99.8 % power fraction within the air and an overlap with a Gaussian mode of 96.9 %....

  6. Improvement of antigen detection efficiency with the use of two-dimensional photonic crystal as a substrate (United States)

    Dovzhenko, Dmitriy; Terekhin, Vladimir; Vokhmincev, Kirill; Sukhanova, Alyona; Nabiev, Igor


    Multiplex detection of different antigens in human serum in order to reveal diseases at the early stage is of interest nowadays. There are a lot of biosensors, which use the fluorescent labels for specific detection of analytes. For instance, common method for detection of antigens in human serum samples is enzyme-linked immunosorbent assay (ELISA). One of the most effective ways to improve the sensitivity of this detection method is the use of a substrate that could enhance the fluorescent signal and make it easier to collect. Two-dimensional (2D) photonic crystals are very suitable structures for these purposes because of the ability to enhance the luminescent signal, control the light propagation and perform the analysis directly on its surface. In our study we have calculated optimal parameters for 2D-dimensional photonic crystal consisting of the array of silicon nano-rods, fabricated such photonic crystal on a silicon substrate using reactive ion etching and showed the possibility of its efficient application as a substrate for ELISA detection of human cancer antigens.

  7. Efficient continuous-wave nonlinear frequency conversion in high-Q Gallium Nitride photonic crystal cavities on Silicon

    CERN Document Server

    Mohamed, Mohamed Sabry; Carlin, Jean-François; Minkov, Momchil; Gerace, Dario; Savona, Vincenzo; Grandjean, Nicolas; Galli, Matteo; Houdré, Romuald


    We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG) and third harmonic generation (THG) in suspended gallium nitride slab photonic crystal (PhC) cavities on silicon, under continuous-wave resonant excitation. Optimized two-dimensional PhC cavities with augmented far-field coupling have been characterized with quality factors as high as 4.4$\\times10^{4}$, approaching the computed theoretical values. The strong enhancement in light confinement has enabled efficient SHG, achieving normalized conversion efficiency of 2.4$\\times10^{-3}$ $W^{-1}$, as well as simultaneous THG. SHG emission power of up to 0.74 nW has been detected without saturation. The results herein validate the suitability of gallium nitride for integrated nonlinear optical processing.

  8. X-ray Luminescence Efficiency of GAGG:Ce Single Crystal Scintillators for use in Tomographic Medical Imaging Systems (United States)

    David, S. L.; Valais, I. G.; Michail, C. M.; Kandarakis, I. S.


    The purpose of the present study was to evaluate different scintillator crystal samples, with a cross section of 3×3mm2 and various thicknesses ranging from 4mm up to 20mm, of the new mixed Gd3Al2Ga3O12:Ce (GAGG:Ce) scintillator material under X-ray irradiation, for potential applications in Tomographic Medical Imaging systems. Evaluation was performed by determining the X-ray luminescence efficiency (XLE) (emitted light energy flux over incident X-ray energy flux) in energies employed in general X-ray imaging. For the luminescence efficiency measurements, the scintillator samples were exposed to X-rays using a BMI General Medical Merate tube, with rotating Tungsten anode and inherent filtration equivalent to 2 mm Al. X-ray tube voltages between 50 to 130 kV were selected. An additional 20 mm filtration was introduced to the beam to simulate beam quality alternation equivalent to a human body. The emitted light energy flux measurements were performed using an experimental set up comprising a light integration sphere coupled to an EMI 9798B photomultiplier tube which was connected to a Cary 401 vibrating reed electrometer. The GAGG:Ce sample with dimensions 3×3×10 mm3 exhibited higher XLE values, in the whole X- ray energy range examined. XLE value equal to 0.013 was recorded for this crystal at 130 kVp - a setting frequently used in Computed Tomography applications.

  9. Distorted asymmetric cubic nanostructure of soluble fullerene crystals in efficient polymer:fullerene solar cells. (United States)

    Kim, Youngkyoo; Nelson, Jenny; Zhang, Tong; Cook, Steffan; Durrant, James R; Kim, Hwajeong; Park, Jiho; Shin, Minjung; Nam, Sungho; Heeney, Martin; McCulloch, Iain; Ha, Chang-Sik; Bradley, Donal D C


    We found that 1-(3-methoxycarbonyl)propyl-1-phenyl-(6,6)C(61) (PCBM) molecules make a distorted asymmetric body-centered cubic crystal nanostructure in the bulk heterojunction films of reigoregular poly(3-hexylthiophene) and PCBM. The wider angle of distortion in the PCBM nanocrystals was approximately 96 degrees , which can be assigned to the influence of the attached side group to the fullerene ball of PCBM to bestow solubility. Atom concentration analysis showed that after thermal annealing the PCBM nanocrystals do preferentially distribute above the layer of P3HT nanocrystals inside devices.

  10. Photonic Crystal Optical Tweezers with High Efficiency for Live Biological Samples and Viability Characterization. (United States)

    Jing, Peifeng; Wu, Jingda; Liu, Gary W; Keeler, Ethan G; Pun, Suzie H; Lin, Lih Y


    We propose and demonstrate a new optical trapping method for single cells that utilizes modulated light fields to trap a wide array of cell types, including mammalian, yeast, and Escherichia coli cells, on the surface of a two-dimensional photonic crystal. This method is capable of reducing the required light intensity, and thus minimizing the photothermal damage to living cells, thereby extending cell viability in optical trapping and cell manipulation applications. To this end, a thorough characterization of cell viability in optical trapping environments was performed. This study also demonstrates the technique using spatial light modulation in patterned manipulation of live cell arrays over a broad area.

  11. Highly efficient coupling between a monolithically integrated photonic crystal cavity and a bus waveguide (United States)

    Debnath, Kapil; Welna, Karl; Ferrera, Marcello; Deasy, Kieran; Lidzey, David; Krauss, Thomas F.; O'Faolain, Liam


    We experimentally demonstrate a new optical filter design comprising of a photonic crystal cavity and a low index bus waveguide which are monolithically integrated on a silicon-on-insulator (SOI) platform. We have fabricated oxide clad PhC cavities with a silicon nitride waveguide positioned directly above, such that there is an overlap between the evanescent tails of the two modes. We have realised an extinction ratio of 7.5dB for cavities with total Q of 50,000.

  12. Efficient and accurate laser shaping with liquid crystal spatial light modulators

    Energy Technology Data Exchange (ETDEWEB)

    Maxson, Jared M.; Bartnik, Adam C.; Bazarov, Ivan V. [Cornell Laboratory for Accelerator-Based Sciences and Education, Cornell University, Ithaca, New York 14853 (United States)


    A phase-only spatial light modulator (SLM) is capable of precise transverse laser shaping by either functioning as a variable phase grating or by serving as a variable mask via polarization rotation. As a phase grating, the highest accuracy algorithms, based on computer generated holograms (CGHs), have been shown to yield extended laser shapes with <10% rms error, but conversely little is known about the experimental efficiency of the method in general. In this work, we compare the experimental tradeoff between error and efficiency for both the best known CGH method and polarization rotation-based intensity masking when generating hard-edged flat top beams. We find that the masking method performs comparably with CGHs, both having rms error < 10% with efficiency > 15%. Informed by best practices for high efficiency from a SLM phase grating, we introduce an adaptive refractive algorithm which has high efficiency (92%) but also higher error (16%), for nearly cylindrically symmetric cases.

  13. Spectrometric performances of high quantum efficiency multi and single anode PMTs coupled to LaBr3(Ce) crystal (United States)

    Cinti, Maria Nerina; Pani, Roberto; Pellegrini, Rosanna; Bennati, Paolo; Orlandi, Chiara; Fabbri, Andrea; Ridolfi, Stefano; Scafè, Raffaele


    High quantum efficiency semiconductor photodetectors have recently drawn the attention of the scientific community for their potential in the realization of a new class of scintillation imagers with very high energy and spatial resolution performance. However, this goal does not seem within easy reach, due to various technological issues such as, for example, the difficulty to scale the characteristics of a single detector to an imager with suitable dimensions. Lately a definite technical improvement in increasing quantum efficiency up to 42% for position sensitive photomultipliers was achieved. The aim of this work is thus to test this new technological progress and to study the possible implications in imaging applications. Four Hamamatsu PMTs were tested: two multi anode photomultipliers, one with a bialkali (27% quantum efficiency) and the other one with a super-bialkali photocathode (38% quantum efficiency), and two 1×1 in. PMTs, both equipped with an ultra bialkali photocathode (42% quantum efficiency). In particular one of the ultra bialkali PMT has also an increased efficiency of first dynode charge collection. The results were compared with the ones obtained with a reference PMT (Hamamatsu R6231), mainly used in spectroscopy. The PMTs were coupled to LaBr3(Ce), NaI(Tl) and LSO(Ce) continuous scintillation crystals. The tests were done using two independent electronic chains: one dedicated for spectroscopic application and a second one, using a multi wire 64 channel readout, for imaging applications. The super-bialkali MA-PMTs have shown high energy resolution, both with spectroscopic and imaging setup, highlighting the appropriateness of these devices for the development of imaging devices with high spectroscopic performance.

  14. Intrinsic carrier multiplication efficiency in bulk Si crystals evaluated by optical-pump/terahertz-probe spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, G.; Nagai, M., E-mail:, E-mail:; Ashida, M., E-mail:, E-mail: [Graduate School of Engineering Science, Osaka University, Osaka 560-8531 (Japan); Matsubara, E. [Graduate School of Engineering Science, Osaka University, Osaka 560-8531 (Japan); Department of Physics, Osaka Dental University, Hirakata, Osaka 573-1121 (Japan); Kanemitsu, Y. [Institute for Chemical Research, Kyoto University, Kyoto 611-0011 (Japan)


    We estimated the carrier multiplication efficiency in the most common solar-cell material, Si, by using optical-pump/terahertz-probe spectroscopy. Through close analysis of time-resolved data, we extracted the exact number of photoexcited carriers from the sheet carrier density 10 ps after photoexcitation, excluding the influences of spatial diffusion and surface recombination in the time domain. For incident photon energies greater than 4.0 eV, we observed enhanced internal quantum efficiency due to carrier multiplication. The evaluated value of internal quantum efficiency agrees well with the results of photocurrent measurements. This optical method allows us to estimate the carrier multiplication and surface recombination of carriers quantitatively, which are crucial for the design of the solar cells.

  15. Miniature information displays: primary applications (United States)

    Alvelda, Phillip; Lewis, Nancy D.


    Positioned to replace current liquid crystal display technology in many applications, miniature information displays have evolved to provide several truly portable platforms for the world's growing personal computing and communication needs. The technology and functionality of handheld computer and communicator systems has finally surpassed many of the standards that were originally established for desktop systems. In these new consumer electronics, performance, display size, packaging, power consumption, and cost have always been limiting factors for fabricating genuinely portable devices. The rapidly growing miniature information display manufacturing industry is making it possible to bring a wide range of highly anticipated new products to new markets.

  16. Uniform LED illuminator for miniature displays (United States)

    Medvedev, Vladimir; Pelka, David G.; Parkyn, William A.


    The Total Internally Reflecting (TIR) lens is a faceted structure composed of prismatic elements that collect a source's light over a much larger angular range than a conventional Fresnel lens. It has been successfully applied to the efficient collimation of light from incandescent and fluorescent lamps, and from light-emitting diodes (LEDs). A novel LED-powered collimating backlight is presented here, for uniformly illuminating 0.25'-diagonal miniature liquid- crystal displays, which are a burgeoning market for pagers, cellular phones, digital cameras, camcorders, and virtual- reality displays. The backlight lens consists of a central dual-asphere refracting section and an outer TIR section, properly curved with a curved exit face.

  17. Efficient Design Tool for 2D and 3D NIMS Photonic Crystals (United States)


    configurations will be considered in the designs:    Gold  nanoshell   3D  photonic  crystal:  core  (silica)  diameter  =  418nm,  gold  shell  thickness...into  the  frontier.  Some  metamaterials of new and novel  features  will be designed and synthesized.      PAY‐OFF: To further develop the existing...designs can  be expected. With the to‐be‐developed algorithms, some new and novel  features  of the metamaterials  will be achieved and found.     6

  18. A novel real space scattering theory: efficient characterization of colloidal crystals

    Energy Technology Data Exchange (ETDEWEB)

    Cabrillo, C; Capitan, M J [Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain); Enciso, E; Cabanas, A [Facultad de Ciencias Quimicas, Departamento de Quimica Fisica I, Universidad Complutense, E-28040, Madrid (Spain); Torralvo, M J [Facultad de Ciencias QuImicas, Departamento de Quimica Inorganica, Universidad Complutense, E-28040, Madrid (Spain); Alvarez, J [Departamento de Fisica de la Materia Condensada, Facultad de Ciencias, Universidad Autonoma de Madrid, Fco. Tomas y Valiente 7, E-28049, Madrid (Spain); Bermejo, F J, E-mail: ccabrilo@foton0.iem.csic.e [Instituto de Estructura de la Materia, Unidad Asociada CSIC, Facultad de Ciencia y TecnologIa, Universidad del PaIs Vasco / EHU, P. Box 644, E-48080, Bilbao (Spain)


    Recent advances in self-organized 3D ordered structures of submicron particles as colloidal crystals demand a precise quantitative characterization of the produced nano-structures. Small angle scattering is the technique of choice for such a task but a comprehensive quantitative modeling of the measurements is far from being straightforward. We have developed a theory based in the pair distances distribution which take into the account orientational, positional and staking disorder as well as finite size effects. We show also how the radial scattering length density of the constituent particles, essential for a comprehensive modeling of the experimental data, can be estimated from the position of the form factor local minima. The results reduce to sums of analytical functions over the distribution of pair distances and as such, are suitable for easy (automatic) parallelization.

  19. Synthesis, growth, characterisation and laser damage threshold studies of N,N-dimethylanilinium-3-carboxy-4-hydroxybenzenesulphonate crystal: An efficient SHG material for electro-optic applications (United States)

    Rajkumar, M.; Chandramohan, A.


    An NLO active organic proton transfer complex salt, N,N-Dimethylanilinium-3-carboxy-4-hydroxybenzenesulphonate has been synthesized and single crystals grown by slow solvent evaporation solution growth technique at ambient temperature. The synthesized salt was characterized by Uv-visible absorption, UV-vis-NIR transmission spectral studies and elemental analysis. The formation of the salt and the crystal structure have been confirmed by single crystal X-ray diffraction (XRD) analysis and the title crystal belongs to monoclinic crystal system with the non-centrosymmetric space group, Pc. The FT-IR spectrum was recorded to confirm the presence of various functional groups in the grown crystal. The molecular structure of the crystal was further confirmed by 1H and 13C NMR spectra. The TG/DTA analyses were carried out to establish the thermal stability of the title crystal. The dielectric constant and dielectric loss have been studied as a function of frequency at different temperatures. The presence of SHG and its conversion efficiency was measured by employing the modified Kurtz and Perry powder technique. The laser damage threshold value of the title crystal was determined using a Nd:YAG laser with the wavelength of 1064 nm.

  20. Phosphors for flat panel emissive displays

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M.T.; Walko, R.J.; Phillips, M.L.F.


    An overview of emissive display technologies is presented. Display types briefly described include: cathode ray tubes (CRTs), field emission displays (FEDs), electroluminescent displays (ELDs), and plasma display panels (PDPs). The critical role of phosphors in further development of the latter three flat panel emissive display technologies is outlined. The need for stable, efficient red, green, and blue phosphors for RGB fall color displays is emphasized.

  1. Research on Color Temperature and Color Reproduction Performance Based on Four Primary Colors Liquid Crystal Display%四元色液晶显示器色温与色重显性能的研究

    Institute of Scientific and Technical Information of China (English)

    李彦; 王静; 李娜; 李桂苓


    Based on the data of the test by choosing seven color temperatures and testing the colorimetric parameters of the four primary colors liquid crystal display, the relations of the color temperature and the brightness, chroma, tone, color gamut coverage of the liquid crystal display are analyzed. The result shows that while the color temperature rises up, the brightness of the LCD increases, and the color gamut coverage decreases with the distortion of some color tones and chromas.%选择7种色温,分别测试了四元色液晶显示器的色度参数,并基于测试数据,分析了色温与液晶显示器亮度、彩度、色调和色域覆盖率的关系.结果表明,色温升高时,液晶显示器的亮度加大,色域覆盖率减小,还引起某些颜色色调和彩度失真.

  2. Enhancement in second harmonic generation efficiency, laser damage threshold and optical transparency of Mn 2+ doped L-alanine crystals: A correlation with crystalline perfection (United States)

    Kushwaha, S. K.; Rathee, S. P.; Maurya, K. K.; Bhagavannarayana, G.


    Effect on crystalline perfection, second harmonic generation (SHG) efficiency, laser damage threshold (LDT) and optical transparency due to Mn 2+ doping in L-alanine crystals has been investigated. The crystalline perfection of pure and doped crystals was evaluated by high-resolution X-ray diffractometry, which revealed the improvement in the crystalline perfection at low and moderate doping concentrations. At moderate and high concentrations, the Mn 2+ ions were found to be incorporated predominantly at the interstitial sites of the crystalline matrix. The actual incorporated amount of dopants in the crystals was analyzed by atomic absorption spectroscopy. The optical transparency, SHG efficiency, and laser damage threshold of the grown crystals with different concentrations of Mn 2+ were investigated. From these studies it is revealed that Mn 2+ doping lead to a considerable enhancement in the measured nonlinear optical properties with a correlation on crystalline perfection.

  3. 8% Efficient thin-film polycrystalline-silicon solar cells based on aluminium-induced crystallization and thermal CVD

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, I.; Carnel, L.; Van Gestel, D.; Beaucarne, G.; Poortmans, J. [IMEC VZW, Leuven (Belgium)


    A considerable cost reduction could be achieved in photovoltaics if efficient solar cells could be made from polycrystalline-silicon (pc-Si) thin films on inexpensive substrates. We recently showed promising solar cells results using pc-Si layers obtained by aluminium-induced crystallization (AlC) of amorphous silicon in combination with thermal chemical vapor deposition (CVD). To obtain highly efficient pc-Si solar cells, however, the material quality has to be optimized and cell processes different from those applied for standard bulk-Si solar cells have to be developed. In this work, we present the different process steps that we recently developed to enhance the efficiency of pc-Si solar cells on alumina substrates made by AlC in combination with thermal CVD. Our present pc-Si solar cell process yields cells in substrate configuration with efficiencies so far of up to 8.0%. Spin-on oxides are used to smoothen the alumina substrate surface to enhance the electronic quality of the absorber layers. The cells have heterojunction emitters consisting of thin a-Si layers that yield much higher V{sub oc} values than classical diffused emitters. Base and emitter contacts are on top of the cell in interdigitated finger patterns, leading to fill factors above 70%. The front surface of the cells is plasma textured to increase the current density. Our present pc-Si solar cell efficiency of 8% together with the fast progression that we have made over the last few years indicate the large potential of pc-Si solar cells based on the AlC seed layer approach. (author)

  4. Crystal structure and mechanical properties of spark plasma sintered Cu2Se: An efficient photovoltaic and thermoelectric material (United States)

    Tyagi, Kriti; Gahtori, Bhasker; Bathula, Sivaiah; Jayasimhadri, M.; Sharma, Sakshi; Singh, Niraj Kumar; Haranath, D.; Srivastava, A. K.; Dhar, Ajay


    Copper selenide (Cu2Se) based materials are currently being investigated globally for efficient photovoltaic and thermoelectric (TE) device applications. Despite having enormous device potential its crystal structure and mechanical properties are still not fully explored owing to its complex behavior. Stereographic projection is one of such useful tools to estimate the crystallography of the material conclusively. In the current study, the crystal structure of α and β-phases of Cu2Se was determined by its stereographic projections in reciprocal space. Further, mechanical properties of Cu2Se are highly important to avoid catastrophic failure and ensure longevity of the TE devices made out of these materials. Cu2Se exhibited the compressive strength of 45 MPa with 3% of plastic strain and a fracture toughness value of 2±0.02 MPa√m, the latter being significantly higher than that of the other known TE materials. Finally, thermal shock resistance, which is one of the crucial parameters for the stability and longevity of the device applications, was calculated to be 281±12 W m-1. Superior mechanical properties coupled with highly reported thermoelectric behavior makes Cu2Se as a potential candidate for green energy generation.

  5. Growth, spectral, linear and nonlinear optical characteristics of an efficient semiorganic acentric crystal: L-valinium L-valine chloride (United States)

    Nageshwari, M.; Jayaprakash, P.; Kumari, C. Rathika Thaya; Vinitha, G.; Caroline, M. Lydia


    An efficient nonlinear optical semiorganic material L-valinium L-valine chloride (LVVCl) was synthesized and grown-up by means of slow evaporation process. Single crystal XRD evince that LVVCl corresponds to monoclinic system having acentric space group P21. The diverse functional groups existing in LVVCl were discovered with FTIR spectral investigation. The UV-Visible and photoluminescence spectrum discloses the optical and electronic properties respectively for the grown crystal. Several optical properties specifically extinction coefficient, reflectance, linear refractive index, electrical and optical conductivity were also determined. The SEM analysis was also carried out and it portrayed the surface morphology of LVVCl. The calculated value of laser damage threshold was 2.59 GW/cm2. The mechanical and dielectric property of LVVCl was investigated employing microhardness and dielectric studies. The second and third order nonlinear optical characteristics of LVVCl was characterized utilizing Kurtz Perry and Z scan technique respectively clearly suggest its suitability in the domain of optics and photonics.

  6. Crystal Engineering for Low Defect Density and High Efficiency Hybrid Chemical Vapor Deposition Grown Perovskite Solar Cells. (United States)

    Ng, Annie; Ren, Zhiwei; Shen, Qian; Cheung, Sin Hang; Gokkaya, Huseyin Cem; So, Shu Kong; Djurišić, Aleksandra B; Wan, Yangyang; Wu, Xiaojun; Surya, Charles


    Synthesis of high quality perovskite absorber is a key factor in determining the performance of the solar cells. We demonstrate that hybrid chemical vapor deposition (HCVD) growth technique can provide high level of versatility and repeatability to ensure the optimal conditions for the growth of the perovskite films as well as potential for batch processing. It is found that the growth ambient and degree of crystallization of CH3NH3PbI3 (MAPI) have strong impact on the defect density of MAPI. We demonstrate that HCVD process with slow postdeposition cooling rate can significantly reduce the density of shallow and deep traps in the MAPI due to enhanced material crystallization, while a mixed O2/N2 carrier gas is effective in passivating both shallow and deep traps. By careful control of the perovskite growth process, a champion device with power conversion efficiency of 17.6% is achieved. Our work complements the existing theoretical studies on different types of trap states in MAPI and fills the gap on the theoretical analysis of the interaction between deep levels and oxygen. The experimental results are consistent with the theoretical predictions.

  7. Efficient Modeling of Coulomb Interaction Effect on Exciton in Crystal-Phase Nanowire Quantum Dot

    DEFF Research Database (Denmark)

    Taherkhani, Masoomeh; Gregersen, Niels; Mørk, Jesper


    The binding energy and oscillation strength of the ground-state exciton in type-II quantum dot (QD) is calculated by using a post Hartree-Fock method known as the configuration interaction (CI) method which is significantly more efficient than conventional methods like ab initio method. We show t...... that the Coulomb interaction between electron and holes in these structures considerably affects the transition dipole moment which is the key parameter of optical quantum gating in STIRAP (stimulated Raman adiabatic passage) process for implementing quantum gates [1], [2]....

  8. Study of a prototype high quantum efficiency thick scintillation crystal video-electronic portal imaging device. (United States)

    Samant, Sanjiv S; Gopal, Arun


    Image quality in portal imaging suffers significantly from the loss in contrast and spatial resolution that results from the excessive Compton scatter associated with megavoltage x rays. In addition, portal image quality is further reduced due to the poor quantum efficiency (QE) of current electronic portal imaging devices (EPIDs). Commercial video-camera-based EPIDs or VEPIDs that utilize a thin phosphor screen in conjunction with a metal buildup plate to convert the incident x rays to light suffer from reduced light production due to low QE (quantum efficiency (DQE). A theoretical expression of DQE(0) was developed to be used as a predictive model to propose improvements in the optics associated with the light detection. The prototype TSC provides DQE(0)=0.02 with its current imaging geometry, which is an order of magnitude greater than that for commercial VEPID systems and comparable to flat-panel imaging systems. Following optimization in the imaging geometry and the use of a high-end, cooled charge-coupled-device (CCD) camera system, the performance of the TSC is expected to improve even further. Based on our theoretical model, the expected DQE(0)=0.12 for the TSC system with the proposed improvements, which exceeds the performance of current flat-panel EPIDs. The prototype TSC provides high quality imaging even at subMU exposures (typical imaging dose is 0.2 MU per image), which offers the potential for daily patient localization imaging without increasing the weekly dose to the patient. Currently, the TSC is capable of limited frame-rate fluoroscopy for intratreatment visualization of patient motion at approximately 3 frames/second, since the achievable frame rate is significantly reduced by the limitations of the camera-control processor. With optimized processor control, the TSC is expected to be capable of intratreatment imaging exceeding 10 frames/second to monitor patient motion.

  9. Crystal structure of a human rhinovirus that displays part of the HIV-1 V3 loop and induces neutralizing antibodies against HIV-1. (United States)

    Ding, Jianping; Smith, Allen D; Geisler, Sheila C; Ma, Xuejun; Arnold, Gail Ferstandig; Arnold, Eddy


    We report the 2.7 A resolution structure of a chimeric rhinovirus, MN-III-2, that displays part of the HIV-1 gp120 V3 loop and elicits HIV-neutralizing antibodies. The V3 loop insert is dominated by two type I beta turns. The structures of two adjacent tripeptides resemble those of analogous segments in three Fab/V3 loop peptide complexes. Although two of the three corresponding antibodies bind and neutralize MN-III-2 well, only one of the three can bind without significant rearrangement. These results suggest that the V3 loop insert: (1) can share some local conformational similarity to V3 loop sequences presented on different structural frameworks; (2) must be able to adopt multiple conformations, even in a relatively constrained environment; and (3) may mimic the conformational variability of the epitope on HIV-1, increasing the likelihood of eliciting appropriate neutralizing immune responses.

  10. Split-step finite-difference time-domain method with perfectly matched layers for efficient analysis of two-dimensional photonic crystals with anisotropic media. (United States)

    Singh, Gurpreet; Tan, Eng Leong; Chen, Zhi Ning


    This Letter presents a split-step (SS) finite-difference time-domain (FDTD) method for the efficient analysis of two-dimensional (2-D) photonic crystals (PhCs) with anisotropic media. The proposed SS FDTD method is formulated with perfectly matched layer boundary conditions and caters for inhomogeneous anisotropic media. Furthermore, the proposed method is derived using the efficient SS1 splitting formulas with simpler right-hand sides that are more efficient and easier to implement. A 2-D PhC cavity with anisotropic media is used as an example to validate the efficiency of the proposed method.

  11. Efficiency

    NARCIS (Netherlands)

    I.P. van Staveren (Irene)


    textabstractThe dominant economic theory, neoclassical economics, employs a single economic evaluative criterion: efficiency. Moreover, it assigns this criterion a very specific meaning. Other – heterodox – schools of thought in economics tend to use more open concepts of efficiency, related to comm

  12. Efficient out-coupling of high-purity single photons from a coherent quantum dot in a photonic-crystal cavity

    CERN Document Server

    Madsen, K H; Liu, J; Javadi, A; Albrecht, S M; Yeo, I; Stobbe, S; Lodahl, P


    We demonstrate a single-photon collection efficiency of $(44.3\\pm2.1)\\%$ from a quantum dot in a low-Q mode of a photonic-crystal cavity with a single-photon purity of $g^{(2)}(0)=(4\\pm5)\\%$ and directly detect up to $962\\pm46$ kilocounts per second on a single-photon detector. The high collection efficiency is found to be broadband, as is confirmed by detailed numerical simulations. Cavity-enhanced efficient excitation of quantum dots is obtained through phonon-mediated excitation and under these conditions, single-photon indistinguishability measurements reveal long coherence times of up to $0.77\\pm0.19$ ns. Our work demonstrates that photonic crystals provide a very promising platform for highly integrated generation of coherent single photons including the efficient outcoupling of the photons from the photonic chip.

  13. Efficient out-coupling of high-purity single photons from a coherent quantum dot in a photonic-crystal cavity

    DEFF Research Database (Denmark)

    Madsen, Kristian Høeg; Ates, Serkan; Liu, J.


    We demonstrate a single-photon collection efficiency of (44.3 ± 2.1)% from a quantum dot in a low-Q mode of a photonic-crystal cavity with a single-photon purity of g(2)(0) = (4 ± 5)% recorded above the saturation power. The high efficiency is directly confirmed by detecting up to 962 ± 46...... kilocounts per second on a single-photon detector on another quantum dot coupled to the cavity mode. The high collection efficiency is found to be broadband, as is explained by detailed numerical simulations. Cavity-enhanced efficient excitation of quantum dots is obtained through phonon-mediated excitation...... and under these conditions, single-photon indistinguishability measurements reveal long coherence times reaching 0.77 ± 0.19 ns in a weak-excitation regime. Our work demonstrates that photonic crystals provide a very promising platform for highly integrated generation of coherent single photons including...

  14. Efficient loading of ethionamide in cyclodextrin-based carriers offers enhanced solubility and inhibition of drug crystallization. (United States)

    Wankar, Jitendra; Salzano, Giuseppina; Pancani, Elisabetta; Benkovics, Gabor; Malanga, Milo; Manoli, Francesco; Gref, Ruxandra; Fenyvesi, Eva; Manet, Ilse


    Ethionamide (ETH) is a second line antitubercular drug suffering from poor solubility in water and strong tendency to crystallize. These drawbacks were addressed by loading ETH in β-cyclodextrin (βCyD)-based carriers. The drug was incorporated in a molecular state avoiding crystallization even for long-term storage and obtaining a tenfold increased solubility up to 25mM. The binding of ETH to polymeric βCyD nanoparticles (pβCyD NPs) was investigated in neutral aqueous medium by means of solubility phase diagrams, circular dichroism (CD) and UV-vis absorption and compared with the corresponding βCyD monomer. The binding constants and the absolute CD spectra of the drug complexes were determined by global analysis of multiwavelength data from spectroscopic titrations. The spectroscopic and photophysical properties of the complexes evidenced an alcohol-like environment for ETH included in the cavity. Additionally, ETH was found to be located not only in βCyD cavities, but also in confined microdomains inside the crosslinked NPs. This double modality of complexation together with a slightly higher binding constant makes the utilization of pβCyD NPs preferable over the monomeric βCyDs. In order to pave the way to future in vitro experiments, fluorescein labeled pβCyDs were synthesized. Interestingly the FITC labeling did not hamper the encapsulation of ETH and the drug improved the fluorescent signal of FITC molecules. The βCyD-based carriers appeared as versatile "green" systems for efficient incorporation and future delivery of ETH. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Improvement of melt crystallization's efficiency for industrial applications. Final report 01-08-1990 - 31-03-1994

    NARCIS (Netherlands)

    Arkenbout, G.J.; Goede, R. de; Nienoord, M.; Verdoes, D.; Berg, E.P.G. van den; Geertman, R.; Bennema, P.; Neumann, M.; Ulrich, J.; Wellinghoff, G.; Kind, M.


    A research project was carried out by the University of Nijmegen, the University of Bremen, BASF and TNO to improve melt crystallization's efficienry in industrial applications. Both process options of growing crystal layers on the cooled wall of a heat exchanger and of growing crystals in suspensio

  16. Chirality versus dichroism: Competition and role in conical diffraction displayed from the Nd:Bi2ZnOB2O6 acentric biaxial laser crystal (United States)

    Brenier, A.; Majchrowski, A.; Michalski, E.


    We have grown acentric chiral Nd-doped BZBO single crystals by the Kyropoulos method, cut perpendicular to the optical axis. With a focused beam at wavelengths in the spectral domain of transparency with various polarizations, the conoscopy patterns revealed the specific role of chirality: disappearance of the optical axis replaced by two C-directions, linear polarization rotation and spiral patterns. The specific rotatory power was measured. The output near field exhibits the influence of chirality on the conical diffraction. Going to wavelengths in the spectral domain of absorption corresponding to the 4I9/2 → 4F5/2 Nd3+ transition, we first studied the chirality/dichroism competition from propagation along the C-directions, characterizing the circular and elliptic eigen-modes. We exhibited the wavelengths at which the ellipse degenerates linearly, signature of the chirality/dichroism balancing. The second aspect is the existence of the optical axis which can be restored if the dichroism is high enough. In this case a singular Voigt wave can propagate. From the experimental determination of the optical parameters, a theoretical description has been proposed, leading to quite well agreement in the far field (conoscopy) and in the near field (conical diffraction).

  17. Paring Down HIV Env: Design and Crystal Structure of a Stabilized Inner Domain of HIV-1 gp120 Displaying a Major ADCC Target of the A32 Region. (United States)

    Tolbert, William D; Gohain, Neelakshi; Veillette, Maxime; Chapleau, Jean-Philippe; Orlandi, Chiara; Visciano, Maria L; Ebadi, Maryam; DeVico, Anthony L; Fouts, Timothy R; Finzi, Andrés; Lewis, George K; Pazgier, Marzena


    Evidence supports a role of antibody-dependent cellular cytotoxicity (ADCC) toward transitional epitopes in the first and second constant (C1-C2) regions of gp120 (A32-like epitopes) in preventing HIV-1 infection and in vaccine-induced protection. Here, we describe the first successful attempt at isolating the inner domain (ID) of gp120 as an independent molecule that encapsulates the A32-like region within a minimal structural unit of the HIV-1 Env. Through structure-based design, we developed ID2, which consists of the ID expressed independently of the outer domain and stabilized in the CD4-bound conformation by an inter-layer disulfide bond. ID2 expresses C1-C2 epitopes in the context of CD4-triggered full-length gp120 but without any known neutralizing epitope present. Thus, ID2 represents a novel probe for the analysis and/or selective induction of antibody responses to the A32 epitope region. We also present the crystal structure of ID2 complexed with mAb A32, which defines its epitope.

  18. Technology Development for High-Efficiency Solar Cells and Modules Using Thin (<80 um) Single-Crystal Silicon Wafers Produced by Epitaxy: June 11, 2011 - April 30, 2013

    Energy Technology Data Exchange (ETDEWEB)

    Ravi, T. S.


    Final technical progress report of Crystal Solar subcontract NEU-31-40054-01. The objective of this 18-month program was to demonstrate the viability of high-efficiency thin (less than 80 um) monocrystalline silicon (Si) solar cells and modules with a low-cost epitaxial growth process.

  19. Technology Development for High-Efficiency Solar Cells and Modules Using Thin (<80 um) Single-Crystal Silicon Wafers Produced by Epitaxy: June 11, 2011 - April 30, 2013

    Energy Technology Data Exchange (ETDEWEB)

    Ravi, T. S.


    Final technical progress report of Crystal Solar subcontract NEU-31-40054-01. The objective of this 18-month program was to demonstrate the viability of high-efficiency thin (less than 80 um) monocrystalline silicon (Si) solar cells and modules with a low-cost epitaxial growth process.

  20. Generating Efficient Femtosecond Mid-infrared Pulse by Single Near-infrared Pump Wavelength in Bulk Nonlinear Crystal Without Phase-matching

    DEFF Research Database (Denmark)

    Zhou, Binbin; Guo, Hairun; Bache, Morten


    We experimentally demonstrate efficient mid-infrared pulse generation by dispersive wave radiation in bulk lithium niobate crystal. Femtosecond mid-IR pulses centering from 2.8-2.92 μm are generated using the single pump wavelengths from 1.25-1.45 μm. © 2014 Optical Society of America...

  1. Colorimetric evaluation of display performance (United States)

    Kosmowski, Bogdan B.


    The development of information techniques, using new technologies, physical phenomena and coding schemes, enables new application areas to be benefited form the introduction of displays. The full utilization of the visual perception of a human operator, requires the color coding process to be implemented. The evolution of displays, from achromatic (B&W) and monochromatic, to multicolor and full-color, enhances the possibilities of information coding, creating however a need for the quantitative methods of display parameter assessment. Quantitative assessment of color displays, restricted to photometric measurements of their parameters, is an estimate leading to considerable errors. Therefore, the measurements of a display's color properties have to be based on spectral measurements of the display and its elements. The quantitative assessment of the display system parameters should be made using colorimetric systems like CIE1931, CIE1976 LAB or LUV. In the paper, the constraints on the measurement method selection for the color display evaluation are discussed and the relations between their qualitative assessment and the ergonomic conditions of their application are also presented. The paper presents the examples of using LUV colorimetric system and color difference (Delta) E in the optimization of color liquid crystal displays.

  2. Universal Numeric Segmented Display

    CERN Document Server

    Azad, Md Abul kalam; Kamruzzaman, S M


    Segmentation display plays a vital role to display numerals. But in today's world matrix display is also used in displaying numerals. Because numerals has lots of curve edges which is better supported by matrix display. But as matrix display is costly and complex to implement and also needs more memory, segment display is generally used to display numerals. But as there is yet no proposed compact display architecture to display multiple language numerals at a time, this paper proposes uniform display architecture to display multiple language digits and general mathematical expressions with higher accuracy and simplicity by using a 18-segment display, which is an improvement over the 16 segment display.

  3. Bandgap-tailored NiO nanospheres: an efficient photocatalyst for the degradation of crystal violet dye solution (United States)

    Vahini, Raja; Kumar, Puvaneswaran Senthil; Karuthapandian, Swaminathan


    Bandgap-tailored NiO nanospheres were successfully synthesized by facile precipitation method for the first time and characterized by XRD, EDX, SEM, TEM, FTIR, UV and PL. Interestingly, the modification of the band gap was observed using UV-Vis (DRS) spectroscopy, and the observed band gap is 3.31 eV. The morphology of the materials was analysed by SEM and TEM which show the sphere like structures of NiO with the particle size of ~20 nm. The efficiency of the materials was examined by the degradation of crystal violet dye under UV light illumination. The complete degradation was achieved within 60 min, and the mechanism of the degradation were also been proposed. In addition, the degradation of rhodamine B (RhB) and methylene blue dye solution was also carried out to extend the practical applications of NiO nanospheres. The involvement of reactive oxidative species (ROS) was found out by trapping experiment, and the ROS is superoxide radical anion.

  4. Efficient functionalization of poly(styrene) beads immobilized metal nanoparticle catalysts for the reduction of crystal violet

    Indian Academy of Sciences (India)

    Eagambaram Murugan; Paramasivam Shanmugam


    Three types of new bead-shaped heterogeneous nanoparticle (NP) catalysts were synthesized by simplified procedures and studied for continuous reduction of crystal violet (CV) dye. The stabilizing agent, viz., 2-acryloxyethyltrimethyl ammonium chloride (PAC) was functionalized efficiently onto the surface of insoluble poly(styrene)-co-(vinyl benzyl chloride) beads (PS–PVBC) through surface-initiated atom transfer radical polymerization (SI-ATRP) to obtain insoluble bead matrix having intense surface functional groups labelled as PS–PVBC--PAC. These PS–PVBC–PAC beads in turn were used as a common matrix for individual immobilization of AgNPs, AuNPs and PdNPs by following the simple chemical reaction/reduction methods to yield the corresponding bead-shaped heterogeneous NP catalysts, viz., PS–PVBC--PAC–AgNPs, PS–PVBC--PAC–AuNPs and PS–PVBC--PAC–PdNPs. These catalysts were characterized by UV–Vis, FT-IR, SEM/EDAX and HRTEM techniques. The catalytic activity of these three types of catalysts were examined through the reduction of CV using NaBH4 as a reducing agent and it was observed that all these catalysts effectively accelerated the reaction. The superior catalyst, viz., PS–PVBC--PAC–AuNPs was again used for detail kinetic studies of the same reduction reaction.


    Energy Technology Data Exchange (ETDEWEB)

    K.R. Rajagopal; I.J. Rao


    The demand for increased efficiency of gas turbines used in power generation and aircraft applications has fueled research into advanced materials for gas turbine blades that can withstand higher temperatures in that they have excellent resistance to creep. The term ''Superalloys'' describes a group of alloys developed for applications that require high performance at elevated temperatures. Superalloys have a load bearing capacity up to 0.9 times their melting temperature. The objective of the investigation was to develop a thermodynamic model that can be used to describe the response of single crystal superalloys that takes into account the microstructure of the alloy within the context of a continuum model. Having developed the model, its efficacy was to be tested by corroborating the predictions of the model with available experimental data. Such a model was developed and it is implemented in the finite element software ABAQUS/STANDARD through a user subroutine (UMAT) so that the model can be used in realistic geometries that correspond to turbine blades.

  6. Growth, structure, crystalline perfection and characterization of Mg(II)-incorporated tris(thiourea)Zn(II) sulfate crystals: Enhanced second harmonic generation (SHG) efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Muthu, K. [Department of Chemistry, Annamalai University, Annamalainagar-608 002 (India); Bhagavannarayana, G. [Crystal Growth and X-ray Analysis Activity, Council of Scientific and Industrial Research, National Physical Laboratory, New Delhi-110 012 (India); Meenakshisundaram, S.P., E-mail: [Department of Chemistry, Annamalai University, Annamalainagar-608 002 (India)


    Highlights: Black-Right-Pointing-Pointer A small quantity incorporation of Mg(II)- enhances the SHG efficiency of ZTS. Black-Right-Pointing-Pointer Crystal stress is observed. Black-Right-Pointing-Pointer Structure of Mg(II)-incorporated ZTS is elucidated. Black-Right-Pointing-Pointer Crystalline perfection is evaluated by HRXRD. - Abstract: Single crystals of Mg(II)-incorporated tris(thiourea)Zn(II) sulfate (MZTS) have been grown from aqueous solution at room temperature by slow evaporation solution growth technique. The incorporation of Mg(II)- into the crystalline lattice was well confirmed by energy dispersive X-ray spectroscopy (EDS) and by single crystal X-ray diffraction technique. The reduction in the intensities observed in powder X-ray diffraction patterns of doped specimen and slight shifts in vibrational frequencies in FT-IR indicate the lattice stress as a result of doping. Thermal studies reveal the purity of the material and no decomposition is observed up to the melting point. High transmittance is observed in the visible region and the band gap energy is estimated by Kubelka-Munk algorithm. Surface morphology of doped material was observed by scanning electron microscopy (SEM). Decreased crystalline perfection by doping observed by high-resolution X-ray diffraction (HRXRD) analysis is justified by the crystal stress. Even a small quantity incorporation of Mg(II)- enhances the SHG efficiency significantly. The as-grown crystal is further characterized by microhardness and dielectric studies.

  7. An efficient light trapping scheme based on textured conductive photonic crystal back reflector for performance improvement of amorphous silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Peizhuan; Hou, Guofu, E-mail:; Huang, Qian; Zhao, Jing; Zhang, Jianjun, E-mail:; Ni, Jian; Zhang, Xiaodan; Zhao, Ying [Tianjin Key Laboratory of Photoelectronic Thin-Film Devices and Technique, Institute of Photoelectronics, Nankai University, Tianjin 300071 (China); Fan, QiHua [Department of Electrical Engineering and Computer Science, South Dakota State University, Brookings, South Dakota 57007 (United States)


    An efficient light trapping scheme named as textured conductive photonic crystal (TCPC) has been proposed and then applied as a back-reflector (BR) in n-i-p hydrogenated amorphous silicon (a-Si:H) solar cell. This TCPC BR combined a flat one-dimensional photonic crystal and a randomly textured surface of chemically etched ZnO:Al. Total efficiency enhancement was obtained thanks to the sufficient conductivity, high reflectivity and strong light scattering of the TCPC BR. Unwanted intrinsic losses of surface plasmon modes are avoided. An initial efficiency of 9.66% for a-Si:H solar cell was obtained with short-circuit current density of 14.74 mA/cm{sup 2}, fill factor of 70.3%, and open-circuit voltage of 0.932 V.

  8. High-efficiency deflection of high energy protons due to channeling along the 〈110〉 axis of a bent silicon crystal

    Directory of Open Access Journals (Sweden)

    W. Scandale


    Full Text Available A deflection efficiency of about 61% was observed for 400 GeV/c protons due to channeling, most strongly along the 〈110〉 axis of a bent silicon crystal. It is comparable with the deflection efficiency in planar channeling and considerably larger than in the case of the 〈111〉 axis. The measured probability of inelastic nuclear interactions of protons in channeling along the 〈110〉 axis is only about 10% of its amorphous level whereas in channeling along the (110 planes it is about 25%. High efficiency deflection and small beam losses make this axial orientation of a silicon crystal a useful tool for the beam steering of high energy charged particles.

  9. Highly efficient source for frequency-entangled photon pairs generated in a 3rd order periodically poled MgO-doped stoichiometric LiTaO3 crystal

    CERN Document Server

    Kim, Heonoh; Lee, Sang Min; Moon, Han Seb


    We present a highly efficient source for discrete frequency-entangled photon pairs based on spontaneous parametric down-conversion using 3rd order type-0 quasi-phase matching in a periodically poled MgO-doped stoichiometric LiTaO3 crystal pumped by a 355.66 nm laser. Correlated two-photon states were generated with automatic conservation of energy and momentum in two given spatial modes. These states have a wide spectral range, even under small variations in crystal temperature, which consequently results in higher discreteness. Frequency entanglement was confirmed by measuring two-photon quantum interference fringes without any spectral filtering.

  10. Synthesis, crystal structure, growth, optical and third order nonlinear optical studies of 8HQ2C5N single crystal - An efficient third-order nonlinear optical material

    Energy Technology Data Exchange (ETDEWEB)

    Divya Bharathi, M.; Ahila, G.; Mohana, J. [Department of Physics, Presidency College, Chennai 600005 (India); Chakkaravarthi, G. [Department of Physics, CPCL Polytechnic College, Chennai 600068 (India); Anbalagan, G., E-mail: [Department of Nuclear Physics, University of Madras, Chennai 600025 (India)


    A neoteric organic third order nonlinear optical material 8-hydroxyquinolinium 2-chloro-5-nitrobenzoate dihydrate (8HQ2C5N) was grown by slow cooling technique using ethanol: water (1:1) mixed solvent. The calculated low value of average etch pit solidity (4.12 × 10{sup 3} cm{sup −2}) indicated that the title crystal contain less defects. From the single crystal X-ray diffraction data, it was endowed that 8HQ2C5N crystal belongs to the monoclinic system with centrosymmetric space group P2{sub 1}/c and the cell parameters values, a = 9.6546 (4) Ǻ, b = 7.1637(3) Ǻ, c = 24.3606 (12) Ǻ, α = γ = 90°, β = 92.458(2)° and volume = 1683.29(13) Ǻ{sup 3}. The FT-IR and FT-Raman spectrum were used to affirm the functional group of the title compound. The chemical structure of 8HQ2C5N was scrutinized by {sup 13}C and {sup 1}H NMR spectral analysis and thermal stability through the differential scanning calorimetry study. Using optical studies the lower cut-off wavelength and optical band gap of 8HQ2C5N were found to be 364 nm and 3.17 eV respectively. Using the single oscillator model suggested by Wemple – Didomenico, the oscillator energy (E{sub o}), the dispersion energy (E{sub d}) and static dielectric constant (ε{sub o}) were estimated. The third-order susceptibility were determined as Im χ{sup (3)} = 2.51 × 10{sup −5} esu and Re χ{sup (3)} = 4.46 × 10{sup −7} esu. The theoretical third-order nonlinear optical susceptibility χ{sup (3)} was calculated and the results were compared with experimental value. Photoluminescence spectrum of 8HQ2C5N crystal showed the yellow emission. The crystal had the single shot laser damage threshold of 5.562 GW/cm{sup 2}. Microhardness measurement showed that 8HQ2C5N belongs to a soft material category. - Highlights: • A new organic single crystals were grown and the crystal structure was reported. • Crystal possess, good transmittance, thermal and mechanical stability. • Single shot LDT value is found to be

  11. Efficient propagation of TM polarized light in photonic crystal components exhibiting band gaps for TE polarized light

    DEFF Research Database (Denmark)

    Borel, Peter Ingo; Frandsen, Lars Hagedorn; Thorhauge, Morten;


    We have investigated the properties of TM polarized light in planar photonic crystal waveguide structures, which exhibit photonic band gaps for TE polarized light. Straight and bent photonic crystal waveguides and couplers have been fabricated in silicon-on-insulator material and modelled using a 3...... in a simple photonic crystal coupler with a size of ~ 20 m × 20 m. These promising features may open for the realization of ultra-compact photonic crystal components, which are easily integrated in optical communication networks....

  12. Space manufacturing in an automated crystal growth facility (United States)

    Quinn, Alberta W.; Herrmann, Melody C.; Nelson, Pamela J.


    An account is given of a Space Station Freedom-based robotic laboratory system for crystal growth experiments; the robot must interface with both the experimental apparatus and such human input as may be required for control and display. The goal of the system is the simultaneous growth of several hundred protein crystals in microgravity. The robot possesses six degrees-of-freedom, allowing it to efficiently manipulate the cultured crystals as well as their respective growth cells; the crystals produced are expected to be of sufficiently high quality for complete structural determination on the basis of XRD.

  13. Low-temperature (75 °C) solid-state reaction enhanced by less-crystallized nanoporous PbI2 films for efficient CH3NH3PbI3 perovskite solar cells (United States)

    Zheng, Huifeng; Liu, Yangqiao; Sun, Jing


    Organohalide perovskite films are usually prepared with the solid-state reaction at a high temperature ≥100 °C, which causes the increase of non-radiative defects and decomposition of perovskite films. Here, we demonstrate it's feasible to prepare high-quality perovskite films with the solid-state reaction method even at a temperature of 75 °C, when enhanced by less-crystallized nanoporous PbI2 (ln-PbI2) films. The replacement of compact PbI2 (c-PbI2) by ln-PbI2, results in a significant improvement of crystallinity of perovskite films, besides the elimination of remnant PbI2. As a result, ln-PbI2 based perovskite solar cells display much higher power conversion efficiency (PCE) and better stability. Moreover, annealing duration was found to be critical for high PCE and was optimized as 60 min. Finally, with the optimal process, the champion device displayed a PCE of 13.8% and the average PCE reached 10.1% with a satisfactory deviation. Furthermore, we found annealing at high temperature (140 °C) led to a lower PCE compared with that annealed at 75 °C, because non-radiative defects increased significantly during high-temperature annealing. This work may open up a promising avenue for preparing high-quality perovskite films with the low-temperature solid-state reaction method, which is desirable for real application.

  14. Scintillation properties of Lu sub 2 Si sub 2 O sub 7 :Ce sup 3 sup + , a fast and efficient scintillator crystal

    CERN Document Server

    Pidol, L; Viana, B; Ferrand, B; Dorenbos, P; Haas, J; Eijk, C W E; Virey, E


    Cerium doped lutetium pyrosilicate Lu sub 2 Si sub 2 O sub 7 :Ce sup 3 sup + (LPS), a new inorganic scintillator, displays particularly promising performance. This material can be readily pulled from the melt. A high light output (average value: 26 300 ph MeV sup - sup 1), a relatively good energy resolution (9%) and a fast decay time (38 ns) without afterglow make this new scintillator very attractive, in particular for medical imaging. Optical characterizations and scintillation properties of LPS:Ce large single crystals are presented, including timing properties and study of the scintillation yields as a function of incident energy.

  15. Microencapsulated Electrophoretic Films for Electronic Paper Displays (United States)

    Amundson, Karl


    Despite the dominance of liquid crystal displays, they do not perform some functions very well. While backlit liquid crystal displays can offer excellent color performance, they wash out in bright lighting and suffer from high power consumption. Reflective liquid crystal displays have limited brightness, making these devices challenging to read for long periods of time. Flexible liquid crystal displays are difficult to manufacture and keep stable. All of these attributes (long battery lifetime, bright reflective appearance, compatibility with flexible substrates) are traits that would be found in an ideal electronic paper display - an updateable substitute for paper that could be employed in electronic books, newspapers, and other applications. I will discuss technologies that are being developed for electronic-paper-like displays, and especially on particle-based technologies. A microencapsulated electrophoretic display technology is being developed at the E Ink corporation. This display film offers offer high brightness and an ink-on-paper appearance, compatibility with flexible substrates, and image stability that can lead to very low power consumption. I will present some of the physical and chemical challenges associated with making display films with high performance.

  16. Spectroscopic analysis and efficient diode-pumped 1.9 μm Tm3+-doped β'-Gd2(MoO4)3 crystal laser. (United States)

    Tang, Jianfeng; Chen, Yujin; Lin, Yanfu; Gong, Xinghong; Huang, Jianhua; Luo, Zundu; Huang, Yidong


    Tm3+-doped β'-Gd2(MoO4)3 single crystal was grown by the Czochralski method. Spectroscopic analysis was carried out along different polarizations. End-pumped by a quasi-cw diode laser at 795 nm in a plano-concave cavity, an average laser output power of 58 mW around 1.9 μm was achieved in a 0.93-mm-thick crystal when the output coupler transmission was 7.1%. The absorbed pump threshold was 8 mW and the slope efficiency of the laser was 57%. This crystal has smooth and broad gain curve around 1.9 μm, which shows that it is also a potential gain medium for tunable and short pulse lasers.

  17. High efficient 1.56 microm laser operation of Czochralski grown Er:Yb:Sr3Y2(BO3)4 crystal. (United States)

    Huang, Jianhua; Chen, Yujin; Lin, Yanfu; Gong, Xinghong; Luo, Zundu; Huang, Yidong


    An Er:Yb:Sr(3)Y(2)(BO(3))(4) crystal doped with 0.9 at.% Er(3+) and 18.6 at.% Yb(3+) ions was grown by the Czochralski method. End-pumped by diode laser at 970 nm in a hemispherical cavity, 1.3 W quasi-cw laser output around 1.56 microm was achieved in a 1.1-mm-thick Z-cut Er:Yb:Sr(3)Y(2)(BO(3))(4) crystal when the transmission of output coupler is 1.5%. The absorbed pump threshold and slop efficiency of the laser are 4.26 W and 20%, respectively. This crystal has flat and broad gain curve peaked around 1.56 microm, which shows that it is also a potential gain medium for tunable and short pulse lasers.

  18. Observation of high deflection efficiency and narrow energy loss distributions for 450 GeV protons channeled in a bent silicon crystal (United States)

    Møller, S. P.; Worm, T.; Clément, M.; Doble, N.; Elsener, K.; Gatignon, L.; Grafström, P.; Uggerhøj, E.; Hage-Ali, M.; Siffert, P.


    A 450 GeV proton beam has been deflected by various angles from 1 to 11 mrad using planar channeling in a (111) silicon crystal which was mechanically bent to achieve the desired beam deflection. High deflection efficiencies of up to 50% have been measured, in good agreement with present theoretical estimates. It is shown that bent crystals are also a unique tool for measurements of energy loss and straggling of channeled particles, without any influence from random particles: Selecting protons which are deflected by increasing angles corresponds to decreasing the transverse energy at the crystal entrance. With this technique energy loss and straggling was measured for protons channeled in the wide and narrow (111) planes in silicon for the first time.

  19. Simple and Efficient One-Pot Synthesis, Spectroscopic Characterization and Crystal Structure of Methyl 5-(4-Chlorobenzoyloxy-1-phenyl-1H-pyrazole-3-carboxylate

    Directory of Open Access Journals (Sweden)

    Imtiaz Khan


    Full Text Available A facile one-pot synthesis of methyl 5-(4-chlorobenzoyloxy-1-phenyl-1H-pyrazole-3-carboxylate (4 is described. The title compound was efficiently synthesized by the reaction of phenyl hydrazine, dimethyl acetylenedicarboxylate and 4-chlorobenzoyl chloride in dichloromethane under reflux in good yield. The structure of the target compound was deduced by modern spectroscopic and analytical techniques and unequivocally confirmed by a single crystal X-ray diffraction analysis. The crystal of the title compound belongs to orthorhombic system, space group P 21 21 21 with cell parameters a = 6.6491(3 Å, b = 7.9627(6 Å, c = 30.621(5 Å, α = β = γ = 90° and Z = 4. The crystal packing of the compound (4 is stabilized by an offset π-stacking between the planar benzoyl-substituted diazole moieties.

  20. Photoacoustic and dielectric spectroscopic studies of 4-dimethylamino-n-methyl-4-stilbazolium tosylate single crystal: An efficient terahertz emitter (United States)

    Manivannan, M.; Martin Britto Dhas, S. A.; Jose, M.


    Bulk terahertz emitting single crystal of 4-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST) was synthesized by condensation method and grown by slow solvent evaporation technique from methanol. The structure and cell parameters of the grown crystals were derived from single crystal and powder X-ray diffraction analyses and the optical properties of the crystal were analyzed by UV-Vis Spectrophotometer. The presence of functional groups was identified by FTIR and FT-Raman spectroscopic studies. We demonstrated that in DAST crystal, the thermal transport properties such as thermal conductivity, thermal diffusivity and thermal effusivity are better than several well recognized standard materials using photoacoustic spectrophotometer. The dielectric measurement was made as a function of frequency (1 Hz-35 MHz) at different temperatures (30-200 °C). The dielectric constant and dielectric loss were found to be strongly dependent on temperature and frequency of the applied electric field. The semicircle in the cole-cole plot showed the presence of dielectric relaxation in the crystal with its diameter representing the resistance of the crystal. The resistivity and ac conductivity were calculated from the measured dielectric data.

  1. Efficient cell surface display of Lip2 lipase using C-domains of glycosylphosphatidylinositol-anchored cell wall proteins of Yarrowia lipolytica. (United States)

    Yuzbasheva, Evgeniya Y; Yuzbashev, Tigran V; Laptev, Ivan A; Konstantinova, Tatiana K; Sineoky, Sergey P


    The cell surface display of enzymes is of great interest because of its simplified purification stage and the possibility for recycling in industrial processes. In this study, we have focused on the cell wall immobilization of Yarrowia lipolytica Lip2 protein--an enzyme that has a wide technological application. By genome analysis of Y. lipolytica in addition to already characterized Ylcwp1, we identified five putative open reading frames encoding glycosylphosphatidylinositol-anchored proteins. Lip2 translation fusion with the carboxyl termini of these proteins revealed that all proteins were capable of immobilizing lipase in active form on the cell surface. The highest level of cell-bound lipase activity was achieved using C-domains encoded by YlCWP1, YlCWP3 (YALI0D27214g) and YlCWP6 (YALI0F18282g) comprising 16,173 ± 1,800, 18,785 ± 1,130 and 17,700 ± 2,101 U/g dry cells, respectively. To the best of our knowledge, these results significantly exceed the highest cell-bound lipase activity previously reported for engineered Saccharomyces cerevisiae and Pichia pastoris strains. Furthermore, the lyophilized biomass retained the activity and was robust to collecting/resuspending procedures. Nevertheless, in most cases, a substantial amount of lipase activity was also found in the growth medium. Further work will be necessary to better understand the nature of this phenomenon.

  2. Augmenting digital displays with computation (United States)

    Liu, Jing

    As we inevitably step deeper and deeper into a world connected via the Internet, more and more information will be exchanged digitally. Displays are the interface between digital information and each individual. Naturally, one fundamental goal of displays is to reproduce information as realistically as possible since humans still care a lot about what happens in the real world. Human eyes are the receiving end of such information exchange; therefore it is impossible to study displays without studying the human visual system. In fact, the design of displays is rather closely coupled with what human eyes are capable of perceiving. For example, we are less interested in building displays that emit light in the invisible spectrum. This dissertation explores how we can augment displays with computation, which takes both display hardware and the human visual system into consideration. Four novel projects on display technologies are included in this dissertation: First, we propose a software-based approach to driving multiview autostereoscopic displays. Our display algorithm can dynamically assign views to hardware display zones based on multiple observers' current head positions, substantially reducing crosstalk and stereo inversion. Second, we present a dense projector array that creates a seamless 3D viewing experience for multiple viewers. We smoothly interpolate the set of viewer heights and distances on a per-vertex basis across the arrays field of view, reducing image distortion, crosstalk, and artifacts from tracking errors. Third, we propose a method for high dynamic range display calibration that takes into account the variation of the chrominance error over luminance. We propose a data structure for enabling efficient representation and querying of the calibration function, which also allows user-guided balancing between memory consumption and the amount of computation. Fourth, we present user studies that demonstrate that the ˜ 60 Hz critical flicker fusion

  3. Diagnostic performance of detecting breast cancer on computed radiographic (CR) mammograms: comparison of hard copy film, 3-megapixel liquid-crystal-display (LCD) monitor and 5-megapixel LCD monitor. (United States)

    Yamada, Takayuki; Suzuki, Akihiko; Uchiyama, Nachiko; Ohuchi, Noriaki; Takahashi, Shoki


    The purpose was to compare observer performance in the detection of breast cancer using hard-copy film, and 3-megapixel (3-MP) and 5-megapixel (5-MP) liquid crystal display (LCD) monitors in a simulated screening setting. We amassed 100 sample sets, including 32 patients with surgically proven breast cancer (masses present, N = 12; microcalcifications, N = 10; other types, N = 10) and 68 normal controls. All the mammograms were obtained using computed radiography (CR; sampling pitch of 50 mum). Twelve mammographers independently assessed CR mammograms presented in random order for hard-copy and soft-copy reading at minimal 4-week intervals. Observers rated the images on seven-point (1 to 7) and continuous (0 to 100) malignancy scales. Receiver-operating-characteristics analysis was performed, and the average area under the curve (AUC) was calculated for each modality. The jackknife method with the Bonferroni correction was applied to multireader/multicase analysis. The average AUC values for the 3-MP LCD, 5-MP LCD, and hard-copy film were 0.954, 0.947, and 0.956 on the seven-point scale and 0.943, 0.923, and 0.944 on the continuous scale, respectively. There were no significant differences among the three modalities on either scale. Soft-copy reading using 3-MP and 5-MP LCDs is comparable to hard-copy reading for detecting breast cancer.

  4. Influence of MTN-LCD Parameters to Liquid Crystal on Silicon Display Device%混合扭曲向列相模式的液晶盒参数对硅基液晶显示器的影响

    Institute of Scientific and Technical Information of China (English)

    姜丽; 范伟; 代永平; 张志东


    Mixed mode twisted nematic (MTN) characterized by excellent color dispersion effect and low driving voltage is used in liquid crystal on silicon (LCOS).Based on MTN mode, the influence of LCD parameters on LCOS display were simulated in this paper, such as the elastic constants, dielectric constant, pretilt angle and cell gap, et al.The simulation results can provide scientific basis for the research of LCOS.%90°混合扭曲向列相液晶(MTN)模式因其良好的关态色散特性、低驱动电压而被应用于小型或者微型硅基液晶显示器(LCOS).针对MTN模式,模拟研究了液晶弹性常数、介电各向异性、预倾角以及盒厚变化对显示效果的影响,研究结果为硅基液晶显示器的开发提供了一定的理论依据.

  5. A Highly Efficient Human Pluripotent Stem Cell Microglia Model Displays a Neuronal-Co-culture-Specific Expression Profile and Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Walther Haenseler


    Full Text Available Microglia are increasingly implicated in brain pathology, particularly neurodegenerative disease, with many genes implicated in Alzheimer's, Parkinson's, and motor neuron disease expressed in microglia. There is, therefore, a need for authentic, efficient in vitro models to study human microglial pathological mechanisms. Microglia originate from the yolk sac as MYB-independent macrophages, migrating into the developing brain to complete differentiation. Here, we recapitulate microglial ontogeny by highly efficient differentiation of embryonic MYB-independent iPSC-derived macrophages then co-culture them with iPSC-derived cortical neurons. Co-cultures retain neuronal maturity and functionality for many weeks. Co-culture microglia express key microglia-specific markers and neurodegenerative disease-relevant genes, develop highly dynamic ramifications, and are phagocytic. Upon activation they become more ameboid, releasing multiple microglia-relevant cytokines. Importantly, co-culture microglia downregulate pathogen-response pathways, upregulate homeostatic function pathways, and promote a more anti-inflammatory and pro-remodeling cytokine response than corresponding monocultures, demonstrating that co-cultures are preferable for modeling authentic microglial physiology.

  6. Synthesis, crystal growth, thermal studies and scaled quantum chemical studies of structural and vibrational spectra of the highly efficient organic NLO crystal: 1-(4-Aminophenyl)-3-(3,4-dimethoxyphenyl)-prop-2-en-1-one

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Lynnette [Department of Physics, Bishop Moore College, Mavelikara, Alappuzha 690110, Kerala (India); Department of Physics, C.M.S College, Kottayam 686001, Kerala (India); Sajan, D., E-mail: [Department of Physics, Bishop Moore College, Mavelikara, Alappuzha 690110, Kerala (India); Shettigar, Venkataraya [Department of Physics, Gokhale Centenary College, Ankola 581 314, Karnataka (India); Chaitanya, K. [Key Laboratory of Soft Chemistry and Functional Materials of MOE, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Misra, Neeraj [Department of Physics, University of Lucknow, Lucknow 22607 (India); Sundius, Tom [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland); Němec, I. [Charles University in Prague, Faculty of Science, Department of Inorganic Chemistry, Hlavova 8, 128 40 Prague 2 (Czech Republic)


    A new chalcone derivative, 1-(4-aminophenyl)-3-(3,4-dimethoxyphenyl)-prop-2-en-1-one (DMAC) was synthesized and single crystals were grown by slow evaporation technique. The FT-Raman and FT-IR spectra of the sample were recorded in the region 3700–100 cm{sup −1} and 4000–400 cm{sup −1}, respectively. The spectra were interpreted with the aid of normal coordinate analysis following structure optimizations and force field calculations based on density functional theory (DFT) at the B3LYP/6-311+G(d,p) level of theory. Normal coordinate calculations were performed using the DFT force field, corrected by a recommended set of scaling factors, yielding fairly good agreement between the observed and calculated wavenumbers. DMAC is thermally stable up to 220.0 °C and optically transparent in the visible region. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecule has been obtained by mapping electron density isosurface with electrostatic potential surfaces (ESP). The SHG efficiency of DMAC is observed to be 10 times that of standard urea crystal of identical particle size. - Highlights: • A chalcone derivative, DMAC has been synthesized and crystals are grown. • FT-IR and FT-Raman spectra, thermogravimetric and UV–Vis studies were carried out. • SHG effect from a centrosymmetric crystal has been reported.

  7. Liquid Crystal Materials for Matrix Displays. (United States)


    TBATPB-doped MBBA, which is shown as a reference curve in Figure 1. More complete data on the scattering angles of HRL-26N3 -26N4, and - 25N2 are shown...D/T is more favorable at 20 V than at 15 V dc,Don since at higher voltage TD increases, and T decreases. For example,on at 20 V and 64*C the TD /Ton...Figure 9) changes with temperature. In the lower temperature range the TD and TON decrease with increasing temperature in the same manner as n

  8. Characterising laser beams with liquid crystal displays

    CSIR Research Space (South Africa)

    Dudley, Angela L


    Full Text Available We show how one can determine the various properties of light, from the modal content of laser beams to decoding the information stored in optical fields carrying orbital angular momentum, by performing a modal decomposition. Although the modal...

  9. Addressing techniques of liquid crystal displays

    CERN Document Server

    Ruckmongathan, Temkar N


    Unique reference source that can be used from the beginning to end of a design project to aid choosing an appropriate LCD addressing technique for a given application This book will be aimed at design engineers who are likely to embed LCD drivers and controllers in many systems including systems on chip. Such designers face the challenge of making the right choice of an addressing technique that will serve them with best performance at minimal cost and complexity. Readers will be able to learn about various methods available for driving matrix LCDs and the comparisons at the end of each chap

  10. Near isohydric grapevine cultivar displays higher photosynthetic efficiency and photorespiration rates under drought stress as compared with near anisohydric grapevine cultivar. (United States)

    Hochberg, Uri; Degu, Asfaw; Fait, Aaron; Rachmilevitch, Shimon


    Drought stress is known to limit photosynthesis rates and to inflict photo-oxidative damage in grapevines. Grapevines, which are considered drought-tolerant plants, are characterized by diverse hydraulic and photosynthetic behaviors, depending on the cultivar. This research compared the photosynthesis and the photorespiration of Cabernet Sauvignon (Cs) (isohydric) and Shiraz (anisohydric) in an attempt to acquire a wider perspective on the iso/anisohydric phenomenon and its implications. Shiraz and Cs were subjected to terminal drought in the greenhouse. Soil water content (θ), leaf water potential (Ψl ) and stomata conductance (gs ) were measured to determine the cultivars' hydraulic behavior. Gas exchange and fluorometry measurements were taken at 21 and 2% O2 to acquire photosynthesis and photorespiration characteristics. Cs was found to behave in a near isohydric manner whereas Shiraz behaved in a near anisohydric manner. Compared to Shiraz, the reduced stomata conductance values of Cs were accompanied by higher water use efficiency and photorespiration rates, as well as photosystem II photochemical potential (Fv /Fm ). As compared with Shiraz, Cs compensated for lower stomata conductance by higher photosynthesis and photorespiration. These two processes contributed to higher electron flow rates that might have a role in photoinhibition avoidance, which was observed in the stability of Fv /Fm under drought stress.

  11. Highly efficient dual-wavelength mid-infrared CW Laser in diode end-pumped Er:SrF2 single crystals (United States)

    Ma, Weiwei; Qian, Xiaobo; Wang, Jingya; Liu, Jingjing; Fan, Xiuwei; Liu, Jie; Su, Liangbi; Xu, Jun


    The spectral properties and laser performance of Er:SrF2 single crystals were investigated and compared with Er:CaF2. Er:SrF2 crystals have larger absorption cross-sections at the pumping wavelength, larger mid-infrared stimulated emission cross-sections and much longer fluorescence lifetimes of the upper laser level (Er3+:4I11/2 level) than those of Er:CaF2 crystals. Dual-wavelength continuous-wave (CW) lasers around 2.8 μm were demonstrated in both 4at.% and 10at.% Er:SrF2 single crystals under 972 nm laser diode (LD) end pumping. The laser wavelengths are 2789.3 nm and 2791.8 nm in the former, and 2786.4 nm and 2790.7 nm in the latter, respectively. The best laser performance has been demonstrated in lightly doped 4at.% Er:SrF2 with a low threshold of 0.100 W, a high slope efficiency of 22.0%, an maximum output power of 0.483 W.

  12. Highly Efficient LiYF4:Yb(3+), Er(3+) Upconversion Single Crystal under Solar Cell Spectrum Excitation and Photovoltaic Application. (United States)

    Chen, Xu; Xu, Wen; Song, Hongwei; Chen, Cong; Xia, Haiping; Zhu, Yongsheng; Zhou, Donglei; Cui, Shaobo; Dai, Qilin; Zhang, Jiazhong


    Luminescent upconversion is a promising way to harvest near-infrared (NIR) sunlight and transforms it into visible light that can be directly absorbed by active materials of solar cells and improve their power conversion efficiency (PCE). However, it is still a great challenge to effectively improve the PCE of solar cells with the assistance of upconversion. In this work, we demonstrate the application of the transparent LiYF4:Yb(3+), Er(3+) single crystal as an independent luminescent upconverter to improve the PCE of perovskite solar cells. The LiYF4:Yb(3+), Er(3+) single crystal is prepared by an improved Bridgman method, and its internal quantum efficiency approached to 5.72% under 6.2 W cm(-2) 980 nm excitation. The power-dependent upconversion luminescence indicated that under the excitation of simulated sunlight the (4)F(9/2)-(4)I(15/2) red emission originally results from the cooperation of a 1540 nm photon and a 980 nm photon. Furthermore, when the single crystal is placed in front of the perovskite solar cells, the PCE is enhanced by 7.9% under the irradiation of simulated sunlight by 7-8 solar constants. This work implies the upconverter not only can serve as proof of principle for improving PCE of solar cells but also is helpful to practical application.

  13. The energy coupling efficiency of multi-wavelength laser pulses to damage initiating defects in DKDP nonlinear crystals

    Energy Technology Data Exchange (ETDEWEB)

    DeMange, P; Negres, R A; Rubenchik, A M; Radousky, H B; Feit, M D; Demos, S G


    The bulk damage performance of potassium dihydrogen phosphate crystals under simultaneous exposure to 1064-, 532-, and 355-nm nanosecond-laser pulses is investigated in order to probe the laser-induced defect reactions leading to damage initiation during frequency conversion. The results provide insight into the mechanisms governing the behavior of the damage initiating defects under exposure to high power laser light. In addition, it is suggested that the damage performance can be directly related to and predicted from the damage behavior of the crystal at each wavelength separately.

  14. Organic Crystals with Near-Infrared Amplified Spontaneous Emissions Based on 2'-Hydroxychalcone Derivatives: Subtle Structure Modification but Great Property Change. (United States)

    Cheng, Xiao; Wang, Kai; Huang, Shuo; Zhang, Houyu; Zhang, Hongyu; Wang, Yue


    A series of highly efficient deep red to near-infrared (NIR) emissive organic crystals 1-3 based on the structurally simple 2'-hydroxychalcone derivatives were synthesized through a simple one-step condensation reaction. Crystal 1 displays the highest quantum yield (Φf) of 0.32 among the reported organic single crystals with an emission maximum (λem) over 710 nm. Comparison between the bright emissive crystals 1-3 and the nearly nonluminous compounds 4-7 clearly gives evidence that a subtle structure modification can arouse great property changes, which is instructive in designing new high-efficiency organic luminescent materials. Notably, crystals 1-3 exhibit amplified spontaneous emissions (ASE) with extremely low thresholds. Thus, organic deep red to NIR emissive crystals with very high Φf have been obtained and are found to display the first example of NIR fluorescent crystal ASE.

  15. Efficient monitoring of blood-stage infection in a malaria rodent model by the rotating-crystal magneto-optical method

    CERN Document Server

    Orban, Agnes; Albuquerque, Inês S; Butykai, Adam; Kezsmarki, Istvan; Hänscheid, Thomas


    Global research efforts have been focused on the simultaneous improvement of the efficiency and sensitivity of malaria diagnosis in resource-limited settings and for the active case detection of asymptomatic infections. A recently developed magneto-optical (MO) method allows the high-sensitivity detection of malaria pigment (hemozoin) crystals in blood via their magnetically induced rotational motion. The evaluation of the method using synthetic $\\beta$-hematin crystals and P. falciparum in vitro cultures implies its potential for in-field diagnosis. Here, we study the performance of the method in monitoring the in vivo onset and progression of the blood stage infection using a malaria mouse model. We found that the MO method can detect the first generation of intraerythrocytic parasites at the ring stage 61-66 hours after sporozoite injection demonstrating better sensitivity than light microscopy and flow cytometry. MO measurements performed after treatment of severe P. berghei infections show that the clear...

  16. Detection of masses and microcalcifications of breast cancer on digital mammograms: comparison among hard-copy film, 3-megapixel liquid crystal display (LCD) monitors and 5-megapixel LCD monitors: an observer performance study. (United States)

    Kamitani, Takeshi; Yabuuchi, Hidetake; Soeda, Hiroyasu; Matsuo, Yoshio; Okafuji, Takashi; Sakai, Shuji; Furuya, Akio; Hatakenaka, Masamitsu; Ishii, Nobuhide; Honda, Hiroshi


    The purpose of the study was to compare observer performance in the detection of masses and microcalcifications of breast cancer among hard-copy reading and soft-copy readings using 3-megapixel (3M) and 5-megapixel (5M) liquid crystal display (LCD) monitors. For the microcalcification detection test, we prepared 100 mammograms: 40 surgically verified cancer cases and 60 normal cases. For the mass detection test, we prepared 100 mammograms: 50 cancer cases and 50 normal cases. After six readers assessed both microcalcifications and masses set for each modality, receiver operating characteristic (ROC) analysis was performed. The average A(z)s for mass detection using a hard copy and 3M and 5M LCD monitors were 0.923, 0.927 and 0.920, respectively; there were no significant differences. The average A(z) for microcalcification detection using hard copy, 3M and 5M LCD monitors was 0.977, 0.954 and 0.972, respectively. There were no significant differences, but the P-values between the hard copy and 3M LCD monitor and that between the 3M and 5M LCD monitor were 0.08 and 0.09, respectively. In conclusion, the observer performances for detecting masses of breast cancers were comparable among the hard copy and two LCD monitors; however, soft-copy reading with a 3M LCD monitor showed slightly lower observer performance for detecting microcalcifications of breast cancers than hard-copy or 5M LCD monitor reading.

  17. Heath monitoring of a glass transfer robot in the mass production line of liquid crystal display using abnormal operating sounds based on wavelet packet transform and artificial neural network (United States)

    Kim, Eui-Youl; Lee, Young-Joon; Lee, Sang-Kwon


    This paper presents the fault detect method of a moving transfer robot in the mass production line of liquid crystal display (LCD) manufacturers based on the wavelet packet transform (WPT) for feature extraction and the artificial neural network (ANN) for fault classification. Most of fault detection methods in a mechanical system have been researched based on the vibration signal. Unlike the existing methodologies, this study aims to minimize the uncertainty of a field engineer's decision making process for determining whether a fault is present or not based on the human auditory perception by developing a fault diagnosis system that uses the abnormal operating sound radiated from a moving transfer robot as a source signal. Abnormal operating sound radiated from a moving transfer robot has been used for this work instead of other source signals such as vibration, acoustic emission, electrical signal, etc. Its advantage as a source signal makes it possible to monitor the status of multiple faults by using only a microphone despite a relatively low sensitivity. In the application of ANN, since it is important to minimize the error of trained ANN in terms of the accuracy of fault diagnosis logic, in the paper, the number of input and target data samples was increased through a regeneration process based on statistical properties, and then the uncorrelated nodes in the input vector were also removed to improve the orthogonality of the input vector based on the entropy based feature selection method. Consequently, it can be concluded that the abnormal operating sound is sufficiently useful as a source signal for the fault diagnosis of mechanical components as well as other source signals.

  18. Robustness of average Stokes polarimetry characterization of digitally addressed parallel-aligned LCoS displays


    Martínez Guardiola, Francisco Javier; Márquez Ruiz, Andrés; Gallego Rico, Sergi; Ortuño Sánchez, Manuel; Francés Monllor, Jorge; Beléndez Vázquez, Augusto; Pascual Villalobos, Inmaculada


    Parallel-aligned liquid crystal on silicon (PA-LCoS) displays have become the most attractive spatial light modulator device for a wide range of applications, due to their superior resolution and light efficiency, added to their phase-only capability. Recently we proposed a novel polarimetric method, based on Stokes polarimetry, enabling the characterization of their linear retardance and the magnitude of their associated phase fluctuations, if existent, as it happens in most of digital backp...

  19. Efficient picosecond traveling-wave Raman conversion in a SrWO4 crystal pumped by multi-Watt MOPA lasers at 1064 nm (United States)

    Farinello, Paolo; Pirzio, Federico; Zhang, Xingyu; Petrov, Valentin; Agnesi, Antonio


    Raman conversion with a 50-mm-long SrWO4 crystal in a single-pass, traveling-wave setup has been investigated in both purely steady-state and transient stimulated Raman scattering (SRS) regimes. For steady-state SRS experiment, we employed as a pump source a Q-Switched master oscillator power amplifier (MOPA) laser system at 1064 nm, delivering 325 μJ, 550-ps-long pulses with diffraction limited beam quality and high spectral purity. At 2-kHz repetition rate, we obtained up to 90 μJ pulse energy and 250 ps pulse duration at 1180 nm, with a conversion slope efficiency close to quantum limit. To approach the transient SRS regime, we pumped the same crystal with 16-ps-long pulses from a hybrid MOPA laser system based on a mode-locked Yb-fiber oscillator followed by a diode-pumped bulk Nd:YVO4 power amplifier. At the maximum incident pump average power of 3.75 W, we obtained 1.4 W at the first Stokes Raman-shifted wavelength of 1180 nm (37 % optical-to-optical conversion efficiency), with 15 ps pulse duration and 70 % conversion slope efficiency.

  20. Demonstration of omnidirectional photoluminescence (ODPL) spectroscopy for precise determination of internal quantum efficiency of radiation in GaN single crystals (United States)

    Kojima, Kazunobu; Ikeda, Hirotaka; Fujito, Kenji; Chichibu, Shigefusa F.


    For rating unambiguous performance of a light-emitting semiconductor material, determination of the absolute quantum efficiency (AQE) of radiation, which is basically a product of internal quantum efficiency (IQE) and light-extraction efficiency, is the most delightful way. Here, we propose the use of omnidirectional photoluminescence (ODPL) spectroscopy for quantifying AQE of the near-band-edge (NBE) emission, in order to evaluate bulk GaN crystals and wafers. When the measurement was carried out in the air, the AQE showed a continuous decrease most likely due to the formation of extrinsic nonradiative recombination channels at the surface by photo-pumping. However, such an influence was suppressed by measuring ODPL in an inert ambient such as nitrogen or in vacuum. Consequently, AQE was revealed to depend on the photo-pumping density. The increase in AQE of the NBE emission caused by the increase in the excess carrier concentration was significant, indicating gradual saturation of nonradiative recombination centers in the bulk of GaN. The highest AQE value (8.22%) ever reported for the NBE emission of GaN at room temperature, which corresponds to IQE of 70.9%, was eventually obtained from the GaN wafer grown by hydride vapor phase epitaxy on a GaN seed crystal manufactured by the acidic ammonothermal method, when the cw photo-pumping density was 66 W/cm2.

  1. Increase of brightness and transmission efficiency in flat panel display through serial synchronous scanning mode with double buffers%串行同步双缓冲扫描提高平板显示器的显示亮度和传送利用率

    Institute of Scientific and Technical Information of China (English)

    陈章进; 陈峰; 冉峰; 徐美华; 郑方


    This paper presents a serial synchronous scanning mode in flat panel display(FPD)by adding a latch buffer between the seriaiizer and the driving buffer.Comparing with conventional techniques,the proposed structure can efficiently reduce the brightness loss and improve the transmission performance.Theoretical analysis and experimental results show that the ratio between the lightest weight display time and the relative transmission time is a tradeoff between brightness loss and transmission efficiency.

  2. Do LCDs have a chance to keep a leading position on flat panel display market? (United States)

    Zielinski, Jerzy; Olifierczuk, Marek


    A lot of significant discoveries and inventions in the field of technology of displays were made in the latter part of the twentieth century. Apart from well-known CRT, the plasma-, luminescence- and liquid crystal-displays are commercially available. One can notice that a leading position on that flat panel displays market belong to LCD. But the progress in Organic LED materials and devices is impressive. Threshold voltage for light emission have fallen from several thousands V to just 2 - 3 V for today's OLEDs (polymer and small molecule). Luminous efficiency has increased from 0,01 to more than 10 lm/W. These improvements have brought PLED technology to the point where serious consideration is being given to OLED graphic and video display product. The question given some years ago by Dr. M. E. Becker, [Display Metrology and Systems]: " the current OLED enthusiasm justified because OLED displays feature significant improvements in visual and ergonomic performance, and because they are much cheaper to manufacture; Or it is just another hope for those who missed the LCD train?...," is trite. During SID Conference in Baltimore in 2003 two companies claiming to have built the largest organic LED. International Display Technology demonstrated a 20 inch display driven by "super amorphous silicon" technology; Sony showed off its 24 inch screen, which consists of a 2x2 tiled array of OLED displays. The presented work will be oriented towards specifying the characteristic features of liquid crystal and electro luminescence organic compounds which make these groups of displays so attractive and prospective among other imagery systems devices existing nowadays.

  3. Efficient conversion from infrared to red light by cascaded nonlinear optical processes using an aperiodically poled lithium niobate crystal

    Directory of Open Access Journals (Sweden)

    Juan Eduardo González


    Full Text Available We present a scheme for conversion of pulsed light from the infrared to the red spectral region, using an aperiodically poled ferroelectric crystal within a resonant cavity in which two cascaded nonlinear optical processes occur when pumped with a pulsed Nd:YAG laser. This device emits 9 ns pulses of over 1 mJ at 710 nm and is a viable source for future biomedical applications.

  4. Microwave-assisted self-doping of TiO2 photonic crystals for efficient photoelectrochemical water splitting

    KAUST Repository

    Zhang, Zhonghai


    In this article, we report that the combination of microwave heating and ethylene glycol, a mild reducing agent, can induce Ti3+ self-doping in TiO2. A hierarchical TiO2 nanotube array with the top layer serving as TiO2 photonic crystals (TiO2 NTPCs) was selected as the base photoelectrode. The self-doped TiO2 NTPCs demonstrated a 10-fold increase in visible-light photocurrent density compared to the nondoped one, and the optimized saturation photocurrent density under simulated AM 1.5G illumination was identified to be 2.5 mA cm-2 at 1.23 V versus reversible hydrogen electrode, which is comparable to the highest values ever reported for TiO2-based photoelectrodes. The significant enhancement of photoelectrochemical performance can be ascribed to the rational coupling of morphological and electronic features of the self-doped TiO 2 NTPCs: (1) the periodically morphological structure of the photonic crystal layer traps broadband visible light, (2) the electronic interband state induced from self-doping of Ti3+ can be excited in the visible-light region, and (3) the captured light by the photonic crystal layer is absorbed by the self-doped interbands. © 2013 American Chemical Society.

  5. Display system analysis with critical polarization elements in a non-sequential ray tracing environment (United States)

    Herlocker, J. A.; Jiang, J.; Garcia, K. J.


    Common digital display systems have evolved into sophisticated optical devices. The rapid market growth in liquid crystal displays makes the simulation of full systems attractive, promoting virtual prototyping with decreased development times and improved manufacturability. Realistic simulation using commercial non-sequential ray tracing tools has been instrumental in this process, but the need to accurately model polarization devices has become critical in many designs. As display systems seek more efficient use of light and more accurate color representation, the proper simulation of polarization devices with large acceptance angles is essential. This paper examines non-uniform polarization effects in the simulation of modern display devices using realistic polarizer and retarder models in the ASAP® non-sequential ray-tracing environment.

  6. Invisible Display in Aluminum

    DEFF Research Database (Denmark)

    Prichystal, Jan Phuklin; Hansen, Hans Nørgaard; Bladt, Henrik Henriksen


    for an integrated display in a metal surface is often ruled by design and functionality of a product. The integration of displays in metal surfaces requires metal removal in order to clear the area of the display to some extent. The idea behind an invisible display in Aluminum concerns the processing of a metal...

  7. 晶体角度跟随三倍频效率控制技术%Third harmonic efficiency control with crystal angular following

    Institute of Scientific and Technical Information of China (English)

    赵润昌; 李平; 李海; 张军伟; 耿远超; 李志军; 粟敬钦


    Based on the analytical solution of the dependence of phase matching angle on the crystal temperature,we illus-trate the thermo-optic physical mechanism of temperature influence on the frequency conversion.The thermal sensitivity of the doubler and tripler crystals are numerically simulated respectively.Due to such sensitivity discrepancy among various crystals,the phase matching angle curve regarding the crystal temperature variation in our laser facility is obtained in experiment.The influ-ence of PM angular detune on frequency conversion is theoretically analyzed under different input intensities,which is demonstra-ted by the conversion efficiency decline induced by temperature variation.According to the thermal sensitivity parameter obtained in experiments,we compensate the conversion efficiency with the crystal angle following,resulting in stable output of third har-monic energy.%基于推导的倍频晶体匹配角与温度关系的理论分析,揭示了温度对频率转换过程影响的热光物理机制。数值模拟了频率转换过程中二倍频与三倍频晶体的匹配角热敏感性。由于不同晶体材料热敏感性的差异性,实验获得了激光装置中所用晶体材料的匹配角随温度变化的关系曲线。理论分析了不同输入功率密度情况下匹配角失谐对三倍频过程的影响,并在线验证了温度变化导致匹配角失谐,进而引起三倍频转换效率的下降。根据实验获得的晶体匹配角的热敏感性参数,提出利用晶体角度跟随方法进行三倍频转换效率补偿,实现了三倍频能量的稳定输出。

  8. Modeling magnetic photonic crystals with lossy ferrites using an efficient complex envelope alternating-direction-implicit finite-difference time-domain method. (United States)

    Singh, Gurpreet; Tan, Eng Leong; Chen, Zhi Ning


    In this Letter, we present an efficient complex-envelope alternating-direction-implicit finite-difference time-domain (CE-ADI-FDTD) method for the transient analysis of magnetic photonic crystals with lossy ferrites. The proposed CE-ADI-FDTD method is generally formulated for a saturated ferrite with anisotropic permittivity tensor and ferrite loss. Auxiliary differential equations for modeling saturated ferrite and Maxwell's curl equations are first cast into a first-order differential system in a CE form. Then, by using an efficient ADI splitting formulas, the proposed CE-ADI-FDTD method is attained in a very concise form with few and simple right-hand side terms. The performance of the proposed method is validated and compared with the explicit FDTD method.

  9. Efficient high-power generation of visible and mid-infrared light by degenerate four-wave-mixing in a large-mode-area photonic-crystal fiber. (United States)

    Nodop, D; Jauregui, C; Schimpf, D; Limpert, J; Tünnermann, A


    An efficient and simple approach for converting pulsed near-IR laser radiation into visible and mid-IR light by exploiting degenerate four-wave-mixing in an endlessly single-mode, large-mode-area photonic-crystal fiber is presented. Coupling a 1 MHz, 200 ps, 8 W average power pulsed source emitting at 1064 nm into this fiber results in average powers of 3 W at 673 nm signal wavelength and of 450 mW at 2539 nm idler wavelength, respectively. The excellent pulse energy conversion efficiencies of 35% for the signal and 6% for the idler wavelength are due to the unique combination of characteristics of this type of fiber.

  10. Microjoule sub-10 fs VUV pulse generation by MW pump pulses using highly efficient chirped four-wave mixing in hollow-core photonic crystal fibers (United States)

    Im, Song-Jin


    We theoretically study chirped four-wave mixing for VUV pulse generation in hollow-core photonic crystal fibers. We predict the generation of sub-10 fs VUV pulses with energy of up to hundreds of µJ by broad-band chirped idler pulses at 830 nm and MW pump pulses with narrow-band at 277 nm. The MW pump could be desirable to reduce the complexity of the laser system or use a high repetition rate laser system. The energy conversion efficiency from pump pulse to VUV pulse reaches to 30% . This generation can be realized in a kagome-lattice hollow-core PCF filled with noble gas of high pressure with core diameter less than 40 µm, which would enable technically simple or highly efficient coupling to the fundamental mode of the fiber.

  11. Micro-joule sub-10-fs VUV pulse generation by MW pump pulse using highly efficient chirped-four-wave mixing in hollow-core photonic crystal fibers

    CERN Document Server

    Im, Song-Jin


    We theoretically study chirped four-wave mixing for VUV pulse generation in hollow-core photonic crystal fibers. We predict the generation of sub-10-fs VUV pulses with energy of up to hundreds of microjoule by broad-band chirped idler pulses at 830 nm and MW pump pulses with narrow-band at 277 nm. MW pump could be desirable to reduce the complexity of the laser system or use a high repetition rate-laser system. The energy conversion efficiency from pump pulse to VUV pulse reaches to 30%. This generation can be realized in kagome-lattice hollow-core PCF filled with noble gas of high pressure with core-diameter less than 40 micrometers which would enable technically simple or highly efficient coupling to fundamental mode of the fiber.

  12. A novel dinuclear schiff base copper complex as an efficient and cost effective catalyst for oxidation of alcohol: Synthesis, crystal structure and theoretical studies

    Indian Academy of Sciences (India)

    Atena Naeimi; Samira Saeednia; Mehdi Yoosefian; Hadi Amiri Rudbari; Viviana Mollica Nardo


    An environmentally friendly protocol is described for an economic, practical laboratory-scale oxidation of primary and secondary alcohols to aldehydes and ketones, using a bis-chloro-bridged binuclear Cu(II) complex [(HL)Cu(2-Cl)2Cu(HL)]*1.5 CH3OH as catalyst. The catalyst was prepared in situ from commercially available reagents and is characterized by single crystal X-ray analysis, FT-IR, UV-visible spectra, mass spectrometry, and powder x-ray diffraction (PXRD). The geometry of the complex has been optimized using the B3LYP level of theory confirming the experimental data. Our results demonstrated well the efficiency, selectivity and stability of this new catalyst in the oxidation of alcohols in ethanol and tert-butyl hydroperoxide (tBuOOH) as a green solvent and oxidant, respectively. Turnover number and reusability have proven the high efficiency and relative stability of the catalyst.

  13. MyCrystals - a simple visual data management program for laboratory-scale crystallization experiments

    DEFF Research Database (Denmark)

    Løvgreen, Monika Nøhr; Løvgreen, Mikkel; Christensen, Hans Erik Mølager


    MyCrystals is designed as a user-friendly program to display crystal images and list crystallization conditions. The crystallization conditions entry fields can be customized to suit the experiments. MyCrystals is also able to sort the images by the entered crystallization conditions, which...

  14. Doping effect of L-cystine on structural, UV-visible, SHG efficiency, third order nonlinear optical, laser damage threshold and surface properties of cadmium thiourea acetate single crystal (United States)

    Azhar, S. M.; Anis, Mohd; Hussaini, S. S.; Kalainathan, S.; Shirsat, M. D.; Rabbani, G.


    The present article is focused to investigate the influence of L-cystine (LC) on linear-non-linear optical and laser damage threshold of cadmium thiourea acetate (CTA) crystal. The structural parameters of pure and LC doped CTA crystals have been determined using the single crystal X-ray diffraction technique. The functional groups of grown crystals have been identified by means of fourier transform infrared (FT-IR) analysis. The UV-visible spectral analysis has been done in the range of 200-900 nm to ascertain the uplifting influence of LC on optical properties of CTA crystal. The second harmonic generation (SHG) efficiency of LC doped CTA crystal is found to be higher than CTA and KDP crystal. The Z-scan technique has been employed to determine the third order nonlinear optical (TONLO) nature of LC doped CTA crystal at 632.8 nm. The self focusing tendency confirmed the strong kerr lensing ability of LC doped CTA crystal. The TONLO susceptibility (χ3), refraction (n2) and absorption coefficient (β) has been calculated using the Z-scan data. The laser damage threshold of pure and LC doped CTA crystals has been measured using the Q-switched Nd:YAG laser and its is found to be in range of GW/cm2. The surface analysis has been done by means of etching studies.

  15. Low driving voltage and fast-response in-plane switching liquid crystal display%低驱动电压和快速响应的共面转换液晶显示器

    Institute of Scientific and Technical Information of China (English)

    王森; 孙玉宝


    In-plane switching liquid crystal displays (IPS-LCDs)are widely applied in TFT-LCD for its excellent viewing angle and outstanding ability of color reproduction.However,its development in high-end LCDs is limited by its slow response.A fast response IPS-LCD with protrusion electrode is proposed in this paper,and its optical characteristics is simulated by TechWiz software.With the pro-trusion electrode,the driving voltage of IPS-LCD is reduced by 2.3 V.Although the driving voltage is reduced,the electric field in the liquid crystal layer is changed due to the electrode on protrusion,so the rise response speed is improved.In addition,the protrusion structure reduces the effective cell gap of the LC layer,and the decay time is proportional to the square of the cell thickness,so the decay re-sponse speed is also obviously improved.The whole response speed is improved by approximately 38% in contrast with the conventional IPS-LCD.%共面转换液晶显示器(IPS-LCD)由于其优异的视角特性和色彩还原能力在 TFT-LCD 中得到了广泛应用,然而响应速度慢的缺点始终限制着其在高端液晶显示器中的发展.本文中提出一种凸起电极结构的共面转换液晶显示器,并采用 TechWiz 软件模拟了该结构的电光特性.与传统 IPS-LCD 相比,我们提出的新结构 IPS-LCD 的驱动电压降低了2.3 V.在响应时间方面,尽管驱动电压降低了,但是由于凸起电极改变液晶层中的电场状况,因此上升响应速度得到了一定提高.此外,凸起结构减小了液晶层的等效盒厚,因为下降时间正比于液晶盒厚的平方,所以下降响应速度也得到了明显提高,该结构的整体响应速度相比传统结构提高了大约38%.

  16. Design of an LED chip structure with an integrated two-dimensional photonic crystal to enhance the light-extraction efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Won-Sik; Park, Si-Hyun [Yeungnam University, Gyeongsan (Korea, Republic of)


    We numerically simulated the light-extraction efficiency of light-emitting diodes (LEDs) with an integrated two-dimensional photonic crystal (PC) structure on the top surface in order to enhance light extraction. We considered InGaN-based LED chips with a typical emission wavelength of λ{sub o} = 460 nm and an emission wavelength inside the LED chip of λ = λ{sub 0}/n{sub GaN} , where n{sub GaN} is the refractive index of GaN. We used positive (relief) and negative (intaglio) patterns for the PC structures with square arrangements. The pattern period (Λ), width (d), and height (h) of the PC structure were varied systematically in the PC-LEDs; then the light-extraction efficiency of each PC-LED was simulated numerically using a three-dimensional finite-difference time-domain method to optimize the PC structure in terms of light extraction. The PC LED with a square pillar pattern with Λ ∼ 1.4λ, d ∼ 0.75Λ, and h ∼ 0.75Λ had the maximum light-extraction efficiency for positive patterns while the cylindrical hole pattern with Λ ∼ 1.2λ, d ∼ 0.5Λ, and h ∼ 0.5Λ had the maximum light-extraction efficiency for negative patterns.

  17. A highly efficient CMOS nanoplasmonic crystal enhanced slow-wave thermal emitter improves infrared gas-sensing devices (United States)

    Pusch, Andreas; de Luca, Andrea; Oh, Sang S.; Wuestner, Sebastian; Roschuk, Tyler; Chen, Yiguo; Boual, Sophie; Ali, Zeeshan; Phillips, Chris C.; Hong, Minghui; Maier, Stefan A.; Udrea, Florin; Hopper, Richard H.; Hess, Ortwin


    The application of plasmonics to thermal emitters is generally assisted by absorptive losses in the metal because Kirchhoff’s law prescribes that only good absorbers make good thermal emitters. Based on a designed plasmonic crystal and exploiting a slow-wave lattice resonance and spontaneous thermal plasmon emission, we engineer a tungsten-based thermal emitter, fabricated in an industrial CMOS process, and demonstrate its markedly improved practical use in a prototype non-dispersive infrared (NDIR) gas-sensing device. We show that the emission intensity of the thermal emitter at the CO2 absorption wavelength is enhanced almost 4-fold compared to a standard non-plasmonic emitter, which enables a proportionate increase in the signal-to-noise ratio of the CO2 gas sensor.

  18. Pinning efficiency of splayed columnar defects in Bi-2212 single crystal: Evidence of a cage pinning effect (United States)

    Shaidiuk, V. A.; Ruyter, A.; Plessis, D.; Simon, Ch.; Maignan, A.; Wahl, A.; de Brion, S.; Ammor, L.


    A three-directional configuration of columnar defects has been induced in a Bi2Sr2CaCu2O8 single crystal by irradiation with heavy ions of high energy. Persistent current densities have been extracted, using the Bean model, from hysteresis loops recorded in the orientation H||c. We have shown that improvements in pinning properties are larger in this three-directional splayed configuration than in the one obtained with columnar defects parallel to the c-axis. This effect exists only for H larger than HΦ, where HΦ is the matching field, and disappears as temperature is increased and vortices become less stiff. This is the first time that such a beneficial effect is reported for a compound of such a high electronic anisotropy.

  19. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix


    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  20. Lunar Sample Display Locations (United States)

    National Aeronautics and Space Administration — NASA provides a number of lunar samples for display at museums, planetariums, and scientific expositions around the world. Lunar displays are open to the public....

  1. Tuning crystal phase of NiSx through electro-oxidized nickel foam: A novel route for preparing efficient electrocatalysts for oxygen evolution reaction (United States)

    Li, Xiao; Shang, Xiao; Rao, Yi; Dong, Bin; Han, Guan-Qun; Hu, Wen-Hui; Liu, Yan-Ru; Yan, Kai-Li; Chi, Jing-Qi; Chai, Yong-Ming; Liu, Chen-Guang


    A facile solvothermal sulfurization using electro-oxidized nickel foam (NF(Ox)) as support has been applied to prepare NiSx/NF(Ox) electrocatalyst with highly efficient activity for oxygen evolution reaction (OER). XRD patterns confirm the composition of NiSx/NF(Ox): two kinds of crystal phase including β-NiS and Ni3S2. While using bare NF as support under identical conditions, only Ni3S2 phase can be detected. SEM images reveal two kinds of morphologies of NiSx/NF(Ox) including pyramids structure of β-NiS and nanorod-like structure of Ni3S2, which implies the tuning effect of electro-pretreatment of NF on the selective preparation of NiSx crystal phase. It can be speculated that Ni(OH)2 layer derived from electro-oxidized NF is responsible for the growth of β-NiS while metallic Ni is transformed into Ni2S3 during sulfurization. Electrochemical measurements for OER indicate the enhanced electrocatalytic activity of NiSx/NF(Ox) with a small overpotential of 72 mV to reach 10 mA cm-2 compared with Ni3S2/NF, which may be ascribed to the improved electron-transfer kinetics relating to the unique atomic configurations and crystalline structures of β-NiS. The electro-oxidation pretreatment of nickel foam provides a simple and convenient method by tuning different NiSx crystal phases for preparing excellent OER eletrocatalysts.

  2. Generation of a compact high-power high-efficiency normal-dispersion pumping supercontinuum in silica photonic crystal fiber pumped with a 1064-nm picosecond pulse (United States)

    Chen, Hong-Wei; Jin, Ai-Jun; Yang, Wei-Qiang; Chen, Sheng-Ping; Hou, Jing; Lu, Qi-Sheng


    Broadband normal dispersion pumping supercontinuum (SC) generation in silica photonic crystal fiber (PCF) is investigated in this paper. A 1064-nm picosecond fiber laser is used to pump silica PCF for the SC generation. The length of PCF is optimized for the most efficient stimulated Raman scattering process in the picosecond pump pulse region. The first stimulated Raman Stokes peak is located in the anomalous dispersion regime of the PCF and near the zero dispersion wavelength; thus the SC generation process can benefit from both a normal dispersion pumping scheme and an anomalous dispersion pumping scheme. The 51.7-W SC spanning from about 700 nm to beyond 1700 nm is generated with an all-fiber configuration, and the pump-to-SC conversion efficiency is up to 90%. In order to avoid the output fiber end face damage and increase the stability of the system, an improved output solution for the high power SC is proposed in our experiment. This high-efficiency near-infrared SC source is very suitable for applications in which average output power and spectral power density are firstly desirable.

  3. Efficient and broadband Stokes wave generation by degenerate four-wave mixing at the mid-infrared wavelength in a silica photonic crystal fiber. (United States)

    Yuan, Jinhui; Sang, Xinzhu; Wu, Qiang; Zhou, Guiyao; Yu, Chongxiu; Wang, Kuiru; Yan, Binbin; Han, Ying; Farrell, Gerald; Hou, Lantian


    Based on degenerate four-wave mixing (FWM), the broadband Stokes waves are efficiently generated at the mid-infrared wavelength above 2 μm, for the first time to our knowledge, by coupling the femtosecond pulses into the fundamental mode of a silica photonic crystal fiber designed and fabricated in our laboratory. Influences of the power and wavelength of pump pulses on the phase-matched frequency conversion process are discussed. When pump pulses with central wavelength of 815 nm and average power of 300 mW are used, the output power ratio of the Stokes wave generated at 2226 nm and the residual pump wave P(s)/P(res) is estimated to be 10.8:1, and the corresponding conversion efficiency η(s) and bandwidth B(s) of the Stokes wave can be up to 26% and 33 nm, respectively. The efficient and broadband Stokes waves can be used as the ultrashort pulse sources for mid-infrared photonics and spectroscopy.

  4. Generation of a compact high-power high-efficiency normal-dispersion pumping supercontinuum in silica photonic crystal fiber pumped with a 1064-nm picosecond pulse

    Institute of Scientific and Technical Information of China (English)

    Chen Hong-Wei; Jin Ai-Jun; Yang Wei-Qiang; Chen Sheng-Ping; Hou Jing; Lu Qi-Sheng


    Broadband normal dispersion pumping supercontinuum (SC) generation in silica photonic crystal fiber (PCF) is investigated in this paper.A 1064-nm picosecond fiber laser is used to pump silica PCF for the SC generation.The length of PCF is optimized for the most efficient stimulated Raman scattering process in the picosecond pump pulse region.The first stimulated Raman Stokes peak is located in the anomalous dispersion regime of the PCF and near the zero dispersion wavelength; thus the SC generation process can benefit from both a normal dispersion pumping scheme and an anomalous dispersion pumping scheme.The 51.7-W SC spanning from about 700 nm to beyond 1700 nm is generated with an all-fiber configuration,and the pump-to-SC conversion efficiency is up to 90%.In order to avoid the output fiber end face damage and increase the stability of the system,an improved output solution for the high power SC is proposed in our experiment.This high-efficiency near-infrared SC source is very suitable for applications in which average output power and spectral power density are firstly desirable.

  5. High-Efficiency Intracavity Continuous-Wave Green-Light Generation by Quasiphase Matching in a Bulk Periodically Poled MgO:LiNbO3 Crystal

    Directory of Open Access Journals (Sweden)

    Yong Bi


    Full Text Available 908 mW of green light at 532 nm were generated by intracavity quasiphase matching in a bulk periodically poled MgO:LiNbO3 (PPMgLN crystal. A maximum optical-to-optical conversion efficiency of 33.5% was obtained from a 0.5 mm thick, 10 mm long, and 5 mol% MgO:LiNbO3 crystal with an end-pump power of 2.7 W at 808 nm. The temperature bandwidth between the intracavity and single-pass frequency doubling was found to be different for the PPMgLN. Reliability and stability of the green laser were evaluated. It was found that for continuous operation of 100 hours, the output stability was better than 97.5% and no optical damage was observed.

  6. Efficient monitoring of the blood-stage infection in a malaria rodent model by the rotating-crystal magneto-optical method (United States)

    Orbán, Ágnes; Rebelo, Maria; Molnár, Petra; Albuquerque, Inês S.; Butykai, Adam; Kézsmárki, István


    Intense research efforts have been focused on the improvement of the efficiency and sensitivity of malaria diagnostics, especially in resource-limited settings for the detection of asymptomatic infections. Our recently developed magneto-optical (MO) method allows the accurate quantification of malaria pigment crystals (hemozoin) in blood by their magnetically induced rotation. First evaluations of the method using β-hematin crystals and in vitro P. falciparum cultures implied its potential for high-sensitivity malaria diagnosis. To further investigate this potential, here we study the performance of the method in monitoring the in vivo onset and progression of the blood-stage infection in a rodent malaria model. Our results show that the MO method can detect the first generation of intraerythrocytic P. berghei parasites 66-76 hours after sporozoite injection, demonstrating similar sensitivity to Giesma-stained light microscopy and exceeding that of flow cytometric techniques. Magneto-optical measurements performed during and after the treatment of P. berghei infections revealed that both the follow up under treatment and the detection of later reinfections are feasible with this new technique. The present study demonstrates that the MO method - besides being label and reagent-free, automated and rapid - has a high in vivo sensitivity and is ready for in-field evaluation.

  7. Crystallization of perovskite film using ambient moisture and water as co-solvent for efficient planar perovskite solar cell (Conference Presentation) (United States)

    Dubey, Ashish; Reza, Khan M.; Gaml, Eman; Adhikari, Nirmal; Qiao, Qiquan


    Smooth, compact and defect free morphology of perovskite is highly desired for enhanced device performance. Several routes such as thermal annealing, use of solvent mixtures, growth under controlled humidity has been adopted to obtain crystalline, smooth and defect free perovskite film. Herein we showed direct use of water (H2O) as co-solvent in precursor solution and have optimized the water content required to obtain smooth and dense film. Varying concentration of water was used in precursor solution of CH3NH3I and PbI2 mixed in γ-butyrolactone (GBL) and dimethylsulfoxide (DMSO). Perovskite films were crystallized using toluene assisted solvent engineering method using GBL:DMSO:H2O as solvent mixture. The amount of water was varied from 1% to 25%, which resulted in change in film morphology and perovskite crystallinity. It was concluded that an appropriate amount of water is required to assist the crystallization process to obtain smooth pin-hole free morphology. The change in morphology led to improved fill factor in the device, with highest efficiency 14%, which was significantly higher than devices made from perovskite film without adding water. We also showed that addition of up to 25% by volume of water does not significantly change the device performance.

  8. Radially oriented mesoporous TiO2 microspheres with single-crystal-like anatase walls for high-efficiency optoelectronic devices. (United States)

    Liu, Yong; Che, Renchao; Chen, Gang; Fan, Jianwei; Sun, Zhenkun; Wu, Zhangxiong; Wang, Minghong; Li, Bin; Wei, Jing; Wei, Yong; Wang, Geng; Guan, Guozhen; Elzatahry, Ahmed A; Bagabas, Abdulaziz A; Al-Enizi, Abdullah M; Deng, Yonghui; Peng, Huisheng; Zhao, Dongyuan


    Highly crystalline mesoporous materials with oriented configurations are in demand for high-performance energy conversion devices. We report a simple evaporation-driven oriented assembly method to synthesize three-dimensional open mesoporous TiO2 microspheres with a diameter of ~800 nm, well-controlled radially oriented hexagonal mesochannels, and crystalline anatase walls. The mesoporous TiO2 spheres have a large accessible surface area (112 m(2)/g), a large pore volume (0.164 cm(3)/g), and highly single-crystal-like anatase walls with dominant (101) exposed facets, making them ideal for conducting mesoscopic photoanode films. Dye-sensitized solar cells (DSSCs) based on the mesoporous TiO2 microspheres and commercial dye N719 have a photoelectric conversion efficiency of up to 12.1%. This evaporation-driven approach can create opportunities for tailoring the orientation of inorganic building blocks in the assembly of various mesoporous materials.

  9. Liquid Crystal Motion Picture Projector①

    Institute of Scientific and Technical Information of China (English)



    A liquid crystal moving picture projector and method are described.Light incident on a liquid crystal display-type device is selectively scattered or transmitted by respective portions of liquid crystal display,and a projection mechanism projects an image formed by either such scattered light or such transmitted light.A liquid cystal moving picture projector includes a liquid crystal display for creating characteristics of an image,and projecttion optics for projecting images sequentially created by the display.The display includes a liquid crystal material capable of temporary storing information at respective areas.The temporary storage may be a function of charge storing directly on liquid crystal material.A method of projecting plural images in sequence includes:creating an image or characteristics of an image in a liquid crystal material,storing such image in such liquid crystal material,directing light at such liquid crystal material,projecting such image as a function of light transmitted through or scattered by such liquid crystal material,and creating a further image in such liquid crystal material for subsequent projection.

  10. Optical, phonon and efficient visible and infrared photocatalytic activity of Cu doped ZnS micro crystals (United States)

    Prasad, Neena; Balasubramanian, Karthikeyan


    We report, the enhanced photocatalytic behaviour of Cu doped ZnS micro crystals. ZnS and different concentrations of Cu doped ZnS microcrystals were prepared. X-ray diffraction confirms the crystalline and phase of the particles. Morphology and sizes were studied using Scanning Electron Microscopy (SEM). Recorded optical absorption spectra show a band for around 365 nm for pure ZnS, but there is a broad band in the near infrared regime for the Cu-doped ZnS microcrystals which are attributed to the d-d transitions of Cu2 + ions. Phonon properties of as-prepared samples were investigated using Raman spectroscopy. Present work we investigate the potential of ZnS and Cu doped ZnS as a photocatalyst. For this from the degradation of methylene blue dye in aqueous media the photocatalytic activity of pure and highest doped ZnS samples with the irradiation of white light and infrared, enhanced photocatalytic activity were observed. Mechanism of white light an IR light based photocatalytic activity is explained based on the electron-hole pair production.

  11. The VLT Real Time Display (United States)

    Herlin, T.; Brighton, A.; Biereichel, P.

    The VLT Real-Time Display (RTD) software was developed in order to support image display in real-time, providing a tool for users to display video like images from a camera or detector as fast as possible on an X-Server. The RTD software is implemented as a package providing a Tcl/Tk image widget written in C++ and an independent image handling library and can be used as a building block, adding display capabilities to dedicated VLT control applications. The RTD widget provides basic image display functionality like: panning, zooming, color scaling, colormaps, intensity changes, pixel query, overlaying of line graphics. A large set of assisting widgets, e.g., colorbar, zoom window, spectrum plot are provided to enable the building of image applications. The support for real-time is provided by an RTD image event mechanism used for camera or detector subsystems to pass images to the RTD widget. Image data are passed efficiently via shared memory. This paper describes the architecture of the RTD software and summarizes the features provided by RTD.

  12. New ultraportable display technology and applications (United States)

    Alvelda, Phillip; Lewis, Nancy D.


    MicroDisplay devices are based on a combination of technologies rooted in the extreme integration capability of conventionally fabricated CMOS active-matrix liquid crystal display substrates. Customized diffraction grating and optical distortion correction technology for lens-system compensation allow the elimination of many lenses and systems-level components. The MicroDisplay Corporation's miniature integrated information display technology is rapidly leading to many new defense and commercial applications. There are no moving parts in MicroDisplay substrates, and the fabrication of the color generating gratings, already part of the CMOS circuit fabrication process, is effectively cost and manufacturing process-free. The entire suite of the MicroDisplay Corporation's technologies was devised to create a line of application- specific integrated circuit single-chip display systems with integrated computing, memory, and communication circuitry. Next-generation portable communication, computer, and consumer electronic devices such as truly portable monitor and TV projectors, eyeglass and head mounted displays, pagers and Personal Communication Services hand-sets, and wristwatch-mounted video phones are among the may target commercial markets for MicroDisplay technology. Defense applications range from Maintenance and Repair support, to night-vision systems, to portable projectors for mobile command and control centers.

  13. Easily accessible polymer additives for tuning the crystal-growth of perovskite thin-films for highly efficient solar cells. (United States)

    Dong, Qingqing; Wang, Zhaowei; Zhang, Kaicheng; Yu, Hao; Huang, Peng; Liu, Xiaodong; Zhou, Yi; Chen, Ning; Song, Bo


    For perovskite solar cells (Pero-SCs), one of the key issues with respect to the power conversion efficiency (PCE) is the morphology control of the perovskite thin-films. In this study, an easily-accessible additive polyethylenimine (PEI) is utilized to tune the morphology of CH3NH3PbI3-xClx. With addition of 1.00 wt% of PEI, the smoothness and crystallinity of the perovskite were greatly improved, which were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). A summit PCE of 14.07% was achieved for the p-i-n type Pero-SC, indicating a 26% increase compared to those of the devices without the additive. Both photoluminescence (PL) and alternating current impedance spectroscopy (ACIS) analyses confirm the efficiency results after the addition of PEI. This study provides a low-cost polymer additive candidate for tuning the morphology of perovskite thin-films, and might be a new clue for the mass production of Pero-SCs.

  14. Invisible Display in Aluminum

    DEFF Research Database (Denmark)

    Prichystal, Jan Phuklin; Hansen, Hans Nørgaard; Bladt, Henrik Henriksen


    Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish for an integ...... be obtained by shining light from the backside of the workpiece. When there is no light from the backside, the front surface seems totally untouched. This was achieved by laser ablation with ultra-short pulses.......Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish...... for an integrated display in a metal surface is often ruled by design and functionality of a product. The integration of displays in metal surfaces requires metal removal in order to clear the area of the display to some extent. The idea behind an invisible display in Aluminum concerns the processing of a metal...

  15. Compact efficient Q-switched eye-safe laser at 1525 nm with a double-end diffusion-bonded Nd:YVO4 crystal as a self-Raman medium. (United States)

    Chang, Y T; Su, K W; Chang, H L; Chen, Y F


    We report on an efficient Q-switched eye-safe laser at 1525 nm with a double-end diffusion-bonded Nd:YVO(4) crystal as a self-Raman gain medium. A diffusion-bonded crystal not only reduces the thermal effects but also increase the interaction length for the stimulated Raman scattering. With an input pump power of 17.2 W, average power of 2.23 W at the first- Stokes wavelength of 1525 nm is generated at a pulse repetition rate of 40 kHz, corresponding to a conversion efficiency of 13%.

  16. Fundamentals of liquid crystal devices

    CERN Document Server

    Yang, Deng-Ke


    Revised throughout to cover the latest developments in the fast moving area of display technology, this 2nd edition of Fundamentals of Liquid Crystal Devices, will continue to be a valuable resource for those wishing to understand the operation of liquid crystal displays. Significant updates include new material on display components, 3D LCDs and blue-phase displays which is one of the most promising new technologies within the field of displays and it is expected that this new LC-technology will reduce the response time and the number of optical components of LC-modules. Prof. Yang is a pion

  17. Polyplanar optic display

    Energy Technology Data Exchange (ETDEWEB)

    Veligdan, J.; Biscardi, C.; Brewster, C.; DeSanto, L. [Brookhaven National Lab., Upton, NY (United States). Dept. of Advanced Technology; Beiser, L. [Leo Beiser Inc., Flushing, NY (United States)


    The Polyplanar Optical Display (POD) is a unique display screen which can be used with any projection source. This display screen is 2 inches thick and has a matte black face which allows for high contrast images. The prototype being developed is a form, fit and functional replacement display for the B-52 aircraft which uses a monochrome ten-inch display. The new display uses a 100 milliwatt green solid state laser (532 nm) as its optical source. In order to produce real-time video, the laser light is being modulated by a Digital Light Processing (DLP{trademark}) chip manufactured by Texas Instruments, Inc. A variable astigmatic focusing system is used to produce a stigmatic image on the viewing face of the POD. In addition to the optical design, the authors discuss the electronic interfacing to the DLP{trademark} chip, the opto-mechanical design and viewing angle characteristics.

  18. A comparison of leaf crystal macropatterns in the two sister genera Piper and Peperomia (Piperaceae). (United States)

    Horner, Harry T; Wanke, Stefan; Samain, Marie-Stéphanie


    This is the first large-scale study comparing leaf crystal macropatterns of the species-rich sister genera Piper and Peperomia. It focuses on identifying types of calcium oxalate crystals and their macropatterns in leaves of both genera. The Piper results are placed in a phylogenetic context to show evolutionary patterns. This information will expand knowledge about crystals and provide specific examples to help study their form and function. One example is the first-time observation of Piper crystal sand tumbling in chlorenchyma vacuoles. Herbarium and fresh leaves were cleared of cytoplasmic content and examined with polarizing microscopy to identify types of crystals and their macropatterns. Selected hydrated herbarium and fresh leaf punches were processed for scanning electron microscopy and x-ray elemental analysis. Vibratome sections of living Piper and Peperomia leaves were observed for anatomical features and crystal movement. Both genera have different leaf anatomies. Piper displays four crystal types in chlorenchyma-crystal sand, raphides, styloids, and druses, whereas Peperomia displays three types-druses, raphides, and prisms. Because of different leaf anatomies and crystal types between the genera, macropatterns are completely different. Crystal macropattern evolution in both is characterized by increasing complexity, and both may use their crystals for light gathering and reflection for efficient photosynthesis under low-intensity light environments. Both genera have different leaf anatomies, types of crystals and crystal macropatterns. Based on Piper crystals associated with photosynthetic tissues and low-intensity light, further study of their function and association with surrounding chloroplasts is warranted, especially active crystal movement.

  19. Efficient optical pumping and high optical depth in a hollow-core photonic-crystal fibre for a broadband quantum memory

    CERN Document Server

    Sprague, Michael R; Abdolvand, Amir; Nunn, Joshua; Jin, Xian-Min; Kolthammer, W Steven; Barbieri, Marco; Rigal, Bruno; Michelberger, Patrick S; Champion, Tessa F M; Russell, Philip St J; Walmsley, Ian A


    The generation of large multiphoton quantum states - for applications in computing, metrology, and simulation - requires a network of high-efficiency quantum memories capable of storing broadband pulses. Integrating these memories into a fibre offers a number of advantages towards realising this goal: strong light-matter coupling at low powers, simplified alignment, and compatibility with existing photonic architectures. Here, we introduce a large-core kagome-structured hollow-core fibre as a suitable platform for an integrated fibre-based quantum memory with a warm atomic vapour. We demonstrate, for the first time, efficient optical pumping in a hollow-core photonic-crystal fibre with a warm atomic vapour, where (90 $\\pm$ 1)% of atoms are prepared in the ground state. We measure high optical depths (3$\\times 10^{4}$) and, also, narrow homogeneous linewidths that do not exhibit significant transit-time broadening. Our results establish that kagome fibres are suitable for implementing a broadband, room-tempera...

  20. Controlled Crystal Grain Growth in Mixed Cation-Halide Perovskite by Evaporated Solvent Vapor Recycling Method for High Efficiency Solar Cells. (United States)

    Numata, Youhei; Kogo, Atsushi; Udagawa, Yosuke; Kunugita, Hideyuki; Ema, Kazuhiro; Sanehira, Yoshitaka; Miyasaka, Tsutomu


    We developed a new and simple solvent vapor-assisted thermal annealing (VA) procedure which can reduce grain boundaries in a perovskite film for fabricating highly efficient perovskite solar cells (PSCs). By recycling of solvent molecules evaporated from an as-prepared perovskite film as a VA vapor source, named the pot-roast VA (PR-VA) method, finely controlled and reproducible device fabrication was achieved for formamidinium (FA) and methylammonium (MA) mixed cation-halide perovskite (FAPbI3)0.85(MAPbBr3)0.15. The mixed perovskite was crystallized on a low-temperature prepared brookite TiO2 mesoporous scaffold. When exposed to very dilute solvent vapor, small grains in the perovskite film gradually unified into large grains, resulting in grain boundaries which were highly reduced and improvement of photovoltaic performance in PSC. PR-VA-treated large grain perovskite absorbers exhibited stable photocurrent-voltage performance with high fill factor and suppressed hysteresis, achieving the best conversion efficiency of 18.5% for a 5 × 5 mm(2) device and 15.2% for a 1.0 × 1.0 cm(2) device.

  1. Macro Domain from Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Is an Efficient ADP-ribose Binding Module: CRYSTAL STRUCTURE AND BIOCHEMICAL STUDIES. (United States)

    Cho, Chao-Cheng; Lin, Meng-Hsuan; Chuang, Chien-Ying; Hsu, Chun-Hua


    The newly emerging Middle East respiratory syndrome coronavirus (MERS-CoV) encodes the conserved macro domain within non-structural protein 3. However, the precise biochemical function and structure of the macro domain is unclear. Using differential scanning fluorimetry and isothermal titration calorimetry, we characterized the MERS-CoV macro domain as a more efficient adenosine diphosphate (ADP)-ribose binding module than macro domains from other CoVs. Furthermore, the crystal structure of the MERS-CoV macro domain was determined at 1.43-Å resolution in complex with ADP-ribose. Comparison of macro domains from MERS-CoV and other human CoVs revealed structural differences in the α1 helix alters how the conserved Asp-20 interacts with ADP-ribose and may explain the efficient binding of the MERS-CoV macro domain to ADP-ribose. This study provides structural and biophysical bases to further evaluate the role of the MERS-CoV macro domain in the host response via ADP-ribose binding but also as a potential target for drug design.

  2. Analysis of the light-extraction efficiency of SiC substrate-based flip-chip vertical light-emitting diodes with embedded photonic crystals (United States)

    Liu, Meng; Li, Kang; Kong, Fan-min; Zhao, Jia; Zhao, Shu-long; Meng, Hao-tian


    To improve the light-extraction efficiency (LEE) of flip-chip vertical light-emitting diodes (LEDs) grown on silicon carbide (SiC) substrate, embedded photonic crystals (PhCs) were alternatively introduced into the n-GaN layer of LEDs, since etching of the SiC substrate was very difficult. The finite-difference time-domain (FDTD) method was employed to investigate the combination effects of the micro-cavity and the embedded PhCs. The influences of the PhCs configurations on the LEE of LEDs were also examined to get an optimal structure. With the optimized parameters, about 20% enhancement of LEE was achieved comparing to planar SiC substrate-based flip-chip vertical LEDs. The LEE of conventional surface PhCs LEDs and double layer PhCs LEDs were also investigated for comparison. The results indicated that LEDs with carefully designed embedded PhCs could provide more LEE than surface PhCs LEDs. The structures proposed here offered scopes for the design of high-efficiency, high-power LEDs.

  3. Scalable Resolution Display Walls

    KAUST Repository

    Leigh, Jason


    This article will describe the progress since 2000 on research and development in 2-D and 3-D scalable resolution display walls that are built from tiling individual lower resolution flat panel displays. The article will describe approaches and trends in display hardware construction, middleware architecture, and user-interaction design. The article will also highlight examples of use cases and the benefits the technology has brought to their respective disciplines. © 1963-2012 IEEE.

  4. Crystal Structures of the uL3 Mutant Ribosome: Illustration of the Importance of Ribosomal Proteins for Translation Efficiency. (United States)

    Mailliot, Justine; Garreau de Loubresse, Nicolas; Yusupova, Gulnara; Meskauskas, Arturas; Dinman, Jonathan D; Yusupov, Marat


    The ribosome has been described as a ribozyme in which ribosomal RNA is responsible for peptidyl-transferase reaction catalysis. The W255C mutation of the universally conserved ribosomal protein uL3 has diverse effects on ribosome function (e.g., increased affinities for transfer RNAs, decreased rates of peptidyl-transfer), and cells harboring this mutation are resistant to peptidyl-transferase inhibitors (e.g., anisomycin). These observations beg the question of how a single amino acid mutation may have such wide ranging consequences. Here, we report the structure of the vacant yeast uL3 W255C mutant ribosome by X-ray crystallography, showing a disruption of the A-site side of the peptidyl-transferase center (PTC). An additional X-ray crystallographic structure of the anisomycin-containing mutant ribosome shows that high concentrations of this inhibitor restore a "WT-like" configuration to this region of the PTC, providing insight into the resistance mechanism of the mutant. Globally, our data demonstrate that ribosomal protein uL3 is structurally essential to ensure an optimal and catalytically efficient organization of the PTC, highlighting the importance of proteins in the RNA-centered ribosome.

  5. Comprehensive study on different crystal field environments in highly efficient NaLaF4:Er3+ upconversion phosphor (United States)

    Sarakovskis, Anatolijs; Krieke, Guna; Doke, Guna; Grube, Jurgis; Grinberga, Liga; Springis, Maris


    Complex fluorides, especially rare-earth doped NaREF4 (RE = Y3+, La3+ or Gd3+), are promising materials for the upconversion luminescence mostly due to low phonon energy of their matrices and multisite nature of the crystalline lattice. Although multisite formation in hexagonal NaREF4 structures has generally been proved, the actual number of the active sites in different structures varies from two (NaGdF4) to seven (NaYF4). The aim of this work has been to study multisite formation in NaLaF4:Er3+. For this purpose low-temperature site-selective spectroscopy measurements in hexagonal NaLaF4:Er3+ have been performed. Excitation at different wavelengths corresponding to the excitation of 4F7/2 level of Er3+ ions has revealed three distinct luminescence spectra in the green spectral region associated with 4S3/2 → 4I15/2 electronic transition. The number of the spectra has been sufficient to model experimentally measured luminescence spectra at any excitation wavelength as a linear combination of the distinct spectra. The analysis of the structure of the material and the results of site-selective spectroscopy signify the presence of at least three different crystalline field environments where Er3+ ions incorporate. Upon site-selective excitation of Er3+ located at a specific site energy transfer to erbium ions located at other sites has been observed in both the upconversion and downconversion luminescence processes. The enhanced energy transfer between the different sites in NaLaF4:Er3+ signifies the importance of the multisite nature of the structure, which is a key factor for an efficient upconversion luminescence.

  6. Standardizing visual display quality

    NARCIS (Netherlands)

    Besuijen, Ko; Spenkelink, Gerd P.J.


    The current ISO 9241–3 standard for visual display quality and the proposed user performance tests are reviewed. The standard is found to be more engineering than ergonomic and problems with system configuration, software applications, display settings, user behaviour, wear and physical environment

  7. Polyplanar optical display electronics

    Energy Technology Data Exchange (ETDEWEB)

    DeSanto, L.; Biscardi, C. [Brookhaven National Lab., Upton, NY (United States). Dept. of Advanced Technology


    The Polyplanar Optical Display (POD) is a unique display screen which can be used with any projection source. The prototype ten inch display is two inches thick and has a matte black face which allows for high contrast images. The prototype being developed is a form, fit and functional replacement display for the B-52 aircraft which uses a monochrome ten-inch display. In order to achieve a long lifetime, the new display uses a 100 milliwatt green solid-state laser (10,000 hr. life) at 532 nm as its light source. To produce real-time video, the laser light is being modulated by a Digital Light Processing (DLP{trademark}) chip manufactured by Texas Instruments. In order to use the solid-state laser as the light source and also fit within the constraints of the B-52 display, the Digital Micromirror Device (DMD{trademark}) circuit board is removed from the Texas Instruments DLP light engine assembly. Due to the compact architecture of the projection system within the display chassis, the DMD{trademark} chip is operated remotely from the Texas Instruments circuit board. The authors discuss the operation of the DMD{trademark} divorced from the light engine and the interfacing of the DMD{trademark} board with various video formats (CVBS, Y/C or S-video and RGB) including the format specific to the B-52 aircraft. A brief discussion of the electronics required to drive the laser is also presented.

  8. Helmet-Mounted Displays (HMD) (United States)

    Federal Laboratory Consortium — The Helmet-Mounted Display labis responsible for monocular HMD day display evaluations; monocular HMD night vision performance processes; binocular HMD day display...

  9. Visual merchandising window display

    Directory of Open Access Journals (Sweden)

    Opris (Cas. Stanila M.


    Full Text Available Window display plays a major part in the selling strategies; it does not only include the simple display of goods, nowadays it is a form of art, also having the purpose of sustaining the brand image. This article wants to reveal the tools that are essential in creating a fabulous window display. Being a window designer is not an easy job, you have to always think ahead trends, to have a sense of colour, to know how to use light to attract customers in the store after only one glance at the window. The big store window displays are theatre scenes: with expensive backgrounds, special effects and high fashion mannequins. The final role of the displays is to convince customers to enter the store and trigger the purchasing act which is the final goal of the retail activity.

  10. Fluorescent protein integrated white LEDs for displays (United States)

    Press, Daniel Aaron; Melikov, Rustamzhon; Conkar, Deniz; Nur Firat-Karalar, Elif; Nizamoglu, Sedat


    The usage time of displays (e.g., TVs, mobile phones, etc) is in general shorter than their functional life time, which worsens the electronic waste (e-waste) problem around the world. The integration of biomaterials into electronics can help to reduce the e-waste problem. In this study, we demonstrate fluorescent protein integrated white LEDs to use as a backlight source for liquid crystal (LC) displays for the first time. We express and purify enhanced green fluorescent protein (eGFP) and monomeric Cherry protein (mCherry), and afterward we integrate these proteins as a wavelength-converter on a blue LED chip. The protein-integrated backlight exhibits a high luminous efficacy of 248 lm/Wopt and the area of the gamut covers 80% of the NTSC color gamut. The resultant colors and objects in the image on the display can be well observed and distinguished. Therefore, fluorescent proteins show promise for display applications.

  11. Defense display market assessment (United States)

    Desjardins, Daniel D.; Hopper, Darrel G.


    This paper addresses the number, function and size of principal military displays and establishes a basis to determine the opportunities for technology insertion in the immediate future and into the next millennium. Principal military displays are defined as those occupying appreciable crewstation real-estate and/or those without which the platform could not carry out its intended mission. DoD 'office' applications are excluded from this study. The military displays market is specified by such parameters as active area and footprint size, and other characteristics such as luminance, gray scale, resolution, angle, color, video capability, and night vision imaging system (NVIS) compatibility. Funded, future acquisitions, planned and predicted crewstation modification kits, and form-fit upgrades are taken into account. This paper provides an overview of the DoD niche market, allowing both government and industry a necessary reference by which to meet DoD requirements for military displays in a timely and cost-effective manner. The aggregate DoD market for direct-view and large-area military displays is presently estimated to be in excess of 242,000. Miniature displays are those which must be magnified to be viewed, involve a significantly different manufacturing paradigm and are used in helmet mounted displays and thermal weapon sight applications. Some 114,000 miniature displays are presently included within Service weapon system acquisition plans. For vendor production planning purposes it is noted that foreign military sales could substantially increase these quantities. The vanishing vendor syndrome (VVS) for older display technologies continues to be a growing, pervasive problem throughout DoD, which consequently must leverage the more modern display technologies being developed for civil- commercial markets.

  12. Polarized quantum dot emission in electrohydrodynamic jet printed photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    See, Gloria G. [Micro and Nanotechnology Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 208 North Wright Street, Urbana, Illinois 61801 (United States); Xu, Lu; Nuzzo, Ralph G. [Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801 (United States); Sutanto, Erick; Alleyne, Andrew G. [Mechanical Science and Engineering Department, University of Illinois at Urbana-Champaign, 154 Mechanical Engineering Building, Urbana, Illinois 61801 (United States); Cunningham, Brian T. [Micro and Nanotechnology Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 208 North Wright Street, Urbana, Illinois 61801 (United States); Department of Bioengineering, University of Illinois at Urbana-Champaign, 1270 Digital Computer Laboratory, MC-278, Urbana, Illinois 61801 (United States)


    Tailored optical output, such as color purity and efficient optical intensity, are critical considerations for displays, particularly in mobile applications. To this end, we demonstrate a replica molded photonic crystal structure with embedded quantum dots. Electrohydrodynamic jet printing is used to control the position of the quantum dots within the device structure. This results in significantly less waste of the quantum dot material than application through drop-casting or spin coating. In addition, the targeted placement of the quantum dots minimizes any emission outside of the resonant enhancement field, which enables an 8× output enhancement and highly polarized emission from the photonic crystal structure.

  13. Panoramic projection avionics displays (United States)

    Kalmanash, Michael H.


    Avionics projection displays are entering production in advanced tactical aircraft. Early adopters of this technology in the avionics community used projection displays to replace or upgrade earlier units incorporating direct-view CRT or AMLCD devices. Typical motivation for these upgrades were the alleviation of performance, cost and display device availability concerns. In these systems, the upgraded (projection) displays were one-for-one form / fit replacements for the earlier units. As projection technology has matured, this situation has begun to evolve. The Lockheed-Martin F-35 is the first program in which the cockpit has been specifically designed to take advantage of one of the more unique capabilities of rear projection display technology, namely the ability to replace multiple small screens with a single large conformal viewing surface in the form of a panoramic display. Other programs are expected to follow, since the panoramic formats enable increased mission effectiveness, reduced cost and greater information transfer to the pilot. Some of the advantages and technical challenges associated with panoramic projection displays for avionics applications are described below.

  14. A Unique 10 Segment Display for Bengali Numerals

    CERN Document Server

    Azad, Md Abul Kalam; Ahmad, Shabbir; Kamruzzaman, S M


    Segmented display is widely used for efficient display of alphanumeric characters. English numerals are displayed by 7 segment and 16 segment display. The segment size is uniform in this two display architecture. Display architecture using 8, 10, 11, 18 segments have been proposed for Bengali numerals 0...9 yet no display architecture is designed using segments of uniform size and uniform power consumption. In this paper we have proposed a uniform 10 segment architecture for Bengali numerals. This segment architecture uses segments of uniform size and no bent segment is used.

  15. A Liquid Crystal Displayed Method of I/O Bus Driving Based on CPLD%一种基于CPLD的I/O总线驱动液晶显示的方法

    Institute of Scientific and Technical Information of China (English)

    程晓东; 郑为民; 唐志敏


    The paper discusses a new kind of driving the LCD via I/O bus using CPLD and realizing the precise I/Ocontrol timing sequence by establishing the corresponding Verilog-HDL model. The results of application show thatthis solution can not only solve the matching of low-speed device with high-speed bus but also provide the display in-terface during the motherboard debugging process, and also prove that the whole system is reliable and stable.

  16. Crosstalk in stereoscopic displays: a review (United States)

    Woods, Andrew J.


    Crosstalk, also known as ghosting or leakage, is a primary factor in determining the image quality of stereoscopic three dimensional (3D) displays. In a stereoscopic display, a separate perspective view is presented to each of the observer's two eyes in order to experience a 3D image with depth sensation. When crosstalk is present in a stereoscopic display, each eye will see a combination of the image intended for that eye, and some of the image intended for the other eye-making the image look doubled or ghosted. High levels of crosstalk can make stereoscopic images hard to fuse and lack fidelity, so it is important to achieve low levels of crosstalk in the development of high-quality stereoscopic displays. Descriptive and mathematical definitions of these terms are formalized and summarized. The mechanisms by which crosstalk occurs in different stereoscopic display technologies are also reviewed, including micropol 3D liquid crystal displays (LCDs), autostereoscopic (lenticular and parallax barrier), polarized projection, anaglyph, and time-sequential 3D on LCDs, plasma display panels and cathode ray tubes. Crosstalk reduction and crosstalk cancellation are also discussed along with methods of measuring and simulating crosstalk.

  17. Potential improvements for dual directional view displays. (United States)

    Mather, Jonathan; Parry Jones, Lesley; Gass, Paul; Imai, Akira; Takatani, Tomoo; Yabuta, Koji


    Dual directional view (DDV) displays show different images to different viewers. For example, the driver of a car looking at a central DDV display could view navigation information, while the passenger, looking from a different angle, could be watching a movie. This technology, which has now established itself on the dashboards of high-end Jaguar, Mercedes, and Range Rover cars, is manufactured by Sharp Corporation using a well-known parallax barrier technique. Unfortunately parallax barriers are associated with an inevitable drop in brightness compared with a single view display. A parallax barrier-based DDV display typically has less than half the transmission of a single view display. Here we present a solution to these problems via the use of a combined microlens and parallax barrier system, which can not only boost the brightness by 55% from a parallax barrier-only system but increase the head freedom by 25% and reduce crosstalk also. However, the use of microlenses (which must be positioned between the polarizers of the LCD) can adversely affect the contrast ratio of the display. Careful choice of the LCD mode is therefore required in order to create a DDV display that is both high in brightness and contrast ratio. The use of a single-domain vertically aligned nematic (VAN) liquid crystal (LC) mode, together with a microlens plus parallax barrier system can achieve this with a contrast ratio of 1700∶1 measured at 30° to normal incidence.

  18. β-Keto-enol Tethered Pyridine and Thiophene: Synthesis, Crystal Structure Determination and Its Organic Immobilization on Silica for Efficient Solid-Liquid Extraction of Heavy Metals. (United States)

    Radi, Smaail; Tighadouini, Said; Bacquet, Maryse; Degoutin, Stephanie; Dacquin, Jean-Philippe; Eddike, Driss; Tillard, Monique; Mabkhot, Yahia N


    Molecules bearing β-keto-enol functionality are potential candidates for coordination chemistry. Reported herein is the first synthesis and use of a novel designed ligand based on β-keto-enol group embedded with pyridine and thiophene moieties. The product was prepared in a one-step procedure by mixed Claisen condensation and was characterized by EA, m/z, FT-IR, (¹H, (13)C) NMR and single-crystal X-ray diffraction analysis. The new structure was grafted onto silica particles to afford a chelating matrix which was well-characterized by EA, FT-IR, solid-state (13)C-NMR, BET, BJH, SEM and TGA. The newly prepared organic-inorganic material was used as an adsorbent for efficient solid-phase extraction (SPE) of Cu(II), Zn(II), Cd(II) and Pb(II) from aqueous solutions and showed a capture capacity of 104.12 mg·g(-1), 98.90 mg·g(-1), 72.02 mg·g(-1), and 65.54 mg·g(-1), respectively. The adsorption capacity was investigated, in a batch method, using time of contact, pH, initial concentration, kinetics (Langmuir and Freundlich models), and thermodynamic parameters (ΔG°, ΔH° and ΔS°) of the system effects.

  19. Small - Display Cartography

    DEFF Research Database (Denmark)

    Nissen, Flemming; Hvas, Anders; Münster-Swendsen, Jørgen

    This report comprises the work carried out in the work-package of small display cartography. The work-package has aimed at creating a general framework for the small-display cartography. A solid framework facilitates an increased use of spatial data in mobile devices - thus enabling, together...... with the rapidly evolving positioning techniques, a new category of position-dependent, map-based services to be introduced. The report consists of the following parts: Part I: Categorization of handheld devices, Part II: Cartographic design for small-display devices, Part III: Study on the GiMoDig Client ? Portal...... Service Communication and finally, Part IV: Concluding remarks and topics for further research on small-display cartography. Part II includes a separate Appendix D consisting of a cartographic design specification. Part III includes a separate Appendix C consisting of a schema specification, a separate...

  20. Flexible displays, rigid designs?

    DEFF Research Database (Denmark)

    Hornbæk, Kasper


    Rapid technological progress has enabled a wide range of flexible displays for computing devices, but the user experience--which we're only beginning to understand--will be the key driver for successful designs....

  1. Monocular display unit for 3D display with correct depth perception (United States)

    Sakamoto, Kunio; Hosomi, Takashi


    A study of virtual-reality system has been popular and its technology has been applied to medical engineering, educational engineering, a CAD/CAM system and so on. The 3D imaging display system has two types in the presentation method; one is a 3-D display system using a special glasses and the other is the monitor system requiring no special glasses. A liquid crystal display (LCD) recently comes into common use. It is possible for this display unit to provide the same size of displaying area as the image screen on the panel. A display system requiring no special glasses is useful for a 3D TV monitor, but this system has demerit such that the size of a monitor restricts the visual field for displaying images. Thus the conventional display can show only one screen, but it is impossible to enlarge the size of a screen, for example twice. To enlarge the display area, the authors have developed an enlarging method of display area using a mirror. Our extension method enables the observers to show the virtual image plane and to enlarge a screen area twice. In the developed display unit, we made use of an image separating technique using polarized glasses, a parallax barrier or a lenticular lens screen for 3D imaging. The mirror can generate the virtual image plane and it enlarges a screen area twice. Meanwhile the 3D display system using special glasses can also display virtual images over a wide area. In this paper, we present a monocular 3D vision system with accommodation mechanism, which is useful function for perceiving depth.

  2. Military display performance parameters (United States)

    Desjardins, Daniel D.; Meyer, Frederick


    The military display market is analyzed in terms of four of its segments: avionics, vetronics, dismounted soldier, and command and control. Requirements are summarized for a number of technology-driving parameters, to include luminance, night vision imaging system compatibility, gray levels, resolution, dimming range, viewing angle, video capability, altitude, temperature, shock and vibration, etc., for direct-view and virtual-view displays in cockpits and crew stations. Technical specifications are discussed for selected programs.

  3. Raster graphics display library (United States)

    Grimsrud, Anders; Stephenson, Michael B.


    The Raster Graphics Display Library (RGDL) is a high level subroutine package that give the advanced raster graphics display capabilities needed. The RGDL uses FORTRAN source code routines to build subroutines modular enough to use as stand-alone routines in a black box type of environment. Six examples are presented which will teach the use of RGDL in the fastest, most complete way possible. Routines within the display library that are used to produce raster graphics are presented in alphabetical order, each on a separate page. Each user-callable routine is described by function and calling parameters. All common blocks that are used in the display library are listed and the use of each variable within each common block is discussed. A reference on the include files that are necessary to compile the display library is contained. Each include file and its purpose are listed. The link map for MOVIE.BYU version 6, a general purpose computer graphics display system that uses RGDL software, is also contained.

  4. Display measuring system СМ-100 for LCD characterization

    Directory of Open Access Journals (Sweden)

    V. M. Sorokin


    Full Text Available Creation of new liquid crystal displays and their adaptation for different external environments are impossible without correct diagnosing of wide range of electro-optical effects inherent to nematic, smectic and cholesteric liquid crystal materials. The modern universal display measuring complexes allow to solve this problem. Among different display measuring complexes those are wide used in the world for scientific centers and enterprises in Russia, Belorussia and Ukraine the complex CM-100, which has been developed in Institute of Semiconductor Phisics of NAS of Ukraine, is the most suitable.

  5. Efficient display of active Geotrichum sp. lipase on Pichia pastoris cell wall and its application as a whole-cell biocatalyst to enrich EPA and DHA in fish oil. (United States)

    Pan, Xiao-Xing; Xu, Li; Zhang, Yan; Xiao, Xiao; Wang, Xiao-Feng; Liu, Yun; Zhang, Hou-jin; Yan, Yun-Jun


    Geotrichum sp. lipase (GSL) was first displayed on the cell wall of Pichia pastoris on the basis of the a-agglutinin anchor system developed in Saccharomyces cerevisiae . Surface display levels were monitored using Western blotting, immunofluorescence miscroscopy, and fluorescence-activated cell sorting analysis. Lipase activity of the yeast whole cells reached a maximum at 273 ± 2.4 U/g of dry cells toward olive oil after 96 h of culture at 30 °C, with optimal pH and temperature at 7.5 and 45 °C, respectively. Displayed GSL exhibited relatively high stability between pH 6.0 and 8.0 and retained >70% of the maximum activity. The surface-displayed lipase retained 80% of its original activity after incubation at 45 °C for 4 h. Moreover, the GSL-displaying yeast whole cells were then used as a biocatalyst to enrich eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil on the basis of selective hydrolysis. As a result, EPA and DHA increased from 1.53 and 24.1% in the original fish oil to 1.85 and 30.86%, which were increases of 1.21- and 1.29-fold, respectively. The total yield of EPA and DHA reached 46.62%.

  6. Efficiency of various lattices from hard ball to soft ball: theoretical study of thermodynamic properties of dendrimer liquid crystal from atomistic simulation. (United States)

    Li, Youyong; Lin, Shiang-Tai; Goddard, William A


    Self-assembled supramolecular organic liquid crystal structures at nanoscale have potential applications in molecular electronics, photonics, and porous nanomaterials. Most of these structures are formed by aggregation of soft spherical supramolecules, which have soft coronas and overlap each other in the packing process. Our main focus here is to study the possible packing mechanisms via molecular dynamics simulations at the atomistic level. We consider the relative stability of various lattices packed by the soft dendrimer balls, first synthesized and characterized by Percec et al. (J. Am. Chem. Soc. 1997, 119, 1539) with different packing methods. The dendrons, which form the soft dendrimer balls, have the character of a hard aromatic region from the point of the cone to the edge with C(12) alkane "hair". After the dendrons pack into a sphere, the core of the sphere has the hard aromatic groups, while the surface is covered with the C(12) alkane "hair". In our studies, we propose three ways to organize the hair on the balls, Smooth/Valentino balls, Sticky/Einstein balls, and Asymmetric/Punk balls, which lead to three different packing mechanisms, Slippery, Sticky, and Anisotropic, respectively. We carry out a series of molecular dynamics (MD) studies on three plausible crystal structures (A15, FCC, and BCC) as a function of density and analyze the MD based on the vibrational density of state (DoS) method to extract the enthalpy, entropy, and free energies of these systems. We find that anisotropic packed A15 is favored over FCC, BCC lattices. Our predicted X-ray intensities of the best structures are in excellent agreement with experiment. "Anisotropic ball packing" proposed here plays an intermediate role between the enthalpy-favored "disk packing" and entropy-favored "isotropic ball packing", which explains the phase transitions at different temperatures. Free energies of various lattices at different densities are essentially the same, indicating that the

  7. Light Emitting Transistors of Organic Single Crystals (United States)

    Iwasa, Yoshihiro


    Organic light emitting transistors (OLETs) are attracting considerable interest as a novel function of organic field effect transistors (OFETs). Besides a smallest integration of light source and current switching devices, OLETs offer a new opportunity in the fundamental research on organic light emitting devices. The OLET device structure allows us to use organic single crystals, in contrast to the organic light emitting diodes (OLEDs), the research of which have been conducted predominantly on polycrystalline or amorphous thin films. In the case of OFETs, use of single crystals have produced a significant amount of benefits in the studies of pursuit for the highest performance limit of FETs, intrinsic transport mechanism in organic semiconductors, and application of the single crystal transistors. The study on OLETs have been made predominantly on polycrystalline films or multicomponent heterojunctions, and single crystal study is still limited to tetracene [1] and rubrene [2], which are materials with relatively high mobility, but with low photoluminescence efficiency. In this paper, we report fabrication of single crystal OLETs of several kinds of highly luminescent molecules, emitting colorful light, ranging from blue to red. Our strategy is single crystallization of monomeric or oligomeric molecules, which are known to have a very high photoluminescence efficiency. Here we report the result on single crystal LETs of rubrene (red), 4,4'-bis(diphenylvinylenyl)-anthracene (green), 1,4-bis(5-phenylthiophene-2-yl)benzene (AC5) (green), and 1,3,6,8-tetraphenylpyrene (TPPy) (blue), all of which displayed ambipolar transport as well as peculiar movement of voltage controlled movement of recombination zone, not only from the surface of the crystal but also from the edges of the crystals, indicting light confinement inside the crystal. Realization of ambipolar OLET with variety of single crystals indicates that the fabrication method is quite versatile to various light

  8. 3D液晶显示模组不均匀分区背光扫描及其设计方法%Shutter glass type of 3D liquid crystal display module non-uniform partition scanning backlight and its design method based on

    Institute of Scientific and Technical Information of China (English)



    With the rapid development of liquid crystal display technology, 3D display gradually sought after the market and consumers. In the 3D LCD TV, there is a kind of shutter type 3D display technology. This technique also shot the same object's left and right eyes two pictures by two cameras at certain intervals, and synthetic treatment, on the display screen through time-sharing display out, then match the shutter glasses with the same time frequency, the same object images to the left and the right eyes respectively to watch camera captured. As the two pictures there is disparity is different, the human eye can feel the stereo image, realize 3D display effect. In order to achieve better 3D display effect, generally control the scanning backlight system through mode of backlight.%随着液晶显示技术的快速发展,3D液晶显示逐渐受到市场和消费者的追捧。在3D液晶电视中,有一类快门式3D显示技术。这种技术通过一定间隔的两台摄像机同时拍摄同一个物体的左右眼两幅画面,然后合成处理后,在显示屏上通过分时显示的方式显示出来,然后搭配与分时频率相同的快门式眼镜,使人的左右眼分别观看到摄像机拍摄到的同一物体画面。由于两幅画面存在视差的不同,人眼即可感受到了立体的影像,实现3D效果显示。为了实现更好的3D显示效果,一般通过扫描背光的方式来对背光系统进行控制。

  9. Modern Display Technologies for Airborne Applications. (United States)


    from the sulphonic acid group and achieved operating life of greater than 10’ cycles with over 3 years shelf-life. The switching speed was rather slow...pitch. In spite of all this ordering, however, liquid crystals are clearly liquid, flowing readily with quite low viscosity . Consequently the...solids and is the basis of most optical effects used in displays. Other physical properties, such as electrical conductivity, elasticity, viscosity

  10. From optical MEMS to photonic crystal (United States)

    Lee, Sukhan; Kim, Jideog; Lee, Hong-Seok; Moon, Il-Kwon; Won, JongHwa; Ku, Janam; Choi, Hyung; Shin, Hyungjae


    This paper presents the emergence of photonic crystals as significant optomechatronics components, following optical MEMS. It is predicted that, in the coming years, optical MEMS and photonic crystals may go through dynamic interactions leading to synergy as well as competition. First, we present the Structured Defect Photonic Crystal (SDPCTM) devised by the authors for providing the freedom of designing photonic bandgap structures, such that the application of photonic crystals be greatly extended. Then, we present the applications of optical MEMS and photonic crystals to displays and telecommunications. It is shown that many of the applications that optical MEMS can contribute to telecommunications and displays may be implemented by photonic crystals.

  11. Ergonomic concerns with lightbar guidance displays. (United States)

    Ima, C S; Mann, D D


    This article reviews some ergonomic factors associated with agricultural guidance displays. Any technology or management decision that improves the efficiency of an agricultural operation can be considered an aspect of precision farming. Agricultural guidance displays are one such tool because they help to reduce guidance error (i.e., skipping and overlapping of implements within the field), which result in improper application of crop inputs at increased cost. Although each of the guidance displays currently available functions using a different principle, their key objective is to communicate useful guidance information to the operator of the agricultural machine. The case with which the operator obtains the required information depends on a number of ergonomic factors, such as color perceptibility, flash rate, attentional demand, display size, viewing distance, and height of placement of the display in the cab. Ergonomics can be defined as the application of knowledge to create a safe, comfortable, and effective work environment. Consequently, it is critical to consider ergonomics when designing guidance displays or when locating a display in the tractor cab. Without considering ergonomics, it is unlikely that the efficiency of the human-machine system can be optimized.

  12. Dynamic plasmonic colour display (United States)

    Duan, Xiaoyang; Kamin, Simon; Liu, Na


    Plasmonic colour printing based on engineered metasurfaces has revolutionized colour display science due to its unprecedented subwavelength resolution and high-density optical data storage. However, advanced plasmonic displays with novel functionalities including dynamic multicolour printing, animations, and highly secure encryption have remained in their infancy. Here we demonstrate a dynamic plasmonic colour display technique that enables all the aforementioned functionalities using catalytic magnesium metasurfaces. Controlled hydrogenation and dehydrogenation of the constituent magnesium nanoparticles, which serve as dynamic pixels, allow for plasmonic colour printing, tuning, erasing and restoration of colour. Different dynamic pixels feature distinct colour transformation kinetics, enabling plasmonic animations. Through smart material processing, information encoded on selected pixels, which are indiscernible to both optical and scanning electron microscopies, can only be read out using hydrogen as a decoding key, suggesting a new generation of information encryption and anti-counterfeiting applications.

  13. The Ultimate Display

    CERN Document Server

    Fluke, C J


    Astronomical images and datasets are increasingly high-resolution and multi-dimensional. The vast majority of astronomers perform all of their visualisation and analysis tasks on low-resolution, two-dimensional desktop monitors. If there were no technological barriers to designing the ultimate stereoscopic display for astronomy, what would it look like? What capabilities would we require of our compute hardware to drive it? And are existing technologies even close to providing a true 3D experience that is compatible with the depth resolution of human stereoscopic vision? We consider the CAVE2 (an 80 Megapixel, hybrid 2D and 3D virtual reality environment directly integrated with a 100 Tflop/s GPU-powered supercomputer) and the Oculus Rift (a low- cost, head-mounted display) as examples at opposite financial ends of the immersive display spectrum.

  14. Purification of 5-hydroxymethylfurfural (hmf) by crystallization

    DEFF Research Database (Denmark)


    This invention relates to an efficient procedure for purifying HMF by crystallization at low temperature from an organic solvent.......This invention relates to an efficient procedure for purifying HMF by crystallization at low temperature from an organic solvent....

  15. Automated High Throughput Protein Crystallization Screening at Nanoliter Scale and Protein Structural Study on Lactate Dehydrogenase

    Energy Technology Data Exchange (ETDEWEB)

    Li, Fenglei [Iowa State Univ., Ames, IA (United States)


    The purposes of our research were: (1) To develop an economical, easy to use, automated, high throughput system for large scale protein crystallization screening. (2) To develop a new protein crystallization method with high screening efficiency, low protein consumption and complete compatibility with high throughput screening system. (3) To determine the structure of lactate dehydrogenase complexed with NADH by x-ray protein crystallography to study its inherent structural properties. Firstly, we demonstrated large scale protein crystallization screening can be performed in a high throughput manner with low cost, easy operation. The overall system integrates liquid dispensing, crystallization and detection and serves as a whole solution to protein crystallization screening. The system can dispense protein and multiple different precipitants in nanoliter scale and in parallel. A new detection scheme, native fluorescence, has been developed in this system to form a two-detector system with a visible light detector for detecting protein crystallization screening results. This detection scheme has capability of eliminating common false positives by distinguishing protein crystals from inorganic crystals in a high throughput and non-destructive manner. The entire system from liquid dispensing, crystallization to crystal detection is essentially parallel, high throughput and compatible with automation. The system was successfully demonstrated by lysozyme crystallization screening. Secondly, we developed a new crystallization method with high screening efficiency, low protein consumption and compatibility with automation and high throughput. In this crystallization method, a gas permeable membrane is employed to achieve the gentle evaporation required by protein crystallization. Protein consumption is significantly reduced to nanoliter scale for each condition and thus permits exploring more conditions in a phase diagram for given amount of protein. In addition

  16. Analysing the effect of crystal size and structure in highly efficient CH3NH3PbI3 perovskite solar cells by spatially resolved photo- and electroluminescence imaging. (United States)

    Mastroianni, S; Heinz, F D; Im, J-H; Veurman, W; Padilla, M; Schubert, M C; Würfel, U; Grätzel, M; Park, N-G; Hinsch, A


    CH3NH3PbI3 perovskite solar cells with a mesoporous TiO2 layer and spiro-MeOTAD as a hole transport layer (HTL) with three different CH3NH3I concentrations (0.032 M, 0.044 M and 0.063 M) were investigated. Strong variations in crystal size and morphology resulting in diversified cell efficiencies (9.2%, 16.9% and 12.3%, respectively) were observed. The physical origin of this behaviour was analysed by detailed characterization combining current-voltage curves with photo- and electroluminescence (PL and EL) imaging as well as light beam induced current measurements (LBIC). It was found that the most efficient cell shows the highest luminescence and the least efficient cell is most strongly limited by non-radiative recombination. Crystal size, morphology and distribution in the capping layer and in the porous scaffold strongly affect the non-radiative recombination. Moreover, the very non-uniform crystal structure with multiple facets, as evidenced by SEM images of the 0.032 M device, suggests the creation of a large number of grain boundaries and crystal dislocations. These defects give rise to increased trap-assisted non-radiative recombination as is confirmed by high-resolution μ-PL images. The different imaging techniques used in this study prove to be well-suited to spatially investigate and thus correlate the crystal morphology of the perovskite layer with the electrical and radiative properties of the solar cells and thus with their performance.

  17. Metal-induced crystallization fundamentals and applications

    CERN Document Server

    Wang, Zumin; Mittemeijer, Eric J


    Introduction to Metal-Induced CrystallizationAtomic Mechanisms and Interface Thermodynamics of Metal-Induced Crystallization of Amorphous Semiconductors at Low TemperaturesThermodynamics and Kinetics of Layer Exchange upon Low-Temperature Annealing Amorphous Si/Polycrystalline Al Layered StructuresMetal-Induced Crystallization by Homogeneous Insertion of Metallic Species in Amorphous SemiconductorsAluminum-Induced Crystallization: Applications in Photovoltaic TechnologiesApplications of Metal-Induced Crystallization for Advanced Flat-Panel DisplaysLaser-Assisted Meta

  18. Refreshing Refreshable Braille Displays. (United States)

    Russomanno, Alexander; O'Modhrain, Sile; Gillespie, R Brent; Rodger, Matthew W M


    The increased access to books afforded to blind people via e-publishing has given them long-sought independence for both recreational and educational reading. In most cases, blind readers access materials using speech output. For some content such as highly technical texts, music, and graphics, speech is not an appropriate access modality as it does not promote deep understanding. Therefore blind braille readers often prefer electronic braille displays. But, these are prohibitively expensive. The search is on, therefore, for a low-cost refreshable display that would go beyond current technologies and deliver graphical content as well as text. And many solutions have been proposed, some of which reduce costs by restricting the number of characters that can be displayed, even down to a single braille cell. In this paper, we demonstrate that restricting tactile cues during braille reading leads to poorer performance in a letter recognition task. In particular, we show that lack of sliding contact between the fingertip and the braille reading surface results in more errors and that the number of errors increases as a function of presentation speed. These findings suggest that single cell displays which do not incorporate sliding contact are likely to be less effective for braille reading.

  19. Virtual Auditory Displays (United States)


    timbre , intensity, distance, room modeling, radio communication Virtual Environments Handbook Chapter 4 Virtual Auditory Displays Russell D... musical note “A” as a pure sinusoid, there will be 440 condensations and rarefactions per second. The distance between two adjacent condensations or...and complexity are pitch, loudness, and timbre respectively. This distinction between physical and perceptual measures of sound properties is an

  20. Virtual acoustic displays (United States)

    Wenzel, Elizabeth M.


    A 3D auditory display can potentially enhance information transfer by combining directional and iconic information in a quite naturalistic representation of dynamic objects in the interface. Another aspect of auditory spatial clues is that, in conjunction with other modalities, it can act as a potentiator of information in the display. For example, visual and auditory cues together can reinforce the information content of the display and provide a greater sense of presence or realism in a manner not readily achievable by either modality alone. This phenomenon will be particularly useful in telepresence applications, such as advanced teleconferencing environments, shared electronic workspaces, and monitoring telerobotic activities in remote or hazardous situations. Thus, the combination of direct spatial cues with good principles of iconic design could provide an extremely powerful and information-rich display which is also quite easy to use. An alternative approach, recently developed at ARC, generates externalized, 3D sound cues over headphones in realtime using digital signal processing. Here, the synthesis technique involves the digital generation of stimuli using Head-Related Transfer Functions (HRTF's) measured in the two ear-canals of individual subjects. Other similar approaches include an analog system developed by Loomis, et. al., (1990) and digital systems which make use of transforms derived from normative mannikins and simulations of room acoustics. Such an interface also requires the careful psychophysical evaluation of listener's ability to accurately localize the virtual or synthetic sound sources. From an applied standpoint, measurement of each potential listener's HRTF's may not be possible in practice. For experienced listeners, localization performance was only slightly degraded compared to a subject's inherent ability. Alternatively, even inexperienced listeners may be able to adapt to a particular set of HRTF's as long as they provide adequate

  1. Investigation on structural, optical, thermal, mechanical and dielectric properties of L-proline cadmium chloride monohydrate single crystals: An efficient NLO material

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Preeti; Hasmuddin, Mohd [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110 025 (India); Shakir, Mohd [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110 025 (India); CSIR-National Physical Laboratory, New Delhi 110 012 (India); Department of Physics, ARSD College, University of Delhi, New Delhi 110021 (India); Vijayan, N. [Department of Physics, Kakatiya University, Warangal 506 009 (India); Abdullah, M.M. [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110 025 (India); Advanced Materials and Nano-research Centre (AMNC), Faculty of Science and Arts, Najran University, P.O. Box-1988, Najran 11001 (Saudi Arabia); Ganesh, V. [Department of Physics, Kakatiya University, Warangal 506 009 (India); Wahab, M.A., E-mail: [Crystal Growth and XRD Lab, Department of Physics, Jamia Millia Islamia, New Delhi 110 025 (India)


    In the present work, we have grown single crystals of L-proline cadmium chloride monohydrate (LPCCM) by slow evaporation solution technique (SEST) at room temperature and recorded their live growth kinetics with the help of inverted microscope. Crystal size at various stages of growth and its corresponding morphology was also recorded. Powder X-ray diffraction (PXRD) analysis of LPCCM single crystals confirmed the orthorhombic structure. Respective values of crystallite size, strain and dislocation density have been calculated using PXRD data. Metal complex coordination of the single crystal is studied by FTIR spectroscopic. The optical properties of the grown crystals were investigated through UV–VIS spectroscopic studies and shows that the crystals have very low absorption in entire characterized wavelength range 200–800 nm. The optical band gap was calculated and found to be ∼5.6 eV. Optical constants of the material is determined by theoretical calculations. The chemical etching study was also carried out to study the density of defects in the grown crystals. The photoluminous excitation and emission spectra and thermal property by TGA/DTA curve were recorded. Further, the mechanical properties have been studied using Vicker's microhardness tester as well as many parameters such as fracture toughness (K{sub c}), Brittleness index (B{sub i}) and yield strength (σ{sub ν}) are presented. Dielectric studies have been carried out with varying frequency and temperatures. - Highlights: • The morphology of LPCCM crystal was observed during growth under inverted microscope. • Observation also shows defects also grows with the growth of crystal. • Positive temperature coefficient is observed. • The optical study shows its suitability for photonics and optical applications.

  2. Steerable patterned OLED backlight for autostereoscopic display application (United States)

    Vogel, Uwe; Fehse, Karsten; Wartenberg, Philipp; Knobbe, Jens; Scholles, Michael; Richter, Bernd; Hild, Olaf


    OLED can be applied as highly efficient and high-resolution patternable illumination source for controllable and steerable backlights, e.g., for use in autostereoscopic displays. To evaluate technology and approach a 3.5" 3D QVGA display prototype has been developed and combines several achievements: large-area OLED backlight, highly-efficient and fast-response OLED top-emitter, striped patterned backlight, individual electronic driving for adaptive backlight control and 3D mobile display application.

  3. Etching efficiency of tracks differently oriented with respect to the symmetry axis of a crystal lattice of olivine monocrystals from Marjalahti pallasite

    Energy Technology Data Exchange (ETDEWEB)

    Bagulya, A.V.; Goncharova, L.A. [Lebedev Physical Institute, Russian Academy of Sciences, Leninskii pr., 53, Moscow 119991 (Russian Federation); Ivliev, A.I., E-mail: cosmo@geokhi.r [Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygina str., 19, 119991 (Russian Federation); Kalinina, G.V., E-mail: ugeochem@geochem.home.chg.r [Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygina str., 19, 119991 (Russian Federation); Kashkarov, L.L. [Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygina str., 19, 119991 (Russian Federation); Konovalova, N.S.; Okat' eva, N.M. [Lebedev Physical Institute, Russian Academy of Sciences, Leninskii pr., 53, Moscow 119991 (Russian Federation); Polukhina, N.G., E-mail: poluhina@sci.lebedev.r [Lebedev Physical Institute, Russian Academy of Sciences, Leninskii pr., 53, Moscow 119991 (Russian Federation); Roussetski, A.S.; Starkov, N.I.; Tsarev, V.A. [Lebedev Physical Institute, Russian Academy of Sciences, Leninskii pr., 53, Moscow 119991 (Russian Federation); Vladymyrov, M.S., E-mail: neworld@itep.r [Lebedev Physical Institute, Russian Academy of Sciences, Leninskii pr., 53, Moscow 119991 (Russian Federation)


    The results of measurements of the major track parameters for tracks formed by the accelerated {sup 131}Xe (E = 1.5 GeV) nuclei in individual olivine grains from the Marjalahti pallasite are presented. For each of ten treated crystals, the structure and the main crystal lattice symmetry axis were determined by the X-ray diffraction analysis. The basic track parameters (etching rate V{sub TR} and etched length L) were shown to be independent of the angle between the monocrystal main symmetry axis for each examined crystal and the direction of the accelerated nucleus beam.

  4. Determination of the Er{sup 3+} to Yb{sup 3+} energy transfer efficiency in Er{sup 3+}/Yb{sup 3+}-codoped YVO{sub 4} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Di Paolo, R.E. [Departamento de Fisica de Materiales, C-IV, Universidad Autonoma de Madrid, Madrid (Spain); Centro de Investigaciones Opticas (CIOp), CC 124, La Plata (Argentina); Cantelar, E.; Cusso, F. [Departamento de Fisica de Materiales, C-IV, Universidad Autonoma de Madrid, Madrid (Spain)]. E-mail:; Wang, X.M. [Institute of Physics, Chinese Academy of Sciences, Beijing (China); Tsuboi, T. [Faculty of Engineering, Kyoto Sangyo University, Kamigamo, Kita-ku, Kyoto (Japan)


    The energy transfer efficiency from Er{sup 3+} to Yb{sup 3+} ions in yttrium orthovanadate single crystals (YVO{sub 4}) is experimentally obtained, by using a method based on the simultaneous and multiwavelength measurement of photoacoustic and luminescent signals after pulsed laser excitation. The result is reached by comparing with the predictions from Judd-Ofelt analysis and the lifetime measurements. The energy transfer between the ions, from Er{sup 3+} to Yb{sup 3+}, must be considered in order to fit the experimental results. A value of energy transfer efficiency ({psi}=0.16) is obtained. (author)

  5. A crystal barrel

    CERN Multimedia


    The production of crystals for the barrel of the CMS electromagnetic calorimeter has been completed. This is an important milestone for the experiment, which received the last of its 62,960 crystals on 9 March. The members of the team responsible for the crystal acceptance testing at CERN display the last crystal for the CMS electromagnetic calorimeter barrel. From left to right: Igor Tarasov, Etiennette Auffray and Hervé Cornet.One of the six machines specially developed to measure 67 different parameters on each crystal. Igor Tarasov is seen inserting the last batch of crystals into the machine. The last of the 62,960 CMS barrel crystals arrived at CERN on 9 March. Once removed from its polystyrene protection, this delicate crystal, like thousands of its predecessors, will be inserted into the last of the 36 supermodules of the barrel electromagnetic calorimeter in a few days' time. This marks the end of an important chapter in an almost 15-year-long journey by the CMS crystals team, some of whose member...

  6. Efficient broad color luminescence from InGaN/GaN single quantum-well nanocolumn crystals on Si (111) substrate (United States)

    Zhang, Wei; Zhang, Xuehua; Wang, Yongjin; Hu, Fangren


    Nanocolumn InGaN/GaN single quantum well crystals were deposited on Si (111) substrate with nitrified Ga dots as buffer layer. Transmission electron microscopy image shows the crystals' diameter of 100-130 nm and length of about 900 nm. Nanoscale spatial phase separation of cubic and hexagonal GaN was observed by selective area electron diffraction on the quantum well layer. Raman spectrum of the quantum well crystals proved that the crystals were fully relaxed. Room temperature photoluminescence from 450 to 750 nm and full width at half maximum of about 420 meV indicate broad color luminescence covering blue, green, yellow and red emission, which is helpful for the fabrication of tunable optoelectronic devices and colorful light emitting diodes.

  7. Image Descriptors for Displays (United States)


    hypothetical televison display. The viewing distance is 4 picture heights, and the bandwidth limitation has been set by the U.S. Monochrome Standards...significantly influence the power spectrum over most of the video frequency range. A large dc component and a small random component provide another scene... influences . It was Illuminated with natural light to a brightness of over 300 ft-L. The high brightness levels were chosen so as to nearly reproduce the

  8. Refrigerated display cabinets; Butikskyla

    Energy Technology Data Exchange (ETDEWEB)

    Fahlen, Per


    This report summarizes experience from SP research and assignments regarding refrigerated transport and storage of food, mainly in the retail sector. It presents the fundamentals of heat and mass transfer in display cabinets with special focus on indirect systems and secondary refrigerants. Moreover, the report includes a brief account of basic food hygiene and the related regulations. The material has been compiled for educational purposes in the Masters program at Chalmers Technical University.

  9. Efficient Coupling and Transport of a Surface Plasmon at 780 nm in a Gold Nanostructure

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Yu; Joly, Alan G.; El-Khoury, Patrick Z.; Hess, Wayne P.


    We studied plasmonic nanostructures in single-crystal gold with scanning electron and femtosecond photoemission electron microscopies. We designed an integrated laser coupling and nanowire waveguide structure by focused ion beam lithography in single-crystal gold flakes. The photoemission results show that the laser field is efficiently coupled into a propagating surface plasmon by a simple hole structure and propagates efficiently in an adjacent nano-bar waveguide. A strong local field is created by the propagating surface plasmon at the nano-bar tip. A similar structure, with a decreased waveguide width and thickness, displayed significantly more intense photoemission indicating enhanced local electric field at the sharper tip.

  10. Market trends in the projection display industry (United States)

    Dash, Sweta


    The projection display industry represents a multibillion- dollar market that includes four distinct technologies. High-volume consumer products and high-value business products drive the market, with different technologies being used in different application markets. The consumer market is dominated by rear CRT technology, especially in the projection TV segment. Rear LCD (liquid crystal display), MEMS/DLP (or Digital Light Processing TM) and LCOS (Liquid-crystal-on-silicon) TVs are slowly emerging as future competitors to rear CRT projectors. Front CRT projectors are also facing challenges from LCD and DLP technology for the home theater market while the business market is completely dominated by front LCD and DLP technology. Three-chip DLP projectors have replaced liquid crystal light valves in large venue applications where projectors have higher light output requirements. In recent years front LCD and LCOS projectors have been increasingly competing with 3-chip DLP projectors especially at the low end of the large venue application market. Within the next five years the projection market will experience very fast growth. Sales and presentation applications, which are the fastest growing applications in the business market, will continue to be the major driving force for the growth for front projectors, and the shift in the consumer market to digital and HDTV products will drive the rear projection market.

  11. Book Display as Adult Service

    Directory of Open Access Journals (Sweden)

    Matthew S. Moore


    Full Text Available 無Book display as an adult service is defined as choosing and positioning adult books from the collection to increase their circulation. The author contrasts bookstore arrangement for sales versus library arrangement for access. The paper considers the library-as-a-whole as a display, examines the right size for an in-library display, and discusses mass displays, end-caps, on-shelf displays, and the Tiffany approach. The author proposes that an effective display depends on an imaginative, unifying theme, and that book displays are part of the joy of libraries.

  12. Handbook of Visual Display Technology

    CERN Document Server

    Cranton, Wayne; Fihn, Mark


    The Handbook of Visual Display Technology is a unique work offering a comprehensive description of the science, technology, economic and human interface factors associated with the displays industry. An invaluable compilation of information, the Handbook will serve as a single reference source with expert contributions from over 150 international display professionals and academic researchers. All classes of display device are covered including LCDs, reflective displays, flexible solutions and emissive devices such as OLEDs and plasma displays, with discussion of established principles, emergent technologies, and particular areas of application. The wide-ranging content also encompasses the fundamental science of light and vision, image manipulation, core materials and processing techniques, display driving and metrology.

  13. 双稳态显示的一种新型低功耗高压驱动%A New Power-Efficient High-Voltage Driver for Bistable Displays

    Institute of Scientific and Technical Information of China (English)

    Ann Monté; Jan Doutreloigne; André Van Calster


    A big problem in portable applications like e-books and pda's (personal digital assistant) is the lifetime of the batteries. The power consumption of the battery is determined by the processing of the ap-paratus on one hand and by the driver of its display on the other hand. A reduction of the power consump-tion can be achieved by optimizing the display driver. It will be proved that the energy consumed by the driver can be reduced for 50% by designing an intelligent driver that calculates the row and column wave-forms for every image based on the several energy-saving principles.%电池的使用寿命不够长是电子书、PDA 等之类的便携式显示应用的一个重大问题.电池的功耗一方面取决于其制作工艺,另一方面还与显示器的驱动有关.优化显示器的驱动可以降低其功耗.文章介绍了一种智能型驱动,通过对其每个图像的行列波的计算可知其功耗降低了 50%.

  14. Plasmonic gold nanocrystals coupled with photonic crystal seamlessly on TiO2 nanotube photoelectrodes for efficient visible light photoelectrochemical water splitting

    KAUST Repository

    Zhang, Zhonghai


    A visible light responsive plasmonic photocatalytic composite material is designed by rationally selecting Au nanocrystals and assembling them with the TiO2-based photonic crystal substrate. The selection of the Au nanocrystals is so that their surface plasmonic resonance (SPR) wavelength matches the photonic band gap of the photonic crystal and thus that the SPR of the Au receives remarkable assistance from the photonic crystal substrate. The design of the composite material is expected to significantly increase the Au SPR intensity and consequently boost the hot electron injection from the Au nanocrystals into the conduction band of TiO2, leading to a considerably enhanced water splitting performance of the material under visible light. A proof-of-concept example is provided by assembling 20 nm Au nanocrystals, with a SPR peak at 556 nm, onto the photonic crystal which is seamlessly connected on TiO2 nanotube array. Under visible light illumination (>420 nm), the designed material produced a photocurrent density of ∼150 μA cm-2, which is the highest value ever reported in any plasmonic Au/TiO2 system under visible light irradiation due to the photonic crystal-assisted SPR. This work contributes to the rational design of the visible light responsive plasmonic photocatalytic composite material based on wide band gap metal oxides for photoelectrochemical applications. © 2012 American Chemical Society.

  15. Crystals in crystals

    DEFF Research Database (Denmark)

    Christensen, Claus H.; Schmidt, I.; Carlsson, A.;


    A major factor governing the performance of catalytically active particles supported on a zeolite carrier is the degree of dispersion. It is shown that the introduction of noncrystallographic mesopores into zeolite single crystals (silicalite-1, ZSM-5) may increase the degree of particle dispersion...... of the zeolite particles, particularly after thermal treatment. When using mesoporous zeolites, the particles were evenly distributed throughout the mesopore system of the zeolitic support, even after calcination, leading to nanocrystals within mesoporous zeolite single crystals....

  16. Technologies and solutions for data display in the operating room. (United States)

    Bitterman, Noemi


    Recent advances in technology have led to the introduction of a variety of innovative devices, each with their own platform for data display, into the operating room (OR). While these innovative applications are expanding the traditional boundaries of the surgical space and enhancing treatment capabilities, the introduction of additional screens and displays is placing an ever-increasing load on the OR team. This review describes the main data display platforms currently available in ORs: computer monitors with CRT (cathode ray tube) or LCD (liquid crystal display) screens, suspended imaging displays, wearable computers (WC), auditory displays and tactile (haptic) displays. The different display platforms are evaluated according to their compatibility with the characteristics of the working environment (OR), the monitoring task, and the users (the surgical team). No single display configuration provides an ultimate solution for presenting patient data in the OR. A multi-sensory data display including visual, acoustic and haptic manipulation is suggested as a promising configuration for data display in the OR.

  17. Navigational Heads-Up Display: Will a Shipboard Augmented Electronic Navigation System Sink or Swim? (United States)


    76 Table 6. Subject Video Game Practice...Interface GPS Global Positioning System HMD Head-Mounted Display HUD Heads-Up Display IP Internet Protocol IR Infrared LCD Liquid-Crystal Display...Stress Disorder SDK Software Development Kit SOG Speed over Ground SWOS Surface Warfare Officer School USD United States Dollar USNS United States

  18. Methods and apparatus for transparent display using scattering nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Chia Wei; Qiu, Wenjun; Zhen, Bo; Shapira, Ofer; Soljacic, Marin


    Transparent displays enable many useful applications, including heads-up displays for cars and aircraft as well as displays on eyeglasses and glass windows. Unfortunately, transparent displays made of organic light-emitting diodes are typically expensive and opaque. Heads-up displays often require fixed light sources and have limited viewing angles. And transparent displays that use frequency conversion are typically energy inefficient. Conversely, the present transparent displays operate by scattering visible light from resonant nanoparticles with narrowband scattering cross sections and small absorption cross sections. More specifically, projecting an image onto a transparent screen doped with nanoparticles that selectively scatter light at the image wavelength(s) yields an image on the screen visible to an observer. Because the nanoparticles scatter light at only certain wavelengths, the screen is practically transparent under ambient light. Exemplary transparent scattering displays can be simple, inexpensive, scalable to large sizes, viewable over wide angular ranges, energy efficient, and transparent simultaneously.

  19. Methods and apparatus for transparent display using scattering nanoparticles (United States)

    Hsu, Chia Wei; Qiu, Wenjun; Zhen, Bo; Shapira, Ofer; Soljacic, Marin


    Transparent displays enable many useful applications, including heads-up displays for cars and aircraft as well as displays on eyeglasses and glass windows. Unfortunately, transparent displays made of organic light-emitting diodes are typically expensive and opaque. Heads-up displays often require fixed light sources and have limited viewing angles. And transparent displays that use frequency conversion are typically energy inefficient. Conversely, the present transparent displays operate by scattering visible light from resonant nanoparticles with narrowband scattering cross sections and small absorption cross sections. More specifically, projecting an image onto a transparent screen doped with nanoparticles that selectively scatter light at the image wavelength(s) yields an image on the screen visible to an observer. Because the nanoparticles scatter light at only certain wavelengths, the screen is practically transparent under ambient light. Exemplary transparent scattering displays can be simple, inexpensive, scalable to large sizes, viewable over wide angular ranges, energy efficient, and transparent simultaneously.

  20. Efficient biological conversion of carbon monoxide (CO) to carbon dioxide (CO2) and for utilization in bioplastic production by Ralstonia eutropha through the display of an enzyme complex on the cell surface. (United States)

    Hyeon, Jeong Eun; Kim, Seung Wook; Park, Chulhwan; Han, Sung Ok


    An enzyme complex for biological conversion of CO to CO2 was anchored on the cell surface of the CO2-utilizing Ralstonia eutropha and successfully resulted in a 3.3-fold increase in conversion efficiency. These results suggest that this complexed system may be a promising strategy for CO2 utilization as a biological tool for the production of bioplastics.

  1. An Efficient Preparation, Spectroscopic Properties, and Crystal Structure of 1,1-Bis(4-[2-(dimethylaminoethoxy]phenyl-2-(3-guaiazulenylethylene

    Directory of Open Access Journals (Sweden)

    Shin-ichi Takekuma


    Full Text Available Reaction of 2-(3-guaiazulenyl-1,1-bis(4-hydroxyphenylethylene with 2-chloroethyldimethylammonium chloride in acetone in the presence of K2CO3 at reflux temperature for 24 hours gives a new title compound in 89% yield. Spectroscopic properties and crystal structure of the target molecule are reported.

  2. Large-screen display industry: market and technology trends for direct view and projection displays (United States)

    Castellano, Joseph A.; Mentley, David E.


    Large screen information displays are defined as dynamic electronic displays that can be viewed by more than one person and are at least 2-feet wide. These large area displays for public viewing provide convenience, entertainment, security, and efficiency to the viewers. There are numerous uses for large screen information displays including those in advertising, transportation, traffic control, conference room presentations, computer aided design, banking, and military command/control. A noticeable characteristic of the large screen display market is the interchangeability of display types. For any given application, the user can usually choose from at least three alternative technologies, and sometimes from many more. Some display types have features that make them suitable for specific applications due to temperature, brightness, power consumption, or other such characteristic. The overall worldwide unit consumption of large screen information displays of all types and for all applications (excluding consumer TV) will increase from 401,109 units in 1995 to 655,797 units in 2002. On a unit consumption basis, applications in business and education represent the largest share of unit consumption over this time period; in 1995, this application represented 69.7% of the total. The market (value of shipments) will grow from DOL3.1 billion in 1995 to DOL3.9 billion in 2002. The market will be dominated by front LCD projectors and LCD overhead projector plates.

  3. Crystal science fundamentals


    Ramachandran, V.; Halfpenny, PJ; Roberts, KJ


    The fundamentals of crystal science notably crystallography, crystal chemistry, crystal defects, crystal morphology and the surface chemistry of crystals are introduced with particular emphasis on organic crystals.

  4. Naturally processed peptides spanning the HPA-1a polymorphism are efficiently generated and displayed from platelet glycoprotein by HLA-DRB3*0101-positive antigen-presenting cells. (United States)

    Anani Sarab, Gholamreza; Moss, Michael; Barker, Robert N; Urbaniak, Stanislaw J


    In neonatal alloimmune thrombocytopenia, almost all human platelet antigen (HPA)-1b1b mothers who produce anti-HPA-1a antibody through carrying an HPA-1a fetus are human histocompatibility leukocyte antigen (HLA)-DRB3*0101 positive. It is predicted that the HPA-1a Leu(33) polymorphism forms part of an HLA-DRB3*0101-restricted T-helper epitope, and acts as an anchor residue for binding this class II molecule. However, it is not known whether any corresponding peptides are naturally processed and presented from platelet glycoprotein. In this study, peptides displayed by a homozygous HLA-DRB3*0101 antigen-presenting cell line were identified after pulsing with recombinant HPA-1a (Leu(33) plexin-semaphorin-integrin domain). The peptides were eluted from HLA-DR molecules, fractionated by high performance liquid chromatography, and analyzed by tandem mass spectrometry. A "nested set" of naturally presented HPA-1a-derived peptides, each containing the Trp(25)-Leu(33) core epitope, was identified, with the most abundant member being the 16-mer Met(22)-Arg(37). These peptides may provide the basis for novel treatments to tolerize the corresponding T-helper response in women at risk of neonatal alloimmune thrombocytopenia.

  5. Synthesis of β-Ga{sub 2}O{sub 3} microstructures with efficient photocatalytic activity by annealing of GaSe single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Filippo, Emanuela, E-mail: [Department of Engineering for Innovation, University of Salento, Monteroni Street, Lecce I-73100 (Italy); Tepore, Marco [Department of Engineering for Innovation, University of Salento, Monteroni Street, Lecce I-73100 (Italy); Baldassarre, Francesca; Siciliano, Tiziana; Micocci, Goacchino [Department of Cultural Heritage, University of Salento, Lecce I-73100 (Italy); Quarta, Gianluca; Calcagnile, Lucio [Department of Engineering for Innovation, University of Salento, Monteroni Street, Lecce I-73100 (Italy); Tepore, Antonio [Department of Cultural Heritage, University of Salento, Lecce I-73100 (Italy)


    Graphical abstract: - Highlights: • Novel β-Ga{sub 2}O{sub 3} microstructures were achieved through annealing of GaSe single crystal. • Micro-flowers and leaves were characterized through XRD, SEM and Raman spectroscopy. • A possible growth mechanism was proposed. • Photocatalytic performance was evaluated. - Abstract: The synthesis of new β-Ga{sub 2}O{sub 3} microstructures was achieved through rapid annealing of GaSe single crystal at 850 °C in oxygen–ammonia co-flow for 30–120 min duration. The obtained micro-flowers and micro-leaves were carefully characterized through X-ray diffraction, scanning electron microscopy and Raman spectroscopy. SEM images demonstrated that the product consisted of flower-shaped microstructures, which as time elapsed evolved into leaves-like dendritic microstructures. These microstructures started off directly from oxidized single crystal. A possible growth mechanism was also proposed. Experimental results evidenced that synthesized microstructures exhibited good photocatalytic activity, better than commercial TiO{sub 2} powder (Degussa P25)

  6. 21 CFR 880.6970 - Liquid crystal vein locator. (United States)


    ...) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Miscellaneous... skin by displaying the color changes of heat sensitive liquid crystals (cholesteric esters)....

  7. Variations in performance of LCDs are still evident after DICOM gray-scale standard display calibration.

    LENUS (Irish Health Repository)

    Lowe, Joanna M


    Quality assurance in medical imaging is directly beneficial to image quality. Diagnostic images are frequently displayed on secondary-class displays that have minimal or no regular quality assurance programs, and treatment decisions are being made from these display types. The purpose of this study is to identify the impact of calibration on physical and psychophysical performance of liquid crystal displays (LCDs) and the extent of potential variance across various types of LCDs.

  8. LHCb Event display

    CERN Document Server

    Trisovic, Ana


    The LHCb Event Display was made for educational purposes at the European Organization for Nuclear Research, CERN in Geneva, Switzerland. The project was implemented as a stand-alone application using C++ and ROOT, a framework developed by CERN for data analysis. This paper outlines the development and architecture of the application in detail, as well as the motivation for the development and the goals of the exercise. The application focuses on the visualization of events recorded by the LHCb detector, where an event represents a set of charged particle tracks in one proton-proton collision. Every particle track is coloured by its type and can be selected to see its essential information such as mass and momentum. The application allows students to save this information and calculate the invariant mass for any pair of particles. Furthermore, the students can use additional calculating tools in the application and build up a histogram of these invariant masses. The goal for the students is to find a $D^0$ par...

  9. Colorimetry for CRT displays. (United States)

    Golz, Jürgen; MacLeod, Donald I A


    We analyze the sources of error in specifying color in CRT displays. These include errors inherent in the use of the color matching functions of the CIE 1931 standard observer when only colorimetric, not radiometric, calibrations are available. We provide transformation coefficients that prove to correct the deficiencies of this observer very well. We consider four different candidate sets of cone sensitivities. Some of these differ substantially; variation among candidate cone sensitivities exceeds the variation among phosphors. Finally, the effects of the recognized forms of observer variation on the visual responses (cone excitations or cone contrasts) generated by CRT stimuli are investigated and quantitatively specified. Cone pigment polymorphism gives rise to variation of a few per cent in relative excitation by the different phosphors--a variation larger than the errors ensuing from the adoption of the CIE standard observer, though smaller than the differences between some candidate cone sensitivities. Macular pigmentation has a larger influence, affecting mainly responses to the blue phosphor. The estimated combined effect of all sources of observer variation is comparable in magnitude with the largest differences between competing cone sensitivity estimates but is not enough to disrupt very seriously the relation between the L and M cone weights and the isoluminance settings of individual observers. It is also comparable with typical instrumental colorimetric errors, but we discuss these only briefly.

  10. Data Display in Qualitative Research

    Directory of Open Access Journals (Sweden)

    Susana Verdinelli PsyD


    Full Text Available Visual displays help in the presentation of inferences and conclusions and represent ways of organizing, summarizing, simplifying, or transforming data. Data displays such as matrices and networks are often utilized to enhance data analysis and are more commonly seen in quantitative than in qualitative studies. This study reviewed the data displays used by three prestigious qualitative research journals within a period of three years. The findings include the types of displays used in these qualitative journals, the frequency of use, and the purposes for using visual displays as opposed to presenting data in text.

  11. Progress on photonic crystals

    CERN Document Server

    Lecoq, P; Gundacker, S; Hillemanns, H; Jarron, P; Knapitsch, A; Leclercq, J L; Letartre, X; Meyer, T; Pauwels, K; Powolny, F; Seassal, C


    The renewal of interest for Time of Flight Positron Emission Tomography (TOF PET) has highlighted the need for increasing the light output of scintillating crystals and in particular for improving the light extraction from materials with a high index of refraction. One possible solution to overcome the problem of total internal reflection and light losses resulting from multiple bouncing within the crystal is to improve the light extraction efficiency at the crystal/photodetector interface by means of photonic crystals, i.e. media with a periodic modulation of the dielectric constant at the wavelength scale. After a short reminder of the underlying principles this contribution proposes to present the very encouraging results we have recently obtained on LYSO pixels and the perspectives on other crystals such as BGO, LuYAP and LuAG. These results confirm the impressive predictions from our previously published Monte Carlo simulations. A detailed description of the sample preparation procedure is given as well ...

  12. Modeling Power-Constrained Optimal Backlight Dimming for Color Displays

    DEFF Research Database (Denmark)

    Burini, Nino; Nadernejad, Ehsan; Korhonen, Jari


    In this paper, we present a framework for modeling color liquid crystal displays (LCDs) having local light-emitting diode (LED) backlight with dimming capability. The proposed framework includes critical aspects like leakage, clipping, light diffusion and human perception of luminance and allows...

  13. Spatial constraints of stereopsis in video displays (United States)

    Schor, Clifton


    Recent development in video technology, such as the liquid crystal displays and shutters, have made it feasible to incorporate stereoscopic depth into the 3-D representations on 2-D displays. However, depth has already been vividly portrayed in video displays without stereopsis using the classical artists' depth cues described by Helmholtz (1866) and the dynamic depth cues described in detail by Ittleson (1952). Successful static depth cues include overlap, size, linear perspective, texture gradients, and shading. Effective dynamic cues include looming (Regan and Beverly, 1979) and motion parallax (Rogers and Graham, 1982). Stereoscopic depth is superior to the monocular distance cues under certain circumstances. It is most useful at portraying depth intervals as small as 5 to 10 arc secs. For this reason it is extremely useful in user-video interactions such as telepresence. Objects can be manipulated in 3-D space, for example, while a person who controls the operations views a virtual image of the manipulated object on a remote 2-D video display. Stereopsis also provides structure and form information in camouflaged surfaces such as tree foliage. Motion parallax also reveals form; however, without other monocular cues such as overlap, motion parallax can yield an ambiguous perception. For example, a turning sphere, portrayed as solid by parallax can appear to rotate either leftward or rightward. However, only one direction of rotation is perceived when stereo-depth is included. If the scene is static, then stereopsis is the principal cue for revealing the camouflaged surface structure. Finally, dynamic stereopsis provides information about the direction of motion in depth (Regan and Beverly, 1979). Clearly there are many spatial constraints, including spatial frequency content, retinal eccentricity, exposure duration, target spacing, and disparity gradient, which - when properly adjusted - can greatly enhance stereodepth in video displays.

  14. Dynamic exit pupil trackers for autostereoscopic displays. (United States)

    Akşit, Kaan; Baghsiahi, Hadi; Surman, Phil; Ölçer, Selim; Willman, Eero; Selviah, David R; Day, Sally; Urey, Hakan


    This paper describes the first demonstrations of two dynamic exit pupil (DEP) tracker techniques for autostereoscopic displays. The first DEP tracker forms an exit pupil pair for a single viewer in a defined space with low intraocular crosstalk using a pair of moving shutter glasses located within the optical system. A display prototype using the first DEP tracker is constructed from a pair of laser projectors, pupil-forming optics, moving shutter glasses at an intermediate pupil plane, an image relay lens, and a Gabor superlens based viewing screen. The left and right eye images are presented time-sequentially to a single viewer and seen as a 3D image without wearing glasses and allows the viewer to move within a region of 40 cm × 20 cm in the lateral plane, and 30 cm along the axial axis. The second DEP optics can move the exit pupil location dynamically in a much larger 3D space by using a custom spatial light modulator (SLM) forming an array of shutters. Simultaneous control of multiple exit pupils in both lateral and axial axes is demonstrated for the first time and provides a viewing volume with an axial extent of 0.6-3 m from the screen and within a lateral viewing angle of ± 20° for multiple viewers. This system has acceptable crosstalk (< 5%) between the stereo image pairs. In this novel version of the display the optical system is used as an advanced dynamic backlight for a liquid crystal display (LCD). This has advantages in terms of overall display size as there is no requirement for an intermediate image, and in image quality. This system has acceptable crosstalk (< 5%) between the stereo image pairs.

  15. Unique interactive projection display screen

    Energy Technology Data Exchange (ETDEWEB)

    Veligdan, J.T.


    Projection systems continue to be the best method to produce large (1 meter and larger) displays. However, in order to produce a large display, considerable volume is typically required. The Polyplanar Optic Display (POD) is a novel type of projection display screen, which for the first time, makes it possible to produce a large projection system that is self-contained and only inches thick. In addition, this display screen is matte black in appearance allowing it to be used in high ambient light conditions. This screen is also interactive and can be remotely controlled via an infrared optical pointer resulting in mouse-like control of the display. Furthermore, this display need not be flat since it can be made curved to wrap around a viewer as well as being flexible.

  16. MicroDisplay technology: from eyeglass-mounted displays to portable projectors to the Dick Tracy video phone (United States)

    Alvelda, Phillip


    MicroDisplay devices are based on a combination of technologies ranging from the extreme integration capability of conventionally fabricated CMOS active-matrix liquid crystal display substrates to proprietary tunable color- filter technology, to optical distortion correction technology for lens-system compensation. All of these technologies were devised to create a line of application- specific integrated circuit single-chip display devices with integrated computing, memory, and communication circuitry. Next-generation portable communication, computer, and consumer electronic devices such as truly portable monitor and TV projectors, eyeglass-clip-on virtual displays, pagers and personal communication services hand-sets, and wristwatch-mounted video phones are all target markets for MicroDisplay technology.

  17. LBO晶体长度对全固态473nm蓝光激光器效率的影响%LBO Crystal Length on the Efficiency of All Solid-State 473 nm Blue Laser

    Institute of Scientific and Technical Information of China (English)

    李业秋; 刘艳娟; 李勇; 岱钦


    报道了结构紧凑、输出稳定的473 nm连续全固态蓝光激光器.模拟分析了LBO晶体长度与激光输出效率的关系,选择了最佳长度为10 mm的Ⅰ类相位匹配的LBO晶体.当抽运功率为3W时,获得了210 mW的473 nm蓝光激光输出功率,光-光转换效率为7%,激光输出功率起伏小于3%.%A compact and stable 473 nm continuous all-solid-state blue laser is reported. Simulation analysis of the relationship between the LBO crystal length and the laser output efficiency is done. An optimal length of 10 mm type I phase-matching LBO crystal is chosen. Under the pump power of 3 W, 210 mW of the blue laser at 473 nm is obtained. The optical-to-optical conversion efficiency is up to 7% . The fluctuation of laser output power is less than 3%.

  18. Rapid display of radiographic images (United States)

    Cox, Jerome R., Jr.; Moore, Stephen M.; Whitman, Robert A.; Blaine, G. James; Jost, R. Gilbert; Karlsson, L. M.; Monsees, Thomas L.; Hassen, Gregory L.; David, Timothy C.


    The requirements for the rapid display of radiographic images exceed the capabilities of widely available display, computer, and communications technologies. Computed radiography captures data with a resolution of about four megapixels. Large-format displays are available that can present over four megapixels. One megapixel displays are practical for use in combination with large-format displays and in areas where the viewing task does not require primary diagnosis. This paper describes an electronic radiology system that approximates the highest quality systems, but through the use of several interesting techniques allows the possibility of its widespread installation throughout hospitals. The techniques used can be grouped under three major system concepts: a local, high-speed image server, one or more physician's workstations each with one or more high-performance auxiliary displays specialized to the radiology viewing task, and dedicated, high-speed communication links between the server and the displays. This approach is enhanced by the use of a progressive transmission scheme to decrease the latency for viewing four megapixel images. The system includes an image server with storage for over 600 4-megapixel images and a high-speed link. A subsampled megapixel image is fetched from disk and transmitted to the display in about one second followed by the full resolution 4-megapixel image in about 2.5 seconds. Other system components include a megapixel display with a 6-megapixel display memory space and frame-rate update of image roam, zoom, and contrast. Plans for clinical use are presented.

  19. Military display market segment: helicopters (United States)

    Desjardins, Daniel D.; Hopper, Darrel G.


    The military display market is analyzed in terms of one of its segments: helicopter displays. Parameters requiring special consideration, to include luminance ranges, contrast ratio, viewing angles, and chromaticity coordinates, are examined. Performance requirements for rotary-wing displays relative to several premier applications are summarized. Display sizes having aggregate defense applications of 5,000 units or greater and having DoD applications across 10 or more platforms, are tabulated. The issue of size commonality is addressed where distribution of active area sizes across helicopter platforms, individually, in groups of two through nine, and ten or greater, is illustrated. Rotary-wing displays are also analyzed by technology, where total quantities of such displays are broken out into CRT, LCD, AMLCD, EM, LED, Incandescent, Plasma and TFEL percentages. Custom, versus Rugged commercial, versus commercial off-the-shelf designs are contrasted. High and low information content designs are identified. Displays for several high-profile military helicopter programs are discussed, to include both technical specifications and program history. The military display market study is summarized with breakouts for the helicopter market segment. Our defense-wide study as of March 2004 has documented 1,015,494 direct view and virtual image displays distributed across 1,181 display sizes and 503 weapon systems. Helicopter displays account for 67,472 displays (just 6.6% of DoD total) and comprise 83 sizes (7.0% of total DoD) in 76 platforms (15.1% of total DoD). Some 47.6% of these rotary-wing applications involve low information content displays comprising just a few characters in one color; however, as per fixed-wing aircraft, the predominant instantiation involves higher information content units capable of showing changeable graphics, color and video.

  20. X-1 on display (United States)


    A Bell Aircraft Corporation X-1 series aircraft on display at an Open House at NACA Muroc Flight Test Unit or High-Speed Flight Research Station hangar on South Base of Edwards Air Force Base, California. (The precise date of the photo is uncertain, but it is probably before 1948.) The instrumentation that was carried aboard the aircraft to gather data is on display. The aircraft data was recorded on oscillograph film that was read, calibrated, and converted into meaningful parameters for the engineers to evaluate from each research flight. In the background of the photo are several early U.S. jets. These include several Lockheed P-80 Shooting Stars, which were used as chase planes on X-1 flights; two Bell P-59 Airacomets, the first U.S. jet pursuit aircraft (fighter in later parlance); and a prototype Republic XP-84 Thunderjet. There were five versions of the Bell X-1 rocket-powered research aircraft that flew at the NACA High-Speed Flight Research Station, Edwards, California. The bullet-shaped X-1 aircraft were built by Bell Aircraft Corporation, Buffalo, N.Y. for the U.S. Army Air Forces (after 1947, U.S. Air Force) and the National Advisory Committee for Aeronautics (NACA). The X-1 Program was originally designated the XS-1 for eXperimental Sonic. The X-1's mission was to investigate the transonic speed range (speeds from just below to just above the speed of sound) and, if possible, to break the 'sound barrier.' Three different X-1s were built and designated: X-1-1, X-1-2 (later modified to become the X-1E), and X-1-3. The basic X-1 aircraft were flown by a large number of different pilots from 1946 to 1951. The X-1 Program not only proved that humans could go beyond the speed of sound, it reinforced the understanding that technological barriers could be overcome. The X-1s pioneered many structural and aerodynamic advances including extremely thin, yet extremely strong wing sections; supersonic fuselage configurations; control system requirements; powerplant