WorldWideScience

Sample records for optical standards

  1. Fiber optics standard dictionary

    CERN Document Server

    Weik, Martin H

    1997-01-01

    Fiber Optics Vocabulary Development In 1979, the National Communications System published Technical InfonnationBulle­ tin TB 79-1, Vocabulary for Fiber Optics and Lightwave Communications, written by this author. Based on a draft prepared by this author, the National Communications System published Federal Standard FED-STD-1037, Glossary of Telecommunications Terms, in 1980 with no fiber optics tenns. In 1981, the first edition of this dictionary was published under the title Fiber Optics and Lightwave Communications Standard Dictionary. In 1982, the then National Bureau of Standards, now the National Institute of Standards and Technology, published NBS Handbook 140, Optical Waveguide Communications Glossary, which was also published by the General Services Admin­ istration as PB82-166257 under the same title. Also in 1982, Dynamic Systems, Inc. , Fiberoptic Sensor Technology Handbook, co-authored and edited by published the this author, with an extensive Fiberoptic Sensors Glossary. In 1989, the handbook w...

  2. Standardization in optical coating characterisation

    Institute of Scientific and Technical Information of China (English)

    D.Ristau

    2005-01-01

    In the rapid development course of laser technology and modern optics, optical metrology continuously gains importance for the quality management in the industrial production environment and also for research in optical coatings. Besides absorption and scatter losses, the spectral characteristics and laser induced damage thresholds are considered as common quality factors for coated optical components and often define the optimization targets for new products and applications. Also, these quality parameters are the basis for the comparison of commercial optics and can be found in the product catalogues of most manufacturers of optical components. As a consequence, standardization of characterisation procedures for these fundamental properties evolved to a crucial point for the optics industry. During the last decade, adapted standard measurement techniques have been elaborated and discussed by representatives from many industrial companies and research institutes within working groups of the International Organisation for Standardization (ISO). In this contribution, the current state of standardized characterisation techniques for optical coatings is summarised. Selected standards for the measurement of absorption (ISO 11551), scattering (ISO 13696) and laser induced damage thresholds (ISO 11254, Parts 1 and 2) will be described and discussed in view of their applicability and reproducibility. The report will be concluded by an outlook on the current projects and future tasks of standardization in optics characterisation.

  3. Active Faraday optical frequency standard.

    Science.gov (United States)

    Zhuang, Wei; Chen, Jingbiao

    2014-11-01

    We propose the mechanism of an active Faraday optical clock, and experimentally demonstrate an active Faraday optical frequency standard based on narrow bandwidth Faraday atomic filter by the method of velocity-selective optical pumping of cesium vapor. The center frequency of the active Faraday optical frequency standard is determined by the cesium 6 (2)S(1/2) F=4 to 6 (2)P(3/2) F'=4 and 5 crossover transition line. The optical heterodyne beat between two similar independent setups shows that the frequency linewidth reaches 281(23) Hz, which is 1.9×10(4) times smaller than the natural linewidth of the cesium 852-nm transition line. The maximum emitted light power reaches 75 μW. The active Faraday optical frequency standard reported here has advantages of narrow linewidth and reduced cavity pulling, which can readily be extended to other atomic transition lines of alkali and alkaline-earth metal atoms trapped in optical lattices at magic wavelengths, making it useful for new generation of optical atomic clocks.

  4. Different ways to active optical frequency standards

    Science.gov (United States)

    Pan, Duo; Xue, Xiaobo; Zhang, Xiaogang; Chen, Jingbiao

    2016-06-01

    Active optical frequency standard, or active optical clock, is a new concept of optical frequency standard, where a weak feedback with phase coherence information in optical bad-cavity limitation is formed, and the continuous self-sustained coherent stimulated emission between two atomic transition levels with population inversion is realized. Through ten years of both theoretical and experimental exploration, the narrow linewidth and suppression of cavity pulling effect of active optical frequency standard have been initially proved. In this paper, after a simple review, we will mainly present the most recent experimental progresses of active optical frequency standards in Peking University, including 4-level cesium active optical frequency standards and active Faraday optical frequency standards. The future development of active optical frequency standards is also discussed.

  5. International Standardization Activities for Optical Amplifiers

    Institute of Scientific and Technical Information of China (English)

    Haruo Okamura

    2003-01-01

    International standardization activities for Optical Amplifiers at IECTC86 and ITU-T SG15 are reviewed. Current discussions include Optical Amplifier safety guideline, Reliability standard, Rest methods of Noise and PMD, Definitions of Raman amplifier parameters and OA classification.

  6. Hermetic optical-fiber iodine frequency standard.

    Science.gov (United States)

    Light, Philip S; Anstie, James D; Benabid, Fetah; Luiten, Andre N

    2015-06-15

    We have built an optical-frequency standard based on interrogating iodine vapor that has been trapped within the hollow core of a hermetically sealed kagome-lattice photonic crystal fiber. A frequency-doubled Nd:YAG laser locked to a hyperfine component of the P(142)37-0 I2127 transition using modulation transfer spectroscopy shows a frequency stability of 3×10(-11) at 100 s. We discuss the impediments in integrating this all-fiber standard into a fully optical-fiber-based system, and suggest approaches that could improve performance of the frequency standard substantially.

  7. Optical glass: standards - present state and outlook

    Science.gov (United States)

    Hartmann, Peter

    2015-10-01

    In 1996, the international organization for standardization ISO started the standards series ISO 10110 specifying indications in drawings of optical elements. Three parts cover material properties: part 2 (stress birefringence), 3 (bubbles and inclusions), and 4 (inhomogeneity and striae). Customers used to just send optical element drawings to glass manufacturers often leading to uncertainty, overspecification, and delivery problems. The raw glass standard ISO 12123 of 2010 allows direct addressing of raw glass specifications. Harmonizing ISO 10110 with ISO 12123 and progress in inspection methods require updating of the material specifying parts. A new part 18 containing all properties is under preparation and is meant to replace parts 2-4. ISO 12123 will be amended by introducing definitions for relative partial dispersions and reference normal lines and grade denominations for tolerance ranges. The working draft ISO/WD 10110 part 18 extends indication possibilities to allow relating to ISO 12123 while ensuring backward compatibility. Default optical glass quality and direct specification of raw glass simplify tolerancing considerably. Annexes support selection of appropriate quality classes referring to optical element size categories. Test and inspection standards on chemical resistances, hardness, stress birefringence, and optical homogeneity will be maintained. Standards for water resistance, refractive index, and striae inspection are being prepared.

  8. Optical frequency standards for time and length applications

    Science.gov (United States)

    Hong, Feng-Lei

    2017-01-01

    The last decade has witnessed tremendous progress in research on optical frequency metrology. Optical frequency standards using optical lattice and single-ion trap technologies have reached levels of stability and accuracy that surpass the performance of the best Cs fountain atomic clocks by orders of magnitude. Optical frequency standards are also used for various applications including length metrology. Optical frequency measurement and links using optical frequency combs and optical fibres play important roles in the development of optical frequency standards. This article introduces optical frequency standards recommended by the International Committee for Weights and Measures (CIPM) along with updates provided by recent research results. Frequency ratio measurements and remote frequency comparisons are addressed in relation to the work whose goal is to redefine the second. Optical frequency standard and optical frequency comb applications are also described.

  9. Full-mesh optical backplane with standard MM fiber ribbons

    Science.gov (United States)

    Ferrario, M.; Coviello, D.; Boffi, P.; Martinelli, M.; Basile, V.; Fassi, I.; Falcucci, M.; Renghini, C.; Scalmati, Paolo

    2016-03-01

    A new optical backplane solution is proposed for high-capacity ICT apparatus. A modular, scalable and full-mesh bandwidth-upgradable optical interconnection between optoelectronic boards is guaranteed thanks to an optimized layout of standard MM 12-fiber ribbons which divides the overall backplane into several independent optical sub-circuits. The novel automated assembly procedure of fiber ribbons inside sub-circuits with a robotic work-cell is described. System validation of the optical backplane performed with commercially available MM 12-fiber transceivers @10Gb/s proved the feasibility of the proposed solution for future optical interconnections with terabit overall capacity.

  10. The Optically Pumped Cs Frequency Standard at the NRLM

    Science.gov (United States)

    1987-12-01

    References 1. J.L. Picqu6, "Hyperfine optical pumping of a cesium atomic beam, and applications," Metrologia, vo1.13, pp.115-119, 1977. 2. M. Arditi and... Arditi , "A caesium beam atomic clock with laser optical pumping, as a potential frequency standard," Metrologia, vo1.18, pp.59-66, 1982. 4. G

  11. QKD in Standard Optical Telecommunications Networks

    CERN Document Server

    Lancho, D; Elkouss, D; Soto, M; Martin, V; 10.1007/978-3-642-11731-2_18

    2010-01-01

    To perform Quantum Key Distribution, the mastering of the extremely weak signals carried by the quantum channel is required. Transporting these signals without disturbance is customarily done by isolating the quantum channel from any noise sources using a dedicated physical channel. However, to really profit from this technology, a full integration with conventional network technologies would be highly desirable. Trying to use single photon signals with others that carry an average power many orders of magnitude bigger while sharing as much infrastructure with a conventional network as possible brings obvious problems. The purpose of the present paper is to report our efforts in researching the limits of the integration of QKD in modern optical networks scenarios. We have built a full metropolitan area network testbed comprising a backbone and an access network. The emphasis is put in using as much as possible the same industrial grade technology that is actually used in already installed networks, in order t...

  12. Optical networking standards a comprehensive guide for professionals

    CERN Document Server

    2006-01-01

    Optical Networking Standards: A Comprehensive Guide for Professionals provides a single source reference of over a hundred standards and industry technical specifications for optical networks at all levels: from components to networking systems through global networks, as well as coverage of networks management and services. This book focuses on the recently approved, adopted and implemented standards that have fueled the development of versatile switches, routers and multi-service provisioning platforms. These networking elements have enabled the service-providers world-wide to offer flexible yet customized bundled-services based on IP, MPLS and Carrier-Grade Ethernet.

  13. Commercialization and Standardization Progress Towards an Optical Communications Earth Relay

    Science.gov (United States)

    Edwards, Bernard L.; Israel, David J.

    2015-01-01

    NASA is planning to launch the next generation of a space based Earth relay in 2025 to join the current Space Network, consisting of Tracking and Data Relay Satellites in space and the corresponding infrastructure on Earth. While the requirements and architecture for that relay satellite are unknown at this time, NASA is investing in communications technologies that could be deployed to provide new communications services. One of those new technologies is optical communications. The Laser Communications Relay Demonstration (LCRD) project, scheduled for launch in 2018 as a hosted payload on a commercial communications satellite, is a critical pathfinder towards NASA providing optical communications services on the next generation space based relay. This paper will describe NASA efforts in the on-going commercialization of optical communications and the development of inter-operability standards. Both are seen as critical to making optical communications a reality on future NASA science and exploration missions. Commercialization is important because NASA would like to eventually be able to simply purchase an entire optical communications terminal from a commercial provider. Inter-operability standards are needed to ensure that optical communications terminals developed by one vendor are compatible with the terminals of another. International standards in optical communications would also allow the space missions of one nation to use the infrastructure of another.

  14. International standards for optical circuit board fabrication, assembly and measurement

    Science.gov (United States)

    Pitwon, Richard; Immonen, Marika; Wang, Kai; Itoh, Hideo; Shioda, Tsuyoshi; Wu, Jinhua; Zhu, Long Xiu; Yan, Hui Juan; Worrall, Alex

    2016-03-01

    The commercial adoption of electro-optical printed circuit board (EOCB) technology will be accelerated by the development of industrial and conformity standards for high volume fabrication, connector assembly and waveguide measurement. In this paper, we introduce international standardisation activities surrounding EOCBs and report on industrial processes developed for the high volume fabrication of complex EOCBs with embedded multimode polymer waveguides including a first connector standard for polymer waveguide termination. We focus on solving a serious historic problem with the measurement of optical waveguide systems, namely the lack of harmonised measurement conditions for optical waveguides, which to this day gives rise to strong inconsistencies in the results of measurements by different parties on the same waveguide. We report on the development of a standard to ensure repeatable measurement of optical waveguides, whereby we demonstrate how the application of a measurement identification system and proposed reference measurement conditions can bring variation in measurement results to within 5%, thereby serving as the basis for a formal reliable optical waveguide measurement methodology.

  15. Quantum metrology. Optically measuring force near the standard quantum limit.

    Science.gov (United States)

    Schreppler, Sydney; Spethmann, Nicolas; Brahms, Nathan; Botter, Thierry; Barrios, Maryrose; Stamper-Kurn, Dan M

    2014-06-27

    The Heisenberg uncertainty principle sets a lower bound on the noise in a force measurement based on continuously detecting a mechanical oscillator's position. This bound, the standard quantum limit, can be reached when the oscillator subjected to the force is unperturbed by its environment and when measurement imprecision from photon shot noise is balanced against disturbance from measurement back-action. We applied an external force to the center-of-mass motion of an ultracold atom cloud in a high-finesse optical cavity and measured the resulting motion optically. When the driving force is resonant with the cloud's oscillation frequency, we achieve a sensitivity that is a factor of 4 above the standard quantum limit and consistent with theoretical predictions given the atoms' residual thermal disturbance and the photodetection quantum efficiency.

  16. Optically Measuring Force near the Standard Quantum Limit

    CERN Document Server

    Schreppler, Sydney; Brahms, Nathan; Botter, Thierry; Barrios, Maryrose; Stamper-Kurn, Dan M

    2013-01-01

    The Heisenberg uncertainty principle sets a lower bound on the sensitivity of continuous optical measurements of force. This bound, the standard quantum limit, can only be reached when a mechanical oscillator subjected to the force is unperturbed by its environment, and when measurement imprecision from photon shot-noise is balanced against disturbance from measurement backaction. We apply an external force to the center-of-mass motion of an ultracold atom cloud in a high-finesse optical cavity. The optomechanically transduced response clearly demonstrates the trade-off between measurement imprecision and back-action noise. We achieve a sensitivity that is consistent with theoretical predictions for the quantum limit given the atoms' slight residual thermal disturbance and the photodetection quantum efficiency, and is a factor of 4 above the absolute standard quantum limit.

  17. High Performance Small Optically Pumped Caesium Beam Frequency Standard

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-Wei; YANG Dong-Hai

    2007-01-01

    An experiment of a high performance small optically pumped caesium (Cs) beam frequency standard is reported. An extended cavity diode laser works as the probing laser, of which the frequency is stabilized by the Zeeman modulation method. The running parameters of the frequency standard are dynamically optimized via digital servo electronics. The experimental setup improves the frequency stability up to 1.8 × 10-12 atτ= 1 s and about 1.0 × 10~13 at τ= 105 s (Allan deviation).

  18. Stress Optical Coefficient, Test Methodology, and Glass Standard Evaluation

    Science.gov (United States)

    2016-05-01

    it can be used as an additional glass characterization method . If the SOC of a glass sample is known, the stress state of a glass specimen can be...evaluated through photoelastic methods both qualitatively and quantitatively. Approved for public release; distribution is unlimited. 11 8...ARL-TN-0756 ● MAY 2016 US Army Research Laboratory Stress Optical Coefficient, Test Methodology, and Glass Standard Evaluation

  19. Femtosecond fibre laser stabilisation to an optical frequency standard using a KTP electro-optic crystal

    Energy Technology Data Exchange (ETDEWEB)

    Nyushkov, B N [Novosibirsk State University, Novosibirsk (Russian Federation); Pivtsov, V S; Koliada, N A [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Kaplun, A B; Meshalkin, A B [S.S. Kutateladze Institute of Heat Physics, Siberian Division of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2015-05-31

    A miniature intracavity KTP-based electro-optic phase modulator has been developed which can be used for effective stabilisation of an optical frequency comb of a femtosecond erbiumdoped fibre laser to an optical frequency standard. The use of such an electro-optic modulator (EOM) has made it possible to extend the working frequency band of a phase-locked loop system for laser stabilisation to several hundred kilohertz. We demonstrate that the KTP-based EOM is sufficiently sensitive even at a small optical length, which allows it to be readily integrated into cavities of femtosecond fibre lasers with high mode frequency spacings (over 100 MHz). (extreme light fields and their applications)

  20. Comparing a mercury optical lattice clock with microwave and optical frequency standards

    CERN Document Server

    Tyumenev, R; Bilicki, S; Bookjans, E; Targat, R Le; Lodewyck, J; Nicolodi, D; Coq, Y Le; Abgrall, M; Guéna, J; De Sarlo, L; Bize, S

    2016-01-01

    In this paper we report the evaluation of an optical lattice clock based on neutral mercury down to a relative uncertainty of $1.7\\times 10^{-16}$. Comparing this characterized frequency standard to a Cs atomic fountain we determine the absolute frequency of the $^1S_0 \\rightarrow \\phantom{}^3P_0$ transition of $^{199}$Hg as $\

  1. Systematic Shifts for Ytterbium-ion Optical Frequency Standards

    CERN Document Server

    Batra, N; Gupta, A Sen; Singh, Sukhjit; Arora, Amisha; Arora, Bindiya

    2014-01-01

    The projected systematic uncertainties of single trapped Ytterbium-ion optical frequency standards are estimated for the quadrupole and octupole transitions which are at wavelengths 435.5 nm and 467 nm, respectively. Finite temperature of the ion and its interaction with the external fields introduce drift in the measured frequency compared to its absolute value. Frequency shifts due to electric quadrupole moment, induced polarization and excess micromotion of the ion depend on electric fields, which are estimated in this article. Geometry of the trap electrodes also result in unwanted electric fields which have been considered in our calculation. Magnetic field induced shift and Stark shifts due to electro-magnetic radiation at a surrounding temperature are also estimated. At CSIR-NPL, we are developing a frequency standard based on the octupole transition for which the systematic uncertainties are an order of magnitude smaller than that using the quadrupole transition, as described here.

  2. An optically trapped mirror for reaching the standard quantum limit

    CERN Document Server

    Matsumoto, Nobuyuki; Aso, Yoichi; Tsubono, Kimio

    2014-01-01

    The preparation of a mechanical oscillator driven by quantum back-action is a fundamental requirement to reach the standard quantum limit (SQL) for force measurement, in optomechanical systems. However, thermal fluctuating force generally dominates a disturbance on the oscillator. In the macroscopic scale, an optical linear cavity including a suspended mirror has been used for the weak force measurement, such as gravitational-wave detectors. This configuration has the advantages of reducing the dissipation of the pendulum (i.e., suspension thermal noise) due to a gravitational dilution by using a thin wire, and of increasing the circulating laser power. However, the use of the thin wire is weak for an optical torsional anti-spring effect in the cavity, due to the low mechanical restoring force of the wire. Thus, there is the trade-off between the stability of the system and the sensitivity. Here, we describe using a triangular optical cavity to overcome this limitation for reaching the SQL. The triangular cav...

  3. Nantenna for Standard 1550 nm Optical Communication Systems

    Directory of Open Access Journals (Sweden)

    Waleed Tariq Sethi

    2016-01-01

    Full Text Available Nanoscale transmission and reception technologies will play a vital role and be part of the next generation communication networks. This applies for all application fields including imaging, health, biosensing, civilian, and military communications. The detection of light frequency using nanooptical antennas may possibly become a good competitor to the semiconductor based photodetector because of the simplicity of integration, cost, and inherent capability to detect the phase and amplitude instead of power only. In this paper, authors propose simulated design of a hexagonal dielectric loaded nantenna (HDLN and explore its potential benefits at the standard optical C-band (1550 nm. The proposed nantenna consists of “Ag-SiO2-Ag” structure, consisting of “Si” hexagonal dielectric with equal lengths fed by “Ag” nanostrip transmission line. The simulated nantenna achieves an impedance bandwidth of 3.7% (190.9 THz–198.1 THz and a directivity of 8.6 dBi, at a center frequency of 193.5 THz, covering most of the ITU-T standard optical transmission window (C-band. The hexagonal dielectric nantenna produces HE20δ modes and the wave propagation is found to be end-fire. The efficiency of the nantenna is proven via numerical expressions, thus making the proposed design viable for nanonetwork communications.

  4. Comparing a mercury optical lattice clock with microwave and optical frequency standards

    Science.gov (United States)

    Tyumenev, R.; Favier, M.; Bilicki, S.; Bookjans, E.; Le Targat, R.; Lodewyck, J.; Nicolodi, D.; Le Coq, Y.; Abgrall, M.; Guéna, J.; De Sarlo, L.; Bize, S.

    2016-11-01

    In this paper we report the evaluation of an optical lattice clock based on neutral mercury with a relative uncertainty of 1.7× {10}-16. Comparing this characterized frequency standard to a 133Cs atomic fountain we determine the absolute frequency of the {}1{{{S}}}0\\to {}3{{{P}}}0 transition of 199Hg as {ν }{Hg}=1128 575 290 808 154.62 {Hz}+/- 0.19 {Hz}({statistical})+/- 0.38 {Hz} (systematic), limited solely by the realization of the SI second. Furthermore, by comparing the mercury optical lattice clock to a 87Rb atomic fountain, we determine for the first time to our knowledge the ratio between the 199Hg clock transition and the 87Rb ground state hyperfine transition. Finally we present a direct optical to optical measurement of the 199Hg/87Sr frequency ratio. The obtained value of {ν }{Hg}/{ν }{Sr} = 2.629 314 209 898 909 15 with a fractional uncertainty of 1.8× {10}-16 is in excellent agreement with a similar measurement obtained by Yamanaka et al (2015 Phys. Rev. Lett. 114 230801). This makes this frequency ratio one of the few physical quantities agreed upon by different laboratories to this level of uncertainty. Frequency ratio measurements of the kind reported in this paper have a strong impact for frequency metrology and fundamental physics as they can be used to monitor putative variations of fundamental constants.

  5. Silica optical fiber technology for devices and components design, fabrication, and international standards

    CERN Document Server

    Oh, Kyunghwan

    2012-01-01

    From basic physics to new products, Silica Optical Fiber Technology for Device and Components examines all aspects of specialty optical fibers. Moreover, the inclusion of the latest international standards governing optical fibers enables you to move from research to fabrication to commercialization. Reviews all the latest specialty optical fiber technologies, including those developed for high capacity WDM applications; broadband fiber amplifiers; fiber filleters based on periodic coupling; fiber branching devices; and fiber terminations Discusses key differences among sing

  6. Theoretical analysis and system design of two-photon based optical frequency standards

    Science.gov (United States)

    Burger, J. P.; Jivan, P.; Matthee, C.; Kritzinger, R.; Hussein, H.; Terra, O.

    2014-06-01

    The National Metrology Institute of South Africa (NMISA) is developing a new optical frequency standard based on the Rubidium two-photon transition in collaboration with the National Institute of Standards (NIS, Egypt) that will use both bulk and fiber optics in the system. This is system is called A-POD; an acronym for a portable photonic oscillator device. Rubidium two-photon standards can yield relatively simple and precise standards that are compatible with standard Ti:Sapphire optical frequency combs, as well as the need for a precise frequency standard in the optical telecommunication domain and for measurement of length with a visible beam. The robustness and transportability of the standard are important considerations for the optical frequency standard. This projects implements a framework for better two-photon standards that can be highly accurate, and possibly compete with much more complex clocks in the metrology environment, and especially so in the smaller national metrology institutes found in the developing world. This paper discusses the design constraints and the development considerations towards the optical setup. The robustness and transportability was greatly improved via the usage of optical fiber in the light source of the system, or even in atom-light interaction region. Of particular importance are the beam parameters inside the atomic interaction area. The extent of Doppler broadening and the intensity dependent line shift have to be optimized within practical extents, where both these aspects are affected by the beam shape and optical geometry. A way to fully treat the optical beam effects together with atomic movement is proposed. Furthermore a method is proposed to do real time compensation of intensity dependent light shift, which could have major applicability to frequency standards in general - the complexity is shifted from physical setups to digital signal processing, which is easily adaptable and stable.

  7. An approach to the optical interconnect made in standard CMOS process

    Institute of Scientific and Technical Information of China (English)

    Yu Changliang; Mao Luhong; Xiao Xindong; Xie Sheng; Zhang Shilin

    2009-01-01

    A standard CMOS optical interconnect is proposed, including an octagonal-annular emitter, a field oxide,metal 1-PSG/BPSG-metal 2 dual waveguide, and an ultra high-sensitivity optical receiver integrated with a fingered P/N-well/P-sub dual photodiode detector. The optical interconnect is implemented in a Chartered 3.3-V 0.35-μm standard analog CMOS process with two schemes for the research of the substrate noise coupling effect on the optical interconnect performance: with or without a GND-guardring around the emitter. The experiment results show that the optical interconnect can work at 100 kHz, and it is feasible to implement optical interconnects in standard CMOS processes.

  8. Review And Update Of Fiber Optic Interconnect Standardization

    Science.gov (United States)

    Makuch, John A.

    1980-09-01

    An unofficial discussion of the status of interconnect standardization is presented. It includes an over-view of U.S. and international status in such groups as the EIA P-6 and IEC SC-46E committees. The rationale for choosing the 4 tier system is explained, along with a table showing the structure of the system, as Basic, Generic, Sectional and Detail specifications. The implications of the recent OMB Circular A-119 on Federal Participation in the Development and Use of Voluntary Standards is discussed, particularly as it amplifies the already pressing question of adequate level of resource commitment to the standards question activity.

  9. KEYNOTE ADDRESS: The role of standards in the emerging optical digital data disk storage systems market

    Science.gov (United States)

    Bainbridge, Ross C.

    1984-09-01

    The Institute for Computer Sciences and Technology at the National Bureau of Standards is pleased to cooperate with the International Society for Optical Engineering and to join with the other distinguished organizations in cosponsoring this conference on applications of optical digital data disk storage systems.

  10. Comparison of intraocular lens power calculation using a standard ultrasonic biometer and a new optical biometer

    OpenAIRE

    Faruk Kaya; Ibrahim Koçak; Ali Aydin; Hakan Baybora; Koray Karadayi

    2016-01-01

    AIM:To compare the intraocular lens(IOL)power calculations and refractive outcomes obtained with a new optical biometer and standard ultrasonic biometer in phacoemulsification surgery.METHODS:Thirty-seven eyes of 37 cataract patients who underwent phacoemulsification with IOL implantation were included in this prospective comparative study. The same operator performed biometer measurements in eyes with cataract using a new optical biometer(Aladdin)and a standard ultrasonic biometer(Sonomed AB...

  11. Fast and cheap prototyping of non-standard optical components for sensing speckle dynamics

    DEFF Research Database (Denmark)

    Jakobsen, Michael Linde; Olesen, Anders Sig; Stubager, Jørgen

    2016-01-01

    As a part of the work carried out a project supported by the Danish council for technology and innovation, we have investigated the option of smoothening standard CNC machined surfaces. In the process of constructing optical prototypes, involving custom-designed optics, the development price...... and time can become a prohibitively large part of a research budget. Machining the optical surfaces of a molding tool may be done directly using diamond turning, but it is expensive and time consuming. Alternatively, a more standardized and cheaper machining method can be used, however, calling for manual...

  12. Scalable standard optical sources in the VUV: Emissions from electron impact on metals. [tantalum and tungsten

    Science.gov (United States)

    Hughes, R.

    1980-01-01

    The use of electron impact on metals in the development of a compact optical standard lamp in the vacuum ultraviolet is described. Two different mechanisms are exploited, transition radiation and bremsstrahlung. Transition radiation will be used as a primary standard from 1200A to 3000A using 10 keV electron impact on tungsten. Bremsstrahlung will be used in the soft X-ray region below 1200A to less than 5A as an optical transfer standard from 4 keV electron impact on tantalum or tungsten.

  13. Broadband single-mode operation of standard optical fibers by using a sub-wavelength optical wire filter.

    Science.gov (United States)

    Jung, Yongmin; Brambilla, Gilberto; Richardson, David J

    2008-09-15

    We report the use of a sub-wavelength optical wire (SOW) with a specifically designed transition region as an efficient tool to filter higher-order modes in multimode waveguides. Higher-order modes are effectively suppressed by controlling the transition taper profile and the diameter of the sub-wavelength optical wire. As a practical example, single-mode operation of a standard telecom optical fiber over a broad spectral window (400 approximately 1700 nm) was demonstrated with a 1microm SOW. The ability to obtain robust and stable single-mode operation over a very broad range of wavelengths offers new possibilities for mode control within fiber devices and is relevant to a range of application sectors including high performance fiber lasers, sensors, photolithography, and optical coherence tomography systems.

  14. Standard Hardware Acquisition and Reliability Program's (SHARP's) efforts in incorporating fiber optic interconnects into standard electronic module (SEM) connectors

    Science.gov (United States)

    Riggs, William R.

    1994-05-01

    SHARP is a Navy wide logistics technology development effort aimed at reducing the acquisition costs, support costs, and risks of military electronic weapon systems while increasing the performance capability, reliability, maintainability, and readiness of these systems. Lower life cycle costs for electronic hardware are achieved through technology transition, standardization, and reliability enhancement to improve system affordability and availability as well as enhancing fleet modernization. Advanced technology is transferred into the fleet through hardware specifications for weapon system building blocks of standard electronic modules, standard power systems, and standard electronic systems. The product lines are all defined with respect to their size, weight, I/O, environmental performance, and operational performance. This method of defining the standard is very conducive to inserting new technologies into systems using the standard hardware. This is the approach taken thus far in inserting photonic technologies into SHARP hardware. All of the efforts have been related to module packaging; i.e. interconnects, component packaging, and module developments. Fiber optic interconnects are discussed in this paper.

  15. A New Pumping-Probing Scheme for the Optically Pumped Cesium Beam Frequency Standard

    Institute of Scientific and Technical Information of China (English)

    陈景标; 朱程锦; 王凤芝; 杨东海

    2001-01-01

    A new pumping-probing scheme for the optically pumped cesium beam frequency standard has been experimentally tested in our laboratory. The stability of the optically pumped cesium beam frequency standard was measured by comparing its 10 MHz output with an HP5071A commercial cesium atomic clock. The result shows that the frequency stability for the 1 s and 30000s sample times are 1.2 × 10-11 and 3.7 × 10-13, respectively. It was proved that the new pumping scheme works well.

  16. Phase Analysis for Frequency Standards in the Microwave and Optical Domains.

    Science.gov (United States)

    Kazda, Michael; Gerginov, Vladislav; Huntemann, Nils; Lipphardt, Burghard; Weyers, Stefan

    2016-07-01

    Coherent manipulation of atomic states is a key concept in high-precision spectroscopy and used in atomic fountain clocks and a number of optical frequency standards. Operation of these standards can involve a number of cyclic switching processes, which may induce cycle-synchronous phase excursions of the interrogation signal and thus lead to shifts in the output of the frequency standard. We have built a field-programmable gate array (FPGA)-based phase analyzer to investigate these effects and conducted measurements on two kinds of frequency standards. For the caesium fountains PTB-CSF1 and PTB-CSF2, we were able to exclude phase variations of the microwave source at the level of a few microradians, corresponding to relative frequency shifts of less than [Formula: see text]. In the optical domain, we investigated phase variations in PTB's Yb (+) optical frequency standard and made detailed measurements of acousto-optic modulator (AOM) chirps and their scaling with duty cycle and driving power. We ascertained that cycle-synchronous as well as long-term phase excursion do not cause frequency shifts larger than [Formula: see text].

  17. [Development of a software standardizing optical density with operation settings related to several limitations].

    Science.gov (United States)

    Tu, Xiao-Ming; Zhang, Zuo-Heng; Wan, Cheng; Zheng, Yu; Xu, Jin-Mei; Zhang, Yuan-Yuan; Luo, Jian-Ping; Wu, Hai-Wei

    2012-12-01

    To develop a software that can be used to standardize optical density to normalize the procedures and results of standardization in order to effectively solve several problems generated during standardization of in-direct ELISA results. The software was designed based on the I-STOD method with operation settings to solve the problems that one might encounter during the standardization. Matlab GUI was used as a tool for the development. The software was tested with the results of the detection of sera of persons from schistosomiasis japonica endemic areas. I-STOD V1.0 (WINDOWS XP/WIN 7, 0.5 GB) was successfully developed to standardize optical density. A serial of serum samples from schistosomiasis japonica endemic areas were used to examine the operational effects of I-STOD V1.0 software. The results indicated that the software successfully overcame several problems including reliability of standard curve, applicable scope of samples and determination of dilution for samples outside the scope, so that I-STOD was performed more conveniently and the results of standardization were more consistent. I-STOD V1.0 is a professional software based on I-STOD. It can be easily operated and can effectively standardize the testing results of in-direct ELISA.

  18. Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies

    DEFF Research Database (Denmark)

    Tearney, Guillermo J; Regar, Evelyn; Akasaka, Takashi

    2012-01-01

    The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the interest of improving the di...

  19. Potential of electric quadrupole transitions in radium isotopes for single-ion optical frequency standards

    NARCIS (Netherlands)

    Versolato, O. O.; Wansbeek, L. W.; Jungmann, K.; Timmermans, R. G. E.; Willmann, L.; Wilschut, H. W.

    2011-01-01

    We explore the potential of the electric quadrupole transitions 7s (2)S(1/2)-(6)d (2)D(3/2), 6d (2)D(5/2) in radium isotopes as single-ion optical frequency standards. The frequency shifts of the clock transitions due to external fields and the corresponding uncertainties are calculated. Several

  20. Prospects of obtaining terawatt class infrared pulses using standard optical parametric amplification

    Science.gov (United States)

    Guo, Xiaoyang; Tokita, Shigeki; Tu, Xiaoniu; Zheng, Yanqing; Kawanaka, Junji

    2017-02-01

    We conceptually propose a standard optical parametric amplification system based on YCOB crystal to achieve terawatt (TW) class infrared (IR) pulses with 100 mJ level energy, which would be one order of magnitude more energetic and powerful than currently available IR pulses and suitable to generate high photon flux water window x-rays.

  1. Standard Practice for Optical Distortion and Deviation of Transparent Parts Using the Double-Exposure Method

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This photographic practice determines the optical distortion and deviation of a line of sight through a simple transparent part, such as a commercial aircraft windshield or a cabin window. This practice applies to essentially flat or nearly flat parts and may not be suitable for highly curved materials. 1.2 Test Method F 801 addresses optical deviation (angluar deviation) and Test Method F 2156 addresses optical distortion using grid line slope. These test methods should be used instead of Practice F 733 whenever practical. 1.3 This standard does not purport to address the safety concerns associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  2. Phase Analysis for Frequency Standards in the Microwave and Optical Domains

    CERN Document Server

    Kazda, M; Huntemann, N; Lipphardt, B; Weyers, S

    2015-01-01

    Coherent manipulation of atomic states is a key concept in high-precision spectroscopy and used in atomic fountain clocks and a number of optical frequency standards. Operation of these standards can involve a number of cyclic switching processes, which may induce cycle synchronous phase excursions of the interrogation signal and thus lead to shifts in the output of the frequency standard. We have built a FPGA-based phase analyzer to investigate these effects and conducted measurements on two frequency standards. For the caesium fountain PTB-CSF2 we were able to exclude phase variations of the microwave source at the level of a few $\\mu$rad, corresponding to relative frequency shifts of less than 10$^{-16}$. In the optical domain, we investigated phase variations in PTB's Yb$^+$ optical frequency standard and made detailed measurements of AOM chirps and their scaling with duty cycle and driving power. We ascertained that cycle-synchronous as well as long-term phase excursion do not cause frequency shifts larg...

  3. Optical levitation of a mirror for reaching the standard quantum limit

    Science.gov (United States)

    Michimura, Yuta; Kuwahara, Yuya; Ushiba, Takafumi; Matsumoto, Nobuyuki; Ando, Masaki

    2017-06-01

    We propose a new method to optically levitate a macroscopic mirror with two vertical Fabry-P{\\'e}rot cavities linearly aligned. This configuration gives the simplest possible optical levitation in which the number of laser beams used is the minimum of two. We demonstrate that reaching the standard quantum limit (SQL) of a displacement measurement with our system is feasible with current technology. The cavity geometry and the levitated mirror parameters are designed to ensure that the Brownian vibration of the mirror surface is smaller than the SQL. Our scheme provides a promising tool for testing macroscopic quantum mechanics.

  4. Second harmonic 423-nm laser generated by BIBO crystal for calcium optical frequency standard

    Institute of Scientific and Technical Information of China (English)

    Zhenhui Chen; Bo Lu; Zhixue Xu; Wei Zhuang; Chuang Yu; Deshui Yu; Kaikai Huang; Xuzong Chen; Jinbiao Chen

    2008-01-01

    Calcium is one prospective element for the modern optical frequency standard.The 423-nm transition line of calcium atoms has been widely used in laser slowing and laser cooling, the precise spectrum measurement, and the magnetic optical trapping (MOT).However, there is no any available commercial diode laser working at this wavelength.We built a 423-nm laser based on extra bow-tie cavity and by using a Brewster cut uncoated BIBO (BiB3O6) crystal, which worked at room temperature, with conversion efficiency of 3.75%, and a potential up to 20%.

  5. Light propagation beyond the mean-field theory of standard optics.

    Science.gov (United States)

    Javanainen, Juha; Ruostekoski, Janne

    2016-01-25

    With ready access to massive computer clusters we may now study light propagation in a dense cold atomic gas by means of basically exact numerical simulations. We report on a direct comparison between traditional optics, that is, electrodynamics of a polarizable medium, and numerical simulations in an elementary problem of light propagating through a slab of matter. The standard optics fails already at quite low atom densities, and the failure becomes dramatic when the average interatomic separation is reduced to around k(-1), where k is the wave number of resonant light. The difference between the two solutions originates from correlations between the atoms induced by light-mediated dipole-dipole interactions.

  6. Modelling a nonlinear optical switching in a standard photonic crystal fiber infiltrated with carbon disulfide

    Science.gov (United States)

    Munera, Natalia; Acuna Herrera, Rodrigo

    2016-06-01

    In this letter, a numerical analysis is developed for the propagation of ultrafast optical pulses through a standard photonic crystal fiber (PCF) consisting of two infiltrated holes using carbon disulfide (CS2). This material is a good choice since it has highly nonlinear properties, what makes it a good candidate for optical switching and broadband source at low power compared to traditional nonlinear fiber coupler. Based on supermodes theory, a set of generalized nonlinear equations is presented in order to study the propagation characteristics. It is shown in this letter that it is possible to get optical switching behavior at low power and how the dispersion, as well as, the two infiltrated holes separation influence this effect. Finally, we see that supercontinuum generation can be induced equally in both infiltrated holes despite no initial excitation at one hole.

  7. First international comparison of fountain primary frequency standards via a long distance optical fiber link

    Science.gov (United States)

    Guéna, J.; Weyers, S.; Abgrall, M.; Grebing, C.; Gerginov, V.; Rosenbusch, P.; Bize, S.; Lipphardt, B.; Denker, H.; Quintin, N.; Raupach, S. M. F.; Nicolodi, D.; Stefani, F.; Chiodo, N.; Koke, S.; Kuhl, A.; Wiotte, F.; Meynadier, F.; Camisard, E.; Chardonnet, C.; Le Coq, Y.; Lours, M.; Santarelli, G.; Amy-Klein, A.; Le Targat, R.; Lopez, O.; Pottie, P. E.; Grosche, G.

    2017-06-01

    We report on the first comparison of distant caesium fountain primary frequency standards (PFSs) via an optical fiber link. The 1415 km long optical link connects two PFSs at LNE-SYRTE (Laboratoire National de métrologie et d’Essais—SYstème de Références Temps-Espace) in Paris (France) with two at PTB (Physikalisch-Technische Bundesanstalt) in Braunschweig (Germany). For a long time, these PFSs have been major contributors to accuracy of the International Atomic Time (TAI), with stated accuracies of around 3× {{10}-16} . They have also been the references for a number of absolute measurements of clock transition frequencies in various optical frequency standards in view of a future redefinition of the second. The phase coherent optical frequency transfer via a stabilized telecom fiber link enables far better resolution than any other means of frequency transfer based on satellite links. The agreement for each pair of distant fountains compared is well within the combined uncertainty of a few 10-16 for all the comparisons, which fully supports the stated PFSs’ uncertainties. The comparison also includes a rubidium fountain frequency standard participating in the steering of TAI and enables a new absolute determination of the 87Rb ground state hyperfine transition frequency with an uncertainty of 3.1× {{10}-16} . This paper is dedicated to the memory of André Clairon, who passed away on 24 December 2015, for his pioneering and long-lasting efforts in atomic fountains. He also pioneered optical links from as early as 1997.

  8. Standard Test Method for Measuring Optical Distortion in Transparent Parts Using Grid Line Slope

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 When an observer looks through an aerospace transparency, relative optical distortion results, specifically in thick, highly angled, multilayered plastic parts. Distortion occurs in all transparencies but is especially critical to aerospace applications such as combat and commercial aircraft windscreens, canopies, or cabin windows. This is especially true during operations such as takeoff, landing, and aerial refueling. It is critical to be able to quantify optical distortion for procurement activities. 1.2 This test method covers the apparatus and procedures that are suitable for measuring the grid line slope (GLS) of transparent parts, including those that are small or large, thin or thick, flat or curved, or already installed. This test method is not recommended for raw material. 1.3 The values stated in SI units shall be regarded as the standard. The values given in parentheses are for information only. This standard does not purport to address all of the safety concerns, if any, associated with it...

  9. Alternative methods of optical diagnostics in the field of standardization and metrology

    Science.gov (United States)

    Constantinov, Boris I.; Pasechnic, Teodosie I.; Sircu, Sergiu

    2000-10-01

    An optical configuration based on the photothermoplastic recording (PTPR) is suggested for the operational optical diagnostics and standardization of the products in the real time scale. The presence of three or four PTPR cameras along the counter of the tested product makes it possible to investigate in the real-time scale not only the appearance of the internal defects, but also the influence of the condition of different units onto the condition of the whole system. Dry development of the images in the real-time scale and instant fixation of images on the photothermoplastic carriers (PTPC) followed by the computer analysis used to compare the product and the standard allow us to gain in time and areas.

  10. OIFITS 2: the 2nd version of the data exchange standard for optical interferometry

    Science.gov (United States)

    Duvert, Gilles; Young, John; Hummel, Christian A.

    2017-01-01

    This paper describes version 2 of the Optical Interferometry exchange Format (OIFITS), the standard for exchanging calibrated data from optical (visible or infrared) interferometers. This IAU-endorsed standard has been in use for 10 years at most of the past and current optical interferometer projects, including COAST, NPOI, IOTA, CHARA, VLTI, PTI and the Keck interferometer. Software is available for reading, writing and merging OIFITS files. This version 2 provides definitions of additional data tables (for example for polarisation measurements), addressing the needs of future interferometric instruments. Also included are data columns for a more rigorous description of measurement errors and their correlations. In that, this document is a step towards the design of a common data model for optical interferometry. Finally, the main OIFITS header is expanded with several new keywords summarising the content to allow doing data base searches. We request that comments and suggestions related to OIFITS be directed to the OLBIN email list. (See http://www.jmmc.fr/olbin-forum for information on how to subscribe and post to the list.)

  11. Development, characterization, and validation of an optical transfer standard for ammonia in air

    Science.gov (United States)

    Lüttschwager, Nils; Balslev-Harder, David; Leuenberger, Daiana; Pogány, Andrea; Werhahn, Olav; Ebert, Volker

    2017-04-01

    Ammonia is an atmospheric trace gas that is predominantly emitted from anthropogenic agricultural activities. Since elevated levels of ammonia can have negative effects to human health as well as ecosystems, it is imperative to monitor and control ammonia emissions. This requires SI-traceable standards to calibrate ammonia monitoring instrumentation and to make measurements comparable. The lack of such standards became a pressing issue in recent years and the MetNH3 project (www.metnh3.eu) was initiated to fill the gap, pursuing different strategies. The work that we present was part of these endeavours and focusses on the development and application of an optical transfer standard for amount fraction measurements of ammonia in ambient air. An optical transfer standard (OTS) offers an alternative to calibrations of air monitoring instrumentation by means of reference gas mixtures. With an OTS, absolute amount fraction results are derived by evaluating absorption spectra using a spectral model and pre-measured spectral properties of the analyte. In that way, the instrument can measure calibration gas-independent ("calibration-free") and, moreover, can itself serve as standard to calibrate air monitoring analyzers. Molecular spectral properties are the excellent, non-drifting point of reference of the OTS and form, together with traceable measurements of temperature and pressure, the basis for SI-traceable amount fraction measurements. We developed an OTS based on a commercial cavity-ring-down spectrometer with a detection limit below 1 ppb (1 nmol/mol). A custom spectral data evaluation routine for absolute, calibration-free measurements, as well as measurements of spectral properties of ammonia with the focus on measurement uncertainty and traceability [1] are the fundaments of our OTS. Validation measurements were conducted using a SI-traceable ammonia reference gas generator over a period of several months. Here, we present an evaluation of the performance of our

  12. A standard model eye with micro scale multilayer structure for ophthalmic optical coherence tomography equipment

    Science.gov (United States)

    Cao, Zhenggang; Ding, Zengqian; Hu, Zhixiong; Wen, Tao; Qiao, Wen; Liu, Wenli

    2016-10-01

    Optical coherence tomography (OCT) has been widely applied in diagnosis of eye diseases during the last 20 years. Differing from traditional two-dimension imaging technologies, OCT could also provide cross-sectional information of target tissues simultaneously and precisely. As well known, axial resolution is one of the most critical parameters impacting the OCT image quality, which determines whether an accurate diagnosis could be obtained. Therefore, it is important to evaluate the axial resolution of an OCT equipment. Phantoms always play an important role in the standardization and validation process. Here, a standard model eye with micro-scale multilayer structure was custom designed and manufactured. Mimicking a real human eye, analyzing the physical characteristic of layer structures of retina and cornea in-depth, appropriate materials were selected by testing the scattering coefficient of PDMS phantoms with difference concentration of TiO2 or BaSO4 particles. An artificial retina and cornea with multilayer-films which have a thickness of 10 to 60 micrometers for each layer were fabricated using spin coating technology. Considering key parameters of the standard model eye need to be traceable as well as accurate, the optical refractive index and layer structure thicknesses of phantoms were verified by utilizing Thickness Monitoring System. Consequently, a standard OCT model eye was obtained after the retinal or corneal phantom was embedded into a water-filled model eye which has been fabricated by 3D printing technology to simulate ocular dispersion and emmetropic refraction. The eye model was manufactured with a transparent resin to simulate realistic ophthalmic testing environment, and most key optical elements including cornea, lens and vitreous body were realized. By investigating with a research and a clinical OCT system respectively, the OCT model eye was demonstrated with similar physical properties as natural eye, and the multilayer film measurement

  13. Comparison of intraocular lens power calculation using a standard ultrasonic biometer and a new optical biometer

    Directory of Open Access Journals (Sweden)

    Faruk Kaya

    2016-05-01

    Full Text Available AIM:To compare the intraocular lens(IOLpower calculations and refractive outcomes obtained with a new optical biometer and standard ultrasonic biometer in phacoemulsification surgery.METHODS:Thirty-seven eyes of 37 cataract patients who underwent phacoemulsification with IOL implantation were included in this prospective comparative study. The same operator performed biometer measurements in eyes with cataract using a new optical biometer(Aladdinand a standard ultrasonic biometer(Sonomed AB 5500. Biometric parameters; axial length(AL, keratometric(Kreadings, anterior chamber depth(ACDand IOL power obtained by two devices were recorded. Postoperative actual refractive errors and errors predicted by two devices according to SRK/T formula were analyzed. The mean estimation error(EE, mean absolute estimation error(AEEand the biometric parameters obtained by two biometers were compared.RESULTS:The AL measured by Aladdin(23.45±0.73 mmwas significantly longer than AL by ultrasonic biometer(23.2±0.75 mm(P=0.01. The mean EE and AEE values obtained by Aladdin were significantly smaller than the values by ultrasonic biometer(P=0.0006 and 0.03 respectively. The higher percentage of eyes within ±0.5 and ±1.00 D of target refraction was also found by using Aladdin(67% and 97%.CONCLUSION:The Aladdin optical biometer showed better accuracy and yielded better refractive outcomes compared with ultrasonic biometer.

  14. Binary pseudorandom test standard to determine the modulation transfer function of optical microscopes

    Energy Technology Data Exchange (ETDEWEB)

    Novak, Erik; Trolinger, James D.; Lacey, Ian; Anderson, Erik H.; Artemiev, Nikolay A.; Babin, Sergey; Cabrini, Stefano; Calafiore, Guiseppe; Chan, Elaine R.; McKinney, Wayne R.; Peroz, Christophe; Takacs, Peter Z.; Yashchuk, Valeriy V.

    2015-09-01

    This work reports on the development of a binary pseudo-random test sample optimized to calibrate the MTF of optical microscopes. The sample consists of a number of 1-D and 2-D patterns, with different minimum sizes of spatial artifacts from 300 nm to 2 microns. We describe the mathematical background, fabrication process, data acquisition and analysis procedure to return spatial frequency based instrument calibration. We show that the developed samples satisfy the characteristics of a test standard: functionality, ease of specification and fabrication, reproducibility, and low sensitivity to manufacturing error. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  15. Optical influence of different standard illuminants on green nephrite's color From Manasi

    Science.gov (United States)

    Du, Hong-mei; Guo, Ying

    2010-11-01

    To evaluate the optical influence of illuminant on green color with low chroma (C*~1~12) of nephrite from Manasi, three different standard illuminant-daylight D65, incandescent light A and fluorescent light F2 (CWF) were applied during the experiment. Two-way ANOVA was used to analyze the illuminants tested considering the coordinates of lightness L* and chromaticity a*, b*. The results indicate significant differences for L*, a* and b* (pnephrite's color grading while light source A can be used during trading.

  16. Imaging of the optic disk in caring for patients with glaucoma: ophthalmoscopy and photography remain the gold standard.

    Science.gov (United States)

    Spaeth, George L; Reddy, Swathi C

    2014-01-01

    Optic disk imaging is integral to the diagnosis and treatment of patients with glaucoma. We discuss the various forms of imaging the optic nerve, including ophthalmoscopy, photography, and newer imaging modalities, including optical coherence tomography (OCT), confocal scanning laser ophthalmoscopy (HRT), and scanning laser polarimetry (GDx), specifically highlighting their benefits and disadvantages. We argue that ophthalmoscopy and photography remain the gold standard of imaging due to portability, ease of interpretation, and the presence of a large database of images for comparison.

  17. Application of Electron-Shelving Detection via 423 nm Transition in Calcium-Beam Optical Frequency Standard

    Institute of Scientific and Technical Information of China (English)

    HUANG Kai-Kai; ZHANG Jian-Wei; YU De-Shui; CHEN Zhen-Hui; ZHUAN Wei; CHEN Jing-Biao

    2006-01-01

    A new scheme of small compact optical frequency standard based on thermal calcium beam with application of 423 nm shelving detection and sharp-angle velocity selection detection is proposed. Combining these presented techniques, we conclude that a small compact optical frequency standard based on thermal calcium beam will outperform the commercial caesium-beam microwave clock, like the 5071 Cs clock (from HP to Agilent, now Symmetricom company), both in accuracy and stability.

  18. A monolithic, standard CMOS, fully differential optical receiver with an integrated MSM photodetector

    Institute of Scientific and Technical Information of China (English)

    Yu Changliang; Mao Luhong; Xiao Xindong; Xie Sheng; Zhang Shilin

    2009-01-01

    This paper presents a realization of a silicon-based standard CMOS, fully differential optoelectronic inte grated receiver based on a metal-semiconductor-metal light detector (MSM photodetector). In the optical receiver, two MSM photodetectors are integrated to convert the incident light signal into a pair of fully differential photo generated currents. The optoelectronic integrated receiver was designed and implemented in a chartered 0.35 μm, 3.3 V standard CMOS process. For 850 nm wavelength, it achieves a 1 GHz 3 dB bandwidth due to the MSM pho todetector's low capacitance and high intrinsic bandwidth. In addition, it has a transimpedance gain of 98.75 dBΩ, and an equivalent input integrated referred noise current of 283 nA from 1 Hz up to -3 dB frequency.

  19. Visual Performance and Optical Quality of Standardized Asymmetric Soft Contact Lenses in Patients With Keratoconus.

    Science.gov (United States)

    Suzaki, Asaki; Maeda, Naoyuki; Fuchihata, Mutsumi; Koh, Shizuka; Nishida, Kohji; Fujikado, Takashi

    2017-06-01

    To evaluate the visual performance and optical quality of a standardized asymmetric soft contact lens (SCL) used for correction of higher-order aberrations (HOAs) in eyes with keratoconus. We included 30 eyes (26 patients) with keratoconus (average K: 45.7 ± 2.3 diopters [D]). The patients were subjected to corneal tomography, aberrometry, measurements of manifest refraction and visual acuity (VA), and visual analog scale (VAS) assessments. The study lenses were made using a molding method and consisted of six standardized types, in which an asymmetric power distribution of approximately 2 to 12 D (2-D step) was used to correct HOAs. The lens type suitable for each eye was selected based on the corneal tomography and aberrometry data. The on-eye performance of the lens was evaluated using aberrometry (4-mm pupil), over refraction, VA, and VAS. The standardized asymmetric SCL improved the best spectacle-corrected VA from -0.07 ± 0.09 to -0.11 ± 0.08 logMAR (P keratoconus who wear rigid gas-permeable lenses.

  20. Optical codeword demodulation with error rates below standard quantum limit using a conditional nulling receiver

    CERN Document Server

    Chen, Jian; Dutton, Zachary; Lazarus, Richard; Guha, Saikat

    2011-01-01

    The quantum states of two laser pulses---coherent states---are never mutually orthogonal, making perfect discrimination impossible. Even so, coherent states can achieve the ultimate quantum limit for capacity of a classical channel, the Holevo capacity. Attaining this requires the receiver to make joint-detection measurements on long codeword blocks, optical implementations of which remain unknown. We report the first experimental demonstration of a joint-detection receiver, demodulating quaternary pulse-position-modulation (PPM) codewords at a word error rate of up to 40% (2.2 dB) below that attained with direct-detection, the largest error-rate improvement over the standard quantum limit reported to date. This is accomplished with a conditional nulling receiver, which uses optimized-amplitude coherent pulse nulling, single photon detection and quantum feedforward. We further show how this translates into coding complexity improvements for practical PPM systems, such as in deep-space communication. We antici...

  1. Laser system for Doppler cooling of ytterbium ion in an optical frequency standard

    Energy Technology Data Exchange (ETDEWEB)

    Chepurov, S V; Lugovoy, A A; Kuznetsov, S N [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2014-06-30

    A laser system for Doppler cooling of ytterbium ion on the {sup 2}S{sub 1/2} → {sup 2}P{sub 1/2} transition in a single-ion optical frequency standard is developed. The second harmonic of a semiconductor laser with a wavelength of 739 nm is used for cooling. The laser frequency is doubled in a nonlinear BiBO crystal embedded in a ring resonator, which also serves as a reference for laser frequency stabilisation. Second-harmonic power of ∼100 μW is generated at a wavelength of 369.5 nm. Diode laser radiation is modulated by an electro-optic modulator at 14.75 GHz to generate a sideband exciting the {sup 2}S{sub 1/2} (F = 0) → {sup 2}P{sub 1/2} (F = 1) hyperfine component of the cooling transition that is not excited by resonant cooling light. The sideband relative intensity of a few percent proved to be sufficient to reduce the ion dwelling time in the {sup 2}S{sub 1/2} (F = 0) state to less than 10{sup -4} s and increase the cooling efficiency. (extreme light fields and their applications)

  2. Mt. Graham: Optical turbulence vertical distribution at standard and high vertical resolution

    CERN Document Server

    Masciadri, E; Hagelin, S; S.,; Lascaux, F; di Arcetri, INAF - Osservatorio Astrofisico; 10.1117/12.856904

    2010-01-01

    A characterization of the optical turbulence vertical distribution and all the main integrated astroclimatic parameters derived from the CN2 and the wind speed profiles above Mt. Graham is presented. The statistic includes measurements related to 43 nights done with a Generalized Scidar (GS) used in standard configuration with a vertical resolution of ~1 km on the whole 20-22 km and with the new technique (HVR-GS) in the first kilometer. The latter achieves a resolution of ~ 20-30 m in this region of the atmosphere. Measurements done in different periods of the year permit us to provide a seasonal variation analysis of the CN2. A discretized distribution of the typical CN2 profiles useful for the Ground Layer Adaptive Optics (GLAO) simulations is provided and a specific analysis for the LBT Laser Guide Star system ARGOS case is done including the calculation of the 'gray zones' for J, H and K bands. Mt. Graham confirms to be an excellent site with median values of the seeing without dome contribution equal to...

  3. New bright optical spectrophotometric standards: A-type stars from the STIS Next Generation Spectral Library

    CERN Document Server

    Prieto, Carlos Allende

    2015-01-01

    Exoplanets have sparked interest in extremely high signal-to-noise ratio spectroscopic observations of very bright stars, in a regime where flux calibrators, in particular DA white dwarfs, are not available. We argue that A-type stars offer a useful alternative and reliable space-based spectrophotometry is now available for a number of bright ones in the range 3standards for the optical range (400-800 nm), and provide scaled model fluxes for them. Our tests suggest that the absolute fluxes for these stars in the optical are reliable to within 3%. We limit the spectral range to 400-800 nm, since our models have difficulties to reproduce the observed fluxes in the near-infrared and, especially, in the near-UV, where the discrepancies rise up to ~ 10%. Based on our model fits, we derive angular diameters with an estimated accuracy of about 1%.

  4. Analysis of thermal radiation in ion traps for optical frequency standards

    CERN Document Server

    Doležal, Miroslav; Nisbet-Jones, Peter B R; King, Steven A; Jones, Jonathan M; Klein, Hugh A; Gill, Patrick; Lindvall, Thomas; Wallin, Anders E; Merimaa, Mikko; Tamm, Christian; Sanner, Christian; Huntemann, Nils; Scharnhorst, Nils; Leroux, Ian D; Schmidt, Piet O; Burgermeister, Tobias; Mehlstäubler, Tanja E; Peik, Ekkehard

    2015-01-01

    In many of the high-precision optical frequency standards with trapped atoms or ions that are under development to date, the AC Stark shift induced by thermal radiation leads to a major contribution to the systematic uncertainty. We present an analysis of the inhomogeneous thermal environment experienced by ions in various types of ion traps. Finite element models which allow the determination of the temperature of the trap structure and the temperature of the radiation were developed for 5 ion trap designs, including operational traps at PTB and NPL and further optimized designs. Models were refined based on comparison with infrared camera measurement until an agreement of better than 10% of the measured temperature rise at critical test points was reached. The effective temperature rises of the radiation seen by the ion range from 0.8 K to 2.1 K at standard working conditions. The corresponding fractional frequency shift uncertainties resulting from the uncertainty in temperature are in the 10-18 range for ...

  5. CONFERENCE NOTE: CETO—Centro de Ciências e Tecnologias Opticas, Trends in Optical Fibre Metrology and Standards

    Science.gov (United States)

    1994-01-01

    Summer School, 27 June to 8 July 1994, Viana do Castelo, Hotel do Parque, Portugal Optical fibres, with their extremely low transmission loss, untapped bandwidth and controllable dispersion, dominate a broad range of technologies in which applications must respond to the increasing constraints of today's specifications as well as envisage future requirements. Optical fibres dominate communications systems. In the area of sensors, fibre optics will be fully exploited for their immunity to EMI, their high sensitivity and their large dynamic range. The maturity of single mode optical technology has led to intensive R&D of a range of components based on the advantages of transmission characteristics and signal processing. Specifications and intercompatibility requests for the new generation of both analogue and digital fibre optical components and systems has created a demand for sophisticated measuring techniques based on unique and complex instruments. In recent years there has been a signification evolution in response to the explosion of applications and the tightening of specifications. These developments justify a concerted effort to focus on trends in optical fibre metrology and standards. Objective The objective of this school is to provide a progressive and comprehensive presentation of current issues concerning passive and active optical fibre characterization and measurement techniques. Passive fibre components support a variety of developments in optical fibre systems and will be discussed in terms of relevance and standards. Particular attention will be paid to devices for metrological purposes such as reference fibres and calibration artefacts. The characterization and testing of optical fibre amplifiers, which have great potential in telecommunications, data distribution networks and as a system part in instrumentation, will be covered. Methods of measurement and means of calibration with traceability will be discussed, together with the characterization

  6. Standardization of choroidal thickness measurements using enhanced depth imaging optical coherence tomography

    Institute of Scientific and Technical Information of China (English)

    Nattapon; Boonarpha; Yalin; Zheng; Alexandros; N.Stangos; Huiqi; Lu; Ankur; Raj; Gabriela; Czanner; Simon; P.Harding; Jayashree; Nair-Sahni

    2015-01-01

    AIM: To describe and evaluate a standardized protocol for measuring the choroidal thickness(Ch T) using enhanced depth imaging optical coherence tomography(EDI OCT).METHODS: Single 9 mm EDI OCT line scans across the fovea were used for this study. The protocol used in this study classified the EDI OCT images into four groups based on the appearance of the choroidal-scleral interface and suprachoroidal space. Two evaluation iterations of experiments were performed: first, the protocol was validated in a pilot study of 12 healthy eyes. Afterwards, the applicability of the protocol was tested in 82 eyes of patients with diabetes. Inter-observer and intra-observer agreements on image classifications were performed using Cohen’s kappa coefficient(κ). Intraclass correlation coefficient(ICC) and Bland-Altman’s methodology were used for the measurement of the Ch T.RESULTS: There was a moderate(κ=0.42) and perfect(κ =1) inter- and intra-observer agreements on image classifications from healthy eyes images and substantial(κ =0.66) and almost perfect(κ =0.86) agreements from diabetic eyes images. The proposed protocol showed excellent inter- and intra-observer agreements for the Ch T measurements on both, healthy eyes and diabetic eyes(ICC >0.90 in all image categories). The Bland-Altman plot showed a relatively large Ch T measurement agreement in the scans that contained less visible choroidal outer boundary. CONCLUSION: A protocol to standardize Ch T measurements in EDI OCT images has been developed;the results obtained using this protocol show that the technique is accurate and reliable for routine clinical practice and research.

  7. Standardization of choroidal thickness measurements using enhanced depth imaging optical coherence tomography

    Directory of Open Access Journals (Sweden)

    Nattapon Boonarpha

    2015-06-01

    Full Text Available AIM:To describe and evaluate a standardized protocol for measuring the choroidal thickness (ChT using enhanced depth imaging optical coherence tomography (EDI OCT.METHODS:Single 9 mm EDI OCT line scans across the fovea were used for this study. The protocol used in this study classified the EDI OCT images into four groups based on the appearance of the choroidal-scleral interface and suprachoroidal space. Two evaluation iterations of experiments were performed:first, the protocol was validated in a pilot study of 12 healthy eyes. Afterwards, the applicability of the protocol was tested in 82 eyes of patients with diabetes. Inter-observer and intra-observer agreements on image classifications were performed using Cohen’s kappa coefficient (k. Intraclass correlation coefficient (ICC and Bland-Altman’s methodology were used for the measurement of the ChT.RESULTS:There was a moderate (k=0.42 and perfect (k=1 inter- and intra-observer agreements on image classifications from healthy eyes images and substantial (k=0.66 and almost perfect (k=0.86 agreements from diabetic eyes images. The proposed protocol showed excellent inter- and intra-observer agreements for the ChT measurements on both, healthy eyes and diabetic eyes (ICC>0.90 in all image categories. The Bland-Altman plot showed a relatively large ChT measurement agreement in the scans that contained less visible choroidal outer boundary.CONCLUSIONS:A protocol to standardize ChT measurements in EDI OCT images has been developed; the results obtained using this protocol show that the technique is accurate and reliable for routine clinical practice and research.

  8. OIFITS 2: the 2nd version of the Data Exchange Standard for Optical (Visible/IR) Interferometry

    CERN Document Server

    Duvert, Gilles; Hummel, Christian

    2015-01-01

    This paper describes version 2 of the OI Exchange Format (OIFITS), the standard for exchanging calibrated data from optical (visible/infrared) interferometers. This IAU-endorsed standard has been in use for 10 years at most of the past and current optical interferometer projects, including COAST, NPOI, IOTA, CHARA, VLTI, PTI and the Keck interferometer. Software is available for reading, writing and merging OI Exchange Format files. This version 2 provides definitions of additional data tables (e.g. for polarisation measurements), addressing the needs of future interferometric instruments. Also included are data columns for a more rigorous description of measurement errors and their correlations. In that, this document is a step towards the design of a common data model for optical interferometry. Finally, the main OIFITS header is expanded with several new keywords summarising the content to allow data base searches.

  9. A Unified Model for GRB Prompt Emission from Optical to Gamma-Rays; a New Type of Standard Candle

    CERN Document Server

    Guiriec, S; Hartmann, D H; Granot, J; Asano, K; Meszaros, P; Gill, R; Gehrels, N; McEnery, J

    2016-01-01

    The origin of prompt emission from gamma ray bursts remains to be an open question. Correlated prompt optical and gamma-ray emission observed in a handful of GRBs strongly suggests a common emission region, but failure to adequately fit the broadband GRB spectrum prompted the hypothesis of different emission mechanisms for the low- and high-energy radiations. We demonstrate that our multi-component model for GRB gamma-ray prompt emission provides an excellent fit to GRB 110205A from optical to gamma-ray energies. Our results show that the optical and highest gamma-ray emissions have the same spatial and spectral origin, which is different from the bulk of the X- and softest gamma-ray radiation. Finally, our accurate redshift estimate for GRB 110205A demonstrates promise for using GRBs as cosmological standard candles.

  10. National Institute of Standards and Technology measurement service of the optical properties of biomedical phantoms: current status

    Science.gov (United States)

    Lemaillet, Paul; Cooksey, Catherine C.; Levine, Zachary H.; Pintar, Adam L.; Hwang, Jeeseong; Allen, David W.

    2016-03-01

    The National Institute of Standards and Technology (NIST) has maintained scales for reflectance and transmittance over several decades. The scales are primarily intended for regular transmittance, mirrors, and solid surface scattering diffusers. The rapidly growing area of optical medical imaging needs a scale for volume scattering of diffuse materials that are used to mimic the optical properties of tissue. Such materials are used as phantoms to evaluate and validate instruments under development intended for clinical use. To address this need, a double-integrating sphere based instrument has been installed to measure the optical properties of tissue-mimicking phantoms. The basic system and methods have been described in previous papers. An important attribute in establishing a viable calibration service is the estimation of measurement uncertainties. The use of custom models and comparisons with other established scales enabled uncertainty measurements. Here, we describe the continuation of those efforts to advance the understanding of the uncertainties through two independent measurements: the bidirectional reflectance distribution function and the bidirectional transmittance distribution function of a commercially available solid biomedical phantom. A Monte Carlo-based model is used and the resulting optical properties are compared to the values provided by the phantom manufacturer.

  11. Integration and fusion of standard automated perimetry and optical coherence tomography data for improved automated glaucoma diagnostics

    Directory of Open Access Journals (Sweden)

    Bizios Dimitrios

    2011-08-01

    Full Text Available Abstract Background The performance of glaucoma diagnostic systems could be conceivably improved by the integration of functional and structural test measurements that provide relevant and complementary information for reaching a diagnosis. The purpose of this study was to investigate the performance of data fusion methods and techniques for simple combination of Standard Automated Perimetry (SAP and Optical Coherence Tomography (OCT data for the diagnosis of glaucoma using Artificial Neural Networks (ANNs. Methods Humphrey 24-2 SITA standard SAP and StratusOCT tests were prospectively collected from a randomly selected population of 125 healthy persons and 135 patients with glaucomatous optic nerve heads and used as input for the ANNs. We tested commercially available standard parameters as well as novel ones (fused OCT and SAP data that exploit the spatial relationship between visual field areas and sectors of the OCT peripapillary scan circle. We evaluated the performance of these SAP and OCT derived parameters both separately and in combination. Results The diagnostic accuracy from a combination of fused SAP and OCT data (95.39% was higher than that of the best conventional parameters of either instrument, i.e. SAP Glaucoma Hemifield Test (p Conclusions Compared to the use of SAP parameters, input from the combination of fused OCT and SAP parameters, and from fused OCT data, significantly increased the performance of ANNs. Integrating parameters by including a priori relevant information through data fusion may improve ANN classification accuracy compared to currently available methods.

  12. The need for a single cleaning standard for OEM and OSP fiber optic connections

    Science.gov (United States)

    Forrest, Edward J., Jr.; Blair, Paul

    2009-01-01

    Development of fiber optic communications networks has continued in virtually all geographies of the world. Some calculate that expansion in the USA alone will continue to 2025. After that time there will maintenance, upgrade, and replacement. While some nations are more advanced than others and some enterprises more sophisticated than others, the undeniable reality is that previous networks will, in some fashion or another, include fiber optics. The future need is for speed and reliable bandwidth: lots of it. Decisions will be made based on new concepts that will enable far more data at far faster rates than once considered feasible or necessary. As the consumer enters the market with newly engineered home entertainment systems, additional burdens will be placed on both OEM and OSP. These are not negative challenges, but rather indicators of a new generation of consumers with awareness and demand far more advanced any may have imagined just a few years ago.

  13. Transmission of 10 GHz,3.5 ps Optical Pulses Over 100-km Standard Fiber Using Mid-span Spectral Inversion

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jianfeng; YAO Minyu; PENG Can; ZHANG Hongming; XU Qianfan; GAO Yizhi

    2002-01-01

    Transmission of 3.5ps optical pulses over 100-km standard fiber was demonstrated by employing phase conjugation in a semiconductor optical amplifier to compensate the chromatic dispersion.The pulses were broadened to 5 ps after transmission,which confirms the applicability of this technique to ultra high-bit-rate system beyond 40 Gb/s.

  14. Portable optical frequency standard based on sealed gas-filled hollow-core fiber using a novel encapsulation technique

    DEFF Research Database (Denmark)

    Triches, Marco; Brusch, Anders; Hald, Jan

    2015-01-01

    A portable stand-alone optical frequency standard based on a gas-filled hollow-core photonic crystal fiber is developed to stabilize a fiber laser to the 13C2H2 P(16) (ν1 + ν3) transition at 1542 nm using saturated absorption. A novel encapsulation technique is developed to permanently seal...... the hollow-core fiber with easy light coupling, showing negligible pressure increase over two months. The locked laser shows a fractional frequency instability below 8 × 10−12 for an averaging time up to 104 s. The lock-point repeatability over one month is 2.6 × 10−11, corresponding to a standard deviation...

  15. Standard Test Method for Dust Erosion Resistance of Optical and Infrared Transparent Materials and Coatings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the resistance of transparent plastics and coatings used in aerospace windscreens, canopies, and viewports to surface erosion as a result of dust impingement. This test method simulates flight through a defined particle cloud environment by means of independent control of particle size, velocity, impact angle, mass loading, and test duration. 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  16. Automatable on-line generation of calibration curves and standard additions in solution-cathode glow discharge optical emission spectrometry

    Science.gov (United States)

    Schwartz, Andrew J.; Ray, Steven J.; Hieftje, Gary M.

    2015-03-01

    Two methods are described that enable on-line generation of calibration standards and standard additions in solution-cathode glow discharge optical emission spectrometry (SCGD-OES). The first method employs a gradient high-performance liquid chromatography pump to perform on-line mixing and delivery of a stock standard, sample solution, and diluent to achieve a desired solution composition. The second method makes use of a simpler system of three peristaltic pumps to perform the same function of on-line solution mixing. Both methods can be computer-controlled and automated, and thereby enable both simple and standard-addition calibrations to be rapidly performed on-line. Performance of the on-line approaches is shown to be comparable to that of traditional methods of sample preparation, in terms of calibration curves, signal stability, accuracy, and limits of detection. Potential drawbacks to the on-line procedures include signal lag between changes in solution composition and pump-induced multiplicative noise. Though the new on-line methods were applied here to SCGD-OES to improve sample throughput, they are not limited in application to only SCGD-OES-any instrument that samples from flowing solution streams (flame atomic absorption spectrometry, ICP-OES, ICP-mass spectrometry, etc.) could benefit from them.

  17. Polarization-Independent High-Speed Switching in a Standard Non-Linear Optical Loop Mirror

    DEFF Research Database (Denmark)

    Mulvad, Hans Christian Hansen; Galili, Michael; Oxenløwe, Leif Katsuo

    2008-01-01

    We introduce a scheme which allows polarization-independent switching in a standard NOLM. Experimental verification is performed by switching 10 Gbit/s data with 0.2 dB polarization-dependence and by error-free demultiplexing of polarization-scrambled 320 Gbit/s OTDM data....

  18. Surpassing the standard quantum limit for optical imaging using nonclassical multimode light

    DEFF Research Database (Denmark)

    Treps, N.; Andersen, Ulrik Lund; Buchler, B.

    2002-01-01

    Using continuous wave superposition of spatial modes, we demonstrate experimentally displacement measurement of a light beam below the standard quantum limit. Multimode squeezed light is obtained by mixing a vacuum squeezed beam and a coherent beam that are spatially orthogonal. Although...

  19. 7 CFR 1755.200 - RUS standard for splicing copper and fiber optic cables.

    Science.gov (United States)

    2010-01-01

    ... splices. (2) American National Standard Institute/National Fire Protection Association (ANSI/NFPA) 70... cable sheath and cable filling compound are susceptible to fire and will support combustion. Fire, smoke... be any damage to the buffer tubes. The jacket shall be peeled back and cut at the end of the...

  20. Recent standardization activities for client and networking optical transceivers and its future directions

    Science.gov (United States)

    Isono, Hideki

    2017-01-01

    In order to meet the recent vast demands of ICT bandwidth, high speed transmission systems, such as 100G, 200G and 400G, have been developed and installed with extremely high pace. De-fact standardization bodies such as IEEE802.3/OIF have played important roles in the industry for leading the proper concepts/designs of the leading edge high speed transceivers. Reviewing the recent activities of these standardization bodies, the future migration towards 800G and 1.6T with small form factor transceivers are examined. The high bandwidth per channel technology, such as 100GHz and beyond, is a key factor to realize the next generation transceivers such as 800G and 1.6T.

  1. Fiber laser optical frequency standard at 1.54 μm.

    Science.gov (United States)

    Hald, Jan; Nielsen, Lars; Petersen, Jan C; Varming, Poul; Pedersen, Jens E

    2011-01-31

    A 32 mW fiber laser is stabilized to the (13)C(2)H(2) P(16) (ν1 + ν3) transition at 1542 nm using saturated absorption. The short-term shot-noise limited fractional frequency instability is 5.0 × 10(-13)(τ/s)-½ for averaging times τ up to about 100 s. The relative lock-point repeatability over 2½ month is 4.3 × 10(-13) corresponding to 83 Hz. The simple setup includes a 21 cm long gas cell, but it does not require an enhancement cavity or external modulators. The spectroscopic lineshape is analyzed with respect to optical power and acetylene pressure. Narrow linewidths of 300 kHz FWHM are observed with a signal to noise ratio of 35 dB in a 9 Hz bandwidth.

  2. 光纤光缆主要的环境保护标准%Brief analysis of the main optical fiber and cable environmental protection standards

    Institute of Scientific and Technical Information of China (English)

    袁峰; 詹朗朗; 吴金华; 顾利国

    2014-01-01

    This paper introduces several domestic and international environmental standards of protection of optical fiber and cable, and makes a brief analysis for standard. On this basis the paper mainly compares EU RoHS standard with ours, thus to adjust the direction of environmental protection and plan for the future development and progress of optical fiber and cable enterprises.%本文介绍了几种国内外的光纤光缆环境保护标准,并对于标准做了简要分析。在此基础上重点比较欧盟和国内的RoHS标准。

  3. Optics

    CERN Document Server

    Fincham, W H A

    2013-01-01

    Optics: Ninth Edition Optics: Ninth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommen

  4. Automated standardized pupillometry with optical method for purposes of clinical practice and research.

    Science.gov (United States)

    Fotiou, F; Fountoulakis, K N; Goulas, A; Alexopoulos, L; Palikaras, A

    2000-09-01

    The aim of the current study was the introduction and standardization of two experimental conditions for dynamic pupillometry. Pupillometry is a method that can provide valuable data concerning the functioning of the autonomous nervous system. The system for recording the pupil reaction was developed in the Laboratory of Clinical Neurophysiology of the 1st Department of Neurology of Aristotle University of Thessaloniki, in co-operation with the Laboratory of Fluid Mechanics of the Aristotle University of Thessaloniki. This system is fully automated. It includes an infra-red video camera, which has the capacity to record in complete darkness, and an SLE (clinical photic stimulator) lamp. A software application automatically performed all the procedures. During the first experiment, one flash was administered. During the second experiment, a series of 25 flashes (1 Hz frequency) was administered. Fifty physically and mentally healthy subjects aged 23-48 years took part in the study. Means, standard deviations and ranges for all variables characterizing normal subjects during both experimental conditions are reported. Test/re-test results and comparisons of the two eyes are also reported. The combined use of these two experimental conditions in dynamic pupillometry may be a very useful tool in medical research. There are already reports on the usefulness of pupillometry in the research of various diseases, including depression and Alzheimer's disease. It is expected that it will also be a valuable research tool in the study of diabetes, alcoholism, myasthenia gravis, cancer, multiple sclerosis, etc.

  5. Subcellular in vivo time-lapse imaging and optical manipulation of Caenorhabditis elegans in standard multiwell plates.

    Science.gov (United States)

    Rohde, Christopher B; Yanik, Mehmet Fatih

    2011-01-01

    High-resolution in vivo time-lapse assays require repeated immobilization and imaging of whole animals. Here we report a technology for screening Caenorhabditis elegans at cellular resolution over its entire lifespan inside standard multiwell plates using repeated immobilization, imaging and optical manipulation. Our system does not use any fluidic or mechanical components, and can operate for tens of thousands of cycles without failure. It is also compatible with industrial high-throughput screening platforms and robotics, and it allows both chemical, and forward and reverse genetic screens. We used this technology to perform subcellular-resolution femtosecond laser microsurgery of single neurons in vivo, and to image the subsequent regeneration dynamics at subcellular resolution. Our single-neuron in vivo time-lapse analysis shows that neurite regrowth occurring over short time windows is significantly greater than that predicted by ensemble averaging over many animals.

  6. Optical design and Initial Results from The National Institute of Standards and Technology’s AMMT/TEMPS Facility

    Science.gov (United States)

    Grantham, Steven; Lane, Brandon; Neira, Jorge; Mekhontsev, Sergey; Vlasea, Mihaela; Hanssen, Leonard

    2017-01-01

    The National Institute of Standards and Technology’s (NIST) Physical Measurement and Engineering Laboratories are jointly developing the Additive Manufacturing Measurement Testbed (AMMT)/ Temperature and Emittance of Melts, Powders and Solids (TEMPS) facilities. These facilities will be co-located on an open architecture laser-based powder bed fusion system allowing users full access to the system’s operation parameters. This will provide users with access to machine-independent monitoring and control of the powder bed fusion process. In this paper there will be emphasis on the AMMT, which incorporates in-line visible light collection optics for monitoring and feedback control of the powder bed fusion process. We shall present an overview of the AMMT/TEMPS program and its goals. The optical and mechanical design of the open architecture powder-bed fusion system and the AMMT will also be described. In addition, preliminary measurement results from the system along with the current status of the system will be described. PMID:28579666

  7. Optical-sectioning microscopy of protoporphyrin IX fluorescence in human gliomas: standardization and quantitative comparison with histology

    Science.gov (United States)

    Wei, Linpeng; Chen, Ye; Yin, Chengbo; Borwege, Sabine; Sanai, Nader; Liu, Jonathan T. C.

    2017-04-01

    Systemic delivery of 5-aminolevulinic acid leads to enhanced fluorescence image contrast in many tumors due to the increased accumulation of protoporphyrin IX (PpIX), a fluorescent porphyrin that is associated with tumor burden and proliferation. The value of PpIX-guided resection of malignant gliomas has been demonstrated in prospective randomized clinical studies in which a twofold greater extent of resection and improved progression-free survival have been observed. In low-grade gliomas and at the diffuse infiltrative margins of all gliomas, PpIX fluorescence is often too weak to be detected with current low-resolution surgical microscopes that are used in operating rooms. However, it has been demonstrated that high-resolution optical-sectioning microscopes are capable of detecting the sparse and punctate accumulations of PpIX that are undetectable via conventional low-power surgical fluorescence microscopes. To standardize the performance of high-resolution optical-sectioning devices for future clinical use, we have developed an imaging phantom and methods to ensure that the imaging of PpIX-expressing brain tissues can be performed reproducibly. Ex vivo imaging studies with a dual-axis confocal microscope demonstrate that these methods enable the acquisition of images from unsectioned human brain tissues that quantitatively and consistently correlate with images of histologically processed tissue sections.

  8. Relationship between Spectral-Domain Optical Coherence Tomography and Standard Automated Perimetry in Healthy and Glaucoma Patients

    Directory of Open Access Journals (Sweden)

    Beatriz Abadia

    2014-01-01

    Full Text Available Objective. To evaluate the relationship between spectral-domain optical coherence tomography (OCT and standard automated perimetry (SAP in healthy and glaucoma individuals. Methods. The sample comprised 338 individuals divided into 2 groups according to intraocular pressure and visual field outcomes. All participants underwent a reliable SAP and imaging of the optic nerve head with the Cirrus OCT. Pearson correlations were calculated between threshold sensitivity values of SAP (converted to linear scale and OCT parameters. Results. Mean age did not differ between the control and glaucoma groups (59.55 ± 9.7 years and 61.05 ± 9.4 years, resp.; P=0.15. Significant differences were found for the threshold sensitivities at each of the 52 points evaluated with SAP (P<0.001 and the peripapillary retinal nerve fiber layer (RNFL thicknesses, except at 3 and 9 clock-hour positions between both groups. Mild to moderate correlations (ranging between 0.286 and 0.593; P<0.001 were observed between SAP and most OCT parameters in the glaucoma group. The strongest correlations were found between the inferior RNFL thickness and the superior hemifield points. The healthy group showed lower and weaker correlations than the glaucoma group. Conclusions. Peripapillary RNFL thickness measured with Cirrus OCT showed mild to moderate correlations with SAP in glaucoma patients.

  9. Optics

    CERN Document Server

    Fincham, W H A

    2013-01-01

    Optics: Eighth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommended for engineering st

  10. Adding Papillomacular Bundle Measurements to Standard Optical Coherence Tomography Does Not Increase Sensitivity to Detect Prior Optic Neuritis in Patients with Multiple Sclerosis.

    Directory of Open Access Journals (Sweden)

    Mona Laible

    Full Text Available To improve the detection of retinal nerve fiber layer (RNFL thinning in multiple sclerosis (MS, a special peripapillary ring scanning algorithm (N-site RNFL, N-RNFL was developed for spectral domain optical coherence tomography (SD-OCT. In contrast to the standard protocol (ST-RNFL scanning starts nasally, not temporally, and provides an additional sector of analysis, the papillomacular bundle (PMB. We aimed to ascertain whether the temporal RNFL differs between the two techniques, whether N-RNFL is more sensitive than ST-RNFL to detect previous optic neuritis (ON, and whether analyzing the PMB adds additional sensitivity. Furthermore, we investigated whether RNFL is associated with disease severity and/or disease duration.We conducted a cross-sectional case-control study of 38 patients with MS, of whom 24 had a history of ON, and 40 healthy controls (HC. Subjects with ON within the previous 6 months were excluded. Records included clinical characteristics, visual evoked potentials (VEP, and SD-OCT in both techniques.In a total of 73 evaluable MS eyes, temporal N-RNFL was abnormal in 17.8%, temporal ST-RNFL in 19.2%, and the PMB-RNFL in 21.9%. In ON eyes, the sensitivity of temporal N-RNFL and ST-RNFL did not differ significantly (37.0%/33.3%, p = 0.556. The sensitivity of VEP was 85.2%. RNFL thickness was associated with disease severity in all eyes, with and without a history of ON, and with disease duration.The two OCT techniques detected previous ON with similar sensitivity, but the sensitivity of VEPs was superior to that of both N-RNFL and ST-RNFL. Our results indicate that the widely used ST-RNFL technique is appropriate for peripapillary RNFL measurements in MS patients.

  11. Wireless multipoint communication for optical sensors in the industrial environment using the new Bluetooth standard

    Science.gov (United States)

    Hussmann, Stephan; Lau, Wing Y.; Chu, Terry; Grothof, Markus

    2003-07-01

    Traditionally, the measuring or monitoring system of manufacturing industries uses sensors, computers and screens for their quality control (Q.C.). The acquired information is fed back to the control room by wires, which - for obvious reason - are not suitable in many environments. This paper describes a method to solve this problem by employing the new Bluetooth technology to set up a complete new system, where a total wireless solution is made feasible. This new Q.C. system allows several line scan cameras to be connected at once to a graphical user interface (GUI) that can monitor the production process. There are many Bluetooth devices available on the market such as cell-phones, headsets, printers, PDA etc. However, the detailed application is a novel implementation in the industrial Q.C. area. This paper will contain more details about the Bluetooth standard and why it is used (nework topologies, host controller interface, data rates, etc.), the Bluetooth implemetation in the microcontroller of the line scan camera, and the GUI and its features.

  12. Erratum: ``Optical Multicolor Photometry of Spectrophotometric Standard Stars'' (AJ, 133, 768 [2007])

    Science.gov (United States)

    Landolt, Arlo U.; Uomoto, Alan K.

    2007-05-01

    The authors thank John Marriner for calling their attention to an error in § 4 for the discussion of photometry relating to BD +26 2606 and BD +75 325. The error value used in the original calculation was the error for the star immediately below BD +26 2606 and BD +75 325 in Table 4. Those two paragraphs should read as follows: BD +26 2606.-This star has long been used as a primary spectrophotometric standard star (Oke & Gunn 1983). Carney & Latham (1987) showed that BD +26 2606 (G166-45) is a double-lined spectroscopic binary. It is also a high proper motion star (Perryman et al. 1997; see vol. 8 of the Hipparcos catalog). The Hipparcos catalog shows a range in brightness of 0.1 mag. The present data indicate that the error of a single observation is 0.0025×6=0.015 mag, marginally larger than one might expect for so bright a star. BD +75 325.-The star BD +75 325 was considered by Bartolini et al. (1982) to be a possible variable star of small amplitude, perhaps 0.03 mag. It has been assigned the suspected variable star name NSV 17739 (Kazarovets et al. 1998). Data taken on one night indicate the presence of a period of 0.0465116 days. However, small variations on other nights do not fit that period. The data in this paper were taken on 16 nights over a period of 63 months between 1985 December 14 and 1991 March 25. No more than two or three data points were taken on any one night. The mean error of a single observation is 0.011 mag, perhaps a bit too large for a star so bright, but certainly in disagreement with the short-term amplitude found by Bartolini et al. (1982). What is more interesting, however, is that Bartolini et al. quote a V magnitude of 8.9 (their Table 1), whereas the current data indicate V=9.548, in agreement with the Hipparcos value of V=9.55 (HIP 40047). On the other hand, if one reads off an average Δm of -0.06 from their Figure 4 and applies that quantity to a V of 9.60, taken from SIMBAD, for their primary comparison star BD +74 356, one

  13. LED灯具光辐射安全相关标准介绍%Standards about Optical Radiation Safety of LED Luminaires

    Institute of Scientific and Technical Information of China (English)

    吴晓晨; 蔡喆; 彭振坚

    2011-01-01

    This is a introduction of standard publications about optical radiation safety of LED luminaries,including ICNIRP optical radiation guidelines,IEC laser products safety,and the IEC,CIE,EU,ANSI/IESNA standards for photobiological safety of lamp and lamp systems.The difference and relations of these standards are analyzed.%介绍了关于LED光辐射安全的主要标准,包括国际非电离辐射防护委员会的光辐射导则、国际照明委员会、国际电工委员会、欧盟、北美的激光产品或灯和灯系统的光生物安全性标准,分析了这些标准的差异和联系。

  14. Phase-resolved functional optical coherence tomography: simultaneous imaging of in situ tissue structure, blood flow velocity, standard deviation, birefringence, and Stokes vectors in human skin

    Science.gov (United States)

    Ren, Hongwu; Ding, Zhihua; Zhao, Yonghua; Miao, Jianjun; Nelson, J. Stuart; Chen, Zhongping

    2002-10-01

    We describe a phase-resolved functional optical coherence tomography system that can simultaneously yield in situ images of tissue structure, blood flow velocity, standard deviation, birefringence, and the Stokes vectors in human skin. Multifunctional images were obtained by processing of analytical interference fringe signals derived from two perpendicular polarization-detection channels. The blood flow velocity and standard deviation images were obtained by comparison of the phases from pairs of analytical signals in neighboring A-lines in the same polarization state. The analytical signals from two polarization-diversity detection channels were used to determine the four Stokes vectors for four reference polarization states. From the four Stokes vectors, the birefringence image, which is not sensitive to the orientation of the optical axis in the sample, was obtained. Multifunctional in situ images of a port wine stain birthmark in human skin are presented.

  15. Contributed Review: Absolute spectral radiance calibration of fiber-optic shock-temperature pyrometers using a coiled-coil irradiance standard lamp

    Energy Technology Data Exchange (ETDEWEB)

    Fat’yanov, O. V., E-mail: fatyan1@gps.caltech.edu; Asimow, P. D., E-mail: asimow@gps.caltech.edu [Division of Geological and Planetary Sciences 252-21, California Institute of Technology, Pasadena, California 91125 (United States)

    2015-10-15

    We describe an accurate and precise calibration procedure for multichannel optical pyrometers such as the 6-channel, 3-ns temporal resolution instrument used in the Caltech experimental geophysics laboratory. We begin with a review of calibration sources for shock temperatures in the 3000-30 000 K range. High-power, coiled tungsten halogen standards of spectral irradiance appear to be the only practical alternative to NIST-traceable tungsten ribbon lamps, which are no longer available with large enough calibrated area. However, non-uniform radiance complicates the use of such coiled lamps for reliable and reproducible calibration of pyrometers that employ imaging or relay optics. Careful analysis of documented methods of shock pyrometer calibration to coiled irradiance standard lamps shows that only one technique, not directly applicable in our case, is free of major radiometric errors. We provide a detailed description of the modified Caltech pyrometer instrument and a procedure for its absolute spectral radiance calibration, accurate to ±5%. We employ a designated central area of a 0.7× demagnified image of a coiled-coil tungsten halogen lamp filament, cross-calibrated against a NIST-traceable tungsten ribbon lamp. We give the results of the cross-calibration along with descriptions of the optical arrangement, data acquisition, and processing. We describe a procedure to characterize the difference between the static and dynamic response of amplified photodetectors, allowing time-dependent photodiode correction factors for spectral radiance histories from shock experiments. We validate correct operation of the modified Caltech pyrometer with actual shock temperature experiments on single-crystal NaCl and MgO and obtain very good agreement with the literature data for these substances. We conclude with a summary of the most essential requirements for error-free calibration of a fiber-optic shock-temperature pyrometer using a high-power coiled tungsten halogen

  16. Dependence of loading time on control parameters in a standard vapour-loaded magneto-optical trap

    Institute of Scientific and Technical Information of China (English)

    Zhang Yi-Chi; Wu Ji-Zhou; Li Yu-Qing; Ma Jie; Wang Li-Rong; Zhao Yan-Ting; Xiao Lian-Tuan; Jia Suo-Tang

    2011-01-01

    Loading time is one of the most important dynamic characteristics of a magneto-optical trap.In this paper,we primarily report on a detailed experimental study of the effects of some magneto-optical trap control parameters on loading time,including the background vacuum pressure,the magnetic field gradient,and the intensities of trapping and repumping lasers.We compare the results with previous theoretical and experimental results,and give qualitative analysis.These experimental investigations offer some useful guidelines to control the loading time of magneto-optical traps.The controllable loading time achieved is helpful to enhance the signal-to-noise ratio of photoassociation spectroscopy,which is remarkably improved from 7 to 28.6.

  17. Research on the standards of indicators associated with maintain time in bidirectional beam tracking in inter-satellites optical communication links.

    Science.gov (United States)

    Yu, Siyuan; Wu, Feng; Tan, Liying; Guo, Pengzhen; Ma, Jing

    2015-10-19

    We report on a novel technology for high-speed inter-satellites optical communication by bidirectional beam tracking. By establishing the relation between the compensation effect and the parameters of response time and overshoot situation, the stability can be well compensated simply by the control system. Thus the relation between compensation effect and maintain time can be predicted from ground tests, and the certain evaluation standard could be established to meet the requirements of system. The other critical factors, such as signal-to-noise ratio and pointing angle error, have also been considered to improve the stability. The general approach can provide us a powerful path to overcome the performance limitation of bidirectional beam tracking, which can be expected to be widely applied in Free Space optics communications in future.

  18. Noise-immune complex correlation for vasculature imaging based on standard and Jones-matrix optical coherence tomography

    Science.gov (United States)

    Makita, Shuichi; Kurokawa, Kazuhiro; Hong, Young-Joo; Li, En; Miura, Masahiro; Yasuno, Yoshiaki

    2016-03-01

    A new optical coherence angiography (OCA) method, called correlation mapping OCA (cmOCA), is presented by using the SNR-corrected complex correlation. An SNR-correction theory for the complex correlation calculation is presented. The method also integrates a motion-artifact-removal method for the sample motion induced decorrelation artifact. The theory is further extended to compute more reliable correlation by using multi- channel OCT systems, such as Jones-matrix OCT. The high contrast vasculature imaging of in vivo human posterior eye has been obtained. Composite imaging of cmOCA and degree of polarization uniformity indicates abnormalities of vasculature and pigmented tissues simultaneously.

  19. A comparison of two 40Ca+ single-ion optical frequency standards at the 5 × 10-17 level and an evaluation of systematic shifts

    Science.gov (United States)

    Huang, Y.; Guan, H.; Bian, W.; Ma, L.; Liang, K.; Li, T.; Gao, K.

    2017-05-01

    A comparison of two optical frequency standards and a detailed study of the systematic frequency shifts of each 40Ca+ single-ion optical frequency standard is presented. The methods used for the systematic shift evaluation of the comparison measurements are also provided. One of the ion traps runs at a chosen operating frequency of 24.7 MHz, determined by the differential scalar polarizability of the clock transition, at which frequency the rf-induced Stark shifts and second-order Doppler shifts cancel each other, yielding a great suppression in the combined micromotion shifts. After compensating for the micromotion, the two optical frequency standards both reach an uncertainty level of a few parts in 10-17, which is more than an order of magnitude smaller compared to a few years ago. The dominant source of uncertainty is the blackbody radiation shift after minimizing the micromotion-induced shifts. The blackbody radiation shift is evaluated by controlling and measuring the temperature at the trap center. With a measurement over one month, the frequency difference between the two clocks is measured to be 3.2 × 10-17 with a measurement uncertainty of 5.5 × 10-17, considering both the statistical (1.9 × 10-17) and the systematic (5.1 × 10-17) uncertainties. Due to improvement of the clock laser and better control of the optical and electromagnetic field geometry and the laboratory conditions, a fractional stability of 7 × 10-17 in 20,000 s of averaging time is achieved. The absolute frequency of the 40Ca+ 4 s2S1/2-3d 2D5/2 clock transition is measured as 411 042 129 776 401.7 (1.1) Hz, with a fractional uncertainty of 2.7 × 10-15 using the GPS satellites as a link to the SI second. Details of the method used for the systematic shift evaluation of the measurements are given.

  20. Sloan Digital Sky Survey Standard Star Catalog for Stripe 82: The Dawn of Industrial 1% Optical Photometry

    Science.gov (United States)

    2007-09-01

    Thiswidespread use of the ugriz photometric system motivates the construction of a large standard star catalog with 1% accuracy. As part of its im- aging...6 Department of Astronomy, Graduate School of Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan. 7 Institute for Cosmic Ray...perpendicular to the blue part of the locus in the g r vs. u g plane; w, perpendicular to the blue part in the r i vs. g r plane; x, perpendicular to

  1. Standard-Fractionated Radiotherapy for Optic Nerve Sheath Meningioma: Visual Outcome Is Predicted by Mean Eye Dose

    Energy Technology Data Exchange (ETDEWEB)

    Abouaf, Lucie [Neuro-Ophthalmology Unit, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); Girard, Nicolas [Radiotherapy-Oncology Department, Lyon Sud Hospital, Hospices Civils de Lyon, Lyon (France); Claude Bernard University, Lyon (France); Lefort, Thibaud [Neuro-Radiology Department, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); D' hombres, Anne [Claude Bernard University, Lyon (France); Tilikete, Caroline; Vighetto, Alain [Neuro-Ophthalmology Unit, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); Claude Bernard University, Lyon (France); Mornex, Francoise, E-mail: francoise.mornex@chu-lyon.fr [Claude Bernard University, Lyon (France)

    2012-03-01

    Purpose: Radiotherapy has shown its efficacy in controlling optic nerve sheath meningiomas (ONSM) tumor growth while allowing visual acuity to improve or stabilize. However, radiation-induced toxicity may ultimately jeopardize the functional benefit. The purpose of this study was to identify predictive factors of poor visual outcome in patients receiving radiotherapy for ONSM. Methods and Materials: We conducted an extensive analysis of 10 patients with ONSM with regard to clinical, radiologic, and dosimetric aspects. All patients were treated with conformal radiotherapy and subsequently underwent biannual neuroophthalmologic and imaging assessments. Pretreatment and posttreatment values of visual acuity and visual field were compared with Wilcoxon's signed rank test. Results: Visual acuity values significantly improved after radiotherapy. After a median follow-up time of 51 months, 6 patients had improved visual acuity, 4 patients had improved visual field, 1 patient was in stable condition, and 1 patient had deteriorated visual acuity and visual field. Tumor control rate was 100% at magnetic resonance imaging assessment. Visual acuity deterioration after radiotherapy was related to radiation-induced retinopathy in 2 patients and radiation-induced mature cataract in 1 patient. Study of radiotherapy parameters showed that the mean eye dose was significantly higher in those 3 patients who had deteriorated vision. Conclusions: Our study confirms that radiotherapy is efficient in treating ONSM. Long-term visual outcome may be compromised by radiation-induced side effects. Mean eye dose has to be considered as a limiting constraint in treatment planning.

  2. The position of a standard optical computer mouse affects cardiorespiratory responses during the operation of a computer under time constraints

    Directory of Open Access Journals (Sweden)

    Shunji Sako

    2014-08-01

    Full Text Available Objectives: This study investigated the association between task-induced stress and fatigue by examining the cardiovascular responses of subjects using different mouse positions while operating a computer under time constraints. Material and Methods: The study was participated by 16 young, healthy men and examined the use of optical mouse devices affixed to laptop computers. Two mouse positions were investigated: (1 the distal position (DP, in which the subjects place their forearms on the desk accompanied by the abduction and flexion of their shoulder joints, and (2 the proximal position (PP, in which the subjects place only their wrists on the desk without using an armrest. The subjects continued each task for 16 min. We assessed differences in several characteristics according to mouse position, including expired gas values, autonomic nerve activities (based on cardiorespiratory responses, operating efficiencies (based on word counts, and fatigue levels (based on the visual analog scale – VAS. Results: Oxygen consumption (VO2, the ratio of inspiration time to respiration time (Ti/Ttotal, respiratory rate (RR, minute ventilation (VE, and the ratio of expiration to inspiration (Te/Ti were significantly lower when the participants were performing the task in the DP than those obtained in the PP. Tidal volume (VT, carbon dioxide output rates (VCO2/VE, and oxygen extraction fractions (VO2/VE were significantly higher for the DP than they were for the PP. No significant difference in VAS was observed between the positions; however, as the task progressed, autonomic nerve activities were lower and operating efficiencies were significantly higher for the DP than they were for the PP. Conclusions: Our results suggest that the DP has fewer effects on cardiorespiratory functions, causes lower levels of sympathetic nerve activity and mental stress, and produces a higher total workload than the PP. This suggests that the DP is preferable to the PP when

  3. Human photoreceptor cone density measured with adaptive optics technology (rtx1 device) in healthy eyes: Standardization of measurements.

    Science.gov (United States)

    Zaleska-Żmijewska, Anna; Wawrzyniak, Zbigniew M; Ulińska, Magdalena; Szaflik, Jerzy; Dąbrowska, Anna; Szaflik, Jacek P

    2017-06-01

    The anatomic structures of the anterior segment of the eye enable correct reception of stimuli by the retina, which contains receptors that receive light impulses and transmit them to the visual cortex. The aim of this study was to assess the effect of the size of the sampling window in an adaptive optics (AO) flood-illumination retinal camera (rtx1) on cone density measurements in the eyes of healthy individuals and to investigate the differences in cone density and spacing in different quadrants of the retina. Thirty-three subjects with no ophthalmic or systemic disease underwent a detailed ophthalmologic examination. Photographs of retinal fragments 3 degrees from the fovea were taken using the rtx1 AO retinal camera. We used sampling windows with 3 sizes (50 × 50, 100 × 100, and 250 × 250 μm). Cone density, spacing, and shape were determined using AOdetect software. The median (interquartile range) cone density was 19,269 (4964) cones/mm. There were statistically significant differences between measurements taken with the 50/50 and 250/250-m windows. There were no significant differences in the cone spacing results between any of the windows examined, but the measurements differed according to location between the superior and temporal quadrants. The most common cone shape was hexagonal (47.6%) for all window sizes and locations. These findings may help in the development of a normative database for variation in cone density in healthy subjects and to allow the best window to be chosen for obtain the most correct values for eccentricity measurements of 3 degrees. In our study, the optimal sampling window was 100 × 100 μm.

  4. Effect of temperature on structural, optical and photoluminescence studies on ZnO nanoparticles synthesized by the standard co-precipitation method

    Energy Technology Data Exchange (ETDEWEB)

    Raj, K. Pradeev [Research and Development Centre, Bharathiar University, Coimbatore 641046, Tamil Nadu (India); Department of Physics, CSI College of Engineering, Ooty 643215, Tamil Nadu (India); Sadayandi, K. [Department of Physics, Alagappa Government Arts College, Karaikudi, Sivagangai 630003, Tamil Nadu (India)

    2016-04-15

    This present study brings the synthesis of Zinc oxide (ZnO) nanoparticles (NPs) by the standard aqueous chemical route technique. The impact of calcination temperature on the extent of the ZnO nanoparticles is studied for its lattice constraints. X-ray diffraction (XRD) affirms the hexagonal Wurtzite structure of the synthesized ZnO nanoparticles. From the Williamson–Hall (W–H) plot, positive slope is inferred for pure and calcined ZnO NPs and confirms the presence of tensile strain. From the SEM images it is found that the crystallinity enhances with calcination temperature. From the optical studies, it is found that the band gap energy decreases with improved transmission. The Photoluminescence (PL) spectrum reveals the UV emission is strong near the band-edge. The emission peaks around 400–480 nm result in blue emission and the peaks around 540–560 nm result in green emission. Decrease in band gap energy and enhancement in PL studies reveal the red shift of the calcined ZnO exhibiting solid quantum confinements.

  5. The Global Network of Optical Magnetometers for Exotic physics (GNOME): A novel scheme to search for physics beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Pustelny, Szymon [Institute of Physics, Jagiellonian University, Krakow (Poland); Department of Physics, University of California at Berkeley, Berkeley, CA (United States); Jackson Kimball, Derek F. [Department of Physics, California State University, Hayward, CA (United States); Pankow, Chris [Center for Gravitation, Cosmology, and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI (United States); Ledbetter, Micah P. [Department of Physics, University of California at Berkeley, Berkeley, CA (United States); Wlodarczyk, Przemyslaw [Department of Electronics, AGH University of Science and Technology, Krakow (Poland); Wcislo, Piotr [Institute of Physics, Jagiellonian University, Krakow (Poland); Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Torun (Poland); Pospelov, Maxim [Department of Physics and Astronomy, University of Victoria, Victoria, BC (Canada); Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada); Smith, Joshua R.; Read, Jocelyn [Gravitational-Wave Physics and Astronomy Center, Department of Physics, California State University, Fullerton, CA (United States); Gawlik, Wojciech [Institute of Physics, Jagiellonian University, Krakow (Poland); Budker, Dmitry [Department of Physics, University of California at Berkeley, Berkeley, CA (United States); Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2013-09-15

    A novel experimental scheme enabling the investigation of transient exotic spin couplings is discussed. The scheme is based on synchronous measurements of optical-magnetometer signals from several devices operating in magnetically shielded environments in distant locations (>or similar 100 km). Although signatures of such exotic couplings may be present in the signal from a single magnetometer, it would be challenging to distinguish them from noise. By analyzing the correlation between signals from multiple, geographically separated magnetometers, it is not only possible to identify the exotic transient but also to investigate its nature. The ability of the network to probe presently unconstrained physics beyond the Standard Model is examined by considering the spin coupling to stable topological defects (e.g., domain walls) of axion-like fields. In the spirit of this research, a brief ({proportional_to}2 hours) demonstration experiment involving two magnetometers located in Krakow and Berkeley ({proportional_to}9000 km separation) is presented and discussion of the data-analysis approaches that may allow identification of transient signals is provided. The prospects of the network are outlined in the last part of the paper. (copyright 2013 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Multivendor Spectral-Domain Optical Coherence Tomography Dataset, Observer Annotation Performance Evaluation, and Standardized Evaluation Framework for Intraretinal Cystoid Fluid Segmentation

    Directory of Open Access Journals (Sweden)

    Jing Wu

    2016-01-01

    Full Text Available Development of image analysis and machine learning methods for segmentation of clinically significant pathology in retinal spectral-domain optical coherence tomography (SD-OCT, used in disease detection and prediction, is limited due to the availability of expertly annotated reference data. Retinal segmentation methods use datasets that either are not publicly available, come from only one device, or use different evaluation methodologies making them difficult to compare. Thus we present and evaluate a multiple expert annotated reference dataset for the problem of intraretinal cystoid fluid (IRF segmentation, a key indicator in exudative macular disease. In addition, a standardized framework for segmentation accuracy evaluation, applicable to other pathological structures, is presented. Integral to this work is the dataset used which must be fit for purpose for IRF segmentation algorithm training and testing. We describe here a multivendor dataset comprised of 30 scans. Each OCT scan for system training has been annotated by multiple graders using a proprietary system. Evaluation of the intergrader annotations shows a good correlation, thus making the reproducibly annotated scans suitable for the training and validation of image processing and machine learning based segmentation methods. The dataset will be made publicly available in the form of a segmentation Grand Challenge.

  7. Structure-Function Modeling of Optical Coherence Tomography and Standard Automated Perimetry in the Retina of Patients with Autosomal Dominant Retinitis Pigmentosa.

    Directory of Open Access Journals (Sweden)

    Travis B Smith

    Full Text Available To assess relationships between structural and functional biomarkers, including new topographic measures of visual field sensitivity, in patients with autosomal dominant retinitis pigmentosa.Spectral domain optical coherence tomography line scans and hill of vision (HOV sensitivity surfaces from full-field standard automated perimetry were semi-automatically aligned for 60 eyes of 35 patients. Structural biomarkers were extracted from outer retina b-scans along horizontal and vertical midlines. Functional biomarkers were extracted from local sensitivity profiles along the b-scans and from the full visual field. These included topographic measures of functional transition such as the contour of most rapid sensitivity decline around the HOV, herein called HOV slope for convenience. Biomarker relationships were assessed pairwise by coefficients of determination (R2 from mixed-effects analysis with automatic model selection.Structure-function relationships were accurately modeled (conditional R(2>0.8 in most cases. The best-fit relationship models and correlation patterns for horizontally oriented biomarkers were different than vertically oriented ones. The structural biomarker with the largest number of significant functional correlates was the ellipsoid zone (EZ width, followed by the total photoreceptor layer thickness. The strongest correlation observed was between EZ width and HOV slope distance (marginal R(2 = 0.85, p<10(-10. The mean sensitivity defect at the EZ edge was 7.6 dB. Among all functional biomarkers, the HOV slope mean value, HOV slope mean distance, and maximum sensitivity along the b-scan had the largest number of significant structural correlates.Topographic slope metrics show promise as functional biomarkers relevant to the transition zone. EZ width is strongly associated with the location of most rapid HOV decline.

  8. Optical Spectroscopy

    DEFF Research Database (Denmark)

    Thyrhaug, Erling

    The work presented in this thesis is broadly concerned with how complexation reactions and molecular motion can be characterized with the standard techniques in optical spectroscopy. The thesis aims to show a relatively broad range of methods for probing physico-chemical properties in fluorophore...... containing systems and are characterized using techniques in optical spectroscopy. Of the standard techniques in optical spectroscopy, particular attention has been paid to those based on time-resolved measurements and polarization, which is reflected in the experiment design in the projects. Not all...... reactions by optical spectroscopy. In project 1 simple steady-state absorption and fluorescence spectroscopy is used to determine the stoichiometries and equilibrium constants in the inclusion complex formation between cyclodextrins and derivatives of the water-insoluble oligo(phenylene vinylene) in aqueous...

  9. 155 Mb/s-10 Gb/s combined FSK-IM/optical label-packet modulation signals 100 km transmission over standard single mode fiber using mid-span spectral inversion by four-wave mixing in an SOA

    Institute of Scientific and Technical Information of China (English)

    Xin Xiang-Jun; Ma Jian-Xin; Zhang Qi; Deng Chao-Gong; Wang Kui-Ru; Yu Chong-Xiu; Liu Bo

    2009-01-01

    This paper introduces the mid-span spectral inversion by four-wave mixing in a commercially available semiconductor optical amplifier (SOA) with a length of about 1.5 mm to optical label switching network based on combined frequency shift keying (FSK)-intensiy modulation (IM)/optical label-packet modulation to overcome the dispersion limitation of fiber.The 155 Mb/s-10 Gb/s combined FSK/IM signal is experimentally transmitted over a 100 km standard single mode fiber.10-10 and 10-9 BER (bit error ratio),or even better,is achieved for the FSK label and IM packet,respectively.The -19 dB power conversion efficiency is obtained for -1 nm wavelength detuning.

  10. Low-power colorless all-optical 2R regeneration of 25 Gb/s NRZ signals using a standard DFB laser

    DEFF Research Database (Denmark)

    Huybrechts, Koen; Peucheret, Christophe; Seoane, Jorge

    2010-01-01

    We demonstrate the first all-optical 2R regeneration of 25 Gbit/s NRZ data based on hysteresis in a DFB laser. The scheme results in BER improvement, exhibits low power consumption and is effective after fiber transmission.......We demonstrate the first all-optical 2R regeneration of 25 Gbit/s NRZ data based on hysteresis in a DFB laser. The scheme results in BER improvement, exhibits low power consumption and is effective after fiber transmission....

  11. Optics/Optical Diagnostics Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Optics/Optical Diagnostics Laboratory supports graduate instruction in optics, optical and laser diagnostics and electro-optics. The optics laboratory provides...

  12. All-optical repeater.

    Science.gov (United States)

    Silberberg, Y

    1986-06-01

    An all-optical device containing saturable gain, saturable loss, and unsaturable loss is shown to transform weak, distorted optical pulses into uniform standard-shape pulses. The proposed device performs thresholding, amplification, and pulse shaping as required from an optical repeater. It is shown that such a device could be realized by existing semiconductor technology.

  13. Fiscal 1997 report on the results of the international standardization R and D. Standardization of the optical evaluation method of the performance of shape stability of the apparel; 1997 nendo seika hokokusho kokusai hyojun soseigata kenkyu kaihatsu. Apareru seihin no keitai antei seino no kogakuteki hyoka hoho no hyojunka

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    For the purpose of proposing the optical evaluation method of appearance of the apparel as an international standard, studies were made of the following: 3D determination/assessment method, development of mannequin holders, development of shape-retentive cubic replicas, washing/drying conditions, etc. As to the shape retention, cubic replicas for collars and cuffs were manufactured and inputted as image data. Besides, as to the evaluation items such as wrinkles, seam-puckering and pleats, the class determining algorithm was made by comparison between the measuring data and the results of the human-sight measurement. These were embodied into mannequin holders and integrated into the optical 3D instrumental system, which was discussed as a 3D determination/assessment system. By the development of the 3D measuring system and image analysis program, a comprehensive evaluation system was developed which can determine/assess the performance of shape stability of the apparel optically as absolute evaluation. This method will be internationally proposed as an optical evaluation method of the appearance of the apparel. 86 figs., 8 tabs.

  14. Theoretical Design of a Depolarized Interferometric Fiber-Optic Gyroscope (IFOG) on SMF-28 Single-Mode Standard Optical Fiber Based on Closed-Loop Sinusoidal Phase Modulation with Serrodyne Feedback Phase Modulation Using Simulation Tools for Tactical and Industrial Grade Applications.

    Science.gov (United States)

    Pérez, Ramón José; Álvarez, Ignacio; Enguita, José María

    2016-04-27

    This article presents, by means of computational simulation tools, a full analysis and design of an Interferometric Fiber-Optic Gyroscope (IFOG) prototype based on a closed-loop configuration with sinusoidal bias phase- modulation. The complete design of the different blocks, optical and electronic, is presented, including some novelties as the sinusoidal bias phase-modulation and the use of an integrator to generate the serrodyne phase-modulation signal. The paper includes detailed calculation of most parameter values, and the plots of the resulting signals obtained from simulation tools. The design is focused in the use of a standard single-mode optical fiber, allowing a cost competitive implementation compared to commercial IFOG, at the expense of reduced sensitivity. The design contains an IFOG model that accomplishes tactical and industrial grade applications (sensitivity ≤ 0.055 °/h). This design presents two important properties: (1) an optical subsystem with advanced conception: depolarization of the optical wave by means of Lyot depolarizers, which allows to use a sensing coil made by standard optical fiber, instead by polarization maintaining fiber, which supposes consequent cost savings and (2) a novel and simple electronic design that incorporates a linear analog integrator with reset in feedback chain, this integrator generating a serrodyne voltage-wave to apply to Phase-Modulator (PM), so that it will be obtained the interferometric phase cancellation. This particular feedback design with sawtooth-wave generated signal for a closed-loop configuration with sinusoidal bias phase modulation has not been reported till now in the scientific literature and supposes a considerable simplification with regard to previous designs based on similar configurations. The sensing coil consists of an 8 cm average diameter spool that contains 300 m of standard single-mode optical-fiber (SMF-28 type) realized by quadrupolar winding. The working wavelength will be

  15. Theoretical Design of a Depolarized Interferometric Fiber-Optic Gyroscope (IFOG) on SMF-28 Single-Mode Standard Optical Fiber Based on Closed-Loop Sinusoidal Phase Modulation with Serrodyne Feedback Phase Modulation Using Simulation Tools for Tactical and Industrial Grade Applications

    Science.gov (United States)

    Pérez, Ramón José; Álvarez, Ignacio; Enguita, José María

    2016-01-01

    This article presents, by means of computational simulation tools, a full analysis and design of an Interferometric Fiber-Optic Gyroscope (IFOG) prototype based on a closed-loop configuration with sinusoidal bias phase- modulation. The complete design of the different blocks, optical and electronic, is presented, including some novelties as the sinusoidal bias phase-modulation and the use of an integrator to generate the serrodyne phase-modulation signal. The paper includes detailed calculation of most parameter values, and the plots of the resulting signals obtained from simulation tools. The design is focused in the use of a standard single-mode optical fiber, allowing a cost competitive implementation compared to commercial IFOG, at the expense of reduced sensitivity. The design contains an IFOG model that accomplishes tactical and industrial grade applications (sensitivity ≤ 0.055 °/h). This design presents two important properties: (1) an optical subsystem with advanced conception: depolarization of the optical wave by means of Lyot depolarizers, which allows to use a sensing coil made by standard optical fiber, instead by polarization maintaining fiber, which supposes consequent cost savings and (2) a novel and simple electronic design that incorporates a linear analog integrator with reset in feedback chain, this integrator generating a serrodyne voltage-wave to apply to Phase-Modulator (PM), so that it will be obtained the interferometric phase cancellation. This particular feedback design with sawtooth-wave generated signal for a closed-loop configuration with sinusoidal bias phase modulation has not been reported till now in the scientific literature and supposes a considerable simplification with regard to previous designs based on similar configurations. The sensing coil consists of an 8 cm average diameter spool that contains 300 m of standard single-mode optical-fiber (SMF-28 type) realized by quadrupolar winding. The working wavelength will be

  16. Theoretical Design of a Depolarized Interferometric Fiber-Optic Gyroscope (IFOG on SMF-28 Single-Mode Standard Optical Fiber Based on Closed-Loop Sinusoidal Phase Modulation with Serrodyne Feedback Phase Modulation Using Simulation Tools for Tactical and Industrial Grade Applications

    Directory of Open Access Journals (Sweden)

    Ramón José Pérez

    2016-04-01

    Full Text Available This article presents, by means of computational simulation tools, a full analysis and design of an Interferometric Fiber-Optic Gyroscope (IFOG prototype based on a closed-loop configuration with sinusoidal bias phase- modulation. The complete design of the different blocks, optical and electronic, is presented, including some novelties as the sinusoidal bias phase-modulation and the use of an integrator to generate the serrodyne phase-modulation signal. The paper includes detailed calculation of most parameter values, and the plots of the resulting signals obtained from simulation tools. The design is focused in the use of a standard single-mode optical fiber, allowing a cost competitive implementation compared to commercial IFOG, at the expense of reduced sensitivity. The design contains an IFOG model that accomplishes tactical and industrial grade applications (sensitivity ≤ 0.055 °/h. This design presents two important properties: (1 an optical subsystem with advanced conception: depolarization of the optical wave by means of Lyot depolarizers, which allows to use a sensing coil made by standard optical fiber, instead by polarization maintaining fiber, which supposes consequent cost savings and (2 a novel and simple electronic design that incorporates a linear analog integrator with reset in feedback chain, this integrator generating a serrodyne voltage-wave to apply to Phase-Modulator (PM, so that it will be obtained the interferometric phase cancellation. This particular feedback design with sawtooth-wave generated signal for a closed-loop configuration with sinusoidal bias phase modulation has not been reported till now in the scientific literature and supposes a considerable simplification with regard to previous designs based on similar configurations. The sensing coil consists of an 8 cm average diameter spool that contains 300 m of standard single-mode optical-fiber (SMF-28 type realized by quadrupolar winding. The working

  17. Standard Test Method for Size-Differentiated Counting of Particles and Fibers Released from Cleanroom Wipers Using Optical and Scanning Electron Microscopy

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This test method covers testing all wipers used in cleanrooms and other controlled environments for characteristics related to particulate cleanliness. 1.2 This test method includes the use of computer-based image analysis and counting hardware and software for the counting of densely particle-laden filters (see ). While the use of this equipment is not absolutely necessary, it is strongly recommended to enhance the accuracy, speed, and consistency of counting. 1.3 The values stated in SI units are to be regarded as the standard. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  18. Frequency Standards and Metrology

    Science.gov (United States)

    Maleki, Lute

    2009-04-01

    Preface / Lute Maleki -- Symposium history / Jacques Vanier -- Symposium photos -- pt. I. Fundamental physics. Variation of fundamental constants from the big bang to atomic clocks: theory and observations (Invited) / V. V. Flambaum and J. C. Berengut. Alpha-dot or not: comparison of two single atom optical clocks (Invited) / T. Rosenband ... [et al.]. Variation of the fine-structure constant and laser cooling of atomic dysprosium (Invited) / N. A. Leefer ... [et al.]. Measurement of short range forces using cold atoms (Invited) / F. Pereira Dos Santos ... [et al.]. Atom interferometry experiments in fundamental physics (Invited) / S. W. Chiow ... [et al.]. Space science applications of frequency standards and metrology (Invited) / M. Tinto -- pt. II. Frequency & metrology. Quantum metrology with lattice-confined ultracold Sr atoms (Invited) / A. D. Ludlow ... [et al.]. LNE-SYRTE clock ensemble: new [symbol]Rb hyperfine frequency measurement - spectroscopy of [symbol]Hg optical clock transition (Invited) / M. Petersen ... [et al.]. Precise measurements of S-wave scattering phase shifts with a juggling atomic clock (Invited) / S. Gensemer ... [et al.]. Absolute frequency measurement of the [symbol] clock transition (Invited) / M. Chwalla ... [et al.]. The semiclassical stochastic-field/atom interaction problem (Invited) / J. Camparo. Phase and frequency noise metrology (Invited) / E. Rubiola ... [et al.]. Optical spectroscopy of atomic hydrogen for an improved determination of the Rydberg constant / J. L. Flowers ... [et al.] -- pt. III. Clock applications in space. Recent progress on the ACES mission (Invited) / L. Cacciapuoti and C. Salomon. The SAGAS mission (Invited) / P. Wolf. Small mercury microwave ion clock for navigation and radioScience (Invited) / J. D. Prestage ... [et al.]. Astro-comb: revolutionizing precision spectroscopy in astrophysics (Invited) / C. E. Kramer ... [et al.]. High frequency very long baseline interferometry: frequency standards and

  19. Digital Standard Star Tracker

    Science.gov (United States)

    McQuerry, J. P., Jr.

    The Digital Standard Star Tracker (DSST) is an electro-optical instrument which provides position data used for precise attitude determination. The new DSST design uses flight-proven optical and sensor components from the BASD/NASA Standard Star Tracker (SST) programs while incorporating digital electronics techniques to improve producibility and reliability. This design approach has resulted in a new instrument capable of less than 10 arc second calibrated accuracy with 50 percent of the electrical components and only 10 percent of the electrical assemblies used in the SST.

  20. IEEE 1393 Spaceborne Fiber Optic Data Bus: A Standard Approach to On-Board Payload Data Handling Networks for the AIAA Space Technology Conference and Exposition "Partnering in the 21th Century"

    Science.gov (United States)

    Andrucyk, Dennis J.; Orlando, Fred J.; Chalfant, Charles H.

    1999-01-01

    The Spaceborne Fiber Optic Data Bus (SFODB) is the next generation in on-board data handling networks. It will do for high speed payloads what SAE 1773 has done for on-board command and telemetry systems. That is, it will significantly reduce the cost of payload development, integration and test through interface standardization. As defined in IEEE 1393, SFODB is a 1 Gb/s, fiber optic network specifically designed to support the real-time, on-board data handling requirements of remote sensing spacecraft. The network is highly reliable, fault tolerant, and capable of withstanding the rigors of launch and the harsh space environment. SFODB achieves this operational and environmental performance while maintaining the small size, light weight, and low power necessary for spaceborne applications. SFODB was developed jointly by DoD and NASA GSFC to meet the on-board data handling needs of Remote Sensing satellites. This jointly funded project produced a complete set of flight transmitters, receivers and protocol ASICS; a complete Development & Evaluation System; and, the IEEE 1393 standard.

  1. Optic glioma

    Science.gov (United States)

    Glioma - optic; Optic nerve glioma; Juvenile pilocytic astrocytoma; Brain cancer - optic glioma ... Optic gliomas are rare. The cause of optic gliomas is unknown. Most optic gliomas are slow-growing ...

  2. Hardware implementation of converting ternary optical computer MSD into standard binary data%三值光学计算机MSD转换为标准二进制数的硬件实现

    Institute of Scientific and Technical Information of China (English)

    江家宝; 陈迅雷; 欧阳山

    2016-01-01

    In order to improve the storage and conversion efficiency of ternary optical computers , a serial and parallel hybrid method is presented for converting N bits modified signed digit (MSD) into N bits standard binary data .The logic structure of a hardware converter is designed using polarizers , liquid crystals ,optical splitters , mirrors, decoders and photoelectric tubes and so on based on the conversion method proposed here .The result can be output in standard binary data using a converter SD11a,nd the storage efficiency is improved by 50%,and the hardware implementation of MSD trans -formation is realized .%为了提高三值光学计算机的存储与转换效率,该文提出1种把N位改进的有符号数(MSD)转换成N位标准二进制数的串并混合转换方法。基于此转换方法利用偏振片、液晶、分光器、反射镜、译码器和光电管等光电器件设计了硬件转换器逻辑结构。使用转换器SD11可以直接以标准二进制形式输出结果,从而使存储效率提高50%,同时实现MSD数据转换硬件化。

  3. ['Gold standard', not 'golden standard'

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2005-01-01

    In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same w

  4. ['Gold standard', not 'golden standard'

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2005-01-01

    In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same

  5. Internal standardization for the determination of cadmium, cobalt, chromium and manganese in saline produced water from petroleum industry by inductively coupled plasma optical emission spectrometry after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Bezerra, Marcos [Departamento de Geoquimica, Universidade Federal Fluminense, Outeiro Sao Joao Batista s/n, Centro, Niteroi/RJ, 24020-150 (Brazil); Universidade Estadual do Sudoeste da Bahia, Departamento de Quimica e Exatas, Rua Jose Moreira Sobrinho s/n, Jequiezinho, Jequie/BA, 45206-190 (Brazil)], E-mail: mbezerra@uesb.br; Mitihiro do Nascimento Maeda, Sergio; Padua Oliveira, Eliane [Departamento de Geoquimica, Universidade Federal Fluminense, Outeiro Sao Joao Batista s/n, Centro, Niteroi/RJ, 24020-150 (Brazil); Fatima Batista de Carvalho, Maria de [Centro de Pesquisas e Desenvolvimento da PETROBRAS, Avaliacao e Monitoramento Ambiental, Av. Jequitiba, 950, Cidade Universitaria, Rio de Janeiro/RJ, 21941-598 (Brazil); Erthal Santelli, Ricardo [Departamento de Geoquimica, Universidade Federal Fluminense, Outeiro Sao Joao Batista s/n, Centro, Niteroi/RJ, 24020-150 (Brazil)

    2007-09-15

    In the present paper a procedure is proposed for the determination of traces of Cd, Co, Mn and Cr in petroleum industry produced water by inductively coupled plasma optical emission spectrometry. The procedure is based on cloud point extraction of these metals, as their dithizonate complexes, into the surfactant-rich phase of octylphenoxypolyethoxyethanol surfactant (Triton X-114). Extractions were carried out in solutions with salinities between 10 per mille and 70 per mille. Since residual salinity in the surfactant-rich phase caused differences in its transport to the plasma, yttrium was used as an internal standard to correct for this effect. The simultaneous metal extraction procedure was optimized by response surface methodology using a Doehlert design and desirability function. Enhancement factors of 21, 21, 9 and 19, along with limits of quantification of 0.093, 0.20, 0.73 and 1.2 {mu}g L{sup -1}, and precision expressed as relative standard deviation (n = 8, 20.0 {mu}g L{sup -1}) of 5.8, 1.2, 1.7 and 5.7% were obtained for Cd, Co, Mn and Cr, respectively. The accuracy was evaluated by spike recovery tests on the high salinity water samples with salinity of 40 and 63 per mille.

  6. Internal standardization for the determination of cadmium, cobalt, chromium and manganese in saline produced water from petroleum industry by inductively coupled plasma optical emission spectrometry after cloud point extraction

    Science.gov (United States)

    Bezerra, Marcos Almeida; Mitihiro do Nascimento Maêda, Sérgio; Oliveira, Eliane Padua; de Fátima Batista de Carvalho, Maria; Santelli, Ricardo Erthal

    2007-09-01

    In the present paper a procedure is proposed for the determination of traces of Cd, Co, Mn and Cr in petroleum industry produced water by inductively coupled plasma optical emission spectrometry. The procedure is based on cloud point extraction of these metals, as their dithizonate complexes, into the surfactant-rich phase of octylphenoxypolyethoxyethanol surfactant (Triton X-114). Extractions were carried out in solutions with salinities between 10‰ and 70‰. Since residual salinity in the surfactant-rich phase caused differences in its transport to the plasma, yttrium was used as an internal standard to correct for this effect. The simultaneous metal extraction procedure was optimized by response surface methodology using a Doehlert design and desirability function. Enhancement factors of 21, 21, 9 and 19, along with limits of quantification of 0.093, 0.20, 0.73 and 1.2 μg L - 1 , and precision expressed as relative standard deviation ( n = 8, 20.0 μg L - 1 ) of 5.8, 1.2, 1.7 and 5.7% were obtained for Cd, Co, Mn and Cr, respectively. The accuracy was evaluated by spike recovery tests on the high salinity water samples with salinity of 40 and 63‰.

  7. Accounting standards

    NARCIS (Netherlands)

    Stellinga, B.; Mügge, D.

    2014-01-01

    The European and global regulation of accounting standards have witnessed remarkable changes over the past twenty years. In the early 1990s, EU accounting practices were fragmented along national lines and US accounting standards were the de facto global standards. Since 2005, all EU listed companie

  8. Wavefront coding with adaptive optics

    Science.gov (United States)

    Agbana, Temitope E.; Soloviev, Oleg; Bezzubik, Vitalii; Patlan, Vsevolod; Verhaegen, Michel; Vdovin, Gleb

    2015-03-01

    We have implemented an extended depth of field optical system by wavefront coding with a micromachined membrane deformable mirror. This approach provides a versatile extension to standard wavefront coding based on fixed phase mask. First experimental results validate the feasibility of the use of adaptive optics for variable depth wavefront coding in imaging optical systems.

  9. Computational toolbox for optical tweezers in geometrical optics

    CERN Document Server

    Callegari, Agnese; Gököz, A Burak; Volpe, Giovanni

    2014-01-01

    Optical tweezers have found widespread application in many fields, from physics to biology. Here, we explain in detail how optical forces and torques can be described within the geometrical optics approximation and we show that this approximation provides reliable results in agreement with experiments for particles whose characteristic dimensions are larger than the wavelength of the trapping light. Furthermore, we provide an object-oriented software package implemented in MatLab for the calculation of optical forces and torques in the geometrical optics regime: \\texttt{OTGO - Optical Tweezers in Geometrical Optics}. We provide all source codes for \\texttt{OTGO} as well as the documentation and code examples -- e.g., standard optical tweezers, optical tweezers with elongated particle, windmill effect, Kramers transitions between two optical traps -- necessary to enable users to effectively employ it in their research and teaching.

  10. Elementary wave optics

    CERN Document Server

    Webb, Robert H

    2005-01-01

    This undergraduate textbook presents thorough coverage of the standard topics of classical optics and optical instrument design; it also offers significant details regarding the concepts of modern optics. Its survey of the mathematical tools of optics grants students insights into the physical principles of quantum mechanics.Two principal concepts occur throughout: a treatment of scattering from real scatterers (leading to Huygens' principles, diffraction theory, the index of refraction, and related topics); and the difference between coherent and noncoherent wave phenomena. Examinations of su

  11. Communications standards

    CERN Document Server

    Stokes, A V

    1986-01-01

    Communications Standards deals with the standardization of computer communication networks. This book examines the types of local area networks (LANs) that have been developed and looks at some of the relevant protocols in more detail. The work of Project 802 is briefly discussed, along with a protocol which has developed from one of the LAN standards and is now a de facto standard in one particular area, namely the Manufacturing Automation Protocol (MAP). Factors that affect the usage of networks, such as network management and security, are also considered. This book is divided into three se

  12. Achieving Standardization

    DEFF Research Database (Denmark)

    Henningsson, Stefan

    2014-01-01

    competitive, national customs and regional economic organizations are seeking to establish a standardized solution for digital reporting of customs data. However, standardization has proven hard to achieve in the socio-technical e-Customs solution. In this chapter, the authors identify and describe what has...

  13. Achieving Standardization

    DEFF Research Database (Denmark)

    Henningsson, Stefan

    2016-01-01

    competitive, national customs and regional economic organizations are seeking to establish a standardized solution for digital reporting of customs data. However, standardization has proven hard to achieve in the socio-technical e-Customs solution. In this chapter, the authors identify and describe what has...

  14. (Terminology standardization)

    Energy Technology Data Exchange (ETDEWEB)

    Strehlow, R.A.

    1990-10-19

    Terminological requirements in information management was but one of the principal themes of the 2nd Congress on Terminology and Knowledge Engineering. The traveler represented the American Society for Testing and Materials' Committee on Terminology, of which he is the Chair. The traveler's invited workshop emphasized terminology standardization requirements in databases of material properties as well as practical terminology standardizing methods. The congress included six workshops in addition to approximately 82 lectures and papers from terminologists, artificial intelligence practitioners, and subject specialists from 18 countries. There were approximately 292 registrants from 33 countries who participated in the congress. The congress topics were broad. Examples were the increasing use of International Standards Organization (ISO) Standards in legislated systems such as the USSR Automated Data Bank of Standardized Terminology, the enhanced Physics Training Program based on terminology standardization in Physics in the Chinese province of Inner Mongolia, and the technical concept dictionary being developed at the Japan Electronic Dictionary Research Institute, which is considered to be the key to advanced artificial intelligence applications. The more usual roles of terminology work in the areas of machine translation. indexing protocols, knowledge theory, and data transfer in several subject specialties were also addressed, along with numerous special language terminology areas.

  15. Optical processing

    Science.gov (United States)

    Gustafson, S. C.

    1985-12-01

    The technical contributions were as follows: (1) Optical parallel 2-D neighborhood processor and optical processor assessment technique; (2) High accuracy with moderately accurate components and optical fredkin gate architectures; (3) Integrated optical threshold computing, pipelined polynomial processor, and all optical analog/digital converter; (4) Adaptive optical associative memory model with attention; (5) Effectiveness of parallelism and connectivity in optical computers; (6) Optical systolic array processing using an integrated acoustooptic module; (7) Optical threshold elements and networks, holographic threshold processors, adaptive matched spatial filtering, and coherence theory in optical computing; (8) Time-varying optical processing for sub-pixel targets, optical Kalman filtering, and adaptive matched filtering; (9) Optical degrees of freedom, ultra short optical pulses, number representations, content-addressable-memory processors, and integrated optical Givens rotation devices; (10) Optical J-K flip flop analysis and interfacing for optical computers; (11) Matrix multiplication algorithms and limits of incoherent optical computers; (12) Architecture for machine vision with sensor fusion, pattern recognition functions, and neural net implementations; (13) Optical computing algorithms, architectures, and components; and (14) Dynamic optical interconnections, advantages and architectures.

  16. Frequency standards

    CERN Document Server

    Riehle, Fritz

    2006-01-01

    Of all measurement units, frequency is the one that may be determined with the highest degree of accuracy. It equally allows precise measurements of other physical and technical quantities, whenever they can be measured in terms of frequency.This volume covers the central methods and techniques relevant for frequency standards developed in physics, electronics, quantum electronics, and statistics. After a review of the basic principles, the book looks at the realisation of commonly used components. It then continues with the description and characterisation of important frequency standards

  17. Optical atomic clocks

    CERN Document Server

    Poli, N; Gill, P; Tino, G M

    2014-01-01

    In the last ten years extraordinary results in time and frequency metrology have been demonstrated. Frequency-stabilization techniques for continuous-wave lasers and femto-second optical frequency combs have enabled a rapid development of frequency standards based on optical transitions in ultra-cold neutral atoms and trapped ions. As a result, today's best performing atomic clocks tick at an optical rate and allow scientists to perform high-resolution measurements with a precision approaching a few parts in $10^{18}$. This paper reviews the history and the state of the art in optical-clock research and addresses the implementation of optical clocks in a possible future redefinition of the SI second as well as in tests of fundamental physics.

  18. Modern optics

    CERN Document Server

    Guenther, B D

    2015-01-01

    Modern Optics is a fundamental study of the principles of optics using a rigorous physical approach based on Maxwell's Equations. The treatment provides the mathematical foundations needed to understand a number of applications such as laser optics, fiber optics and medical imaging covered in an engineering curriculum as well as the traditional topics covered in a physics based course in optics. In addition to treating the fundamentals in optical science, the student is given an exposure to actual optics engineering problems such as paraxial matrix optics, aberrations with experimental examples, Fourier transform optics (Fresnel-Kirchhoff formulation), Gaussian waves, thin films, photonic crystals, surface plasmons, and fiber optics. Through its many pictures, figures, and diagrams, the text provides a good physical insight into the topics covered. The course content can be modified to reflect the interests of the instructor as well as the student, through the selection of optional material provided in append...

  19. Optic Neuritis

    OpenAIRE

    1989-01-01

    Demyelinating optic neuritis is the most common cause of unilateral painful visual loss in the United States. Although patients presenting with demyelinating optic neuritis have favorable long-term visual prognosis, optic neuritis is the initial clinical manifestation of multiple sclerosis in 20% of patients. The Optic Neuritis Treatment Trial (ONTT) has helped stratify the risk of developing multiple sclerosis after the first episode of optic neuritis based on abnormal findings on brain MRI....

  20. Coupled-resonator optical waveguides

    DEFF Research Database (Denmark)

    Raza, Søren; Grgic, Jure; Pedersen, Jesper Goor

    2010-01-01

    Coupled-resonator optical waveguides hold potential for slow-light propagation of optical pulses. The dispersion properties may adequately be analyzed within the framework of coupled-mode theory. We extend the standard coupled-mode theory for such structures to also include complex-valued paramet...

  1. Standard deviations

    CERN Document Server

    Smith, Gary

    2015-01-01

    Did you know that having a messy room will make you racist? Or that human beings possess the ability to postpone death until after important ceremonial occasions? Or that people live three to five years longer if they have positive initials, like ACE? All of these ‘facts' have been argued with a straight face by researchers and backed up with reams of data and convincing statistics.As Nobel Prize-winning economist Ronald Coase once cynically observed, ‘If you torture data long enough, it will confess.' Lying with statistics is a time-honoured con. In Standard Deviations, ec

  2. EDITORIAL: Optical orientation Optical orientation

    Science.gov (United States)

    SAME ADDRESS *, Yuri; Landwehr, Gottfried

    2008-11-01

    radiation. The major results of the systematic work on optical orientation, both experimental and theoretical, at the Ioffe Institute and the Ecole Normale Supérieure in Paris are documented in the book Optical Orientation, edited by F Meier and B P Zakharchenya in the series Modern Problems in Condensed Matter Sciences [4], in which the foundations of optical orientation are comprehensively presented by renowned authors. This book is still the unsurpassed standard work in the field. If one asks what has become new since that publication in 1984 it is obviously the arrival of low-dimensional structures, two-dimensional heterostructures and zero-dimensional quantum dots. It has turned out that the quantum confinement can significantly modify the spin lifetime and the spin relaxation. The experimental work on spin alignment was done by a relative small number of researchers. However, the situation has substantially changed during the last decade. Research on spin-related phenomena has become very popular and the word 'spintronics' was coined. Spin research is no longer considered to be somewhat esoteric, since the replacement of silicon microelectronics based on the electron charge by spin-based electronics is being discussed. Whether these proposals can be realized remains to be seen. But one consequence has been a worldwide increase of high level basic research in spin phenomena. Another line of current research which has contributed to the popularity of spin-related research is quantum computing, based on spin-qubits. To be useful, solid state systems require long spin relaxation times and weak interaction with the environment. This is indispensable for low error rates. The difficulties in achieving these goals have been extensively discussed in the literature. Nowadays, because of the volume and diversity of spin-related work worldwide, a book on optical orientation like that edited by Meyer and Zakharchenya does not seem possible, so in this special issue of

  3. Engineering Optics

    CERN Document Server

    Iizuka, Keigo

    2008-01-01

    Engineering Optics is a book for students who want to apply their knowledge of optics to engineering problems, as well as for engineering students who want to acquire the basic principles of optics. It covers such important topics as optical signal processing, holography, tomography, holographic radars, fiber optical communication, electro- and acousto-optic devices, and integrated optics (including optical bistability). As a basis for understanding these topics, the first few chapters give easy-to-follow explanations of diffraction theory, Fourier transforms, and geometrical optics. Practical examples, such as the video disk, the Fresnel zone plate, and many more, appear throughout the text, together with numerous solved exercises. There is an entirely new section in this updated edition on 3-D imaging.

  4. Electron optics

    CERN Document Server

    Grivet, Pierre; Bertein, F; Castaing, R; Gauzit, M; Septier, Albert L

    1972-01-01

    Electron Optics, Second English Edition, Part I: Optics is a 10-chapter book that begins by elucidating the fundamental features and basic techniques of electron optics, as well as the distribution of potential and field in electrostatic lenses. This book then explains the field distribution in magnetic lenses; the optical properties of electrostatic and magnetic lenses; and the similarities and differences between glass optics and electron optics. Subsequent chapters focus on lens defects; some electrostatic lenses and triode guns; and magnetic lens models. The strong focusing lenses and pris

  5. Optical Solitons

    Science.gov (United States)

    Taylor, J. R.

    2005-08-01

    1. Optical solitons in fibres: theoretical review A. Hasegawa; 2. Solitons in optical fibres: an experimental account L. F. Mollenauer; 3. All-optical long-distance soliton-based transmission systems K. Smith and L. F. Mollenauer; 4. Nonlinear propagation effects in optical fibres: numerical studies K. J. Blow and N. J. Doran; 5. Soliton-soliton interactions C. Desem and P. L. Chu; 6. Soliton amplification in erbium-doped fibre amplifiers and its application to soliton communication M. Nakazawa; 7. Nonlinear transformation of laser radiation and generation of Raman solitons in optical fibres E. M. Dianov, A. B. Grudinin, A. M. Prokhorov and V. N. Serkin; 8. Generation and compression of femtosecond solitons in optical fibers P. V. Mamyshev; 9. Optical fibre solitons in the presence of higher order dispersion and birefringence C. R. Menyuk and Ping-Kong A. Wai; 10. Dark optical solitons A. M. Weiner; 11. Soliton Raman effects J. R. Taylor; Bibliography; Index.

  6. Optical biosensors

    OpenAIRE

    Damborský, Pavel; Švitel, Juraj; Katrlík, Jaroslav

    2016-01-01

    Optical biosensors represent the most common type of biosensor. Here we provide a brief classification, a description of underlying principles of operation and their bioanalytical applications. The main focus is placed on the most widely used optical biosensors which are surface plasmon resonance (SPR)-based biosensors including SPR imaging and localized SPR. In addition, other optical biosensor systems are described, such as evanescent wave fluorescence and bioluminescent optical fibre biose...

  7. Optical keyboard

    Science.gov (United States)

    Veligdan, James T.; Feichtner, John D.; Phillips, Thomas E.

    2001-01-01

    An optical keyboard includes an optical panel having optical waveguides stacked together. First ends of the waveguides define an inlet face, and opposite ends thereof define a screen. A projector transmits a light beam outbound through the waveguides for display on the screen as a keyboard image. A light sensor is optically aligned with the inlet face for sensing an inbound light beam channeled through the waveguides from the screen upon covering one key of the keyboard image.

  8. All-optical reservoir computing.

    Science.gov (United States)

    Duport, François; Schneider, Bendix; Smerieri, Anteo; Haelterman, Marc; Massar, Serge

    2012-09-24

    Reservoir Computing is a novel computing paradigm that uses a nonlinear recurrent dynamical system to carry out information processing. Recent electronic and optoelectronic Reservoir Computers based on an architecture with a single nonlinear node and a delay loop have shown performance on standardized tasks comparable to state-of-the-art digital implementations. Here we report an all-optical implementation of a Reservoir Computer, made of off-the-shelf components for optical telecommunications. It uses the saturation of a semiconductor optical amplifier as nonlinearity. The present work shows that, within the Reservoir Computing paradigm, all-optical computing with state-of-the-art performance is possible.

  9. Stabilisation of a fibre frequency synthesiser using acousto-optical and electro-optical modulators

    Science.gov (United States)

    Koliada, N. A.; Nyushkov, B. N.; Pivtsov, V. S.; Dychkov, A. S.; Farnosov, S. A.; Denisov, V. I.; Bagayev, S. N.

    2016-12-01

    A fibre-optic frequency synthesiser is developed that is stabilised to the optical frequency standard based on molecular iodine ({\\text{Nd : YAG/I}}2). The possibility of transferring stability of the optical frequency standard to other optical frequencies in the IR range 1 - 2 \\unicode{956}{\\text{m}} and to the RF range by using synthesiser phase-locked loops (PLLs) with acousto-optical and electro-optical modulators is experimentally demonstrated. The additive instability introduced into the optical frequency comb of the synthesiser (which arises due to PLL residual random errors) is several orders less than the intrinsic instability of the reference optical frequency standard employed (i.e., is noticeably less than 1 × 10-13 for 1 {\\text{s}} and 5 × 10-15 for 1000 {\\text{s}}).

  10. Optical interconnects

    CERN Document Server

    Chen, Ray T

    2006-01-01

    This book describes fully embedded board level optical interconnect in detail including the fabrication of the thin-film VCSEL array, its characterization, thermal management, the fabrication of optical interconnection layer, and the integration of devices on a flexible waveguide film. All the optical components are buried within electrical PCB layers in a fully embedded board level optical interconnect. Therefore, we can save foot prints on the top real estate of the PCB and relieve packaging difficulty reduced by separating fabrication processes. To realize fully embedded board level optical

  11. Optical fibres

    CERN Document Server

    Geisler, J; Boutruche, J P

    1986-01-01

    Optical Fibers covers numerous research works on the significant advances in optical fibers, with particular emphasis on their application.This text is composed of three parts encompassing 15 chapters. The first part deals with the manufacture of optical fibers and the materials used in their production. The second part describes optical-fiber connectors, terminals and branches. The third part is concerned with the major optoelectronic components encountered in optical-communication systems.This book will be of value to research scientists, engineers, and patent workers.

  12. Nonlinear optics

    CERN Document Server

    Boyd, Robert W

    2013-01-01

    Nonlinear Optics is an advanced textbook for courses dealing with nonlinear optics, quantum electronics, laser physics, contemporary and quantum optics, and electrooptics. Its pedagogical emphasis is on fundamentals rather than particular, transitory applications. As a result, this textbook will have lasting appeal to a wide audience of electrical engineering, physics, and optics students, as well as those in related fields such as materials science and chemistry.Key Features* The origin of optical nonlinearities, including dependence on the polarization of light* A detailed treatment of the q

  13. Journal standards.

    Science.gov (United States)

    Jackson, R

    2003-08-01

    Despite its many imperfections, the peer review process is a firmly established quality control system for scientific literature. It gives readers some assurance that the work and views that are reported meet standards that are acceptable to a journal. Maureen Revington's editorial in a recent issue of the Australian Veterinary Journal (Revington2002) gives a good concise warts and all overview of the process and is well worth reading. I have some concerns about several articles in the December 2002 issue of the New Zealand Veterinary Journal (Volume 50, Number 6), devoted to the health and welfare of farmed deer, that relate to extensive citing of non-peer reviewed papers. I can understand the need for information to flow from researchers to the wider community but that need is already satisfied by publications such as the proceedings of the Deer Branch of the New Zealand Veterinary Association and Proceedings of the New Zealand Society of Animal Production. Non-peer reviewed papers have been cited in the Journal in the past but never to the extent displayed in this particular issue. It degrades the peer-review process and creates an added burden for reviewers who are forced to grapple with the uncertainties of the science in non-peer reviewed citations. One of my fears is that this process allows science from non peer reviewed articles to be legitimised by its inclusion in a peer reviewed journal and perhaps go on to be accepted as dogma. This is a real danger given the difficulties associated with tracing back to original citations and the increasing volume of scientific literature. It also affords opportunities for agencies to pick up questionable and doubtful science and tout it as support for their products or particular points of view. If deer researchers choose to publish most of their work in proceedings then so be it. However this approach, which seems to becoming increasingly prevalent in the deer sector, is questionable from an established science point

  14. Unilateral Optic Nerve Hypoplasia with Contralateral Optic Pathway Hypoplasia: A Case Report.

    Science.gov (United States)

    Nishi, Tomo; Yukawa, Eiichi; Taoka, Toshiaki; Ogata, Nahoko

    2013-01-01

    Optic nerve hypoplasia is diagnosed by the ophthalmoscopic appearance of the fundus of the eye and by standard magnetic resonance imaging of the brain. The ability to study eyes with optic nerve hypoplasia by magnetic resonance diffusion tensor imaging has improved the evaluation of the optic pathways. The authors report a case of unilateral optic nerve hypoplasia with hypoplasia of the contralateral optic pathway. The entire visual pathway of this patient was examined by magnetic resonance and magnetic resonance diffusion tensor imaging. The images show a decrease of the volume of the optic radiation contralateral to the optic nerve abnormality and also pre- and post-chiasmal abnormalities.

  15. All-optical fast random number generator.

    Science.gov (United States)

    Li, Pu; Wang, Yun-Cai; Zhang, Jian-Zhong

    2010-09-13

    We propose a scheme of all-optical random number generator (RNG), which consists of an ultra-wide bandwidth (UWB) chaotic laser, an all-optical sampler and an all-optical comparator. Free from the electric-device bandwidth, it can generate 10Gbit/s random numbers in our simulation. The high-speed bit sequences can pass standard statistical tests for randomness after all-optical exclusive-or (XOR) operation.

  16. Optical computer motherboards

    Science.gov (United States)

    Jannson, Tomasz P.; Xu, Guoda; Bartha, John M.; Gruntman, Michael A.

    1997-09-01

    In this paper, we investigate the application of precision plastic optics into a communication/computer sub-system, such as a hybrid computer motherboard. We believe that using optical waveguides for next-generation computer motherboards can provide a high performance alternative for present multi-layer printed circuit motherboards. In response to this demand, we suggest our novel concept of a hybrid motherboard based on an internal-fiber-coupling (IFC) wavelength-division-multiplexing (WDM) optical backplane. The IFC/WDM backplane provides dedicated Tx/Rx connections, and applies low-cost, high-performance components, including CD LDs, GRIN plastic fibers, molding housing, and nonimaging optics connectors. Preliminary motherboard parameters are: speed 100 MHz/100 m, or 1 GHz/10 m; fiber loss approximately 0.01 dB/m; almost zero fan-out/fan-in optical power loss, and eight standard wavelength channels. The proposed hybrid computer motherboard, based on innovative optical backplane technology, should solve low-speed, low-parallelism bottlenecks in present electric computer motherboards.

  17. Applied optics and optical design

    CERN Document Server

    Conrady, A E

    2011-01-01

    ""For the optical engineer it is an indispensable work."" - Journal, Optical Society of America""As a practical guide this book has no rival."" - Transactions, Optical Society""A noteworthy contribution,"" - Nature (London)Part I covers all ordinary ray-tracing methods, together with the complete theory of primary aberrations and as much of higher aberration as is needed for the design of telescopes, low-power microscopes and simple optical systems. Chapters: Fundamental Equations, Spherical Aberration, Physical Aspect of Optical Images, Chromatic Aberration, Design of Achromatic Object-Glass

  18. Optical electronics

    CERN Document Server

    Yariv, Amnon

    1991-01-01

    This classic text introduces engineering students to the first principles of major phenomena and devices of optoelectronics and optical communication technology. Yariv's "first principles" approach employs real-life examples and extensive problems. The text includes separate chapters on quantum well and semiconductor lasers, as well as phase conjugation and its applications. Optical fiber amplification, signal and noise considerations in optical fiber systems, laser arrays and distributed feedback lasers all are covered extensively in major sections within chapters.

  19. [Optic neuritis].

    Science.gov (United States)

    Wilhelm, H; Heine, C; Tonagel, F

    2014-11-01

    Optic neuritis is a frequent neuro-ophthalmological disease in which the diagnosis can be based on just a few symptoms and findings. It is not only important to differentiate from other optic nerve disorders but also to recognise special types of optic neuritis, which is mostly only possible during the course of the disease. This article presents a review of the current state in diagnosis and therapy from the authors' personal point of view.

  20. Terahertz wave electro-optic measurements with optical spectral filtering

    Energy Technology Data Exchange (ETDEWEB)

    Ilyakov, I. E., E-mail: igor-ilyakov@mail.ru; Shishkin, B. V. [Institute of Applied Physic RAS, Nizhny Novgorod 603950 (Russian Federation); Kitaeva, G. Kh. [Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Akhmedzhanov, R. A. [Institute of Applied Physic RAS, Nizhny Novgorod 603950 (Russian Federation); N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod 603950 (Russian Federation)

    2015-03-23

    We propose electro-optic detection techniques based on variations of the laser pulse spectrum induced during pulse co-propagation with terahertz wave radiation in a nonlinear crystal. Quantitative comparison with two other detection methods is made. Substantial improvement of the sensitivity compared to the standard electro-optic detection technique (at high frequencies) and to the previously shown technique based on laser pulse energy changes is demonstrated in experiment.

  1. Optical Detectors

    Science.gov (United States)

    Tabbert, Bernd; Goushcha, Alexander

    Optical detectors are applied in all fields of human activities from basic research to commercial applications in communication, automotive, medical imaging, homeland security, and other fields. The processes of light interaction with matter described in other chapters of this handbook form the basis for understanding the optical detectors physics and device properties.

  2. Optic neuritis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Roed, H; Sellebjerg, F

    2004-01-01

    To study the involvement of the chemokine receptor CXCR3 and its ligands (CXCL9/Mig, CXCL10/IP-10, CXCL11/ITAC) in optic neuritis (ON).......To study the involvement of the chemokine receptor CXCR3 and its ligands (CXCL9/Mig, CXCL10/IP-10, CXCL11/ITAC) in optic neuritis (ON)....

  3. Optical biosensors

    Science.gov (United States)

    Damborský, Pavel; Švitel, Juraj

    2016-01-01

    Optical biosensors represent the most common type of biosensor. Here we provide a brief classification, a description of underlying principles of operation and their bioanalytical applications. The main focus is placed on the most widely used optical biosensors which are surface plasmon resonance (SPR)-based biosensors including SPR imaging and localized SPR. In addition, other optical biosensor systems are described, such as evanescent wave fluorescence and bioluminescent optical fibre biosensors, as well as interferometric, ellipsometric and reflectometric interference spectroscopy and surface-enhanced Raman scattering biosensors. The optical biosensors discussed here allow the sensitive and selective detection of a wide range of analytes including viruses, toxins, drugs, antibodies, tumour biomarkers and tumour cells. PMID:27365039

  4. Lagrangian optics

    CERN Document Server

    Lakshminarayanan, Vasudevan; Thyagarajan, K

    2002-01-01

    Ingeometrical optics, light propagation is analyzed in terms of light rays which define the path of propagation of light energy in the limitofthe optical wavelength tending to zero. Many features oflight propagation can be analyzed in terms ofrays,ofcourse, subtle effects near foci, caustics or turning points would need an analysis based on the wave natureoflight. Allofgeometric optics can be derived from Fermat's principle which is an extremum principle. The counterpart in classical mechanics is of course Hamilton's principle. There is a very close analogy between mechanics ofparticles and optics oflight rays. Much insight (and useful results) can be obtained by analyzing these analogies. Asnoted by H. Goldstein in his book Classical Mechanics (Addison Wesley, Cambridge, MA, 1956), classical mechanics is only a geometrical optics approximation to a wave theory! In this book we begin with Fermat's principle and obtain the Lagrangian and Hamiltonian pictures of ray propagation through various media. Given the ...

  5. Superconducting optical modulator

    Science.gov (United States)

    Bunt, Patricia S.; Ference, Thomas G.; Puzey, Kenneth A.; Tanner, David B.; Tache, Nacira; Varhue, Walter J.

    2000-12-01

    An optical modulator based on the physical properties of high temperature superconductors has been fabricated and tested. The modulator was constructed form a film of Yttrium Barium Copper Oxide (YBCO) grown on undoped silicon with a buffer layer of Yttria Stabilized Zirconia. Standard lithographic procedures were used to pattern the superconducting film into a micro bridge. Optical modulation was achieved by passing IR light through the composite structure normal to the micro bridge and switching the superconducting film in the bridge region between the superconducting and non-superconducting states. In the superconducting state, IR light reflects from the superconducting film surface. When a critical current is passed through the micro bridge, it causes the film in this region to switch to the non-superconducting state allowing IR light to pass through it. Superconducting materials have the potential to switch between these two states at speeds up to 1 picosecond using electrical current. Presently, fiber optic transmission capacity is limited by the rate at which optical data can be modulated. The superconducting modulator, when combined with other components, may have the potential to increase the transmission capacity of fiber optic lines.

  6. Hanle Detection for Optical Clocks

    Directory of Open Access Journals (Sweden)

    Xiaogang Zhang

    2015-01-01

    Full Text Available Considering the strong inhomogeneous spatial polarization and intensity distribution of spontaneous decay fluorescence due to the Hanle effect, we propose and demonstrate a universe Hanle detection configuration of electron-shelving method for optical clocks. Experimental results from Ca atomic beam optical frequency standard with electron-shelving method show that a designed Hanle detection geometry with optimized magnetic field direction, detection laser beam propagation and polarization direction, and detector position can improve the fluorescence collection rate by more than one order of magnitude comparing with that of inefficient geometry. With the fixed 423 nm fluorescence, the improved 657 nm optical frequency standard signal intensity is presented. The potential application of the Hanle detection geometry designed for facilitating the fluorescence collection for optical lattice clock with a limited solid angle of the fluorescence collection has been discussed. The Hanle detection geometry is also effective for ion detection in ion optical clock and quantum information experiments. Besides, a cylinder fluorescence collection structure is designed to increase the solid angle of the fluorescence collection in Ca atomic beam optical frequency standard.

  7. Nonlinear optics

    CERN Document Server

    Bloembergen, Nicolaas

    1996-01-01

    Nicolaas Bloembergen, recipient of the Nobel Prize for Physics (1981), wrote Nonlinear Optics in 1964, when the field of nonlinear optics was only three years old. The available literature has since grown by at least three orders of magnitude.The vitality of Nonlinear Optics is evident from the still-growing number of scientists and engineers engaged in the study of new nonlinear phenomena and in the development of new nonlinear devices in the field of opto-electronics. This monograph should be helpful in providing a historical introduction and a general background of basic ideas both for expe

  8. Optical holography

    CERN Document Server

    Collier, Robert

    2013-01-01

    Optical Holography deals with the use of optical holography to solve technical problems, with emphasis on the properties of holograms formed with visible light. Topics covered include the Fourier transform, propagation and diffraction, pulsed-laser holography, and optical systems with spherical lenses. A geometric analysis of point-source holograms is also presented, and holograms and hologram spatial filters formed with spatially modulated reference waves are described. This book is comprised of 20 chapters and begins with an introduction to concepts that are basic to understanding hologr

  9. [Differentiation of concomitant glaucomatous optic neuropathy in optic disc drusen].

    Science.gov (United States)

    Mamikonian, V R; Galoian, N S; Sheremet, N L; Kazarian, E E; Kharlap, S I; Shemeleva-Demir, O A; Tatevosian, A A; Andzhelova, D V; Eksarenko, O V

    2013-01-01

    Characteristics of ocular blood flow (OBF) in primary open-angle glaucoma (POAG) in eyes with optic disc drusen have been investigated. The study enrolled 21 patient (35 eyes) with optic disc drusen, of which 7 (8 eyes) were diagnosed with POAG. Besides the standard tests, the ophthalmological assessment included evaluation of OBF (flowmetry) and an individual normal range of intraocular pressure (IOP). The results showed that optic disc drusen are not associated with OBF changes. Concomitant POAG might be suspected in a patient with optic disc drusen whose OBF is significantly decreased and IOP is above the individual normal range. Differentiation of morphofunctional changes in chronic optic neuropathy, which might be due to either glaucomatous optic neuropathy or optic disc drusen, is complicated when actual IOP lies within the average normal range. Ocular blood flow evaluation by means of flowmetry with calculation of an individual normal range of IOP has been demonstrated as a highly effective predictor of concomitant POAG in patients with optic disc drusen.

  10. Quantum optics

    DEFF Research Database (Denmark)

    Andersen, Ulrik Lund

    2013-01-01

    Further sensitivity improvements are required before advanced optical interferometers will be able to measure gravitational waves. A team has now shown that introducing quantum squeezing of light may help to detect these elusive waves.......Further sensitivity improvements are required before advanced optical interferometers will be able to measure gravitational waves. A team has now shown that introducing quantum squeezing of light may help to detect these elusive waves....

  11. Quantum optics

    DEFF Research Database (Denmark)

    Andersen, Ulrik Lund

    2013-01-01

    Further sensitivity improvements are required before advanced optical interferometers will be able to measure gravitational waves. A team has now shown that introducing quantum squeezing of light may help to detect these elusive waves.......Further sensitivity improvements are required before advanced optical interferometers will be able to measure gravitational waves. A team has now shown that introducing quantum squeezing of light may help to detect these elusive waves....

  12. Standards for Standardized Logistic Regression Coefficients

    Science.gov (United States)

    Menard, Scott

    2011-01-01

    Standardized coefficients in logistic regression analysis have the same utility as standardized coefficients in linear regression analysis. Although there has been no consensus on the best way to construct standardized logistic regression coefficients, there is now sufficient evidence to suggest a single best approach to the construction of a…

  13. Instant standard concept for data standards development

    NARCIS (Netherlands)

    Folmer, E.; Kulcsar, I.Z.; Roes, J.

    2013-01-01

    This paper presents the current results of an ongoing research about a new data standards development concept. The concept is called Instant Standard referring to the pressure that is generated by shrinking the length of the standardization process. Based on this concept it is estimated that the dev

  14. Standards for Standardized Logistic Regression Coefficients

    Science.gov (United States)

    Menard, Scott

    2011-01-01

    Standardized coefficients in logistic regression analysis have the same utility as standardized coefficients in linear regression analysis. Although there has been no consensus on the best way to construct standardized logistic regression coefficients, there is now sufficient evidence to suggest a single best approach to the construction of a…

  15. Ocean optics

    Energy Technology Data Exchange (ETDEWEB)

    Spinard, R.W.; Carder, K.L.; Perry, M.J.

    1994-12-31

    This volume is the twenty fifth in the series of Oxford Monographs in Geology and Geophysics. The propagation off light in the hydra-atmosphere systems is governed by the integral-differential Radiative Transfer Equation (RTE). Closure and inversion are the most common techniques in optical oceanography to understand the most basic principles of natural variability. Three types of closure are dealt with: scale closure, experimental closure, and instrument closure. The subject is well introduced by Spinard et al. in the Preface while Howard Gordon in Chapter 1 provides an in-depth introduction to the RTE and its inherent problems. Inherent and apparent optical properties are dealt with in Chapter 2 by John Kirk and the realities of optical closure are presented in the following chapter by Ronald Zaneveld. The balance of the papers in this volume is quite varied. The early papers deal in a very mathematical manner with the basics of radiative transfer and the relationship between inherent and optical properties. Polarization of sea water is discussed in a chapter that contains a chronological listing of discoveries in polarization, starting at about 1000 AD with the discovery of dichroic properties of crystals by the Vikings and ending with the demonstration of polarotaxis in certain marine organisms by Waterman in 1972. Chapter 12 on Raman scattering in pure water and the pattern recognition techniques presented in Chapter 13 on the optical effects of large particles may be of relevance to fields outside ocean optics.

  16. Optic nerve atrophy

    Science.gov (United States)

    Optic atrophy; Optic neuropathy ... There are many causes of optic atrophy. The most common is poor blood flow. This is called ischemic optic neuropathy. The problem most often affects older adults. The optic ...

  17. Dielectric optical invisibility cloaks

    Science.gov (United States)

    Blair, J.; Tamma, V. A.; Park, W.; Summers, C. J.

    2010-08-01

    Recently, metamaterial cloaks for the microwave frequency range have been designed using transformative optics design techniques and experimentally demonstrated. The design of these structures requires extreme values of permittivity and permeability within the device, which has been accomplished by the use of resonating metal elements. However, these elements severely limit the operating frequency range of the cloak due to their non-ideal dispersion properties at optical frequencies. In this paper we present designs to implement a simpler demonstration of cloaking, the carpet cloak, in which a curved reflective surface is compressed into a flat reflective surface, effectively shielding objects behind the curve from view with respect to the incoming radiation source. This approach eliminates the need for metallic resonant elements. These structures can now be fabricated using only high index dielectric materials by the use of electron beam lithography and standard cleanroom technologies. The design method, simulation analysis, device fabrication, and near field optical microscopy (NSOM) characterization results are presented for devices designed to operate in the 1400-1600nm wavelength range. Improvements to device performance by the deposition/infiltration of linear, and potentially non-linear optical materials, were investigated.

  18. Calibration of the optical torque wrench

    NARCIS (Netherlands)

    Pedaci, F.; Huang, Z.; Van Oene, M.; Dekker, N.H.

    2012-01-01

    The optical torque wrench is a laser trapping technique that expands the capability of standard optical tweezers to torque manipulation and measurement, using the laser linear polarization to orient tailored microscopic birefringent particles. The ability to measure torque of the order of kBT (∼4 pN

  19. Micro-optics: manufacturing and characterization

    Science.gov (United States)

    Voelkel, R.; Eisner, M.; Weible, K. J.

    2005-10-01

    Wafer-based manufacturing of Micro-Optics is based on standard technologies from Semiconductor Industry, like resist coating, lithography, reactive ion etching, deposition, sputtering, and lift-off. These well-established technologies allow the manufacturing of almost any Micro-Optics' structure shape. The excellence of the Micro-Optics component depends much on the proper choice of the manufacturing equipment and the process control. As all processes are standard Semiconductor technology, the quality is merely a question of the budget and the optimization effort. For characterization and testing, the current situation is different. Neither the test equipment from Semiconductor industry nor the test equipment from classical optics manufacturing is suitable to for Micro-Optics. Most of test instruments Micro-Optics industry is using today have been developed by research institutes or by the manufacturing companies themselves. As Micro-Optics is still a niche market, all instruments are built in small series. This lack of suitable test equipment is a major problem for the Micro-Optics industry today. All process optimization in manufacturing is closely related to the capability to measure the quality of the products. We report on the state of the art in wafer-based manufacturing and summarize the standard characterization tools for Micro-Optics.

  20. Polymer optical fiber fuse

    CERN Document Server

    Mizuno, Yosuke; Tanaka, Hiroki; Nakamura, Kentaro

    2013-01-01

    Although high-transmission-capacity optical fibers are in demand, the problem of the fiber fuse phenomenon needs to be resolved to prevent the destruction of fibers. As polymer optical fibers become more prevalent, clarifying their fuse properties has become important. Here, we experimentally demonstrate a fuse propagation velocity of 21.9 mm/s, which is 1 to 2 orders of magnitude slower than that in standard silica fibers. The achieved threshold power density and proportionality constant between the propagation velocity and the power density are respectively 1/186 of and 16.8 times the values for silica fibers. An oscillatory continuous curve instead of periodic voids is formed after the passage of the fuse. An easy fuse termination method is presented herein, along with its potential plasma applications.

  1. Optical developments for optogenetics.

    Science.gov (United States)

    Papagiakoumou, Eirini

    2013-10-01

    Brain intricacies and the difficulty that scientists encounter in revealing its function with standard approaches such as electrical stimulation of neurons have led to the exploration of new tools that enable the study of neural circuits in a remote and non-invasive way. To this end, optogenetics has initialised a revolution for neuroscience in the last decade by enabling simultaneous monitoring and stimulation of specific neuronal populations in intact brain preparations through genetically targeted expression of light sensitive proteins and molecular photoswitches. In addition to ongoing molecular probe development and optimisation, novel optical techniques hold immense potential to amplify and diversify the utility of optogenetic methods. Importantly, by improving the spatio-temporal resolution of light stimulation, neural circuits can be photoactivated in patterns mimicking endogenous physiological processes. The following synopsis addresses the possibilities and limitations of optical stimulation methods applied to and developed for activation of neuronal optogenetic tools.

  2. All optical OFDM transmission for passive optical networks

    Science.gov (United States)

    Kachare, Nitin; Ashik T., J.; Bai, K. Kalyani; Kumar, D. Sriram

    2017-06-01

    This paper demonstrates the idea of data transmission at a very higher rate (Tbits/s) through optical fibers in a passive optical network using the most efficient data transmission technique widely used in wireless communication that is orthogonal frequency division multiplexing. With an increase in internet users, data traffic has also increased significantly and the current dense wavelength division multiplexing (DWDM) systems may not support the next generation passive optical networks (PONs) requirements. The approach discussed in this paper allows to increase the downstream data rate per user and extend the standard single-mode fiber reach for future long-haul applications. All-optical OFDM is a promising solution for terabit per second capable single wavelength transmission, with high spectral efficiency and high tolerance to chromatic dispersion.

  3. Optics Demonstrations Using Cylindrical Lenses

    Science.gov (United States)

    Ivanov, Dragia; Nikolov, Stefan

    2015-01-01

    In this paper we consider the main properties of cylindrical lenses and propose several demonstrational experiments that can be performed with them. Specifically we use simple glasses full of water to demonstrate some basic geometrical optics principles and phenomena. We also present some less standard experiments that can be performed with such…

  4. Standards help enterprises

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Standardization in modern times began from the Industrial Revolution. Various industrial sectors, for which about 300 standardization technical commissions have been established, make up the key fields of China's standardization.

  5. Optical memory

    Science.gov (United States)

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

    Optical memory comprising: a semiconductor wire, a first electrode, a second electrode, a light source, a means for producing a first voltage at the first electrode, a means for producing a second voltage at the second electrode, and a means for determining the presence of an electrical voltage across the first electrode and the second electrode exceeding a predefined voltage. The first voltage, preferably less than 0 volts, different from said second voltage. The semiconductor wire is optically transparent and has a bandgap less than the energy produced by the light source. The light source is optically connected to the semiconductor wire. The first electrode and the second electrode are electrically insulated from each other and said semiconductor wire.

  6. Semiconductor Optics

    CERN Document Server

    Klingshirn, Claus F

    2012-01-01

    This updated and enlarged new edition of Semiconductor Optics provides an introduction to and an overview of semiconductor optics from the IR through the visible to the UV, including linear and nonlinear optical properties, dynamics, magneto and electrooptics, high-excitation effects and laser processes, some applications, experimental techniques and group theory. The mathematics is kept as elementary as possible, sufficient for an intuitive understanding of the experimental results and techniques treated. The subjects covered extend from physics to materials science and optoelectronics. Significantly updated chapters add coverage of current topics such as electron hole plasma, Bose condensation of excitons and meta materials. Over 120 problems, chapter introductions and a detailed index make it the key textbook for graduate students in physics. The mathematics is kept as elementary as possible, sufficient for an intuitive understanding of the experimental results and techniques treated. The subjects covered ...

  7. CODEX optics

    Science.gov (United States)

    Delabre, Bernard; Manescau, Antonio

    2010-07-01

    CODEX is a high resolution spectrograph for the ESO E-ELT. A classical spectrograph can only achieve a resolution of about 120.000 on a 42 m telescope with extremely large echelle gratings and cameras. This paper describes in detail the optical concept of CODEX, which uses only optical elements size similar to those in current high resolution spectrographs. This design is based on slicers, anamorphic beams and slanted VPHG as cross dispersers. In this new version of the CODEX design, no special expensive materials as calcium fluoride or abnormal dispersion glasses are needed. The optical quality is excellent and compatible with 10K x 10K detectors with 10 μm pixels.

  8. Standard Reference Tables -

    Data.gov (United States)

    Department of Transportation — The Standard Reference Tables (SRT) provide consistent reference data for the various applications that support Flight Standards Service (AFS) business processes and...

  9. Statistical optics

    CERN Document Server

    Goodman, Joseph W

    2015-01-01

    This book discusses statistical methods that are useful for treating problems in modern optics, and the application of these methods to solving a variety of such problems This book covers a variety of statistical problems in optics, including both theory and applications.  The text covers the necessary background in statistics, statistical properties of light waves of various types, the theory of partial coherence and its applications, imaging with partially coherent light, atmospheric degradations of images, and noise limitations in the detection of light. New topics have been introduced i

  10. Reflective optics

    CERN Document Server

    Korsch, Dietrich

    1991-01-01

    This is the first book dedicated exclusively to all-reflective imaging systems. It is a teaching tool as well as a practical design tool for anyone who specializes in optics, particularly for those interested in telescopes, infrared, and grazing-incidence systems. The first part of the book describes a unified geometric optical theory of all-reflective imaging systems (from near-normal to grazing incidence) developed from basic principles. The second part discusses correction methods and a multitude of closed-form solutions of well-corrected systems, supplemented with many conventional and unc

  11. Realisation of a Frequency Standard Using an Atomic Fountain

    CERN Document Server

    Michaud, A; Zetie, K P; Cooper, C J; Hillenbrand, G; Lorent, V; Steane, A; Foot, C J

    2005-01-01

    We report the realisation and preliminary study of a frequency standard using a fountain of laser cooled caesium atoms. Our apparatus uses a magneto-optical trap as a source of cold atoms and optical pumping to prepare the atoms in the correct state before they enter the microwave cavity.

  12. Optical scatter: an overview

    Science.gov (United States)

    Stover, John C.

    1991-12-01

    Optical scatter is a bothersome source of optical noise, limits resolution and reduces system throughput. However, it is also an extremely sensitive metrology tool. It is employed in a wide variety of applications in the optics industry (where direct scatter measurement is of concern) and is becoming a popular indirect measurement in other industries where its measurement in some form is an indicator of another component property - like roughness, contamination or position. This paper presents a brief review of the current state of this technology as it emerges from university and government laboratories into more general industry use. The bidirectional scatter distribution function (or BSDF) has become the common format for expressing scatter data and is now used almost universally. Measurements made at dozens of laboratories around the country cover the spectrum from the uv to the mid- IR. Data analysis of optical component scatter has progressed to the point where a variety of analysis tools are becoming available for discriminating between the various sources of scatter. Work has progressed on the analysis of rough surface scatter and the application of these techniques to some challenging problems outside the optical industry. Scatter metrology is acquiring standards and formal test procedures. The available scatter data base is rapidly expanding as the number and sophistication of measurement facilities increases. Scatter from contaminants is continuing to be a major area of work as scatterometers appear in vacuum chambers at various laboratories across the country. Another area of research driven by space applications is understanding the non-topographic sources of mid-IR scatter that are associated with Beryllium and other materials. The current flurry of work in this growing area of metrology can be expected to continue for several more years and to further expand to applications in other industries.

  13. Optical profilometer

    Science.gov (United States)

    Wieloszyńska, Aleksandra; StrÄ kowski, Marcin

    2016-09-01

    The profilometry plays a huge role in the most fields of science and technology. It allows to measure the profile of the surface with high-resolution. This technique is used in the fields like optic, electronic, medicine, automotive, and much more. The aim of the current work was to design and build optical profilometer based on the interference phenomena. The developed device has been working with He-Ne laser (632.8 nm). The optical parts have been chosen in order to reach the sized 2.0 mm x 1.6 mm of scanning area. The setup of the profilometer is based on Twyman-Green interferometer. Therefore, the phase distribution of the backreflected light from measured surface is recorded. The measurements are carried out with the aid of multiframe algorithms. In this approach we have used the Hariharan algorithm to obtain the exact value of the recorded phase. During tests, which have been carried out in order to check the functionality of the device, the interference patterns have been recoded and processed in order to obtain the 3D profile of measured surface. In this contribution the setup of the optical system, as well as signal processing methods are going to be presented. The brief discussion about the advantages and disadvantages, and usefulness of this approach will be carried out.

  14. Diophantine Optics

    Science.gov (United States)

    Rouan, D.

    2016-09-01

    What I call Diophantine optics is the exploitation in optics of some remarkable algebraic relations between powers of integers. The name comes from Diophantus of Alexandria, a greek mathematician, known as the father of algebra. He studied polynomial equations with integer coefficients and integer solutions, called diophantine equations. Since constructive or destructive interferences are playing with optical path differences which are multiple integer (odd or even) of λ/2 and that the complex amplitude is a highly non-linear function of the optical path difference (or equivalently of the phase), one can understand that any Taylor development of this amplitude implies powers of integers. This is the link with Diophantine equations. We show how, especially in the field of interferometry, remarkable relations between powers of integers can help to solve several problems, such as achromatization of a phase shifter or deep nulling efficiency. It appears that all the research that was conducted in this frame of thinking, relates to the field of detection of exoplanets, a very active domain of astrophysics today.

  15. Optical Processing.

    Science.gov (United States)

    1985-12-31

    34perceptron" (F. Rosenblatt, Principles of Neurodynamics ), workers in the neural network field have been seeking to understand how neural networks can perform...Moscow). 13. F. Rosenblatt, Principles of Neurodynamics , (Spartan, 1962). 14. W. Stoner "Incoherent optical processing via spatially offset pupil

  16. Optical correlation

    NARCIS (Netherlands)

    Boden, J.A.

    1974-01-01

    A survey is given of the most common types of coherent optical correlators, which are classified as spatial plane correlators, frequency plane correlators and special reference correlators. Only the spatial plane correlators are dealt with rather thoroughly. Basic principles, some special features,

  17. Optical metrology

    CERN Document Server

    Gåsvik, Kjell J

    2003-01-01

    New material on computerized optical processes, computerized ray tracing, and the fast Fourier transform, Bibre-Bragg sensors, and temporal phase unwrapping.* New introductory sections to all chapters.* Detailed discussion on lasers and laser principles, including an introduction to radiometry and photometry.* Thorough coverage of the CCD camera.

  18. Pulsed Optics

    Science.gov (United States)

    Hirlimann, C.

    Optics is the field of physics which comprises knowledge on the interaction between light and matter. When the superposition principle can be applied to electromagnetic waves or when the properties of matter do not depend on the intensity of light, one speaks of linear optics. This situation occurs with regular light sources such as light bulbs, low-intensity light-emitting diodes and the sun. With such low-intensity sources the reaction of matter to light can be characterized by a set of parameters such as the index of refraction, the absorption and reflection coefficients and the orientation of the medium with respect to the polarization of the light. These parameters depend only on the nature of the medium. The situation changed dramatically after the development of lasers in the early sixties, which allowed the generation of light intensities larger than a kilowatt per square centimeter. Actual large-scale short-pulse lasers can generate peak powers in the petawatt regime. In that large-intensity regime the optical parameters of a material become functions of the intensity of the impinging light. In 1818 Fresnel wrote a letter to the French Academy of Sciences in which he noted that the proportionality between the vibration of the light and the subsequent vibration of matter was only true because no high intensities were available. The intensity dependence of the material response is what usually defines nonlinear optics.

  19. International Standardization of Bed Rest Standard Measures

    Science.gov (United States)

    Cromwell, Ronita L.

    2010-01-01

    This slide presentation gives an overview of the standardization of bed rest measures. The International Countermeasures Working Group attempted to define and agree internationally on standard measurements for spaceflight based bed rest studies. The group identified the experts amongst several stakeholder agencys. It included information on exercise, muscle, neurological, psychological, bone and cardiovascular measures.

  20. Optical Coherence and Quantum Optics

    CERN Document Server

    Mandel, Leonard

    1995-01-01

    This book presents a systematic account of optical coherence theory within the framework of classical optics, as applied to such topics as radiation from sources of different states of coherence, foundations of radiometry, effects of source coherence on the spectra of radiated fields, coherence theory of laser modes, and scattering of partially coherent light by random media. The book starts with a full mathematical introduction to the subject area and each chapter concludes with a set of exercises. The authors are renowned scientists and have made substantial contributions to many of the topi

  1. Silicon micro-optics for smart light control

    Science.gov (United States)

    Vdovin, Gleb; de Lima Monteiro, Davies W.; Akhzar-Mehr, Ourang; Loktev, Mikhail Y.; Sakarya, Serhat; Soloviev, Oleg; Sarro, Pasqualina M.

    2004-01-01

    We present an overview of the results of our recent research in the field of adaptive optical components based on silicon microtechnologies, including membrane deformable mirrors, spatial light modulators, liquid-crystal correctors, wavefront sensors, and both spherical and aspherical micro-optical components. We aim at the realization of adaptive optical systems using standard-technology solutions.

  2. Optical coherent and envelope detection for photonic wireless communication links

    DEFF Research Database (Denmark)

    Prince, Kamau; Zibar, Darko; Yu, Xianbin;

    We present two novel optical detection techniques for radio over fiber (RoF) communication links. Firstly, we present recent results obtained with optical digital coherent detection of optical phase-modulated ROF signals supporting error-free transmission over 25 km standard SMF with BPSK and QPSK...

  3. Standards and standpoints

    DEFF Research Database (Denmark)

    Nissen, Morten

    2016-01-01

    This article argues that critique is a necessary component in any study of standards, just as it is implied in the concept of standard itself. From this follows the relevance of reflexively situating our research in relation to the cultural-historical development of standards and standardization...

  4. Arizona Academic Standards: Kindergarten

    Science.gov (United States)

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains Arizona public schools' academic standards for kindergarten. The contents of this document include the following: (1) The Arts Standard 2006--Kindergarten; (2) Comprehensive Health Education/Physical Activity Standards 1997--Readiness (Kindergarten); (3) Foreign and Native Language Standards 1997--Readiness…

  5. Creating standards: Creating illusions?

    DEFF Research Database (Denmark)

    Linneberg, Mai Skjøtt

    written standards may open up for the creation of illusions. These are created when written standards' content is not in accordance with the perception standard adopters and standard users have of the specific practice phenomenon's content. This general theoretical argument is exemplified by the specific...

  6. Diffractive Optical Elements for Dynamic Optical Coupling

    Institute of Scientific and Technical Information of China (English)

    Changhe Zhou; Xin Zhao; Liren Liu

    2003-01-01

    Diffractive optical elements such as the complementary Dammann gratings are incorporated for dynamic optical fiber splitting and combining. Experimental results of 1′8 dynamic optical couplings are presented.

  7. Diffractive Optical Elements for Dynamic Optical Coupling

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Diffractive optical elements such as the complementary Dammann gratings are incorporated for dynamic optical fiber splitting and combining. Experimental results of 1×8 dynamic optical couplings are presented.

  8. The Dynamics of Standardization

    DEFF Research Database (Denmark)

    Brunsson, Nils; Rasche, Andreas; Seidl, David

    2012-01-01

    This paper suggests that when the phenomenon of standards and standardization is examined from the perspective of organization studies, three aspects stand out: the standardization of organizations, standardization by organizations and standardization as (a form of) organization. Following......, and show that, while standards and standardization are typically associated with stability and sameness, they are essentially a dynamic phenomenon. The paper highlights the contributions of this special issue to the topic of standards as a dynamic phenomenon in organization studies and makes suggestions...... a comprehensive overview of existing research in these three areas, we argue that the dynamic aspects of standardization are under-represented in the scholarly discourse. Furthermore, we identify the main types of tension associated with standardization and the dynamics they generate in each of those three areas...

  9. Optimizing the next generation optical access networks

    DEFF Research Database (Denmark)

    Amaya Fernández, Ferney Orlando; Soto, Ana Cardenas; Tafur Monroy, Idelfonso

    2009-01-01

    of the optical amplification in the performance of the standardized PON is presented comparing the performance of the EDFA (Erbium Doped Fiber Amplifier) and the distributed Raman amplification. The effect of the Raman amplification in extending the reach of the NG-OAN is analyzed and some requirements......Several issues in the design and optimization of the next generation optical access network (NG-OAN) are presented. The noise, the distortion and the fiber optic nonlinearities are considered to optimize the video distribution link in a passive optical network (PON). A discussion of the effect...

  10. Applied optics and optical engineering v.9

    CERN Document Server

    Shannon, Robert

    1983-01-01

    Applied Optics and Optical Engineering, Volume IX covers the theories and applications of optics and optical engineering. The book discusses the basic algorithms for optical engineering; diffraction gratings, ruled and holographic; and recording and reading of information on optical disks. The text also describes the perfect point spread function; the multiple aperture telescope diffraction images; and the displays and simulators. Ophthalmic optics, as well as the canonical and real-space coordinates used in the theory of image formation are also encompassed. Optical engineers and students tak

  11. Soft optics in intelligent optical networks

    Science.gov (United States)

    Shue, Chikong; Cao, Yang

    2001-10-01

    In addition to the recent advances in Hard-optics that pushes the optical transmission speed, distance, wave density and optical switching capacity, Soft-optics provides the necessary intelligence and control software that reduces operational costs, increase efficiency, and enhances revenue generating services by automating optimal optical circuit placement and restoration, and enabling value-added new services like Optical VPN. This paper describes the advances in 1) Overall Hard-optics and Soft-optics 2) Layered hierarchy of Soft-optics 3) Component of Soft-optics, including hard-optics drivers, Management Soft-optics, Routing Soft-optics and System Soft-optics 4) Key component of Routing and System Soft-optics, namely optical routing and signaling (including UNI/NNI and GMPLS signaling). In summary, the soft-optics on a new generation of OXC's enables Intelligent Optical Networks to provide just-in-time service delivery and fast restoration, and real-time capacity management that eliminates stranded bandwidth. It reduces operational costs and provides new revenue opportunities.

  12. Dumpster Optics: teaching and learning optics without a kit

    Science.gov (United States)

    Donnelly, Judy; Magnani, Nancy; Robinson, Kathleen

    2016-09-01

    The Next Generation Science Standards (NGSS) and renewed emphasis on STEM education in the U.S. have resulted in the development of many educational kits for teaching science in general and optics in particular. Many teachers do not have funding to purchase kits and practical experience has shown that even costly kits can have poorly written and misleading instructions and may include experiments that would not work in a classroom. Dumpster Optics lessons are designed to use inexpensive, commonly found materials. All lessons have been field-tested with students. We will describe the development of the lessons, provide examples of field testing experiences and outline possible future activities.

  13. Chiral quantum optics.

    Science.gov (United States)

    Lodahl, Peter; Mahmoodian, Sahand; Stobbe, Søren; Rauschenbeutel, Arno; Schneeweiss, Philipp; Volz, Jürgen; Pichler, Hannes; Zoller, Peter

    2017-01-25

    Advanced photonic nanostructures are currently revolutionizing the optics and photonics that underpin applications ranging from light technology to quantum-information processing. The strong light confinement in these structures can lock the local polarization of the light to its propagation direction, leading to propagation-direction-dependent emission, scattering and absorption of photons by quantum emitters. The possibility of such a propagation-direction-dependent, or chiral, light-matter interaction is not accounted for in standard quantum optics and its recent discovery brought about the research field of chiral quantum optics. The latter offers fundamentally new functionalities and applications: it enables the assembly of non-reciprocal single-photon devices that can be operated in a quantum superposition of two or more of their operational states and the realization of deterministic spin-photon interfaces. Moreover, engineered directional photonic reservoirs could lead to the development of complex quantum networks that, for example, could simulate novel classes of quantum many-body systems.

  14. Optical aeronomy

    Science.gov (United States)

    Solomon, Stanley C.

    1991-01-01

    Optical measurements of thermospheric and ionospheric processes and their interpretation are reviewed and the chemical reactions and their effects on emissions are discussed. Also included are the phenomena which excite the airglow and aurora, i.e., the solar UV/EUV flux and auroral particle precipitation. Consideration is given to solar flux, atomic emissions, molecular emissions, hydrogen geocorona, and molecular oxygen and the green line nightglow.

  15. Applied Optics

    OpenAIRE

    Han, M; Wang, Anbo

    2004-01-01

    A straightforward theory is presented to accurately model the light inferences in a low-finesse multimode fiber extrinsic Fabry-Perot (FP) interferometer. The effect on the fringe visibility of the gap length, sensor structure imperfections, and modal power distributions is explored. The analysis is particularly useful in the design and optimization of sensors that use an extrinsic FP cavity as the sensing element. (C) 2004 Optical Society of America.

  16. Highly Reliable PON Optical Splitters for Optical Access Networks in Outside Environments

    Science.gov (United States)

    Watanabe, Hiroshi; Araki, Noriyuki; Fujimoto, Hisashi

    Broadband optical access services are spreading throughout the world, and the number of fiber to the home (FTTH) subscribers is increasing rapidly. Telecom operators are constructing passive optical networks (PONs) to provide optical access services. Externally installed optical splitters for PONs are very important passive devices in optical access networks, and they must provide satisfactory performance as outdoor plant over long periods. Therefore, we calculate the failure rate of optical access networks and assign a failure rate to the optical splitters in optical access networks. The maximum cumulative failure rate of 1 × 8 optical splitters was calculated as 0.025 for an optical access fiber length of 2.1km and a 20-year operating lifetime. We examined planar lightwave circuit (PLC) type optical splitters for use as outside plant in terms of their optical characteristics and environmental reliability. We confirmed that PLC type optical splitters have sufficient optical performance for a PON splitter and sufficient reliability as outside plant in accordance with ITU-T standard values. We estimated the lifetimes of three kinds of PLC type optical splitters by using accelerated aging tests. The estimated failure rate of these splitters installed in optical access networks was below the target value for the cumulative failure rate, and we confirmed that they have sufficient reliability to maintain the quality of the network service. We developed 1 × 8 optical splitter modules with plug and socket type optical connectors and optical fiber cords for optical aerial closures designed for use as outside plant. These technologies make it easy to install optical splitters in an aerial optical closure. The optical splitter modules have sufficient optical performance levels for PONs because the insertion loss at the commercially used wavelengths of 1.31 and 1.55µm is less than the criterion established by ITU-T Recommendation G.671 for optical splitters. We performed a

  17. ADVANTAGES OF DIFFRACTIVE OPTICAL ELEMENTS APPLICATION IN SIMPLE OPTICAL IMAGING SYSTEMS

    Directory of Open Access Journals (Sweden)

    N. D. Zoric

    2015-01-01

    Full Text Available The paper deals with the influence of diffractive optical elements on the optical aberrations. The correction of optical aberrations was investigated in the simple optical systems with one and two lenses (singlet and doublet. The advantages of diffractive optical elements are their ability to generate arbitrary complex wave fronts from a piece of optical material that is essentially flat. The optical systems consisting of the standard surfaces were designed and optimized by using the same starting points. Further, the diffractive and aspheric surfaces were introduced into the developed systems. The resulting hybrid systems were optimized. To compare the complicity of the development of narrow field systems and wide field optical systems, the optimization has been done separately for these two types of the instruments. The optical systems were designed by using special Optical Design Software. Тhe characteristics of designed diffractive surfaces were controlled in Software DIFSYS 2.30. Due to the application of diffractive optical elements the longitudinal chromatic aberration was 5 times reduced for the narrow field systems. The absolute value of Seidel coefficient related to the spherical aberration was reduced in the range of 0.03. Considering that diffractive optical elements have the known disadvantages, like possible parasitic diffraction orders and probable decrease of the transmission, we also developed and analyzed the optical systems with combined aspheric and diffractive surfaces. A combination of the aspheric and diffractive surfaces in the optical disk system of the disk reading lens, gave cutting down of the longitudinal color aberrations almost 15 times on-axis, comparing to the lens consisting of the aspherical and standard surfaces. All of the designed diffractive optical elements possess the parameters within the fabrication limits.

  18. Power optics

    Energy Technology Data Exchange (ETDEWEB)

    Apollonov, V V [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2014-02-28

    By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it

  19. Power optics

    Science.gov (United States)

    Apollonov, V. V.

    2014-02-01

    By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it. The

  20. Parallel optical sampler

    Energy Technology Data Exchange (ETDEWEB)

    Tauke-Pedretti, Anna; Skogen, Erik J; Vawter, Gregory A

    2014-05-20

    An optical sampler includes a first and second 1.times.n optical beam splitters splitting an input optical sampling signal and an optical analog input signal into n parallel channels, respectively, a plurality of optical delay elements providing n parallel delayed input optical sampling signals, n photodiodes converting the n parallel optical analog input signals into n respective electrical output signals, and n optical modulators modulating the input optical sampling signal or the optical analog input signal by the respective electrical output signals, and providing n successive optical samples of the optical analog input signal. A plurality of output photodiodes and eADCs convert the n successive optical samples to n successive digital samples. The optical modulator may be a photodiode interconnected Mach-Zehnder Modulator. A method of sampling the optical analog input signal is disclosed.

  1. Portable optical fiber probe for in vivo brain temperature measurements.

    Science.gov (United States)

    Musolino, Stefan; Schartner, Erik P; Tsiminis, Georgios; Salem, Abdallah; Monro, Tanya M; Hutchinson, Mark R

    2016-08-01

    This work reports on the development of an optical fiber based probe for in vivo measurements of brain temperature. By utilizing a thin layer of rare-earth doped tellurite glass on the tip of a conventional silica optical fiber a robust probe, suitable for long-term in vivo measurements of temperature can be fabricated. This probe can be interrogated using a portable optical measurement setup, allowing for measurements to be performed outside of standard optical laboratories.

  2. Water Quality Standards Handbook

    Science.gov (United States)

    The Water Quality Standards Handbook is a compilation of the EPA's water quality standards (WQS) program guidance including recommendations for states, authorized tribes, and territories in reviewing, revising, and implementing WQS.

  3. Radiologic Technology Program Standards.

    Science.gov (United States)

    Georgia Univ., Athens. Dept. of Vocational Education.

    This publication contains statewide standards for the radiologic technology program in Georgia. The standards are divided into 12 categories; Foundations (philosophy, purpose, goals, program objectives, availability, evaluation); Admissions (admission requirements, provisional admission requirements, recruitment, evaluation and planning); Program…

  4. Agent Standards Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation of the work herein proposed is the development of standards for software autonomous agents. These standards are essential to achieve software...

  5. Catalytic Functions of Standards

    NARCIS (Netherlands)

    K. Blind (Knut)

    2009-01-01

    textabstractThe three different areas and the examples have illustrated several catalytic functions of standards for innovation. First, the standardisation process reduces the time to market of inventions, research results and innovative technologies. Second, standards themselves promote the diffusi

  6. Standards and standpoints

    DEFF Research Database (Denmark)

    Nissen, Morten

    2016-01-01

    This article argues that critique is a necessary component in any study of standards, just as it is implied in the concept of standard itself. From this follows the relevance of reflexively situating our research in relation to the cultural-historical development of standards and standardization....... The argument takes off from two different conceptualizations of standards in the literature. On the one hand, standards as immanent to practices (the “Neo-Aristotelian” approach), and on the other hand, standards as imposed to regulate practices (the “neo-pragmatist” and “governmentality” approaches......). It is suggested that this opposition can be superseded by articulating the former alternative, not as an essentialism of “practice,” but as the reflexive assumption of standpoint. Some intricacies of the articulation of standpoint are then discussed, concluding in a proposed dialectics of standard and standpoint....

  7. Catalytic Functions of Standards

    NARCIS (Netherlands)

    K. Blind (Knut)

    2009-01-01

    textabstractThe three different areas and the examples have illustrated several catalytic functions of standards for innovation. First, the standardisation process reduces the time to market of inventions, research results and innovative technologies. Second, standards themselves promote the

  8. Policy,standard,regulation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Automobile Standardization Committee secretariat collects comments on the phase III fuel consumption level limit The Committee intends to formulate the standard based on a comprehensive evaluation of the previous two phases.

  9. Hamilton optics: transformational theory of optics

    Science.gov (United States)

    Winston, Roland; Ge, Wenjun

    2013-09-01

    In 1824 William Rowan Hamilton presented a memoir to the Royal Irish Academy on Optics(Trans. R. Irish. Acacamy, XV, 1828), which was the foundation for transformational optics, classical mechanics, nonimaging optics and thermodynamical foundation of nonimaging optics,etc. It is useful for us even in 2013 to revisit the Hamilton resolution.

  10. Low pumping energy mode of the "optical bars''/"optical lever" topologies of gravitational-wave antennae

    OpenAIRE

    Khalili, F. Ya

    2003-01-01

    The ``optical bars''/``optical lever'' topologies of gravitational-wave antennae allow to obtain sensitivity better that the Standard Quantum Limit while keeping the optical pumping energy in the antenna relatively low. Element of the crucial importance in these schemes is the local meter which monitors the local test mirror position. Using cross-correlation of this meter back-action noise and its measurement noise it is possible to further decrease the optical pumping energy. In this case th...

  11. Efficient single sideband microwave to optical conversion using an electro-optical whispering gallery mode resonator

    CERN Document Server

    Rueda, Alfredo; Collodo, Michele C; Vogl, Ulrich; Stiller, Birgit; Schunk, Gerhard; Strekalov, Dmitry V; Marquardt, Christoph; Fink, Johannes M; Painter, Oskar; Leuchs, Gerd; Schwefel, Harald G L

    2016-01-01

    Linking classical microwave electrical circuits to the optical telecommunication band is at the core of modern communication. Future quantum information networks will require coherent microwave-to-optical conversion to link electronic quantum processors and memories via low-loss optical telecommunication networks. Efficient conversion can be achieved with electro-optical modulators operating at the single microwave photon level. In the standard electro-optic modulation scheme this is impossible because both, up- and downconverted, sidebands are necessarily present. Here we demonstrate true single sideband up- or downconversion in a triply resonant whispering gallery mode resonator by explicitly addressing modes with asymmetric free spectral range. Compared to previous experiments, we show a three orders of magnitude improvement of the electro-optical conversion efficiency reaching 0.1% photon number conversion for a 10GHz microwave tone at 0.42mW of optical pump power. The presented scheme is fully compatible...

  12. Collaboration Between Multistakeholder Standards

    DEFF Research Database (Denmark)

    Rasche, Andreas; Maclean, Camilla

    responsibility is unlikely to support a great variety of partly competing and overlapping standards. Increased collaboration between these standards would enhance both their impact and their adoption by firms. This report examines the nature, benefits, and shortcomings of existing multistakeholder standards...

  13. Questioning the Standard

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Dairy quality standards trigger further controversy China’s dairy industry is once again being scrutinized as suspicions abound that major dairy enterprises played a hand in manipulating and lowering quality standards to save costs.The new standards released in March 2010 set the maximum safety limit for bacteria in raw milk at 2 million cells per milliliter, four times

  14. Evidence Standards and Litigation

    DEFF Research Database (Denmark)

    Guerra, Alice; Luppi, Barbara; Parisi, Francesco

    aspect of the legal system: the evidence standard. We recast the conventional rent-seeking model to consider how alternative evidence standards affect litigation choices. We analyze the interrelation between different evidence standards, the effectiveness of the parties’ efforts, and the merits...

  15. Cloud optics

    CERN Document Server

    Kokhanovsky, A

    2006-01-01

    Clouds affect the climate of the Earth, and they are an important factor in the weather. Therefore, their radiative properties must be understood in great detail. This book summarizes current knowledge on cloud optical properties, for example their ability to absorb, transmit, and reflect light, which depends on the clouds' geometrical and microphysical characteristics such as sizes of droplets and crystals, their shapes, and structures. In addition, problems related to the image transfer through clouds and cloud remote sensing are addressed in this book in great detail. This book can be an im

  16. Quantum Optics

    CERN Document Server

    Garrison, J C

    2008-01-01

    Quantum optics, i.e. the interaction of individual photons with matter, began with the discoveries of Planck and Einstein, but in recent years it has expanded beyond pure physics to become an important driving force for technological innovation. This book serves the broader readership growing out of this development by starting with an elementary description of the underlying physics and then building up a more advanced treatment. The reader is led from the quantum theory of thesimple harmonic oscillator to the application of entangled states to quantum information processing. An equally impor

  17. Optical devices

    Energy Technology Data Exchange (ETDEWEB)

    Chaves, Julio C.; Falicoff, Waqidi; Minano, Juan C.; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-07-13

    An optical manifold for efficiently combining a plurality of blue LED outputs to illuminate a phosphor for a single, substantially homogeneous output, in a small, cost-effective package. Embodiments are disclosed that use a single or multiple LEDs and a remote phosphor, and an intermediate wavelength-selective filter arranged so that backscattered photoluminescence is recycled to boost the luminance and flux of the output aperture. A further aperture mask is used to boost phosphor luminance with only modest loss of luminosity. Alternative non-recycling embodiments provide blue and yellow light in collimated beams, either separately or combined into white.

  18. Information Security Standards

    Directory of Open Access Journals (Sweden)

    Dan Constantin Tofan

    2011-09-01

    Full Text Available The use of standards is unanimously accepted and gives the possibility of comparing a personal security system with a given frame of reference adopted at an international level. A good example is the ISO 9000 set of standards regarding the quality management system, which is a common reference regardless of the industry in which a certain company activates. Just like quality control standards for other industrial processes such as manufacturing and customer service, information security standards demonstrate in a methodical and certifiable manner that an organization conforms to industry best practices and procedures. This article offers a review of the world’s most used information security standards.

  19. Business Standardization & Market Economy

    Institute of Scientific and Technical Information of China (English)

    Li Shiyuan

    2007-01-01

    The introduction of the market economy in China requires a renewed understanding of the theory and practice of business standardization. Built on the basic principles of standardization and the market economics, this paper seeks to define the role and status of standardization in the market economy, its aims and priorities. It then describes the deployment of standardization in market competition. Lastly, it explores into the possible transformations of concepts, functions and associated personnel of enterprise standardization in order to keep abreast of the evolving market economy.

  20. Standardization in Beijing Opera

    Institute of Scientific and Technical Information of China (English)

    Liu Zhiyang

    2012-01-01

    Beijing Opera is the treasure of Chinese traditional dramatic arts.More than 200 years of artistic practice is the process that makes it mature and standardized.Although it is not described by standardized academic terminologies,all the performances of 'Chang (Singing)','Nian(Speaking)','Zuo (Acting)' and 'Da (Fighting)' have been following standardization requirement which is called "Chengshi (pattem)" in professional language or "Fan'er" in jargou,literally meaning a standard pattern.The pattern is the an technology format which is refined and summarized in accordance with the beautify principles from natural forms of things in life and then standardized to be the commonly adhered.

  1. Optical Backplane Interconnection

    Science.gov (United States)

    Hendricks, Herbert D.

    1991-01-01

    Optical backplane interconnection (OBIT), method of optically interconnecting many parallel outputs from data processor to many parallel inputs of other data processors by optically changing wavelength of output optical beam. Requires only one command: exact wavelength necessary to make connection between two desired processors. Many features, including smallness advantageous to incorporate OBIT into integrated optical device. Simplifies or eliminates wiring and speeds transfer of data over existing electrical or optical interconnections. Computer hookups and fiber-optical communication networks benefit from concept.

  2. Standardization of surface contamination analysis systems

    Science.gov (United States)

    Boothe, Richard E.

    1995-01-01

    Corrosion products, oils and greases can potentially degrade material bonding properties. The Marshall Space Flight Center (MSFC) Surface Contamination Analysis Team (SCAT) utilizes a variety of analytical equipment to detect identify and quantify contamination on metallic and non-metallic substrates. Analysis techniques include FT-IR Microscopy (FT-IR), Near Infrared Optical Fiber Spectrometry (NIR), Optically Stimulated Electron Emission (OSEE), Ultraviolet Fluorescence (UVF) and Ellipsometry. To insure that consistent qualitative and quantitative information are obtained, standards are required to develop analysis techniques, to establish instrument sensitivity to potential contaminants, and to develop calibration curves. This paper describes techniques for preparing and preserving contamination standards. Calibration of surface contamination analysis systems is discussed, and methods are presented for evaluating the effects of potential contaminants on bonding properties.

  3. Optical Instruments

    Science.gov (United States)

    1990-01-01

    Precision Lapping and Optical Co. has developed a wide variety of hollow retroreflector systems for applications involving the entire optical spectrum; they are, according to company literature, cheaper, more accurate, lighter and capable of greater size than solid prisms. Precision Lapping's major customers are aerospace and defense companies, government organizations, R&D and commercial instrument companies. For example, Precision Lapping supplies hollow retroreflectors for the laser fire control system of the Army's Abrams tank, and retroreflectors have been and are being used in a number of space tests relative to the Air Force's Strategic Defense Initiative research program. An example of a customer/user is Chesapeake Laser Systems, producer of the Laser Tracker System CMS-2000, which has applications in SDI research and industrial robotics. Another customer is MDA Scientific, Inc., manufacturer of a line of toxic gas detection systems used to monitor hazardous gases present in oil fields, refineries, offshore platforms, chemical plants, waste storage sites and other locations where gases are released into the environment.

  4. Standardization, Calibration, and Control in Flow Cytometry.

    Science.gov (United States)

    Wang, Lili; Hoffman, Robert A

    2017-01-05

    Because flow cytometers are designed to measure particle characteristics, particles are the most common materials used to calibrate, control, and standardize the instruments. Definitions and cautions are provided for common terms to alert the reader to critical distinctions in meaning. This unit presents extensive background on particle types and cautions and describes practical aspects of methods to standardize and calibrate instruments. Procedures are provided to characterize performance in terms of optical alignment, fluorescence and light scatter resolution, and sensitivity. Finally, suggestions follow for analyzing particles used for calibration. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  5. 117 Standards Admitted in Civil Administration Standardization Plan

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ The Ministry of Civil Administration has finalized its Standardization Plan 2007. According to this plan, the Ministry will see that 117 standards, including 8 compulsory national standards, 83 recommended national standards, and 26 professional standards, are prepared by June 2008.

  6. Comparison of intraocular lens power calculation using a standard ultrasonic biometer and a new optical biometer%比较标准超声波测量仪和新型光学生物测量仪计算人工晶状体屈光度的准确性

    Institute of Scientific and Technical Information of China (English)

    Faruk Kaya; Ibrahil KoÇak; Ali Aydin; Hakan Baybora; Koray Karadayi

    2016-01-01

    目的:比较超乳手术时应用新型光学生物测量仪和标准超声波测量仪计算人工晶状体的屈光度及屈光结果。  方法:前瞻性研究。研究包含37例37眼白内障患者接受白内障超声乳化联合人工晶状体植入术。同一测量人员分别使用新型光学生物测量仪( Aladdin)与标准超声波测量仪( Sonoled AB 5500)对白内障患者进行检测。通过这两种设备记录生物测定参数,包括眼轴长度、角膜曲率、前房深度及人工晶状体屈光度数。分析术后实际屈光不正与两台设备根据SRK/T公式计算的误差,比较两台设备检查结果的平均估计误差( EE )、平均绝对估计误差( AEE)及生物测定参数。  结果:Aladdin测量仪(23.45±0.73 ll )较超声波测量仪(23.2±0.75 ll)检测出的眼轴显著较长(P=0.01)。Aladdin测量仪的EE与AEE均明显小于超声波测量仪( P=0.0006与0.03)。应用Aladdin测量的大多数眼与目标屈光度相差在±0.5(67%)及±1.00(97%)以内。  结论:Aladdin光学生物测量仪较超声波测量仪更精确,屈光结果更准确。%AlM:To compare the intraocular lens ( lOL ) power calculations and refractive outcomes obtained with a new optical biometer and standard ultrasonic biometer in phacoemulsification surgery. METHODS:Thirty-seven eyes of 37 cataract patients who underwent phacoemulsification with lOL implantation were included in this prospective comparative study. The same operator performed biometer measurements in eyes with cataract using a new optical biometer ( Aladdin) and a standard ultrasonic biometer ( Sonomed AB 5500 ) . Biometric parameters;axial length ( AL ) , keratometric ( K ) readings, anterior chamber depth ( ACD ) and lOL power obtained by two devices were recorded. Postoperative actual refractive errors and errors predicted by two devices according to SRK/T formula were analyzed. The mean estimation error ( EE ) , mean absolute estimation error

  7. Scoring and Standard Setting with Standardized Patients.

    Science.gov (United States)

    Norcini, John J.; And Others

    1993-01-01

    The continuous method of scoring a performance test composed of standardized patients was compared with a derivative method that assigned each of the 131 examinees (medical residents) a dichotomous score, and use of Angoff's method with these scoring methods was studied. Both methods produce reasonable means and distributions of scores. (SLD)

  8. Design and optimization of indoor optical wireless positioning systems

    Science.gov (United States)

    Bergen, Mark H.; Guerrero, Daniel; Jin, Xian; Hristovski, Blago A.; Chaves, Hugo A. L. F.; Klukas, Richard; Holzman, Jonathan F.

    2016-03-01

    Optical wireless (OW) technologies are an emerging field utilizing optical sources to replace existing radio wavelength technologies. The vast majority of work in OW focuses on communication; however, one smaller emerging field is indoor OW positioning. This emerging field essentially aims to replace GPS indoors. One of the primary competing methods in indoor OW positioning is angle-of-arrival (AOA). AOA positioning uses the received vectors from several optical beacons to triangulate its position. The reliability of this triangulation is fundamentally based on two aspects: the geometry of the optical receiver's location compared to the optical beacon locations, and the ability for the optical receiver to resolve the incident vectors correctly. The optical receiver is quantified based on the standard deviation of the azimuthal and polar angles that define the measured vector. The quality of the optical beacon geometry is quantified using dilution of precision (DOP). This proceeding discusses the AOA standard deviation of an ultra-wide field-of-view (FOV) lens along with the DOP characteristics for several optical beacon geometries. The optical beacon geometries used were simple triangle, square, and hexagon optical beacon geometries. To assist the implementation of large optical beacon geometries it is proposed to use both frequency and wavelength division multiplexing. It is found that with an ultra-wide FOV lens, coupled with the appropriately sized optical beacon geometry, allow for high accuracy positioning over a large area. The results of this work will enable reliable OW positioning deployments.

  9. Development of Electro-Optical Standard Processes for Application

    Science.gov (United States)

    2011-11-01

    16 TABLE 5-12. SPECTRAL OR RADIOMETRIC DATA COLLECTED Organization CO2 IR Radiation Solar Irradiance Ozone CN2 Background Spectra P-1 No Yes...RADIOMETER AND SPECIFICATIONS Supplier Model Det Spectral Range (μm) Filter Pass Bands (μm) Frame Rate (Hz) Owne r Qty (Unit) ABB Bomem FTIR MR254...Software Calibration Sources Comments Owner ABB Bomem FTIR MR254 n/a n/a n/a n/a n/a n/a P-1 CI Systems SR5000 n/a n/a n/a n/a n/a n/a P-1

  10. Fiber-based portable optical frequency standard for telecommunication

    DEFF Research Database (Denmark)

    Triches, Marco; Brusch, Anders; Hald, Jan

    2015-01-01

    Gas-filled hollow-core photonic crystal fibers are used to stabilize a fiber laser to the 13C2H2 P(16) (ν1 + ν3) transition at 1542 nm using saturated absorption. The fiber is encapsulated in glass cells for gas handling and compact free-space coupling, and packaged in a easy-to-use configuration...

  11. Advances in nonlinear optics

    CERN Document Server

    Chen, Xianfeng; Zeng, Heping; Guo, Qi; She, Weilong

    2015-01-01

    This book presents an overview of the state of the art of nonlinear optics from weak light nonlinear optics, ultrafast nonlinear optics to electro-optical theory and applications. Topics range from the fundamental studies of the interaction between matter and radiation to the development of devices, components, and systems of tremendous commercial interest for widespread applications in optical telecommunications, medicine, and biotechnology.

  12. Congenital optic tract hypoplasia.

    Science.gov (United States)

    Hatsukawa, Yoshikazu; Fujio, Takahiro; Nishikawa, Masanori; Taylor, David

    2015-08-01

    We report a case of isolated unilateral optic tract hypoplasia, described only twice previously. Bilateral optic disk hypoplasia was seen ophthalmoscopically and visual field studies showed an incongruous right homonymous hemianopia. Magnetic resonance imaging showed bilateral hypoplasia of both optic nerves and the left optic tract. Spectral domain optical coherence tomography mapping correlated well with the visual field studies.

  13. Optical Network Testbeds Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Joe Mambretti

    2007-06-01

    This is the summary report of the third annual Optical Networking Testbed Workshop (ONT3), which brought together leading members of the international advanced research community to address major challenges in creating next generation communication services and technologies. Networking research and development (R&D) communities throughout the world continue to discover new methods and technologies that are enabling breakthroughs in advanced communications. These discoveries are keystones for building the foundation of the future economy, which requires the sophisticated management of extremely large qualities of digital information through high performance communications. This innovation is made possible by basic research and experiments within laboratories and on specialized testbeds. Initial network research and development initiatives are driven by diverse motives, including attempts to solve existing complex problems, the desire to create powerful new technologies that do not exist using traditional methods, and the need to create tools to address specific challenges, including those mandated by large scale science or government agency mission agendas. Many new discoveries related to communications technologies transition to wide-spread deployment through standards organizations and commercialization. These transition paths allow for new communications capabilities that drive many sectors of the digital economy. In the last few years, networking R&D has increasingly focused on advancing multiple new capabilities enabled by next generation optical networking. Both US Federal networking R&D and other national R&D initiatives, such as those organized by the National Institute of Information and Communications Technology (NICT) of Japan are creating optical networking technologies that allow for new, powerful communication services. Among the most promising services are those based on new types of multi-service or hybrid networks, which use new optical networking

  14. International hearing protector standardization

    DEFF Research Database (Denmark)

    Poulsen, Torben

    2002-01-01

    Hearing protectors shall fulfill some minimum requirements to their performance. As hearing protector manufacturers sell the products all over the world, the testing and certification of hearing protectors has become an international issue. The ISO working group WG17 under the headlines Acoustics......, Noise, produce hearing protector standards to be used at an international level. The presentation will cover the ongoing work in WG17, including the revision of existing standards (ISO 4869-1, ISO 4869-3), upcoming new standards (ISO 4869-7) and the plans and status for future standards (performance...... in impulse noise, protectors with active noise reduction). Furthermore, an overview of the present European standards (CEN) and the relation to American and Australian/New Zealand standards will be discussed....

  15. The impact of optic nerve movement on optic nerve magnetic resonance diffusion parameters

    Directory of Open Access Journals (Sweden)

    Anand Moodley

    2014-04-01

    Full Text Available Background: Optic nerve diffusion imaging is a useful investigational tool of optic nerve microstructure, but is limited by eye-movement-induced optic nerve movement and artifacts from surrounding cerebrospinal fluid, fat, bone and air. Attempts at improving patient cooperation, thus voluntarily limiting eye movement during a standard diffusion imagingsequence, are usually futile. The aim of this study was to establish the impact of optic nerve movement on clinical diffusion parameters of the optic nerve.Method: Twenty-nine healthy volunteers with intact vision and intact conjugate gaze were recruited and subjected to magnetic resonance diffusion-weighted imaging (DWI and diffusion-tensor imaging (DTI of the optic nerves. Twenty right eyes had nerve tracking done using single-shot echo-planar imaging at 20 time points over 3 minutes. Optic nerve movement measurements were correlated with diffusion parameters of apparent diffusion coefficient (ADC, mean diffusivity (MD, fractional anisotropy (FA and anisotropic index(AI using Spearman’s rank correlation.Results: No significant correlations were noted between optic nerve movement parameters and ADC in the axial plane and MD of the optic nerve. Low to moderate negative correlations were noted between optic nerve movement parameters and AI and FA and positive correlation with ADC in the radial plane.Conclusion: Optic nerve movement documented during the timespan of standard diffusion sequences (DWI and DTI has a negative effect on the anisotropic diffusion parameters of the optic nerve. With greater eye movement, optic nerve diffusion appears less anisotropic owing to greater radial diffusion.

  16. Optical manifold

    Science.gov (United States)

    Falicoff, Waqidi; Chaves, Julio C.; Minano, Juan Carlos; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-02-23

    Optical systems are described that have at least one source of a beam of blue light with divergence under 15.degree.. A phosphor emits yellow light when excited by the blue light. A collimator is disposed with the phosphor and forms a yellow beam with divergence under 15.degree.. A dichroic filter is positioned to transmit the beam of blue light to the phosphor and to reflect the beam of yellow light to an exit aperture. In different embodiments, the beams of blue and yellow light are incident upon said filter with central angles of 15.degree., 22.degree., and 45.degree.. The filter may reflect all of one polarization and part of the other polarization, and a polarization rotating retroreflector may then be provided to return the unreflected light to the filter.

  17. Governing through standards

    DEFF Research Database (Denmark)

    Brøgger, Katja

    2014-01-01

    This abstract adresses the ways in which new education standards have become integral to new modes of education governance. The paper explores the role of standards for accelerating the shift from national to transnational governance in higher education. Drawing on the case of higher education...... development in Scandinavia, the paper focuses on the unintended effects of the new international standards. The Bologna process was reframed and recontextualized in ways that undermined the very system it was set out to transform and govern....

  18. Information Security Standards

    OpenAIRE

    Dan Constantin Tofan

    2011-01-01

    The use of standards is unanimously accepted and gives the possibility of comparing a personal security system with a given frame of reference adopted at an international level. A good example is the ISO 9000 set of standards regarding the quality management system, which is a common reference regardless of the industry in which a certain company activates. Just like quality control standards for other industrial processes such as manufacturing and customer service, information security stand...

  19. Standard Model processes

    CERN Document Server

    Mangano, M.L.; Aguilar Saavedra, J.A.; Alekhin, S.; Badger, S.; Bauer, C.W.; Becher, T.; Bertone, V.; Bonvini, M.; Boselli, S.; Bothmann, E.; Boughezal, R.; Cacciari, M.; Carloni Calame, C.M.; Caola, F.; Campbell, J.M.; Carrazza, S.; Chiesa, M.; Cieri, L.; Cimaglia, F.; Febres Cordero, F.; Ferrarese, P.; D'Enterria, D.; Ferrera, G.; Garcia i Tormo, X.; Garzelli, M.V.; Germann, E.; Hirschi, V.; Han, T.; Ita, H.; Jäger, B.; Kallweit, S.; Karlberg, A.; Kuttimalai, S.; Krauss, F.; Larkoski, A.J.; Lindert, J.; Luisoni, G.; Maierhöfer, P.; Mattelaer, O.; Martinez, H.; Moch, S.; Montagna, G.; Moretti, M.; Nason, P.; Nicrosini, O.; Oleari, C.; Pagani, D.; Papaefstathiou, A.; Petriello, F.; Piccinini, F.; Pierini, M.; Pierog, T.; Pozzorini, S.; Re, E.; Robens, T.; Rojo, J.; Ruiz, R.; Sakurai, K.; Salam, G.P.; Salfelder, L.; Schönherr, M.; Schulze, M.; Schumann, S.; Selvaggi, M.; Shivaji, A.; Siodmok, A.; Skands, P.; Torrielli, P.; Tramontano, F.; Tsinikos, I.; Tweedie, B.; Vicini, A.; Westhoff, S.; Zaro, M.; Zeppenfeld, D.; CERN. Geneva. ATS Department

    2017-06-22

    This report summarises the properties of Standard Model processes at the 100 TeV pp collider. We document the production rates and typical distributions for a number of benchmark Standard Model processes, and discuss new dynamical phenomena arising at the highest energies available at this collider. We discuss the intrinsic physics interest in the measurement of these Standard Model processes, as well as their role as backgrounds for New Physics searches.

  20. Effect of soil temperature on optical frequency transfer through unidirectional dense-wavelength-division-multiplexing fiber-optic links.

    Science.gov (United States)

    Pinkert, T J; Böll, O; Willmann, L; Jansen, G S M; Dijck, E A; Groeneveld, B G H M; Smets, R; Bosveld, F C; Ubachs, W; Jungmann, K; Eikema, K S E; Koelemeij, J C J

    2015-02-01

    Results of optical frequency transfer over a carrier-grade dense-wavelength-division-multiplexing (DWDM) optical fiber network are presented. The relation between soil temperature changes on a buried optical fiber and frequency changes of an optical carrier through the fiber is modeled. Soil temperatures, measured at various depths by the Royal Netherlands Meteorology Institute (KNMI) are compared with observed frequency variations through this model. A comparison of a nine-day record of optical frequency measurements through the 2×298  km fiber link with soil temperature data shows qualitative agreement. A soil temperature model is used to predict the link stability over longer periods (days-months-years). We show that optical frequency dissemination is sufficiently stable to distribute and compare, e.g., rubidium frequency standards over standard DWDM optical fiber networks using unidirectional fibers.

  1. Standard NIM instrumentation system

    CERN Document Server

    1990-01-01

    NIM is a standard modular instrumentation system that is in wide use throughout the world. As the NIM system developed and accommodations were made to a dynamic instrumentation field and a rapidly advancing technology, additions, revisions and clarifications were made. These were incorporated into the standard in the form of addenda and errata. This standard is a revision of the NIM document, AEC Report TID- 20893 (Rev 4) dated July 1974. It includes all the addenda and errata items that were previously issued as well as numerous additional items to make the standard current with modern technology and manufacturing practice.

  2. Flight Standards Automation System -

    Data.gov (United States)

    Department of Transportation — FAVSIS supports Flight Standards Service (AFS) by maintaining their information on entities such as air carriers, air agencies, designated airmen, and check airmen....

  3. E-learning standards

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available E-learning standards refer to a system of common rules for content, authoring software and Learning Management Systems (LMSs - rules that specify how courses can be created and delivered over multiple platforms so that they all operate seamlessly together. Accredited standards ensure that the investment in time and intellectual capital could move from one system to the next. Currently, e-learning standards are being developed by four main organizations: AICC, IEEE, IMS, and ADL. The article presents some aspects of these standards.

  4. Highlights of China Standardization

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Environmental Management:Standards Guide Sustainable Transformation As of December 2010,more than 50,000 enterprises in China passed the ISO 14001 environment management system certification and more than 400 companies completed the voluntary accounting and authentication of carbon emissions.Environmental management system certification is a "green pass" in international trade.ISO has successively developed the ISO 14000 series environmental management standards and China has converted these standards into its national standards,which play a very important role in sustainable transformation and development of enterprises.

  5. Standardization of hormone determinations.

    Science.gov (United States)

    Stenman, Ulf-Håkan

    2013-12-01

    Standardization of hormone determinations is important because it simplifies interpretation of results and facilitates the use of common reference values for different assays. Progress in standardization has been achieved through the introduction of more homogeneous hormone standards for peptide and protein hormones. However, many automated methods for determinations of steroid hormones do not provide satisfactory result. Isotope dilution-mass spectrometry (ID-MS) has been used to establish reference methods for steroid hormone determinations and is now increasingly used for routine determinations of steroids and other low molecular weight compounds. Reference methods for protein hormones based on MS are being developed and these promise to improve standardization.

  6. Integration of active optical components

    Science.gov (United States)

    Wipiejewski, Torsten; Akulova, Yuliya A.; Fish, Gregory A.; Schow, Clint L.; Koh, Ping; Karim, Adil; Nakagawa, Shigeru; Dahl, Anders; Kozodoy, Peter; Matson, Alex; Short, Bradley W.; Turner, Chuck M.; Penniman, Steven; Larson, Michael C.; Coldren, Christopher W.; Coldren, Larry A.

    2003-06-01

    Integration of active optical components typically serves five goals: enhanced performance, smaller space, lower power dissipation, higher reliability, and lower cost. We are manufacturing widely tunable laser diodes with an integrated high speed electro absorption modulator for metro and all-optical switching applications. The monolithic integration combines the functions of high power laser light generation, wavelength tuning over the entire C-band, and high speed signal modulation in a single chip. The laser section of the chip contains two sampled grating DBRs with a gain and a phase section between them. The emission wavelength is tuned by current injection into the waveguide layers of the DBR and phase sections. The laser light passes through an integrated optical amplifier before reaching the modulator section on the chip. The amplifier boosts the cw output power of the laser and provides a convenient way of power leveling. The modulator is based on the Franz-Keldysh effect for a wide band of operation. The common waveguide through all sections minimizes optical coupling losses. The packaging of the monolithically integrated chip is much simpler compared to a discrete or hybrid solution using a laser chip, an SOA, and an external modulator. Since only one optical fiber coupling is required, the overall packaging cost of the transmitter module is largely reduced. Error free transmission at 2.5Gbit/s over 200km of standard single mode fiber is obtained with less than 1dB of dispersion penalty.

  7. Fiber optics engineering

    CERN Document Server

    Azadeh, Mohammad

    2009-01-01

    Covering fiber optics from an engineering perspective, this text emphasizes data conversion between electrical and optical domains. Techniques to improve the fidelity of this conversion (from electrical to optical domain, and vice versa) are also covered.

  8. Coding for optical channels

    CERN Document Server

    Djordjevic, Ivan; Vasic, Bane

    2010-01-01

    This unique book provides a coherent and comprehensive introduction to the fundamentals of optical communications, signal processing and coding for optical channels. It is the first to integrate the fundamentals of coding theory and optical communication.

  9. Quantum optics for experimentalists

    CERN Document Server

    Ou, Zhe-Yu Jeff

    2017-01-01

    This book on quantum optics is from the point of view of an experimentalist. It approaches the theory of quantum optics with the language of optical modes of classical wave theory, with which experimentalists are most familiar.

  10. Applied optics and optical design, part two

    CERN Document Server

    Conrady, A E

    2014-01-01

    Classic detailed treatment for practical designer. Fundamental concepts, systematic study and design of all types of optical systems. Reader can then design simpler optical systems without aid. Part Two of Two.

  11. Tunable laser optics

    CERN Document Server

    Duarte, FJ

    2015-01-01

    This Second Edition of a bestselling book describes the optics and optical principles needed to build lasers. It also highlights the optics instrumentation necessary to characterize laser emissions and focuses on laser-based optical instrumentation. The book emphasizes practical and utilitarian aspects of relevant optics including the essential theory. This revised, expanded, and improved edition contains new material on tunable lasers and discusses relevant topics in quantum optics.

  12. Quantum Modelling of Electro-Optic Modulators

    CERN Document Server

    Capmany, Jose

    2011-01-01

    Many components that are employed in quantum information and communication systems are well known photonic devices encountered in standard optical fiber communication systems, such as optical beamsplitters, waveguide couplers and junctions, electro-optic modulators and optical fiber links. The use of these photonic devices is becoming increasingly important especially in the context of their possible integration either in a specifically designed system or in an already deployed end-to-end fiber link. Whereas the behavior of these devices is well known under the classical regime, in some cases their operation under quantum conditions is less well understood. This paper reviews the salient features of the quantum scattering theory describing both the operation of the electro-optic phase and amplitude modulators in discrete and continuous-mode formalisms. This subject is timely and of importance in light of the increasing utilization of these devices in a variety of systems, including quantum key distribution an...

  13. Standardizing visual display quality

    NARCIS (Netherlands)

    Besuijen, Ko; Spenkelink, Gerd P.J.

    1998-01-01

    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

  14. Soviet Standardization of Russian.

    Science.gov (United States)

    Benson, Morton

    1961-01-01

    After a brief history of influences on the standardization of Russian since the Revolution, the descriptive and normalizing role of specific reference works of grammar, phonetics, vocabulary, and morphology is discussed. Concluding remarks point out a problem caused by a lack of coordination of standardization efforts and the mounting demands for…

  15. State Skill Standards: Photography

    Science.gov (United States)

    Howell, Frederick; Reed, Loretta; Jensen, Capra; Robison, Gary; Taylor, Susan; Pavesich, Christine

    2007-01-01

    The Department of Education has undertaken an ambitious effort to develop statewide skill standards for all content areas in career and technical education. The standards in this document are for photography programs and are designed to clearly state what the student should know and be able to do upon completion of an advanced high-school program.…

  16. How many standards?

    DEFF Research Database (Denmark)

    Maegaard, Marie

    2009-01-01

    Discussions of standardisation and standard languages has a long history in linguistics. Tore Kristiansen has contributed to these discussions in various ways, and in this chapter I will focus on his claim that young Danes operate with two standards, one for the media and one for the school. This...

  17. Why Standards Matter

    Science.gov (United States)

    Anthony, Michael A.; Caleb, Derry; Mitchell, Stanley G.

    2012-01-01

    When standards are absent, people soon notice. They care when products turn out to be of poor quality, are unreliable, or dangerous because of counterfeiting. By positioning their products in relation to a common standard, firms grow the total size of the market, and can focus their innovation efforts in areas where they have a comparative…

  18. Weston Standard battery

    CERN Multimedia

    This is a Weston AOIP standard battery with its calibration certificate (1956). Inside, the glassware forms an "H". Its name comes from the British physicist Edward Weston. A standard is the materialization of a given quantity whose value is known with great accuracy.

  19. [CAS General Standards 2012

    Science.gov (United States)

    Council for the Advancement of Standards in Higher Education, 2011

    2011-01-01

    The mission of the Council for the Advancement of Standards in Higher Education (CAS) is to promote the improvement of programs and services to enhance the quality of student learning and development. CAS is a consortium of professional associations who work collaboratively to develop and promulgate standards and guidelines and to encourage…

  20. Workflow automation architecture standard

    Energy Technology Data Exchange (ETDEWEB)

    Moshofsky, R.P.; Rohen, W.T. [Boeing Computer Services Co., Richland, WA (United States)

    1994-11-14

    This document presents an architectural standard for application of workflow automation technology. The standard includes a functional architecture, process for developing an automated workflow system for a work group, functional and collateral specifications for workflow automation, and results of a proof of concept prototype.

  1. Academic Standards in Alabama

    Science.gov (United States)

    A+ Education Partnership, 2014

    2014-01-01

    Education policymakers and educators in Alabama are committed to improving the state's public education system to ensure that students gain the knowledge and skills they need to graduate from high school ready for real life. The state is on the path to implementing higher academic standards--the College and Career Ready Standards--which lay a…

  2. Intelligent Optics Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Intelligent Optics Laboratory supports sophisticated investigations on adaptive and nonlinear optics; advancedimaging and image processing; ground-to-ground and...

  3. Fibre-optic communications

    CERN Document Server

    Lecoy, Pierre

    2010-01-01

    This book describes in a comprehensive manner the components and systems of fiber optic communications and networks. The first section explains the theory of multimode and single-mode fibers, then the technological features, including manufacturing, cabling, and connecting. The second section describes the various components (passive and active optical components, integrated optics, opto-electronic transmitters and receivers, and optical amplifiers) used in fiber optic systems. Finally, the optical transmission system design is explained, and applications to optical networks and fiber optic se

  4. Optical Remote Sensing Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Optical Remote Sensing Laboratory deploys rugged, cutting-edge electro-optical instrumentation for the collection of various event signatures, with expertise in...

  5. Investigation of Optical Fibers for Nonlinear Optics.

    Science.gov (United States)

    1984-04-17

    Northwestern University, 1970. Experience Dr. Harrington has 13 years of research experi- ence in the area of optical properties of solids . Since joining...dynamics, and optical properties of solids . 34 34I ANTONIO C. PASTOR, Member of the Technical Staff, Optical Physics Department, Hughes Research

  6. Ultracold atoms and precise time standards.

    Science.gov (United States)

    Campbell, Gretchen K; Phillips, William D

    2011-10-28

    Experimental techniques of laser cooling and trapping, along with other cooling techniques, have produced gaseous samples of atoms so cold that they are, for many practical purposes, in the quantum ground state of their centre-of-mass motion. Such low velocities have virtually eliminated effects such as Doppler shifts, relativistic time dilation and observation-time broadening that previously limited the performance of atomic frequency standards. Today, the best laser-cooled, caesium atomic fountain, microwave frequency standards realize the International System of Units (SI) definition of the second to a relative accuracy of ≈3×10(-16). Optical frequency standards, which do not realize the SI second, have even better performance: cold neutral atoms trapped in optical lattices now yield relative systematic uncertainties of ≈1×10(-16), whereas cold-trapped ions have systematic uncertainties of 9×10(-18). We will discuss the current limitations in the performance of neutral atom atomic frequency standards and prospects for the future.

  7. Evaluating Living Standard Indicators

    Directory of Open Access Journals (Sweden)

    Birčiaková Naďa

    2015-09-01

    Full Text Available This paper deals with the evaluation of selected available indicators of living standards, divided into three groups, namely economic, environmental, and social. We have selected six countries of the European Union for analysis: Bulgaria, the Czech Republic, Hungary, Luxembourg, France, and Great Britain. The aim of this paper is to evaluate indicators measuring living standards and suggest the most important factors which should be included in the final measurement. We have tried to determine what factors influence each indicator and what factors affect living standards. We have chosen regression analysis as our main method. From the study of factors, we can deduce their impact on living standards, and thus the value of indicators of living standards. Indicators with a high degree of reliability include the following factors: size and density of population, health care and spending on education. Emissions of carbon dioxide in the atmosphere also have a certain lower degree of reliability.

  8. Fibre optic power meter calibration uncertainties

    CSIR Research Space (South Africa)

    Nel, M

    2010-06-01

    Full Text Available thereof. It was done only for standard single mode fibre with FC (ferrule connector) connectors, and using a 1310 and a 1550 nm Fabry Perot laser (FP laser). The calibration set-up and procedure The uncertainty contributions for fibre optic power..., in this case 1310 or 1550 nm, is fed to the fibre optic power meter (secondary standard or unit under test (UUT)) via an attenuator. The attenuator serves to reduce back-reflections into the source and to set the power to the desired level. In Fig. 1...

  9. Illusion optics

    Science.gov (United States)

    Lai, Yun; Ng, Jack; Chen, Huan-Yang; Zhang, Zhao-Qing; Chan, C. T.

    2010-09-01

    The technique of “transformation optics” establishes a correspondence between coordinate transformation and material constitutive parameters. Most of the transformation optics mappings give metamaterials that have graded positive refractive indices that can steer light in curves defined by the coordinate transformation. We will focus on those “folded-geometry mappings” that give negative refractive index materials that have special wave scattering properties. One interesting example is a kind of remote illusion device that can transform the stereoscopic image of an object into the illusion of some other object of our choice. The conceptual device can create the illusion without touching or encircling the object. For any incident wave, the device transforms the scattered waves of the original object into that of the object chosen for illusion outside a virtual boundary. We will illustrate some possible applications of this type of metamaterial remote device, including “cloaking at a distance,” partial cloaking, cloaking from an embedded device, revealing a hidden object inside a container, turning the image of one object into that of another object, and seeing through a wall. The feasibility of building this remote illusion device by metamaterials will also be discussed.

  10. Light Optics for Optical Stochastic Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Andorf, Matthew [NICADD, DeKalb; Lebedev, Valeri [Fermilab; Piot, Philippe [NICADD, DeKalb; Ruan, Jinhao [Fermilab

    2016-06-01

    In Optical Stochastic Cooling (OSC) radiation generated by a particle in a "pickup" undulator is amplified and transported to a downstream "kicker" undulator where it interacts with the same particle which radiated it. Fermilab plans to carry out both passive (no optical amplifier) and active (optical amplifier) tests of OSC at the Integrable Optics Test Accelerator (IOTA) currently in construction*. The performace of the optical system is analyzed with simulations in Synchrotron Radiation Workshop (SRW) accounting for the specific temporal and spectral properties of undulator radiation and being augmented to include dispersion of lens material.

  11. 76 FR 75782 - Revising Standards Referenced in the Acetylene Standard

    Science.gov (United States)

    2011-12-05

    ... the Acetylene Standard AGENCY: Occupational Safety and Health Administration (OSHA), Department of... is revising its Acetylene Standard for general industry by updating a reference to a standard... and Explanation of Revisions to the Acetylene Standard IV. Procedural Determinations A....

  12. Visual display requirements: on standards and their users

    Science.gov (United States)

    van Nes, Floris L.

    2005-01-01

    A new ISO standard for visual displays: "Ergonomic requirements and measurement techniques for electronic visual displays" is soon to be released as a Draft International Standard. The core of the new standard is the part with generic ergonomic requirements for visual displays. Three parts of the standard describe three types of measurements: electro-optical ones, to be used in general; user performance test methods, for innovative displays for which no electro-optical methods exist; and field assessment methods, to be used outside of the laboratory, under the conditions of use at the workplace. The last part of the standard describes five compliance routes and procedures for five different display technologies and contexts of use. A number of choices and problems that standard writers have to face are mentioned. Should a visual display standard be written primarily for young users, with mostly a high visual acuity and in possession of their full accommodative power, wanting to use tiny hand-held displays featuring very small characters ? Or should the standard be focused on the elderly, with their reduction in visual faculties, barring the use of small characters that may irritate or disable such older users ? The question how to put human factors principles in standards sometimes seems a battle between idealists and realists. It therefore is important to strike a balance between different attitudes, backgrounds and interests in a standards writing committee - as indeed happens in ISO/TC 159/SC 4/WG 2, "Visual Display Requirements". The author is convener of this Working Group.

  13. FDA Recognized Consensus Standards

    Data.gov (United States)

    U.S. Department of Health & Human Services — This database consists of those national and international standards recognized by FDA which manufacturers can declare conformity to and is part of the information...

  14. Striving for "Standard Economy"

    Institute of Scientific and Technical Information of China (English)

    Li Huailin

    2006-01-01

    @@ Promotion of the "standard economy" itself is an integral part of upgrading the quality of China's economic development, transforming economic growth mode and responding to foreign trade barriers as well as a key strategy for improving foreign trade level.

  15. FREIGHT CONTAINER LIFTING STANDARD

    Energy Technology Data Exchange (ETDEWEB)

    POWERS DJ; SCOTT MA; MACKEY TC

    2010-01-13

    This standard details the correct methods of lifting and handling Series 1 freight containers following ISO-3874 and ISO-1496. The changes within RPP-40736 will allow better reading comprehension, as well as correcting editorial errors.

  16. 1990 Fischer Standard study

    Energy Technology Data Exchange (ETDEWEB)

    Roubik, G.J.

    1990-09-12

    The purpose of this work is to develop a set of Titanium areal density standards for calibration and maintenance of the Fischer`s X-ray Fluorescence measurement system characterization curve program. The electron microprobe was calibrated for Titanium films on ceramic substrates using an existing set of laboratory standards (Quantity: 6 Range: 0.310 to 1.605). Fourteen source assemblies were measured and assigned values. These values are based on a mean calculation, of five separate readings, from best curve fit equations developed form the plot of the laboratory standards areal density (Source Measure) versus electron microprobe measurement (reading). The best fit equations were determined using the SAS General Linear Modeling (GLM) procedure. Four separate best fit equations were evaluated (Linear, Quadratic, Cubic and Exponential). Areal density values for the Fischer Standards appear here ordered by best fit equation based on maximum R{sup 2}.

  17. The Standard Cosmological Model

    CERN Document Server

    Scott, D

    2005-01-01

    The Standard Model of Particle Physics (SMPP) is an enormously successful description of high energy physics, driving ever more precise measurements to find "physics beyond the standard model", as well as providing motivation for developing more fundamental ideas that might explain the values of its parameters. Simultaneously, a description of the entire 3-dimensional structure of the present-day Universe is being built up painstakingly. Most of the structure is stochastic in nature, being merely the result of the particular realisation of the "initial conditions" within our observable Universe patch. However, governing this structure is the Standard Model of Cosmology (SMC), which appears to require only about a dozen parameters. Cosmologists are now determining the values of these quantities with increasing precision in order to search for "physics beyond the standard model", as well as trying to develop an understanding of the more fundamental ideas which might explain the values of its parameters. Althoug...

  18. AKRO: Standard Prices

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard prices are generated for cost recovery programs in the Individual Fishing Quota (IFQ) halibut and sablefish, BSAI Rationalized crab, and Central Gulf of...

  19. Ozone Standard Reference Photometer

    Data.gov (United States)

    Federal Laboratory Consortium — The Standard Reference Photometer (SRP) Program began in the early 1980s as collaboration between NIST and the U.S. Environmental Protection Agency (EPA) to design,...

  20. Crew Transportation Operations Standards

    Science.gov (United States)

    Mango, Edward J.; Pearson, Don J. (Compiler)

    2013-01-01

    The Crew Transportation Operations Standards contains descriptions of ground and flight operations processes and specifications and the criteria which will be used to evaluate the acceptability of Commercial Providers' proposed processes and specifications.

  1. International standards in metallurgy

    Institute of Scientific and Technical Information of China (English)

    Fomina; O.; N.

    2005-01-01

    The existence of incompatible standards in many technical fields represents a technical barrier to international cooperation between enterprises in different countries in the manufacture of high technology products.……

  2. Transformation optics and metamaterials

    Science.gov (United States)

    Chen, Huanyang; Chan, C. T.; Sheng, Ping

    2010-05-01

    Underpinned by the advent of metamaterials, transformation optics offers great versatility for controlling electromagnetic waves to create materials with specially designed properties. Here we review the potential of transformation optics to create functionalities in which the optical properties can be designed almost at will. This approach can be used to engineer various optical illusion effects, such as the invisibility cloak.

  3. Optical image encryption topology.

    Science.gov (United States)

    Yong-Liang, Xiao; Xin, Zhou; Qiong-Hua, Wang; Sheng, Yuan; Yao-Yao, Chen

    2009-10-15

    Optical image encryption topology is proposed based on the principle of random-phase encoding. Various encryption topological units, involving peer-to-peer, ring, star, and tree topologies, can be realized by an optical 6f system. These topological units can be interconnected to constitute an optical image encryption network. The encryption and decryption can be performed in both digital and optical methods.

  4. Introduction to ocean optics

    Science.gov (United States)

    Gordon, H. R.; Smith, R. C.; Zaneveld, J. R. V.

    1984-01-01

    In this introductory survey of optical oceanography, the fundamental inherent and apparent optical properties of natural waters are presented. Relationships between these inherent and apparent optical properties, as related through the radiative transfer equation, are then examined. Following the first three theoretical sections, brief discussions describing the application of ocean optics to geophysics, biological oceanography, and ocean remote sensing are then presented.

  5. Axial Optical Traps: A New Direction for Optical Tweezers.

    Science.gov (United States)

    Yehoshua, Samuel; Pollari, Russell; Milstein, Joshua N

    2015-06-16

    Optical tweezers have revolutionized our understanding of the microscopic world. Axial optical tweezers, which apply force to a surface-tethered molecule by directly moving either the trap or the stage along the laser beam axis, offer several potential benefits when studying a range of novel biophysical phenomena. This geometry, although it is conceptually straightforward, suffers from aberrations that result in variation of the trap stiffness when the distance between the microscope coverslip and the trap focus is being changed. Many standard techniques, such as back-focal-plane interferometry, are difficult to employ in this geometry due to back-scattered light between the bead and the coverslip, whereas the noise inherent in a surface-tethered assay can severely limit the resolution of an experiment. Because of these complications, precision force spectroscopy measurements have adapted alternative geometries such as the highly successful dumbbell traps. In recent years, however, most of the difficulties inherent in constructing a precision axial optical tweezers have been solved. This review article aims to inform the reader about recent progress in axial optical trapping, as well as the potential for these devices to perform innovative biophysical measurements. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  6. Portable fiber-optic taper coupled optical microscopy platform

    Science.gov (United States)

    Wang, Weiming; Yu, Yan; Huang, Hui; Ou, Jinping

    2017-04-01

    The optical fiber taper coupled with CMOS has advantages of high sensitivity, compact structure and low distortion in the imaging platform. So it is widely used in low light, high speed and X-ray imaging systems. In the meanwhile, the peculiarity of the coupled structure can meet the needs of the demand in microscopy imaging. Toward this end, we developed a microscopic imaging platform based on the coupling of cellphone camera module and fiber optic taper for the measurement of the human blood samples and ascaris lumbricoides. The platform, weighing 70 grams, is based on the existing camera module of the smartphone and a fiber-optic array which providing a magnification factor of 6x.The top facet of the taper, on which samples are placed, serves as an irregular sampling grid for contact imaging. The magnified images of the sample, located on the bottom facet of the fiber, are then projected onto the CMOS sensor. This paper introduces the portable medical imaging system based on the optical fiber coupling with CMOS, and theoretically analyzes the feasibility of the system. The image data and process results either can be stored on the memory or transmitted to the remote medical institutions for the telemedicine. We validate the performance of this cell-phone based microscopy platform using human blood samples and test target, achieving comparable results to a standard bench-top microscope.

  7. Food Safety & Standards

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ An increasing number of people have realized that food safety is an important issue for public health. It not only concerns public health and safety, but also has direct influence on national economic progress and social development. The development and implementation of food safety standards play a vital role in protecting public health, as well as in standardizing and facilitating the sound development of food production and business.

  8. The Gold Standard Programme

    DEFF Research Database (Denmark)

    Neumann, Tim; Rasmussen, Mette; Ghith, Nermin

    2013-01-01

    To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates.......To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates....

  9. Standardization Today and Tomorrow

    Science.gov (United States)

    1998-05-01

    Order for the Whole World) Eberstein, H.-H.: Sicherheitstechnisches Recht und Normen ; in: Peters. 0. H. u. A. Meyna: Handbuch der Si- cherheitstechnik...on the Protection of Labor for the Development and Design Sector) Landis, J. W.: Freie Welt - freier Handel - freie Normen ; in: DIN-Mitteilungen 57...Norm auf die Vielfalt effect of company standard on variety KonformitAt zu nationalen Normen conformity to national standards Konformit6t zu

  10. Standardization Practices of Gree

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    1.The great importance attached by the company's executives is a strong guarantee for leap-forward development of standardization.To give play to the strategic role of standards in supporting the long-term and sustainable development of the enterprise,the company's management has attached great importance to the standardization work and provided strong capital support and guarantee of resources in standardization.Continuously improve the requirements of corporate technical standards and reliability quality control means,develop core technologies with independent intellectual property rights,continuously achieve major breakthroughs in key technologies and successfully apply to the company's products to help the enterprises maintain rapid and steady development in the market of household electrical appliances with extremely intense competition,achieve remarkable economic and social benefits for the company,and provide strong support for leap-forward development of standardization work.The company has successively and independently developed a series of highend products and technologies which are intemationally advanced.So far,the company has 10 innovations included in the national science and technology programs.

  11. Nonlinear Optical Rectennas

    CERN Document Server

    Stolz, A; Markey, L; Francs, G Colas des; Bouhelier, A

    2013-01-01

    We introduce strongly-coupled optical gap antennas to interface optical radiation with current-carrying electrons at the nanoscale. The transducer relies on the nonlinear optical and electrical properties of an optical antenna operating in the tunneling regime. We discuss the underlying physical mechanisms controlling the conversion and demonstrate that a two-wire optical antenna can provide advanced optoelectronic functionalities beyond tailoring the electromagnetic response of a single emitter. Interfacing an electronic command layer with a nanoscale optical device may thus be facilitated by the optical rectennas discussed here.

  12. Optics for dummies

    CERN Document Server

    Duree, Galen C

    2011-01-01

    The easy way to shed light on Optics In general terms, optics is the science of light. More specifically, optics is a branch of physics that describes the behavior and properties of light?including visible, infrared, and ultraviolet?and the interaction of light with matter. Optics For Dummies gives you an approachable introduction to optical science, methods, and applications. You'll get plain-English explanations of the nature of light and optical effects; reflection, refraction, and diffraction; color dispersion; optical devices, industrial, medical, and military applicatio

  13. [Hereditary optic neuropathies].

    Science.gov (United States)

    Milea, D; Verny, C

    2012-10-01

    Hereditary optic neuropathies are a group of heterogeneous conditions affecting both optic nerves, with an autosomal dominant, autosomal recessive, X-related or mitochondrial transmission. The two most common non-syndromic hereditary optic neuropathies (Leber's hereditary optic neuropathy and autosomal dominant optic atrophy) are very different in their clinical presentation and their genetic transmission, leading however to a common, non-specific optic nerve atrophy. Beyond the optic atrophy-related visual loss, which is the clinical hallmark of this group of diseases, other associated neurological signs are increasingly recognized.

  14. DOE technical standards list. Department of Energy standards index

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This document was prepared for use by personnel involved in the selection and use of DOE technical standards and other Government and non-Government standards. This TSL provides listing of current DOE technical standards, non-Government standards that have been adopted by DOE, other Government documents in which DOE has a recorded interest, and canceled DOE technical standards. Information on new DOE technical standards projects, technical standards released for coordination, recently published DOE technical standards, and activities of non-Government standards bodies that may be of interest to DOE is published monthly in Standards Actions.

  15. Principles of adaptive optics

    CERN Document Server

    Tyson, Robert

    2010-01-01

    History and BackgroundIntroductionHistoryPhysical OpticsTerms in Adaptive OpticsSources of AberrationsAtmospheric TurbulenceThermal BloomingNonatmospheric SourcesAdaptive Optics CompensationPhase ConjugationLimitations of Phase ConjugationArtificial Guide StarsLasers for Guide StarsCombining the LimitationsLinear AnalysisPartial Phase ConjugationAdaptive Optics SystemsAdaptive Optics Imaging SystemsBeam Propagation Syst

  16. Optical imaging and spectroscopy

    CERN Document Server

    Brady, David J

    2009-01-01

    An essential reference for optical sensor system design This is the first text to present an integrated view of the optical and mathematical analysis tools necessary to understand computational optical system design. It presents the foundations of computational optical sensor design with a focus entirely on digital imaging and spectroscopy. It systematically covers: Coded aperture and tomographic imaging Sampling and transformations in optical systems, including wavelets and generalized sampling techniques essential to digital system analysis Geometric, wave, and statis

  17. Digitalization optical open loop test system for fiber optic gyroscope

    Institute of Scientific and Technical Information of China (English)

    ZHANG Deng-wei; SHU Xiao-wu; MU Xu-dong; LIU Cheng

    2006-01-01

    In order to receive and process the open loop signal from fiber optic gyroscopes speedily,stably and expediently,and to realize the amity interface between human and machine,a digital system that can convert GPIB (general purpose interface bus ) parallel bus into Universal Serial Bus is developed.All the interface functions of GP1B and the hardware system are realized through FPGA.With a digital sampling and processing system designed with VC++ in Windows platform,the real-time controlling procedure,high-speed receiving and sending data can be carried out,and the results can be displayed too.So the design of the system is flexible,the reliability and the stability are improved,error rate is no more than 10-11,the highest bit rate is 8 MB/s and the open loop detection system for optic fiber gyros achieves standardization and complete digitalization simultaneously.

  18. Low concentrator PV optics optimization

    Science.gov (United States)

    Sharp, Leonard; Chang, Ben

    2008-08-01

    Purpose: Cost reduction is a major focus of the solar industry. Thin film technologies and concentration systems are viable ways to reducing cost, with unique strengths and weakness for both. Most of the concentrating PV work focuses on high concentration systems for reducing energy cost. Meanwhile, many believe that low concentrators provide significant cost reduction potential while addressing the mainstream PV market with a product that acts as a flat panel replacement. This paper analyzes the relative benefit of asymmetric vs. symmetric optics for low-concentrators in light of specific PV applications. Approach: Symmetric and asymmetric concentrating PV module performance is evaluated using computer simulation to determine potential value across various geographic locations and applications. The selected optic design is modeled against standard cSi flat panels and thin film to determine application fit, system level energy density and economic value. Results: While symmetric designs may seem ideal, asymmetric designs have an advantage in energy density. Both designs are assessed for aperture, optimum concentration ratio, and ideal system array configuration. Analysis of performance across climate specific effects (diffuse, direct and circumsolar) and location specific effects (sunpath) are also presented. The energy density and energy production of low concentrators provide a compelling value proposition. More significantly, the choice of optics for a low concentrating design can affect real world performance. With the goal of maximizing energy density and return on investment, this paper presents the advantages of asymmetric optic concentration and illustrates the value of this design within specific PV applications.

  19. The power of fiber optics

    Energy Technology Data Exchange (ETDEWEB)

    Roy, C.

    1999-03-01

    The latest technology in optical groundwire (OPGW), involving a single cable serving as a communications network, providing high-speed data and voice transmission, and as a conventional groundwire, part of a power transmission grid, is described. The first-ever symposium devoted to OPGW was held at Hydro-Quebec`s IREQ facility in Montreal, a fitting venue, considering that Hydro-Quebec has installed an extensive network of some 3,500 km of OPGW cables since 1992. The international symposium was attended by over 130 interested experts mainly from North America, but with delegates as far away as Australia, Japan, Libya, Brazil and the UK. The three-day event showcased a number of presentations and demonstrations concerning OPGW splicing requirements, the live-line installation process, the merits of using fiber optics in a power situation, comparison of international standards in OPGW and fiber optics applications, and future developments in fiber optics technology. Demonstration of IREQ`s OPGW type-testing and manufacturer`s exhibits provided an opportunity for hands-on experience.

  20. DOE technical standards list: Department of Energy standards index

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    This Department of Energy (DOE) technical standards list (TSL) has been prepared by the Office of Nuclear Safety Policy and Standards (EH-31) on the basis of currently available technical information. Periodic updates of this TSL will be issued as additional information is received on standardization documents being issued, adopted, or canceled by DOE. This document was prepared for use by personnel involved in the selection and use of DOE technical standards and other Government and non-Government standards. This TSL provides listings of current DOE technical standards, non-Government standards that have been adopted by DOE, other standards-related documents in which DOE has a recorded interest, and canceled DOE technical standards. Information on new DOE technical standards projects, technical standards released for coordination, recently published DOE technical standards, and activities of non-Government standards bodies that may be of interest to DOE is published monthly in Standards Actions.

  1. Fiber Optic-Based Refractive Index Sensing at INESC Porto

    Science.gov (United States)

    Jorge, Pedro A. S.; Silva, Susana O.; Gouveia, Carlos; Tafulo, Paula; Coelho, Luis; Caldas, Paulo; Viegas, Diana; Rego, Gaspar; Baptista, José M.; Santos, José L.; Frazão, Orlando

    2012-01-01

    A review of refractive index measurement based on different types of optical fiber sensor configurations and techniques is presented. It addresses the main developments in the area, with particular focus on results obtained at INESC Porto, Portugal. The optical fiber sensing structures studied include those based on Bragg and long period gratings, on micro-interferometers, on plasmonic effects in fibers and on multimode interference in a large spectrum of standard and microstructured optical fibers. PMID:22969405

  2. Nonlinear optical properties of Au/PVP composite thin films

    Institute of Scientific and Technical Information of China (English)

    Shen Hong; Cheng Bo-Lin; Lu Guo-Wei; Wang Wei-Tian; Guan Dong-Yi; Chen Zheng-Hao; Yang Guo-Zhen

    2005-01-01

    Colloidal Au and poly(vinylpyrrolidone) (PVP) composite thin films are fabricated by spin-coating method. Linear optical absorption measurements of the Au/PVP composite films indicate an absorption peak around 530 nm due to the surface plasmon resonance of gold nanoparticles. Nonlinear optical properties are studied using standard Z-scan technique, and experimental results show large optical nonlinearities of the Au/PVP composite films. A large value of films.

  3. Optimizing multimedia content delivery over next-generation optical networks

    OpenAIRE

    Di Pascale, Emanuele

    2015-01-01

    This thesis analyzes the performance of a Peer-to-Peer (P2P) multimedia content delivery system for a network architecture based on next-generation Passive Optical Networks (PONs). A PON is an optical access technology that is able to deliver high bandwidth capacities at a fraction of the cost of traditional point-to-point fiber solutions; this is achieved by sharing the same feeder fiber among several customers through the use of optical splitters. Established standards such as G...

  4. Non Contact Optical Ultrasound Concept for Biomedical Imaging

    Science.gov (United States)

    2016-11-03

    in rigid biological tissue such as bone that are well described in the seismological literature [] while compressional waves dominate in biomass ...potential to operate within skin and eye safety standards. 8. Advantages and disadvantages of optical laser ultrasound compared to contact...location may help to mitigate or reduce these sources of noise. Limitations in photoacoustic excitation also present disadvantages for an optical

  5. Optical gateway for intelligent buildings: a new open-up window to the optical fibre sensors market?

    Science.gov (United States)

    Fernandez-Valdivielso, Carlos; Matias, Ignacio R.; Arregui, Francisco J.; Bariain, Candido; Lopez-Amo, Manuel

    2004-06-01

    This paper presents the first optical fiber sensor gateway for integrating these special measurement devices in Home Automation Systems, concretely in those buildings that use the KNX European Intelligent Buildings Standard.

  6. 78 FR 51463 - Energy Conservation Program: Energy Conservation Standards for Metal Halide Lamp Fixtures

    Science.gov (United States)

    2013-08-20

    .... Introduction A. Authority B. Background 1. Current Standards 2. History of Standards Rulemaking for Metal...--Lamp, Ballast, Optics, and Enclosure 3. California Title 20 Approach C. Combined Rulemakings D. Standby... some combination of level(s) that incorporate the proposed standards in part. II. Introduction The...

  7. Design of optical switches by illusion optics

    Science.gov (United States)

    Shoorian, H. R.; Abrishamian, M. S.

    2013-05-01

    In this paper, illusion optics theory is employed to form Bragg gratings in an optical waveguide in order to design an optical switch. By using an illusion device at a certain distance from the waveguide, the effective refractive index of the waveguide is remotely modulated, turning the waveguide into a distributed Bragg reflector (DBR) which blocks the waves at a stop band. By removing the illusion device, the waves propagate through the waveguide again. In addition, this method is used to remotely tune DBR optical properties such as resonant frequency and bandwidth in a wide range, which leads to a tunable filter for optical switching applications. Finally, using an illusion device at a distance, an optical cavity is created by inserting defects remotely in a DBR without any physical damage in the primary device.

  8. Consequences of Accounting Standards

    Institute of Scientific and Technical Information of China (English)

    Cai Mingyue

    2009-01-01

    The first part of this article consists in attempting to highlight the importance of concerning about the economic consequences and introducing the foundation of economic consequence theory, proposing that the accounting standard is not only a kind of technical standard, it also has the economic consequences, so it becomes the object which all quarters special interest group gambles to get latent profit. After general characterization of the economic consequences in the second part, the article gives a description of the influences the change of accounting standards bring to the government, the ordinary investors and creditors, the auditors, and the enterprise, establishing a framework that how those groups react as the economic consequences in the third part. The fourth section compare technical theory and accounting standards theory, links the basic norms of accounting such as conservatism, relevance and reliability to the methods of escaping the harm of economic consequences, then proposes some specific methods in the formuhtion of accounting standard. Finally, the article utilizes the methods to settle the problems appearing in Chinese market.

  9. Product evaluation and standardization.

    Science.gov (United States)

    Fry, M

    1986-01-01

    Although it was cumbersome at the time of implementation, the process began to operate effectively once hospital personnel overcame their initial concern over a potential "paperwork jungle" and realized that the paperwork is easy to control. When implementing such a system, it is vital that all personnel make a commitment to the process. Although it can be time-consuming and demanding in that employees must attend meetings, write standards, conduct and coordinate evaluations, the benefits are paid back many times over, both in dollars and staff satisfaction. A major plus of our system is our requirement that the user justify why a product is needed. That need is explained in the content of a product standard. The demerit rating system, while not a precise mathematical science, does indicate the relative importance of each criterion. The final result is a standard product, a standard process and a standard decision, against which both product and process performance can be measured. This measurement is a level of professionalism achieved by the actions of a motivated staff, working in cooperation toward a single goal.

  10. Wavefront sensing reveals optical coherence.

    Science.gov (United States)

    Stoklasa, B; Motka, L; Rehacek, J; Hradil, Z; Sánchez-Soto, L L

    2014-01-01

    Wavefront sensing is a set of techniques providing efficient means to ascertain the shape of an optical wavefront or its deviation from an ideal reference. Owing to its wide dynamical range and high optical efficiency, the Shack-Hartmann wavefront sensor is nowadays the most widely used of these sensors. Here we show that it actually performs a simultaneous measurement of position and angular spectrum of the incident radiation and, therefore, when combined with tomographic techniques previously developed for quantum information processing, the Shack-Hartmann wavefront sensor can be instrumental in reconstructing the complete coherence properties of the signal. We confirm these predictions with an experimental characterization of partially coherent vortex beams, a case that cannot be treated with the standard tools. This seems to indicate that classical methods employed hitherto do not fully exploit the potential of the registered data.

  11. Using turbocodes on optical links

    Directory of Open Access Journals (Sweden)

    Glenn Claes

    2006-04-01

    Full Text Available The fast evolving telecommunication world is permanently in search for faster and better communication links. On one hand, turbo codes are like a dream come true. Due to their amazing performance, they have become the reference in the word of error detecting and correcting codes. On the other hand, broadband transmission channels like optical fibres can meet the need for higher transmission velocity. In this paper therefore we will bring these two elements together and thus the performance of turbocodes on optical links will be studied. First the turbocode will be optimised throughout an individual analysis of each of its design parameters. Moreover it wil be shown that turbocodes have much better performance than the well known Reed-Solomon codes. Finally we will show that the 8Bit/10Bit code, which is required to comply with the Gigabit Ethernet standard, becomes superfluous when working with turbocodes. All tests were carried out on multimode graded-index glass fibres.

  12. Radium single-ion optical clock

    NARCIS (Netherlands)

    Versolato, O. O.; Wansbeek, L. W.; Jungmann, K.; Timmermans, R. G. E.; Willmann, L.; Wilschut, H. W.

    2011-01-01

    We explore the potential of the electric quadrupole transitions $7s\\,^2S_{1/2}$ - $6d\\,^2D_{3/2}$, $6d\\,^2D_{5/2}$ in radium isotopes as single-ion optical frequency standards. The frequency shifts of the clock transitions due to external fields and the corresponding uncertainties are calculated.

  13. IOT Overview: Optical Multi-Object Spectrographs

    Science.gov (United States)

    Schmidtobreick, L.; Bagnulo, S.; Jehin, E.; Marconi, G.; O'Brien, K.; Pompei, E.; Saviane, I.

    We give an introduction to the several instruments that ESO operates and which are able to perform optical multi-object spectroscopy. We point out the standard ways of reducing these spectra, the problems that occur, and the way we deal with them. A short introduction is given on how the quality control is performed.

  14. Automated Standard Hazard Tool

    Science.gov (United States)

    Stebler, Shane

    2014-01-01

    The current system used to generate standard hazard reports is considered cumbersome and iterative. This study defines a structure for this system's process in a clear, algorithmic way so that standard hazard reports and basic hazard analysis may be completed using a centralized, web-based computer application. To accomplish this task, a test server is used to host a prototype of the tool during development. The prototype is configured to easily integrate into NASA's current server systems with minimal alteration. Additionally, the tool is easily updated and provides NASA with a system that may grow to accommodate future requirements and possibly, different applications. Results of this project's success are outlined in positive, subjective reviews complete by payload providers and NASA Safety and Mission Assurance personnel. Ideally, this prototype will increase interest in the concept of standard hazard automation and lead to the full-scale production of a user-ready application.

  15. Science education standards

    Energy Technology Data Exchange (ETDEWEB)

    Alberts, B.

    1994-12-31

    This paper describes the National Science Education Standards that are being developed at the National Research Council. The Standards are being developed for the following areas: content, teaching, assessment, program, and system. The national science standards will call for the kind of science that provides both an understanding of the basic concepts needed for success in our high technology society, and the acquisition of process skills, or the ability to proceed step by step to solve a practical problem. Science should become a core subject like reading, writing and math in grades K-12. At all levels, the material taught should be interesting, both to students and to teachers. The profession of science teaching must become an attractive one, which is possible to do well without superhuman effort. The scientific community must accept responsibility for achieving these goals.

  16. Fasteners 5 basic standards

    CERN Document Server

    2011-01-01

    This 3rd edition of DIN Handbook 193 contains 38 fundamental standards on fasteners, covering such areas as countersinks and counterbores, widths across flats, thread run-outs and thread undercuts, bolt and screw ends, stud ends and tapped holes for compression couplings, driving features, tolerances for screw threads and nomenclature. New to this compilation are DIN 34824 dealing with 12 point sockets for bolts and screws and DIN EN ISO 15065 which reflects current practice in Europe with regard to countersinks for countersunk head screws. Also included for the first time is DIN EN ISO 225 "Fasteners - Bolts, screws, studs and nuts - Symbols and descriptions of dimensions" which, together with DIN ISO 1891, now also incorporates terminology in Chinese, Japanese and Swedish. Four standards have been revised for this edition, among them DIN 918 Supplement 3 which provides information on the current status of European standardization relating to fasteners. DIN Handbook 193 is one of a series of six handbooks on...

  17. Islam, Standards, and Technoscience

    DEFF Research Database (Denmark)

    Fischer, Johan

    Halal (literally, "permissible" or "lawful") production, trade, and standards have become essential to state-regulated Islam and to companies in contemporary Malaysia and Singapore, giving these two countries a special position in the rapidly expanding global market for halal products......, this book provides an exploration of the role of halal production, trade, and standards. Fischer explains how the global markets for halal comprise divergent zones in which Islam, markets, regulatory institutions, and technoscience interact and diverge. Focusing on the "bigger institutional picture......" that frames everyday halal consumption, Fischer provides a multisited ethnography of the overlapping technologies and techniques of production, trade, and standards that together warrant a product as "halal," and thereby help to format the market. Exploring global halal in networks, training, laboratories...

  18. Standards and quality

    CERN Document Server

    El-Tawil, Anwar

    2015-01-01

    The book brings together a number of subjects of prime importance for any practicing engineer and, students of engineering. The book explains the concepts and functions of voluntary standards, mandatory technical regulations, conformity assessment (testing and measurement of products), certification, quality and quality management systems as well as other management systems such as environmental, social responsibility and food safety management systems.The book also gives a comprehensive description of the role of metrology systems that underpin conformity assessment. A description is given of typical national systems of standards, quality and metrology and how they relate directly or through regional structures to international systems. The book also covers the relation between standards and trade and explains the context and stipulations of the Technical Barriers to Trade Agreement of the World Trade Organization (WTO).

  19. Ethics, standards, and TQM.

    Science.gov (United States)

    Botticelli, M G

    1995-04-01

    The most important ethical issue for our profession is the responsibility to assure the care delivered by our colleagues and ourselves meets a self-imposed standard of excellence. There is anecdotal and experimental evidence that we have not fulfilled this obligation. Peer review has proven, for a number of reasons, to be ineffective; however, improvements in the epidemiologic sciences should provide better standards and total quality management (TQM) might prove to be of value in monitoring, comparing and improving the decisions made by physicians. Its promise lies in its emphasis on statistical analysis, its focus on systematic rather than human error, and its use of outcomes as standards. These methods, however, should not diminish our other professional responsibilities: Altruism, peer review, and in Hippocrates' words "to prescribe regimens for the good of our patients-and never do harm to anyone."

  20. Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Pier Alberto Testoni

    2007-01-01

    Full Text Available Optical coherence tomography (OCT is an optical imaging modality that performs high-resolution, cross-sectional, subsurface tomographic imaging of the microstructure of tissues. The physical principle of OCT is similar to that of B-mode ultrasound imaging, except that it uses infrared light waves rather than acoustic waves. The in vivo resolution is 10–25 times better (about 10 µm than with high-frequency ultrasound imaging, but the depth of penetration is limited to 1–3 mm, depending on tissue structure, depth of focus of the probe used, and pressure applied to the tissue surface. In the last decade, OCT technology has evolved from an experimental laboratory tool to a new diagnostic imaging modality with a wide spectrum of clinical applications in medical practice, including the gastrointestinal tract and pancreatico-biliary ductal system. OCT imaging from the gastrointestinal tract can be done in humans by using narrow-diameter, catheter-based probes that can be inserted through the accessory channel of either a conventional front-view endoscope, for investigating the epithelial structure of the gastrointestinal tract, or a side-view endoscope, inside a standard transparent ERCP (endoscopic retrograde cholangiopancreatography catheter, for investigating the pancreatico-biliary ductal system. The esophagus and esophagogastric junction have been the most widely investigated organs so far; more recently, duodenum, colon, and the pancreatico-biliary ductal system have also been extensively investigated. OCT imaging of the gastrointestinal wall structure is characterized by a multiple-layer architecture that permits an accurate evaluation of the mucosa, lamina propria, muscularis mucosae, and part of the submucosa. The technique may therefore be used to identify preneoplastic conditions of the gastrointestinal tract, such as Barrett's epithelium and dysplasia, and evaluate the depth of penetration of early-stage neoplastic lesions. OCT imaging

  1. Optical Frequency Upconversion Technique for Transmission of Wireless MIMO-Type Signals over Optical Fiber

    Directory of Open Access Journals (Sweden)

    R. Q. Shaddad

    2014-01-01

    Full Text Available The optical fiber is well adapted to pass multiple wireless signals having different carrier frequencies by using radio-over-fiber (ROF technique. However, multiple wireless signals which have the same carrier frequency cannot propagate over a single optical fiber, such as wireless multi-input multi-output (MIMO signals feeding multiple antennas in the fiber wireless (FiWi system. A novel optical frequency upconversion (OFU technique is proposed to solve this problem. In this paper, the novel OFU approach is used to transmit three wireless MIMO signals over a 20 km standard single mode fiber (SMF. The OFU technique exploits one optical source to produce multiple wavelengths by delivering it to a LiNbO3 external optical modulator. The wireless MIMO signals are then modulated by LiNbO3 optical intensity modulators separately using the generated optical carriers from the OFU process. These modulators use the optical single-sideband with carrier (OSSB+C modulation scheme to optimize the system performance against the fiber dispersion effect. Each wireless MIMO signal is with a 2.4 GHz or 5 GHz carrier frequency, 1 Gb/s data rate, and 16-quadrature amplitude modulation (QAM. The crosstalk between the wireless MIMO signals is highly suppressed, since each wireless MIMO signal is carried on a specific optical wavelength.

  2. Optical frequency upconversion technique for transmission of wireless MIMO-type signals over optical fiber.

    Science.gov (United States)

    Shaddad, R Q; Mohammad, A B; Al-Gailani, S A; Al-Hetar, A M

    2014-01-01

    The optical fiber is well adapted to pass multiple wireless signals having different carrier frequencies by using radio-over-fiber (ROF) technique. However, multiple wireless signals which have the same carrier frequency cannot propagate over a single optical fiber, such as wireless multi-input multi-output (MIMO) signals feeding multiple antennas in the fiber wireless (FiWi) system. A novel optical frequency upconversion (OFU) technique is proposed to solve this problem. In this paper, the novel OFU approach is used to transmit three wireless MIMO signals over a 20 km standard single mode fiber (SMF). The OFU technique exploits one optical source to produce multiple wavelengths by delivering it to a LiNbO3 external optical modulator. The wireless MIMO signals are then modulated by LiNbO3 optical intensity modulators separately using the generated optical carriers from the OFU process. These modulators use the optical single-sideband with carrier (OSSB+C) modulation scheme to optimize the system performance against the fiber dispersion effect. Each wireless MIMO signal is with a 2.4 GHz or 5 GHz carrier frequency, 1 Gb/s data rate, and 16-quadrature amplitude modulation (QAM). The crosstalk between the wireless MIMO signals is highly suppressed, since each wireless MIMO signal is carried on a specific optical wavelength.

  3. Culture of standardization

    OpenAIRE

    García Pantigozo, Manuel; Yenque de Dios, Julio; Docente FII-UNMSM; Gil Benites, Wilber

    2014-01-01

    The culture of standardization has become a competitive advantage; develop those who will survive, and those who do not, will be isolated in the market. Have been established quality standards (ISO 9000), environmental (ISO 14000), on laboratory accreditation (ISO 25) on food (HACCP) and drugs (NCF).  La cultura de la normalización se ha convertido en una ventaja competitiva; quienes la desarrollen sobrevivirán, y los que no, quedarán aislados del mercado. Se han establecido normas sobr...

  4. Airborne Network Camera Standard

    Science.gov (United States)

    2015-06-01

    primarily to cover terminology included in or consistent with the GigE Vision (GEV) and IRIG 106-13 Chapter 10 standards for command and control over a...cover terminology included in or consistent with the GigE Vision1 (GEV) and IRIG 106-13 Chapter 102 standards for command and control over a variety of... IRIG 106-13. June 2013. May be superseded by update. Available at http://www.wsmr.army.mil/RCCsite/Documents/106%20Previous%20Versions/106

  5. Standardization Historical Overview

    Institute of Scientific and Technical Information of China (English)

    Wang Ping

    2008-01-01

    @@ 1. Indroduction Standardization germinated in ancient times, and began to develop from the beginning of the in-dustrial revolution, and took off in the later years of the 19th Century. It has been closely connected with the development of science and technology, as well as industry and trade throughout human histo-ry. Standardization now plays an important role in nearly every aspect of human life, in different sec-tors of industry and society. It has had a great im-pact on our lives.

  6. Reactive standard deontic logic

    OpenAIRE

    Gabbay, Dov M.; Straßer, Christian

    2015-01-01

    We introduce a reactive variant of SDL (standard deontic logic): SDLR1 (reactive standard deontic logic). Given a Kripkean view on the semantics of SDL in terms of directed graphs where arrows -> represent the accessibility relation between worlds, reactive models add two elements: arrows -> are labelled as 'active' or 'inactive', and double arrows a dagger connect arrows, e.g. (x(1) -> x(2)) a dagger (x(3) -> x(4)). The idea is that passing through x(1) -> x(2) activates a switch represented...

  7. Coordinate Standard Measurement Development

    Energy Technology Data Exchange (ETDEWEB)

    Hanshaw, R.A.

    2000-02-18

    A Shelton Precision Interferometer Base, which is used for calibration of coordinate standards, was improved through hardware replacement, software geometry error correction, and reduction of vibration effects. Substantial increases in resolution and reliability, as well as reduction in sampling time, were achieved through hardware replacement; vibration effects were reduced substantially through modification of the machine component dampening and software routines; and the majority of the machine's geometry error was corrected through software geometry error correction. Because of these modifications, the uncertainty of coordinate standards calibrated on this device has been reduced dramatically.

  8. Conference: STANDARD MODEL @ LHC

    CERN Multimedia

    2012-01-01

    HCØ institute Universitetsparken 5 DK-2100 Copenhagen Ø Denmark Room: Auditorium 2 STANDARD MODEL @ LHC Niels Bohr International Academy and Discovery Center 10-13 April 2012 This four day meeting will bring together both experimental and theoretical aspects of Standard Model phenomenology at the LHC. The very latest results from the LHC experiments will be under discussion. Topics covered will be split into the following categories:     * QCD (Hard,Soft & PDFs)     * Vector Boson production     * Higgs searches     * Top Quark Physics     * Flavour physics

  9. Passive endoscopic polarization sensitive optical coherence tomography with completely fiber based optical components

    Science.gov (United States)

    Cahill, Lucas; Lee, Anthony M. D.; Pahlevaninezhad, Hamid; Ng, Samson; MacAulay, Calum E.; Poh, Catherine; Lane, Pierre

    2015-03-01

    Polarization Sensitive Optical Coherence Tomography (PSOCT) is a functional extension of Optical Coherence Tomography (OCT) that is sensitive to well-structured, birefringent tissue such as scars, smooth muscle and cartilage. In this work, we present a novel completely fiber based swept source PSOCT system using a fiber-optic rotary pullback catheter. This PSOCT implementation uses only passive optical components and requires no calibration while adding minimal additional cost to a standard structural OCT imaging system. Due to its complete fiber construction, the system can be made compact and robust, while the fiber-optic catheter allows access to most endoscopic imaging sites. The 1.5mm diameter endoscopic probe can capture 100 frames per second at pullback speeds up to 15 mm/s allowing rapid traversal of large imaging fields. We validate the PSOCT system with known birefringent tissues and demonstrate in vivo PSOCT imaging of human oral scar tissue.

  10. Software Defined Optical Networks and Its Innovation Environment

    Institute of Scientific and Technical Information of China (English)

    LI Yajie; ZHAO Yongli; ZHANG Jie; WANG Dajiang; WANG Jiayu

    2016-01-01

    Software defined optical networks (SDONs) integrate software defined technology with optical communication networks and represent the promising development trend of future optical networks. The key technologies for SDONs include software⁃defined optical transmission, switching, and networking. The main features include control and transport separation, hard⁃ware universalization, protocol standardization, controllable optical network, and flexible optical network applications. This paper introduces software defined optical networks and its innovation environment, in terms of network architecture, protocol extension solution, experiment platform and typical applications. Batch testing has been conducted to evaluate the performance of this SDON testbed. The results show that the SDON testbed has good scalability in different sizes. Meanwhile, we notice that controller output bandwidth has great influence on lightpath setup delay.

  11. Nonlinear fiber optics

    CERN Document Server

    Agrawal, Govind P

    2001-01-01

    The Optical Society of America (OSA) and SPIE - The International Society for Optical Engineering have awarded Govind Agrawal with an honorable mention for the Joseph W. Goodman Book Writing Award for his work on Nonlinear Fiber Optics, 3rd edition.Nonlinear Fiber Optics, 3rd Edition, provides a comprehensive and up-to-date account of the nonlinear phenomena occurring inside optical fibers. It retains most of the material that appeared in the first edition, with the exception of Chapter 6, which is now devoted to the polarization effects relevant for light propagation in optical

  12. Introduction to nonimaging optics

    CERN Document Server

    Chaves, Julio

    2015-01-01

    Introduction to Nonimaging Optics covers the theoretical foundations and design methods of nonimaging optics, as well as key concepts from related fields. This fully updated, revised, and expanded Second Edition: Features a new and intuitive introduction with a basic description of the advantages of nonimaging opticsAdds new chapters on wavefronts for a prescribed output (irradiance or intensity), infinitesimal étendue optics (generalization of the aplanatic optics), and Köhler optics and color mixingIncorporates new material on the simultaneous multiple surface (SMS) design method in 3-D, int

  13. Organic nonlinear optical materials

    Science.gov (United States)

    Umegaki, S.

    1987-01-01

    Recently, it became clear that organic compounds with delocalized pi electrons show a great nonlinear optical response. Especially, secondary nonlinear optical constants of more than 2 digits were often seen in the molecular level compared to the existing inorganic crystals such as LiNbO3. The crystallization was continuously tried. Organic nonlinear optical crystals have a new future as materials for use in the applied physics such as photomodulation, optical frequency transformation, opto-bistabilization, and phase conjugation optics. Organic nonlinear optical materials, e.g., urea, O2NC6H4NH2, I, II, are reviewed with 50 references.

  14. Latching micro optical switch

    Science.gov (United States)

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21

    An optical switch reliably maintains its on or off state even when subjected to environments where the switch is bumped or otherwise moved. In addition, the optical switch maintains its on or off state indefinitely without requiring external power. External power is used only to transition the switch from one state to the other. The optical switch is configured with a fixed optical fiber and a movable optical fiber. The movable optical fiber is guided by various actuators in conjunction with a latching mechanism that configure the switch in one position that corresponds to the on state and in another position that corresponds to the off state.

  15. Handbook of fiber optic data communication a practical guide to optical networking

    CERN Document Server

    DeCusatis, Casimer

    2008-01-01

    The third edition of this Handbook provides a comprehensive, easy to use guide to the field of optical fiber data communications. Written by experts in the industry from major companies such as IBM, Cisco and Nortel, the Handbook is a key reference for optical fiber technology, networking, protocols, applications, manufacturing, and future directions. It includes chapters on all the major industry standards, written by the same experts who developed them.This edition contains new material on transceiver form factors (QSFP, SFP +, XFP, X2), manufacturing standards, including JEDEC and R

  16. Comparison of optic area measurement using fundus photography and optical coherence tomography between optic nerve head drusen and control subjects.

    Science.gov (United States)

    Flores-Rodríguez, Patricia; Gili, Pablo; Martín-Ríos, María Dolores; Grifol-Clar, Eulalia

    2013-03-01

    To compare optic disc area measurement between optic nerve head drusen (ONHD) and control subjects using fundus photography, time-domain optical coherence tomography (TD-OCT) and spectral-domain optical coherence tomography (SD-OCT). We also made a comparison between each of the three techniques. We performed our study on 66 eyes (66 patients) with ONHD and 70 healthy control subjects (70 controls) with colour ocular fundus photography at 20º (Zeiss FF 450 IR plus), TD-OCT (Stratus OCT) with the Fast Optic Disc protocol and SD-OCT (Cirrus OCT) with the Optic Disc Cube 200 × 200 protocol for measurement of the optic disc area. The measurements were made by two observers and in each measurement a correction of the image magnification factor was performed. Measurement comparison using the Student's t-test/Mann-Whitney U test, the intraclass correlation coefficient, Pearson/Spearman rank correlation coefficient and the Bland-Altman plot was performed in the statistical analysis. Mean and standard deviation (SD) of the optic disc area in ONHD and in controls was 2.38 (0.54) mm(2) and 2.54 (0.42) mm(2), respectively with fundus photography; 2.01 (0.56) mm(2) and 1.66 (0.37) mm(2), respectively with TD-OCT, and 2.03 (0.49) mm(2) and 1.75 (0.38) mm(2), respectively with SD-OCT. In ONHD and controls, repeatability of optic disc area measurement was excellent with fundus photography and optical coherence tomography (TD-OCT and SD-OCT), but with a low degree of agreement between both techniques. Optic disc area measurement is smaller in ONHD compared to healthy subjects with fundus photography, unlike time-domain and spectral-domain optical coherence tomography in which the reverse is true. Both techniques offer good repeatability, but a low degree of correlation and agreement, which means that optic disc area measurement is not interchangeable or comparable between techniques. Ophthalmic & Physiological Optics © 2013 The College of Optometrists.

  17. Beyond the Standard Model

    CERN Document Server

    Csáki, C

    2015-01-01

    We introduce aspects of physics beyond the Standard Model focusing on supersymmetry, extra dimensions, and a composite Higgs as solutions to the Hierarchy problem. Lectures given at the 2013 European School of High Energy Physics, Parádfürdo, Hungary, 5-18 June 2013.

  18. Telecommunications administration standard

    Energy Technology Data Exchange (ETDEWEB)

    Gustwiller, K.D. [GTE Customer Networks, Albuquerque, NM (United States)

    1996-05-01

    The administration of telecommunications is critical to proper maintenance and operation. The intent is to be able to properly support telecommunications for the distribution of all information within a building/campus. This standard will provide a uniform administration scheme that is independent of applications, and will establish guidelines for owners, installers, designers and contractors. This standard will accommodate existing building wiring, new building wiring and outside plant wiring. Existing buildings may not readily adapt to all applications of this standard, but the requirement for telecommunications administration is applicable to all buildings. Administration of the telecommunications infrastructure includes documentation (labels, records, drawings, reports, and work orders) of cables, termination hardware, patching and cross-connect facilities, telecommunications rooms, and other telecommunications spaces (conduits, grounding, and cable pathways are documented by Facilities Engineering). The investment in properly documenting telecommunications is a worthwhile effort. It is necessary to adhere to these standards to ensure quality and efficiency for the operation and maintenance of the telecommunications infrastructure for Sandia National Laboratories.

  19. A Standard of Support.

    Science.gov (United States)

    Wheat, Dave; Cramer, James E.; Cramer, Mary Kay

    2000-01-01

    Principals can support teachers' pursuit of National Board of Professional Teaching Standards certification by learning about the NBPTS's certification process, putting candidates in contact with NBPTS support programs, facilitating access to technology, providing building access on weekends, volunteering to photocopy or obtain needed materials,…

  20. Setting Environmental Standards

    Science.gov (United States)

    Fishbein, Gershon

    1975-01-01

    Recent court decisions have pointed out the complexities involved in setting environmental standards. Environmental health is composed of multiple causative agents, most of which work over long periods of time. This makes the cause-and-effect relationship between health statistics and environmental contaminant exposures difficult to prove in…

  1. Organizational Hiring Standards.

    Science.gov (United States)

    Cohen, Yinon; Pfeffer, Jeffrey

    1986-01-01

    Using a sample of 254 San Francisco Bay Area establishments, this study examines determinants of organizational hiring selectivity, including use of educational credentials, tests, and screening devices for both white and blue collar workers. Apparently, hiring standards reflect organizations' skill requirements and group preferences for these…

  2. Accessibility Standards, Illustrated.

    Science.gov (United States)

    Jones, Michael A.

    The book sets forth Illinois environmental accessibility standards for disabled persons based on observation and interview data. Photographs, drawings, and detailed floor plans are included in sections dealing with human data (including space requirements for maneuvering wheelchairs, color blindness, incontinence, and severe auditory or visual…

  3. Standardized Curriculum for Cosmetology.

    Science.gov (United States)

    Mississippi State Dept. of Education, Jackson. Office of Vocational, Technical and Adult Education.

    Standardized curricula are provided for two courses for the secondary vocational education program in Mississippi: cosmetology I and II. The 18 units in cosmetology I are as follows: introduction to cosmetology; Vocational Industrial Clubs of America; the look you like; bacteriology; sterilization and sanitation; hair and disorders; draping,…

  4. Standard PWR for Italy

    Energy Technology Data Exchange (ETDEWEB)

    Negroni, A.; Velona, F. (Ente Nazionale per l' Energia Elettrica, Rome (Italy))

    1983-03-01

    A description is given of the general design for the standard PWR which will be used in the seven to eight nuclear power stations provided for in the Italian national energy plan. Special features to meet Italian conditions include double containment and a common foundation mat for the reactor, auxiliary and fuel buildings.

  5. Standards and Criteria

    Science.gov (United States)

    Glass, Gene V.

    2011-01-01

    This monograph has grown out of a series of discussions and a six-month period of reading and reflecting on the literature which were initiated by Fritz Mosher's suggestions to the National Assessment of Educational Progress (NAEP) to examine the "standards" question. Conversations with Mosher himself and the staff of NAEP have been most…

  6. On Standard Ideals

    Institute of Scientific and Technical Information of China (English)

    Zhi De YU

    2003-01-01

    In the paper, we study a class of standard ideals which are more general than the m-primarystandard ideals discussed in [2]. We will prove an important equality concerning I-weak sequences; thusa generalization of the equality of [2] is established.

  7. Accessibility Standards, Illustrated.

    Science.gov (United States)

    Jones, Michael A.

    The book sets forth Illinois environmental accessibility standards for disabled persons based on observation and interview data. Photographs, drawings, and detailed floor plans are included in sections dealing with human data (including space requirements for maneuvering wheelchairs, color blindness, incontinence, and severe auditory or visual…

  8. Setting the Standard

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The country’s self-developed document format standard faces a difficult decision and possible extinction as it goes up against mighty Microsoft Since Microsoft’s Office Open Extensible Markup Language (OOXML)document format was accepted as an international stan- dard by the International Organization for

  9. Elevating standards, improving safety.

    Science.gov (United States)

    Clarke, Richard

    2014-08-01

    In our latest 'technical guidance' article, Richard Clarke, sales and marketing director at one of the UK's leading lift and escalator specialists, Schindler, examines some of the key issues surrounding the specification, maintenance, and operation of lifts in hospitals to help ensure the highest standards of safety and reliability.

  10. International Financial Reporting Standards

    DEFF Research Database (Denmark)

    Pontoppidan, Caroline Aggestam

    2011-01-01

    The advance of International Financial Reporting Standards (IFRS) across the globe has accelerated over the last few years. This is placing increasing demands on educators to respond to these changes by an increased focus on IFRS in the curricula of accounting students. This paper reviews a range...... of educational texts covering IFRS within the context of a review of the progress of IFRS themselves....

  11. Standardization of Sign Languages

    Science.gov (United States)

    Adam, Robert

    2015-01-01

    Over the years attempts have been made to standardize sign languages. This form of language planning has been tackled by a variety of agents, most notably teachers of Deaf students, social workers, government agencies, and occasionally groups of Deaf people themselves. Their efforts have most often involved the development of sign language books…

  12. 4G Standards

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ China plans to submit homegrown fourth-generation (4G) mobile technology standards to the International Telecommunications Union (ITU) between 2008 and 2009, according to Wen Ku, director of the Department of Science and Technology at the Ministry of Information Industry.

  13. International Financial Reporting Standards

    DEFF Research Database (Denmark)

    Pontoppidan, Caroline Aggestam

    2011-01-01

    The advance of International Financial Reporting Standards (IFRS) across the globe has accelerated over the last few years. This is placing increasing demands on educators to respond to these changes by an increased focus on IFRS in the curricula of accounting students. This paper reviews a range...

  14. Herbal reference standards.

    Science.gov (United States)

    Schwarz, Michael; Klier, Bernhard; Sievers, Hartwig

    2009-06-01

    This review describes the current definitions and regulatory requirements that apply to reference standards that are used to analyse herbal products. It also describes and discusses the current use of reference substances and reference extracts in the European and United States pharmacopoeias.

  15. Standards and Interoperability

    Institute of Scientific and Technical Information of China (English)

    Stephen McGibbon

    2006-01-01

    @@ I am sure that there will be much discussion at the upcoming Baltic IT&T 2005 conference about standards and interoperability, and so I thought I would try to contribute to the debate with this, the first of four articles that I will write for this journal over the coming months.

  16. Detection of non-standard atmospheric effects in FSO systems

    Science.gov (United States)

    Wilfert, Otakar; Poliak, Juraj; Barcík, Peter; Arce-Diego, José L.; Fanjul-Vélez, Félix; Salas-García, Irene; Ortega Quijano, Noé

    2013-09-01

    Modern free-space optical (FSO) communication systems in many aspects overcome wire or radio communications. They offer a license-free operation and a large bandwidth. Operation of outdoor FSO links struggles with many atmospheric phenomena that deteriorate phase and amplitude of the transmitted optical beam. Thanks to the recent advancing development, these effects are more or less well understood and described. Goal driven research increased the link availability. Besides increasing the availability of data links it is necessary to focus on the accuracy and reliability of testing optical links. Research of the data optical links is focused on the transmission of a large amount of data whereas the testing FSO link is designed to achieve maximal resolution and sensitivity thus improving accuracy and repeatability of the atmospheric effects measurement. Given the fact that testing links are located in the measured media, they are themselves influenced by it. Phenomena such as the condensation on transceiver windows (rain, frost) and the deviation of the optical beam path caused by the wind are referred to as non-standard effects. Non-standard effects never occur independently; therefore we must always verify the cross-sensitivity of the testing link. In the paper we respond to an increasing number of articles dealing with influence of the atmosphere on the link but ignoring the cross-sensitivity of the testing link on other variables than tested. In conclusion, we carry out qualitative and quantitative analysis of self-identified non-standard effects.

  17. Campus fiber optic enterprise networks

    Science.gov (United States)

    Weeks, Richard A.

    1991-02-01

    The proliferation of departmental LANs in campus environments has driven network technology to the point where construction of token ring fiber-optic backbone systems is now a cost-effective alternative. This article will discuss several successful real life case history applications of token ring fiber in a campus setting each with unique distance and load factor requirements. It is hoped that these examples will aid in the understanding planning and implementation of similar installations. It will also attempt to provide important information on the emerging Fiber Distributed Data Interface (FDDI) standard.

  18. DOE standard: Radiological control

    Energy Technology Data Exchange (ETDEWEB)

    1999-07-01

    The Department of Energy (DOE) has developed this Standard to assist line managers in meeting their responsibilities for implementing occupational radiological control programs. DOE has established regulatory requirements for occupational radiation protection in Title 10 of the Code of Federal Regulations, Part 835 (10 CFR 835), ``Occupational Radiation Protection``. Failure to comply with these requirements may lead to appropriate enforcement actions as authorized under the Price Anderson Act Amendments (PAAA). While this Standard does not establish requirements, it does restate, paraphrase, or cite many (but not all) of the requirements of 10 CFR 835 and related documents (e.g., occupational safety and health, hazardous materials transportation, and environmental protection standards). Because of the wide range of activities undertaken by DOE and the varying requirements affecting these activities, DOE does not believe that it would be practical or useful to identify and reproduce the entire range of health and safety requirements in this Standard and therefore has not done so. In all cases, DOE cautions the user to review any underlying regulatory and contractual requirements and the primary guidance documents in their original context to ensure that the site program is adequate to ensure continuing compliance with the applicable requirements. To assist its operating entities in achieving and maintaining compliance with the requirements of 10 CFR 835, DOE has established its primary regulatory guidance in the DOE G 441.1 series of Guides. This Standard supplements the DOE G 441.1 series of Guides and serves as a secondary source of guidance for achieving compliance with 10 CFR 835.

  19. Active optical zoom system

    Science.gov (United States)

    Wick, David V.

    2005-12-20

    An active optical zoom system changes the magnification (or effective focal length) of an optical imaging system by utilizing two or more active optics in a conventional optical system. The system can create relatively large changes in system magnification with very small changes in the focal lengths of individual active elements by leveraging the optical power of the conventional optical elements (e.g., passive lenses and mirrors) surrounding the active optics. The active optics serve primarily as variable focal-length lenses or mirrors, although adding other aberrations enables increased utility. The active optics can either be LC SLMs, used in a transmissive optical zoom system, or DMs, used in a reflective optical zoom system. By appropriately designing the optical system, the variable focal-length lenses or mirrors can provide the flexibility necessary to change the overall system focal length (i.e., effective focal length), and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses. The active optics can provide additional flexibility by allowing magnification to occur anywhere within the FOV of the system, not just on-axis as in a conventional system.

  20. Department of Energy Standards Index

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This TSL, intended for use in selecting and using DOE technical standards and other Government and non-Government standards, provides listing of current and inactive DOE technical standards, non-Government standards adopted by DOE, other Government documents in which DOE has a recorded interest, and cancelled DOE technical standards.

  1. Achromatic optical diode in fiber optics

    CERN Document Server

    Berent, Michal; Vitanov, Nikolay V

    2013-01-01

    We propose a broadband optical diode, which is composed of one achromatic reciprocal quarter-wave plate and one non-reciprocal quarter-wave plate, both placed between two crossed polarizers. The presented design of achromatic wave plates relies on an adiabatic evolution of the Stokes vector, thus, the scheme is robust and efficient. The possible simple implementation using fiber optics is suggested.

  2. All-Optical Switches in Optical Time-Division Multiplexing Technology: Theory,Experience and Application

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Optical time division multiplexing (OTDM) is one of thepromisinig ways for the future high-speed optical fiber communication networks. All-optical switch is, being one of the core technologies of OTDM systems and networks, crucial to realize the various signal processes including time-division demultiplexing, packet switching, all-optical regenerating and so on. This thesis mainly studies various all-optical switch technologies and their utilization in the fields of all-optical signal processings in the OTDM systems and networks. The main jobs are listed as follows.(1) A novel all-optical ultrafast demultiplexing scheme using the soliton self-trapping effect in birefringent fiber is proposed.(2) The demultiplexing performance of the Nonlinear Optical Loop Mirror(NOLM) is thoroughly analyzed and its optimization is further discussed.(3) The performance analysis and the configuration optimization of the all-optical switches based on the Semiconductor Optical Amplifier(SOA) are systematically presented. The speed limitation of the all-optical SOA switches induced by the fast gain depletion of SOA is discussed. Besides, a novel SOA switch is proposed, which adopts the asymmetric Mach-Zehnder Interferometer configuration.(4) The 8×2\\^5 Gb/s OTDM experimental transmission system along 105 km standard fiber is realized using the NOLM demultiplexer.(5) The NOLM switch is used to realize the all-optical 3R regeneration of 2\\^5 Gb/s Return-to-Zero signal.(6) The feasibility and limitation of the all-optical SOA packet switch is discussed. And a developed MZI configuration of SOA packet switch is further shown to improve the packet switching performance. Finally, an all-optical packet dropping node suitable in the networks with ring or bus configuration and an all-optical packet switching node in the ShuffleNet networks are proposed to show the feasibility of all-optical packet switching through combining the all-optical switches and the reasonable logic decisions.

  3. DOE technical standards list: Department of Energy standards index

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    This technical standards list (TSL) was prepared for use by personnel involved in the selection and use of US DOE technical standards and other government and non-government standards. This TSL provides listings of current DOE technical standards, non-government standards that have been adopted by DOE, other government documents in which DOE has a recorded interest, and cancelled DOE technical standards. Standards are indexed by type in the appendices to this document. Definitions of and general guidance for the use of standards are also provided.

  4. Acousto-optic laser optical feedback imaging

    CERN Document Server

    Jacquin, Olivier; Lacot, Eric; Hugon, Olivier; De Chatellus, Hugues Guillet; François, Ramaz

    2012-01-01

    We present a photon noise and diffraction limited imaging method combining the imaging laser and ultrasonic waves. The laser optical feedback imaging (LOFI) technique is an ultrasensitive imaging method for imaging objects through or embedded within a scattering medium. However, LOFI performances are dramatically limited by parasitic optical feedback occurring in the experimental setup. In this work, we have tagged the ballistic photons by an acousto-optic effect in order to filter the parasitic feedback effect and to reach the theoretical and ultimate sensitivity of the LOFI technique. We present the principle and the experimental setup of the acousto-optic laser optical feedback imaging (AO-LOFI) technique, and we demonstrate the suppression of the parasitic feedback.

  5. Optical Quantum Computing

    National Research Council Canada - National Science Library

    Jeremy L. O'Brien

    2007-01-01

    In 2001, all-optical quantum computing became feasible with the discovery that scalable quantum computing is possible using only single-photon sources, linear optical elements, and single-photon detectors...

  6. Fiber Optics Technology.

    Science.gov (United States)

    Burns, William E.

    1986-01-01

    Discusses various applications of fiber optics technology: information systems, industrial robots, medicine, television, transportation, and training. Types of jobs that will be available with fiber optics training (such as electricians and telephone cable installers and splicers) are examined. (CT)

  7. Fiber Optics Instrumentation Development

    Science.gov (United States)

    Chan, Patrick Hon Man; Parker, Allen R., Jr.; Richards, W. Lance

    2010-01-01

    This is a general presentation of fiber optics instrumentation development work being conducted at NASA Dryden for the past 10 years and recent achievements in the field of fiber optics strain sensors.

  8. Optical solenoid beams

    National Research Council Canada - National Science Library

    Lee, Sang-Hyuk; Roichman, Yohai; Grier, David G

    2010-01-01

    We introduce optical solenoid beams, diffractionless solutions of the Helmholtz equation whose diffraction-limited in-plane intensity peak spirals around the optical axis, and whose wavefronts carry...

  9. Ultra-high-speed optical signal processing of Tbaud data signals

    DEFF Research Database (Denmark)

    Oxenløwe, Leif Katsuo; Galili, Michael; Mulvad, Hans Christian Hansen;

    2010-01-01

    We describe methods to generate and optically signal process Tbaud serial optical data signals. We present sub-systems making serial optical Tbit/s systems compatible with standard Ethernet data for data centre applications, and present Tbit/s results using a.o. silicon nanowires....

  10. Optical zilch and Noether's theorem

    CERN Document Server

    Philbin, T G

    2013-01-01

    A simple conserved quantity for electromagnetic fields in vacuum was discovered by Lipkin in 1964. In recent years this "zilch" has been used as a measure of the chirality of light. The conservation of optical zilch is here shown to be due to a simple symmetry of the standard electromagnetic action. Other investigations of the symmetry underlying zilch conservation have not been based on transformations of the dynamical variables of the standard action (the vector and scalar potentials). The symmetry transformation allows the identification of zilch eigenstates, which are shown to be circularly polarized plane waves. The same symmetry is present for electromagnetism in a homogeneous, dispersive medium, allowing the derivation of the zilch density and flux in such a medium.

  11. Optical antennas and plasmonics

    OpenAIRE

    Park, Q-Han

    2009-01-01

    Optical antenna is a nanoscale miniaturization of radio or microwave antennas that is also governed by the rule of plasmonics. We introduce various types of optical antenna and make an overview of recent developments in optical antenna research. The role of local and surface plasmons in optical antenna is explained through antenna resonance and resonance conditions for specific metal structures are explicitly obtained. Strong electric field is shown to exist within a highly localized region o...

  12. Fibre-Optic Gyroscope

    Directory of Open Access Journals (Sweden)

    V. N. Saxena

    1983-04-01

    Full Text Available Comparative study of mechanical, ring-laser and fibre-optic gyroscopes has been made. The single mode fibre-optic gyroscope having a large number of turns of the optical fibre in the spool, replacing He-Ne gas laser by a GaAs laser diode, there by reducing the noise level, and using fully integrated fibre-optics, works out to be the best in the final analysis, for safe navigation and homing of the guided missiles.

  13. Giant optical manipulation.

    Science.gov (United States)

    Shvedov, Vladlen G; Rode, Andrei V; Izdebskaya, Yana V; Desyatnikov, Anton S; Krolikowski, Wieslaw; Kivshar, Yuri S

    2010-09-10

    We demonstrate a new principle of optical trapping and manipulation increasing more than 1000 times the manipulation distance by harnessing strong thermal forces while suppressing their stochastic nature with optical vortex beams. Our approach expands optical manipulation of particles into a gas media and provides a full control over trapped particles, including the optical transport and pinpoint positioning of ∼100  μm objects over a meter-scale distance with ±10  μm accuracy.

  14. Photonic crystal optical memory

    Science.gov (United States)

    Lima, A. Wirth; Sombra, A. S. B.

    2011-06-01

    After several decades pushing the technology and the development of the world, the electronics is giving space for technologies that use light. We propose and analyze an optical memory embedded in a nonlinear photonic crystal (PhC), whose system of writing and reading data is controlled by an external command signal. This optical memory is based on optical directional couplers connected to a shared optical ring. Such a device can work over the C-Band of ITU (International Telecommunication Union).

  15. Progress in optics

    CERN Document Server

    Wolf, Emil

    2009-01-01

    In the fourty-seven years that have gone by since the first volume of Progress in Optics was published, optics has become one of the most dynamic fields of science. The volumes in this series which have appeared up to now contain more than 300 review articles by distinguished research workers, which have become permanent records for many important developments.- Backscattering and Anderson localization of light- Advances in oliton manipulation in optical lattices- Fundamental quantum noise in optical amplification- Invisibility cloaks

  16. Emerging Correlation Optics

    DEFF Research Database (Denmark)

    Angelsky, Oleg V.; Gbur, Gregory J.; Polyanskii, Peter;

    2012-01-01

    This feature issue of Applied Optics contains a series of selected papers reflecting the state-of-the-art of correlation optics and showing synergetics between the theoretical background and experimental techniques.......This feature issue of Applied Optics contains a series of selected papers reflecting the state-of-the-art of correlation optics and showing synergetics between the theoretical background and experimental techniques....

  17. Ternary optical computer principle

    Institute of Scientific and Technical Information of China (English)

    金翊; 何华灿; 吕养天

    2003-01-01

    The fundamental principle and the characteristics of ternary optical computer, using horizontal polarized light, vertical polarized light and no-intensity to express information, are propounded in thispaper. The practicability to make key parts of the ternary optical computer from modern micro or integrated optical devices, opto-electronic and electro-photonic elements is discussed. The principle can be applied in three-state optical fiber communication via horizontal and vertical polarized light.

  18. Advanced digital optical communications

    CERN Document Server

    Binh, Le Nguyen

    2015-01-01

    This book provides a fundamental understanding of digital communication applications in optical communication technologies. Emphasizing operation principles versus mathematical analysis, the Second Edition includes new coverage of superchannel optical transmission systems, metropolitan and long-haul optical systems and networks, and Nyquist pulse shaping and high spectral efficiency of optical transmission systems, as well as new homework problems and examples. Featuring theoretical foundations as well as practical case studies, the text focuses on enhancements to digital technologies that are

  19. Autoantibody standardization in The Netherlands.

    NARCIS (Netherlands)

    Damoiseaux, J.; Tervaert, J.W.; Derksen, R.; Hamann, D.; Hooijkaas, H.; Klasen, I.S.; Kallenberg, C.; Limburg, P.; Smeenk, R.

    2009-01-01

    Several initiatives have been undertaken, independent of the European Autoantibody Standardization Initiative (EASI), to standardize autoantibodies in The Netherlands. The Dutch EASI team has made an inventory of which initiatives on autoantibody standardization are already available and what future

  20. Non_standard Wood

    DEFF Research Database (Denmark)

    Tamke, Martin

    Non-Standard elements in architecture bear the promise of a better more specific performance (Oosterhuis 2003). A new understanding of design evolves, which is focusing on open ended approaches, able to negotiate between shifting requirements and to integrate knowledge on process and material......- and machine industry we fabricated a 1:1 demonstrator show casing the potential for performance due to digital fabrication in this sustainable material. The production of a custom made design tool helped not only to explore design variations while keeping up the link to digital production machinery....... Using parametric design tools and computer controlled production facilities Copenhagens Centre for IT and Architecture undertook a practice based research into performance based non-standard element design and mass customization techniques. In close cooperation with wood construction software...

  1. Beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Peskin, M.E.

    1997-05-01

    These lectures constitute a short course in ``Beyond the Standard Model`` for students of experimental particle physics. The author discusses the general ideas which guide the construction of models of physics beyond the Standard model. The central principle, the one which most directly motivates the search for new physics, is the search for the mechanism of the spontaneous symmetry breaking observed in the theory of weak interactions. To illustrate models of weak-interaction symmetry breaking, the author gives a detailed discussion of the idea of supersymmetry and that of new strong interactions at the TeV energy scale. He discusses experiments that will probe the details of these models at future pp and e{sup +}e{sup {minus}} colliders.

  2. 3G Standards

    DEFF Research Database (Denmark)

    Saugstrup, Dan; Henten, Anders

    2006-01-01

    angles – technology, markets and economy, policy and regulation, and other social aspects. Findings – The paper concludes that WCDMA will dominate the markets, but that there will be a co-existence of different solutions – also inside individual countries where more than one solution is implemented......Purpose – The main purpose of this paper is to analyze which standard/technology will win the 3G mobile markets. In addition, two sub topics are examined. First, which kind of victory will it be – will one technological solution be all-dominating or is co-existence more likely? Second, which...... are the most decisive factors in the battle between the different standards – which roles do respectively technology path-dependence, network effects and strategic concerns play? Design/methodology/approach – The approach taken in the paper is to examine the different kinds of stakeholders – in this field...

  3. The Genomic Standards Consortium.

    Directory of Open Access Journals (Sweden)

    Dawn Field

    2011-06-01

    Full Text Available A vast and rich body of information has grown up as a result of the world's enthusiasm for 'omics technologies. Finding ways to describe and make available this information that maximise its usefulness has become a major effort across the 'omics world. At the heart of this effort is the Genomic Standards Consortium (GSC, an open-membership organization that drives community-based standardization activities, Here we provide a short history of the GSC, provide an overview of its range of current activities, and make a call for the scientific community to join forces to improve the quality and quantity of contextual information about our public collections of genomes, metagenomes, and marker gene sequences.

  4. Standarder for god undervisning

    DEFF Research Database (Denmark)

    Dolin, Jens; Christiansen, Frederik V; Troelsen, Rie

    foretages på baggrund af forskningsresultater, og ansattes engagement i undervisning vil ofte være på bekostning af forskningsindsatsen – og dermed på bekostning af vedkommendes akademiske karriere. Dette roundtable vil diskutere hvorvidt indførelsen af standarder for god undervisning kan være en del af en...... indsats, som både kan øge kvaliteten i de videregående uddannelser og øge undervisningens status. En sådan standard kan formuleres på mange måder, som har indflydelse på såvel anvendelighed som på selve forståelsen af hvad god undervisning er. Den udviklede model kan opfattes som et dialogredskab...

  5. Beyond standard quantum chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, S.J.

    1995-09-01

    Despite the many empirical successes of QCD, there are a number of intriguing experimental anomalies that have been observed in heavy flavor hadroproduction, in measurements of azimuthal correlations in deep inelastic processes, and in measurements of spin correlations in hadronic reactions. Such phenomena point to color coherence and multiparton correlations in the hadron wavefunctions and physics beyond standard leading twist factorization. Two new high precision tests of QCD and the Standard Model are discussed: classical polarized photoabsorption sum rules, which are sensitive to anomalous couplings and composite structure, and commensurate scale relations, which relate physical observables to each other without scale or scheme ambiguity. The relationship of anomalous couplings to composite structure is also discussed.

  6. New standards; Neue Normen

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Stephan [Stuttgart Univ. (Germany). Testzentrum fuer Solaranlagen des Inst. fuer Thermodynamik und Waermetechnik (ITW)

    2013-06-06

    At the end of this year (2013) the international collector standard EN ISO 9806 replaces the existing EN 12975-2 standard. Also EN 12975-1, which is formulating the general requirements for solar collectors will be adjusted during the year. And last but not least: the first time boilers and controller can get the label ''Solar Keymark''. [German] Ende dieses Jahres (2013) soll die internationale Kollektornorm EN ISO 9806 die bisherige EN 12975-2 ersetzen. Auch die EN 12975-1, die allgemeine Anforderungen an Solarkollektoren formuliert, wird im Laufe des Jahres angepasst. Und nicht zuletzt: Erstmals koennen Speicher und Regler das Label ''Solar Keymark'' bekommen.

  7. Hypnosis and performance standards.

    Science.gov (United States)

    Lynn, Steven Jay; Green, Joseph P; Jaquith, Leah; Gasior, Donna

    2003-01-01

    Participants received 1 of 3 instructional sets designed to manipulate their performance standards (i.e., criteria used to evaluate hypnotic performance): (a) stringent set (n = 33), these subjects were told that responsive subjects respond immediately to hypnosis and imagine realistically, (b) lenient set (n = 30), these subjects were told that responsive subjects do not necessarily respond immediately or imagine realistically, and (c) control set (n = 34), standard prehypnotic information. As expected, compared to controls, stringent set participants were less responsive to hypnosis, as indexed by measures of actual and estimated suggestibility, subjective involvement, involuntariness, quickness of responding, satisfaction, and imaginative ability. Stringent set participants estimated they passed fewer suggestions, were less satisfied with their performance, and reported less subjective involvement than individuals in the lenient condition.

  8. 76 FR 81295 - Cost Accounting Standards: Cost Accounting Standards 412 and 413-Cost Accounting Standards...

    Science.gov (United States)

    2011-12-27

    ... cost on a current mark-to-market basis better aligns the CAS measurement with current accounting and... 9904 Cost Accounting Standards: Cost Accounting Standards 412 and 413--Cost Accounting Standards... Policy 48 CFR Part 9904 Cost Accounting Standards: Cost Accounting Standards 412 and......

  9. Adaptive optical zoom sensor.

    Energy Technology Data Exchange (ETDEWEB)

    Sweatt, William C.; Bagwell, Brett E.; Wick, David Victor

    2005-11-01

    In order to optically vary the magnification of an imaging system, continuous mechanical zoom lenses require multiple optical elements and use fine mechanical motion to precisely adjust the separations between individual or groups of lenses. By incorporating active elements into the optical design, we have designed and demonstrated imaging systems that are capable of variable optical magnification with no macroscopic moving parts. Changing the effective focal length and magnification of an imaging system can be accomplished by adeptly positioning two or more active optics in the optical design and appropriately adjusting the optical power of those elements. In this application, the active optics (e.g. liquid crystal spatial light modulators or deformable mirrors) serve as variable focal-length lenses. Unfortunately, the range over which currently available devices can operate (i.e. their dynamic range) is relatively small. Therefore, the key to this concept is to create large changes in the effective focal length of the system with very small changes in the focal lengths of individual elements by leveraging the optical power of conventional optical elements surrounding the active optics. By appropriately designing the optical system, these variable focal-length lenses can provide the flexibility necessary to change the overall system focal length, and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses.

  10. Integrated Optical Sensors

    NARCIS (Netherlands)

    Lambeck, Paul; Hoekstra, Hugo

    2003-01-01

    The optical (tele-) communication is the main driving force for the worldwide R&D on integrated optical devices and microsystems. lO-sensors have to compete with many other sensor types both within the optical domain (fiber sensors) and outside that domain, where sensors based on measurand induced c

  11. Integrated Optical Sensors

    NARCIS (Netherlands)

    Lambeck, Paul V.; Hoekstra, Hugo

    2003-01-01

    The optical (tele-) communication is the main driving force for the worldwide R&D on integrated optical devices and microsystems. lO-sensors have to compete with many other sensor types both within the optical domain (fiber sensors) and outside that domain, where sensors based on measurand induced c

  12. Optical Disk Technology.

    Science.gov (United States)

    Abbott, George L.; And Others

    1987-01-01

    This special feature focuses on recent developments in optical disk technology. Nine articles discuss current trends, large scale image processing, data structures for optical disks, the use of computer simulators to create optical disks, videodisk use in training, interactive audio video systems, impacts on federal information policy, and…

  13. Progress in optics

    CERN Document Server

    Wolf, Emil

    2015-01-01

    The Progress in Optics series contains more than 300 review articles by distinguished research workers, which have become permanent records for many important developments, helping optical scientists and optical engineers stay abreast of their fields. Comprehensive, in-depth reviewsEdited by the leading authority in the field

  14. Integrated Optics Some Aspects

    Directory of Open Access Journals (Sweden)

    R. Hradaynath

    1990-01-01

    Full Text Available Status of some key individual integrated optics components, their application in the field of telecommunications, integrated optoelectronic circuits, fibre optics sensors, optical interconnects and logic devices are highlighted in this paper. Possibilities of opto-opto processors in the computers field are also outlined.

  15. Forestry Standardization & Forestry Insurance

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Forestry insurance of our country has developed slowly,of which the main difficulty lies in predicting and determining forestry risk,confirming the sum insured,raising the premiums, indemnity for property loss,coordinating forestry insurance and forestry protection,and lack of insurance legal system etc.With the implementation of forestry's standardized project,and overcoming effectively the technological obstacle existing in forestry's insurance,the development speed of forestry's insurance will be accelerated too.

  16. Standard interface file handbook

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, A.; Huria, H.C. (Cincinnati Univ., OH (United States))

    1992-10-01

    This handbook documents many of the standard interface file formats that have been adopted by the US Department of Energy to facilitate communications between and portability of, various large reactor physics and radiation transport software packages. The emphasis is on those files needed for use of the VENTURE/PC diffusion-depletion code system. File structures, contents and some practical advice on use of the various files are provided.

  17. DOE standard: Firearms safety

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    Information in this document is applicable to all DOE facilities, elements, and contractors engaged in work that requires the use of firearms as provided by law or contract. The standard in this document provides principles and practices for implementing a safe and effective firearms safety program for protective forces and for non-security use of firearms. This document describes acceptable interpretations and methods for meeting Order requirements.

  18. All-optical pseudorandom bit sequences generator based on TOADs

    Science.gov (United States)

    Sun, Zhenchao; Wang, Zhi; Wu, Chongqing; Wang, Fu; Li, Qiang

    2016-03-01

    A scheme for all-optical pseudorandom bit sequences (PRBS) generator is demonstrated with optical logic gate 'XNOR' and all-optical wavelength converter based on cascaded Tera-Hertz Optical Asymmetric Demultiplexer (TOADs). Its feasibility is verified by generation of return-to-zero on-off keying (RZ-OOK) 263-1 PRBS at the speed of 1 Gb/s with 10% duty radio. The high randomness of ultra-long cycle PRBS is validated by successfully passing the standard benchmark test.

  19. Research on Encryption Mechanism of Ethernet Passive Optical Network

    Institute of Scientific and Technical Information of China (English)

    XU Wei-liang; FAN hong

    2006-01-01

    An ethernet-passive-optical-network consists of one optical-line-terminator and multiple optical-network-units oith passive optical components. The network is susceptible to variable security threats. In this paper we propose a security model and an encryption layer placed at reconciliation sublayer. We also propose advanced encryption standard as an ideal cipher algorithm to encrypt downstream data . We then discuss three different methods to solve the problem of the last plaintext group, and the methods are realized on digital signal processing. Finally, we study efficiency and delay issues of the three methods.

  20. CALBC silver standard corpus.

    Science.gov (United States)

    Rebholz-Schuhmann, Dietrich; Jimeno Yepes, Antonio José; Van Mulligen, Erik M; Kang, Ning; Kors, Jan; Milward, David; Corbett, Peter; Buyko, Ekaterina; Beisswanger, Elena; Hahn, Udo

    2010-02-01

    The CALBC initiative aims to provide a large-scale biomedical text corpus that contains semantic annotations for named entities of different kinds. The generation of this corpus requires that the annotations from different automatic annotation systems be harmonized. In the first phase, the annotation systems from five participants (EMBL-EBI, EMC Rotterdam, NLM, JULIE Lab Jena, and Linguamatics) were gathered. All annotations were delivered in a common annotation format that included concept identifiers in the boundary assignments and that enabled comparison and alignment of the results. During the harmonization phase, the results produced from those different systems were integrated in a single harmonized corpus ("silver standard" corpus) by applying a voting scheme. We give an overview of the processed data and the principles of harmonization--formal boundary reconciliation and semantic matching of named entities. Finally, all submissions of the participants were evaluated against that silver standard corpus. We found that species and disease annotations are better standardized amongst the partners than the annotations of genes and proteins. The raw corpus is now available for additional named entity annotations. Parts of it will be made available later on for a public challenge. We expect that we can improve corpus building activities both in terms of the numbers of named entity classes being covered, as well as the size of the corpus in terms of annotated documents.

  1. Standards for medical educators.

    Science.gov (United States)

    Purcell, Nigel; Lloyd-Jones, Gaynor

    2003-02-01

    In the current UK socio-political climate of mounting regulation of professional practice, a debate on the topic of standards amongst medical teachers seems timely. The role of teacher is increasingly recognised as a core professional activity for all doctors and one that cannot be left to chance, aptitude or inclination. As a consequence, faculties have developed a plethora of teacher training programmes for medical teachers. But what is good medical teaching? Unless we know what it is, how can we develop it? One possible approach is to develop clear and comprehensive standards, defining what we mean by competent or effective clinical teaching. In this article we have evaluated and compared two models of standards for clinical educators. The first is the outcome-based approach developed at Dundee Medical School and the second is the scholarship model devised initially by Boyer and then elaborated by Glassick and Fincher et al. The key features of both models are briefly described and their comparative strengths and problematic aspects explored. Both models offer interesting and stimulating ideas and together they provide an instructive contrast. They make a valuable contribution to the ongoing process of improving the provision of medical education.

  2. The Conformal Standard Model

    CERN Document Server

    Latosinski, Adam; Meissner, Krzysztof A; Nicolai, Hermann

    2015-01-01

    We present an extended version of the Conformal Standard Model (characterized by the absence of any new intermediate scales between the electroweak scale and the Planck scale) with an enlarged scalar sector coupling to right-chiral neutrinos in such a way that the scalar potential and the Yukawa couplings involving only right-chiral neutrinos are invariant under a new global symmetry SU(3)$_N$ which is broken explicitly only by the Yukawa interaction coupling right-chiral neutrinos and the electroweak lepton doublets. We point out four main advantages of such an enlargement, namely: (1) the economy of the (non-supersymmetric) Standard Model, and thus its observational success, is preserved; (2) thanks to the enlarged scalar sector the RG improved one-loop effective potential is everywhere positive with a stable global minimum, thereby avoiding the notorious instability of the Standard Model vacuum; (3) the pseudo-Goldstone bosons resulting from spontaneous breaking of the SU(3)$_N$ symmetry are natural Dark M...

  3. Implementing PAT with Standards

    Science.gov (United States)

    Chandramohan, Laakshmana Sabari; Doolla, Suryanarayana; Khaparde, S. A.

    2016-02-01

    Perform Achieve Trade (PAT) is a market-based incentive mechanism to promote energy efficiency. The purpose of this work is to address the challenges inherent to inconsistent representation of business processes, and interoperability issues in PAT like cap-and-trade mechanisms especially when scaled. Studies by various agencies have highlighted that as the mechanism evolves including more industrial sectors and industries in its ambit, implementation will become more challenging. This paper analyses the major needs of PAT (namely tracking, monitoring, auditing & verifying energy-saving reports, and providing technical support & guidance to stakeholders); and how the aforesaid reasons affect them. Though current technologies can handle these challenges to an extent, standardization activities for implementation have been scanty for PAT and this work attempts to evolve them. The inconsistent modification of business processes, rules, and procedures across stakeholders, and interoperability among heterogeneous systems are addressed. This paper proposes the adoption of specifically two standards into PAT, namely Business Process Model and Notation for maintaining consistency in business process modelling, and Common Information Model (IEC 61970, 61968, 62325 combined) for information exchange. Detailed architecture and organization of these adoptions are reported. The work can be used by PAT implementing agencies, stakeholders, and standardization bodies.

  4. Standard biological parts knowledgebase.

    Science.gov (United States)

    Galdzicki, Michal; Rodriguez, Cesar; Chandran, Deepak; Sauro, Herbert M; Gennari, John H

    2011-02-24

    We have created the Knowledgebase of Standard Biological Parts (SBPkb) as a publically accessible Semantic Web resource for synthetic biology (sbolstandard.org). The SBPkb allows researchers to query and retrieve standard biological parts for research and use in synthetic biology. Its initial version includes all of the information about parts stored in the Registry of Standard Biological Parts (partsregistry.org). SBPkb transforms this information so that it is computable, using our semantic framework for synthetic biology parts. This framework, known as SBOL-semantic, was built as part of the Synthetic Biology Open Language (SBOL), a project of the Synthetic Biology Data Exchange Group. SBOL-semantic represents commonly used synthetic biology entities, and its purpose is to improve the distribution and exchange of descriptions of biological parts. In this paper, we describe the data, our methods for transformation to SBPkb, and finally, we demonstrate the value of our knowledgebase with a set of sample queries. We use RDF technology and SPARQL queries to retrieve candidate "promoter" parts that are known to be both negatively and positively regulated. This method provides new web based data access to perform searches for parts that are not currently possible.

  5. Standard biological parts knowledgebase.

    Directory of Open Access Journals (Sweden)

    Michal Galdzicki

    Full Text Available We have created the Knowledgebase of Standard Biological Parts (SBPkb as a publically accessible Semantic Web resource for synthetic biology (sbolstandard.org. The SBPkb allows researchers to query and retrieve standard biological parts for research and use in synthetic biology. Its initial version includes all of the information about parts stored in the Registry of Standard Biological Parts (partsregistry.org. SBPkb transforms this information so that it is computable, using our semantic framework for synthetic biology parts. This framework, known as SBOL-semantic, was built as part of the Synthetic Biology Open Language (SBOL, a project of the Synthetic Biology Data Exchange Group. SBOL-semantic represents commonly used synthetic biology entities, and its purpose is to improve the distribution and exchange of descriptions of biological parts. In this paper, we describe the data, our methods for transformation to SBPkb, and finally, we demonstrate the value of our knowledgebase with a set of sample queries. We use RDF technology and SPARQL queries to retrieve candidate "promoter" parts that are known to be both negatively and positively regulated. This method provides new web based data access to perform searches for parts that are not currently possible.

  6. ISO 50001 Energy Management Standard

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-08-12

    This powerful standard from the International Organization for Standardization (ISO) provides an internationally recognized framework for organizations to voluntarily implement an energy management system.

  7. ESDIS Standards Office (ESO): Requirements, Standards and Practices

    Science.gov (United States)

    Mitchell, Andrew E.; Mcinerney, Mark Allen; Enloe, Yonsok K.; Conover, Helen T.; Doyle, Allan

    2016-01-01

    The ESDIS Standards Office assists the ESDIS Project in formulating standards policy for NASA Earth Science Data Systems (ESDS), coordinates standards activities within ESDIS, and provides technical expertise and assistance with standards related tasks within the NASA Earth Science Data System Working Groups (ESDSWG). This poster summarizes information found on the earthdata.nasa.gov site that describes the ESO.

  8. Optics and optical instruments an introduction

    CERN Document Server

    Johnson, B K

    2011-01-01

    This book illustrates basic practical applications of optical principle. Working models of telescopes, microscopes, photographic lenses, and optical projection systems are diagrammed and explained in full, as are the basic experiments for determining accuracy, power, angular field of view, amount of aberration, and all other necessary facts about the instrument. Throughout the book, only elementary mathematics is used, for the benefit of the student and the beginner in the field of optics.The author, an assistant professor at the Imperial College of Science and Technology in London, shows ho

  9. Enabling inter- and intra-chip optical wireless interconnect by the aid of hybrid plasmonic leaky-wave optical antennas

    Science.gov (United States)

    Ebrahimi, Vahid; Yousefi, Leila; Mohammad-Taheri, Mahmoud

    2017-01-01

    In this paper, we propose a new method to provide optical link in Photonic Integrated Circuits (PICs). The proposed method uses two hybrid plasmonic leaky-wave optical antennas, operating at the standard optical telecommunication wavelength of 1.55 μm, to provide inter-chip interconnect between two layers in a photonic chip and also intra-chip interconnect between two different photonic ICs. Linearly tapered couplers are designed to couple the optical signal from the silicon waveguide to the hybrid plasmonic antennas. The performance of the proposed optical link is verified using numerical full wave simulation. The proposed structure is planar, and can be fabricated using standard CMOS technology which makes it the superior candidate for realization of future multi-layered Photonic Integrated Circuits.

  10. Optical Flashes Preceding GRBs

    CERN Document Server

    Paczynski, B

    2001-01-01

    Only one optical flash associated with a gamma-ray burst has been detected so far by ROTSE. There are also upper limits obtained by several groups for several bursts. Recent model calculations indicate a possibility that optical flash may precede the GRB. Such flashes are undetectable in the currently popular observing mode, with optical instruments responding to GRB triggers. There is a need to develop all sky optical monitoring system capable of recognizing flashes in real time, and more powerful instruments that could respond robotically to optical triggers and carry out follow up observations.

  11. Optical modulator including grapene

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  12. Paraxial Ray Optics Cloaking

    CERN Document Server

    Choi, Joseph S

    2014-01-01

    Despite much interest and progress in optical spatial cloaking, a three-dimensional (3D), transmitting, continuously multidirectional cloak in the visible regime has not yet been demonstrated. Here we experimentally demonstrate such a cloak using ray optics, albeit with some edge effects. Our device requires no new materials, uses isotropic off-the-shelf optics, scales easily to cloak arbitrarily large objects, and is as broadband as the choice of optical material, all of which have been challenges for current cloaking schemes. In addition, we provide a concise formalism that quantifies and produces perfect optical cloaks in the small-angle (`paraxial') limit, and must be satisfied by any good cloaks.

  13. Progress in optics

    CERN Document Server

    Wolf, Emil

    1977-01-01

    In the thirty-seven years that have gone by since the first volume of Progress in Optics was published, optics has become one of the most dynamic fields of science. At the time of inception of this series, the first lasers were only just becoming operational, holography was in its infancy, subjects such as fiber optics, integrated optics and optoelectronics did not exist and quantum optics was the domain of only a few physicists. The term photonics had not yet been coined. Today these fields are flourishing and have become areas of specialisation for many science and engineering students and n

  14. Optic disc oedema

    DEFF Research Database (Denmark)

    Nielsen, Marianne Kromann; Hamann, Steffen

    2014-01-01

    Optic disc oedema describes the nonspecific, localized swelling of the optic nerve head regardless of aetiology. Therefore, differentiating among the various aetiologies depends on a thorough history and knowledge of the clinical characteristics of the underlying conditions. Papilloedema strictly...... refers to optic disc oedema as a consequence of elevated intracranial pressure. It is usually a bilateral condition and visual function is preserved until late. Optic disc oedema caused by an anterior optic neuropathy is usually unilateral and accompanied by the loss of visual function....

  15. [Adaptive optics for ophthalmology].

    Science.gov (United States)

    Saleh, M

    2016-04-01

    Adaptive optics is a technology enhancing the visual performance of an optical system by correcting its optical aberrations. Adaptive optics have already enabled several breakthroughs in the field of visual sciences, such as improvement of visual acuity in normal and diseased eyes beyond physiologic limits, and the correction of presbyopia. Adaptive optics technology also provides high-resolution, in vivo imaging of the retina that may eventually help to detect the onset of retinal conditions at an early stage and provide better assessment of treatment efficacy.

  16. Optics in aircraft engines

    Science.gov (United States)

    Vachon, James; Malhotra, Subhash

    The authors describe optical IR&D (independent research and development) programs designed to demonstrate and evaluate optical technologies for incorporation into next-generation military and commercial aircraft engines. Using a comprehensive demonstration program to validate this technology in an on-engine environment, problems encountered can be resolved early and risk can be minimized. In addition to specific activities related to the optics demonstration on the fighter engine, there are other optical programs underway, including a solenoid control system, a light off detection system, and an optical communication link. Research is also underway in simplifying opto-electronics and exploiting multiplexing to further reduce cost and weight.

  17. Magneto-optical metamaterial

    CERN Document Server

    Sadatgol, Mehdi; Forati, Ebrahim; Levy, Miguel; Guney, Durdu O

    2015-01-01

    We propose a new class of metamaterials called magneto-optical metamaterials that offer enhanced angle of rotation in polarization compared to bulk magneto-optical materials. In the proposed approach, the permittivity tensor of a magneto-optical material is tailored by embedded wire meshes behaving as artificial plasma. We have shown that the angle of rotation in the magneto-optical metamaterial can be enhanced up to 9 times compared to bulk magneto-optical material alone while the polarization extinction ratio remains below -20dB and insertion loss is less than 1.5dB.

  18. Small scale optics

    CERN Document Server

    Yupapin, Preecha

    2013-01-01

    The behavior of light in small scale optics or nano/micro optical devices has shown promising results, which can be used for basic and applied research, especially in nanoelectronics. Small Scale Optics presents the use of optical nonlinear behaviors for spins, antennae, and whispering gallery modes within micro/nano devices and circuits, which can be used in many applications. This book proposes a new design for a small scale optical device-a microring resonator device. Most chapters are based on the proposed device, which uses a configuration know as a PANDA ring resonator. Analytical and nu

  19. Progress in optics

    CERN Document Server

    Wolf, Emil

    2006-01-01

    In the thirty-seven years that have gone by since the first volume of Progress in Optics was published, optics has become one of the most dynamic fields of science. At the time of inception of this series, the first lasers were only just becoming operational, holography was in its infancy, subjects such as fiber optics, integrated optics and optoelectronics did not exist and quantum optics was the domain of only a few physicists. The term photonics had not yet been coined. Today these fields are flourishing and have become areas of specialisation for many science and engineering students and n

  20. Consistency Across Standards or Standards in a New Business Model

    Science.gov (United States)

    Russo, Dane M.

    2010-01-01

    Presentation topics include: standards in a changing business model, the new National Space Policy is driving change, a new paradigm for human spaceflight, consistency across standards, the purpose of standards, danger of over-prescriptive standards, a balance is needed (between prescriptive and general standards), enabling versus inhibiting, characteristics of success-oriented standards, characteristics of success-oriented standards, and conclusions. Additional slides include NASA Procedural Requirements 8705.2B identifies human rating standards and requirements, draft health and medical standards for human rating, what's been done, government oversight models, examples of consistency from anthropometry, examples of inconsistency from air quality and appendices of government and non-governmental human factors standards.

  1. Driver Code for Adaptive Optics

    Science.gov (United States)

    Rao, Shanti

    2007-01-01

    A special-purpose computer code for a deformable-mirror adaptive-optics control system transmits pixel-registered control from (1) a personal computer running software that generates the control data to (2) a circuit board with 128 digital-to-analog converters (DACs) that generate voltages to drive the deformable-mirror actuators. This program reads control-voltage codes from a text file, then sends them, via the computer s parallel port, to a circuit board with four AD5535 (or equivalent) chips. Whereas a similar prior computer program was capable of transmitting data to only one chip at a time, this program can send data to four chips simultaneously. This program is in the form of C-language code that can be compiled and linked into an adaptive-optics software system. The program as supplied includes source code for integration into the adaptive-optics software, documentation, and a component that provides a demonstration of loading DAC codes from a text file. On a standard Windows desktop computer, the software can update 128 channels in 10 ms. On Real-Time Linux with a digital I/O card, the software can update 1024 channels (8 boards in parallel) every 8 ms.

  2. Threshold temperature optical fibre sensors

    Science.gov (United States)

    Stasiewicz, K. A.; Musial, J. E.

    2016-12-01

    This paper presents a new approach to manufacture a threshold temperature sensor based on a biconical optical fibre taper. The presented sensor employs the influence of variable state of concentration of some isotropic materials like wax or paraffin. Application of the above- mentioned materials is an attempt to prove that there is a possibility to obtain a low-cost, repeatable and smart sensor working as an in-line element. Optical fibre taper was obtained from a standard single mode fibre (SMF28®) by using a low pressure gas burner technique. The diameter of the manufactured tapers was 6.0 ± 0.5 μm with the length of elongation equal to 30.50 ± 0.16 mm. The applied technology allowed to produce tapers with the losses of 0.183 ± 0.015 dB. Application of materials with different temperature transition points made it possible to obtain the threshold work at the temperatures connected directly with their conversion temperature. External materials at the temperatures above their melting points do not influence the propagation losses. For each of them two types of the protection area and position of the optical fibre taper were applied.

  3. Design of distributed Raman temperature sensing system based on single-mode optical fiber

    Institute of Scientific and Technical Information of China (English)

    Ziheng XU; Deming LIU; Hairong LIU; Qizhen SUN; Zhifeng SUN; Xu ZHANG; Wengang WANG

    2009-01-01

    The distributed optical fiber temperature sensor system based on Raman scattering has developed rapidly since it was invented in 1970s. The optical wavelengths used in most of the distributed temperature optical fiber sensor system based on the Raman scattering are around from 840 to 1330 nm, and the system operates with multimode optical fibers. However, this wavelength range is not suitable for long-distance transmission due to the high attenuation and dispersion of the transmission optical fiber. A novel distributed optical fiber Raman temperature sensor system based on standard single-mode optical fiber is proposed. The system employs the wavelength of 1550 nm as the probe light and the standard communication optical fiber as the sensing medium to increase the sensing distance. This system mainly includes three modules: the probe light transmitting module, the light magnifying and transmission module, and the signal acquisition module.

  4. [Aspheric optics: physical fundamentals].

    Science.gov (United States)

    Mrochen, M; Büeler, M

    2008-03-01

    Especially regarding intraocular lenses and refractive corneal surgery, one finds numerous concepts on how to improve the optical quality of the human eye through aspheric optics. Aspheric optics consists of optical surfaces in which at least one surface (for example, the corneal surface) deviates from the spherical shape. An aspheric (that is, not spherical) surface enables the correction of aberrations, especially the spherical aberration, by freely shaping the optical surface. The optical aberrations of the human eye can theoretically be minimized through the use of aspheric optics; however, the results are always affected by the optical properties of the cornea and the lens. Aspheric intraocular lenses allow a reduction of postoperative spherical aberrations of the patient's eye, but an optimal individualized conformation can result only when the shape of the cornea (asphericity) is considered. By the same token, the ideal corneal asphericity after refractive surgery for an individual eye cannot be defined without knowing the optical properties of the intraocular structure. Theoretical observations of aspheric optics in refractive surgery show that with aspheric approaches, a higher optical quality for the human eye can be attained. These theoretical advantages must, however, prove themselves in everyday clinical routine.

  5. Optical system design

    CERN Document Server

    Fischer, Robert F

    2008-01-01

    Honed for more than 20 years in an SPIE professional course taught by renowned optical systems designer Robert E. Fischer, Optical System Design, Second Edition brings you the latest cutting-edge design techniques and more than 400 detailed diagrams that clearly illustrate every major procedure in optical design. This thoroughly updated resource helps you work better and faster with computer-aided optical design techniques, diffractive optics, and the latest applications, including digital imaging, telecommunications, and machine vision. No need for complex, unnecessary mathematical derivations-instead, you get hundreds of examples that break the techniques down into understandable steps. For twenty-first century optical design without the mystery, the authoritative Optical Systems Design, Second Edition features: Computer-aided design use explained through sample problems Case studies of third-millennium applications in digital imaging, sensors, lasers, machine vision, and more New chapters on optomechanic...

  6. Optic nerve oxygenation

    DEFF Research Database (Denmark)

    Stefánsson, Einar; Pedersen, Daniella Bach; Jensen, Peter Koch

    2005-01-01

    at similar levels of perfusion pressure. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. The risk for progressive optic nerve atrophy in human...... glaucoma patients is six times higher at a perfusion pressure of 30 mmHg, which corresponds to a level where the optic nerve is hypoxic in experimental animals, as compared to perfusion pressure levels above 50 mmHg where the optic nerve is normoxic. Medical intervention can affect optic nerve oxygen......-oxygenase inhibitor, indomethacin, which indicates that prostaglandin metabolism plays a role. Laboratory studies suggest that carbonic anhydrase inhibitors might be useful for medical treatment of optic nerve and retinal ischemia, potentially in diseases such as glaucoma and diabetic retinopathy. However, clinical...

  7. Nonlinear optical systems

    CERN Document Server

    Lugiato, Luigi; Brambilla, Massimo

    2015-01-01

    Guiding graduate students and researchers through the complex world of laser physics and nonlinear optics, this book provides an in-depth exploration of the dynamics of lasers and other relevant optical systems, under the umbrella of a unitary spatio-temporal vision. Adopting a balanced approach, the book covers traditional as well as special topics in laser physics, quantum electronics and nonlinear optics, treating them from the viewpoint of nonlinear dynamical systems. These include laser emission, frequency generation, solitons, optically bistable systems, pulsations and chaos and optical pattern formation. It also provides a coherent and up-to-date treatment of the hierarchy of nonlinear optical models and of the rich variety of phenomena they describe, helping readers to understand the limits of validity of each model and the connections among the phenomena. It is ideal for graduate students and researchers in nonlinear optics, quantum electronics, laser physics and photonics.

  8. Optical clock networks

    Science.gov (United States)

    Riehle, Fritz

    2017-01-01

    Within the last decade, optical atomic clocks have surpassed the best cesium clocks, which are used to realize the unit of time and frequency, in terms of accuracy and stability by about two orders of magnitude. When remote optical atomic clocks are connected by links without degradation in the clock signals, an optical clock network is formed, with distinct advantages for the dissemination of time, geodesy, astronomy and basic and applied research. Different approaches for time and frequency transfer in the microwave and optical regime, via satellites and free-space links, optical fibre links, or transportable optical atomic clocks, can be used to form a hybrid clock network that may allow a future redefinition of the unit of time based on an optical reference transition.

  9. Optical Robotics in Mesoscopia

    DEFF Research Database (Denmark)

    Glückstad, Jesper

    2012-01-01

    of optical forces and optical torques that, in turn, requires optimization of the underlying light-matter interactions. The requirement of having tightly focused beams in optical tweezer systems exemplifies the need for optimal light-shaping in optical trapping. On the other hand, the recently demonstrated......With light’s miniscule momentum, shrinking robotics down to the micro-scale regime creates opportunities for exploiting optical forces and torques in advanced actuation and control at the nano- and micro-scale dimensions. Advancing light-driven nano- or micro-robotics requires the optimization...... optical lift or light foil shows that optical manipulation can be achieved, even by using unshaped light, and instead applying an appropriately shaped structure. Hence, a generic approach for optimizing lightmatter interaction will involve the combination of optimal light-shaping techniques with the use...

  10. MEMS optical sensor

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to an all-optical sensor utilizing effective index modulation of a waveguide and detection of a wavelength shift of reflected light and a force sensing system accommodating said optical sensor. One embodiment of the invention relates to a sensor system comprising...... at least one multimode light source, one or more optical sensors comprising a multimode sensor optical waveguide accommodating a distributed Bragg reflector, at least one transmitting optical waveguide for guiding light from said at least one light source to said one or more multimode sensor optical...... waveguides, a detector for measuring light reflected from said Bragg reflector in said one or more multimode sensor optical waveguides, and a data processor adapted for analyzing variations in the Bragg wavelength of at least one higher order mode of the reflected light....

  11. Optic nerve oxygenation

    DEFF Research Database (Denmark)

    Stefánsson, Einar; Pedersen, Daniella Bach; Jensen, Peter Koch;

    2005-01-01

    at similar levels of perfusion pressure. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. The risk for progressive optic nerve atrophy in human...... glaucoma patients is six times higher at a perfusion pressure of 30 mmHg, which corresponds to a level where the optic nerve is hypoxic in experimental animals, as compared to perfusion pressure levels above 50 mmHg where the optic nerve is normoxic. Medical intervention can affect optic nerve oxygen......-oxygenase inhibitor, indomethacin, which indicates that prostaglandin metabolism plays a role. Laboratory studies suggest that carbonic anhydrase inhibitors might be useful for medical treatment of optic nerve and retinal ischemia, potentially in diseases such as glaucoma and diabetic retinopathy. However, clinical...

  12. Beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Lykken, Joseph D.; /Fermilab

    2010-05-01

    'BSM physics' is a phrase used in several ways. It can refer to physical phenomena established experimentally but not accommodated by the Standard Model, in particular dark matter and neutrino oscillations (technically also anything that has to do with gravity, since gravity is not part of the Standard Model). 'Beyond the Standard Model' can also refer to possible deeper explanations of phenomena that are accommodated by the Standard Model but only with ad hoc parameterizations, such as Yukawa couplings and the strong CP angle. More generally, BSM can be taken to refer to any possible extension of the Standard Model, whether or not the extension solves any particular set of puzzles left unresolved in the SM. In this general sense one sees reference to the BSM 'theory space' of all possible SM extensions, this being a parameter space of coupling constants for new interactions, new charges or other quantum numbers, and parameters describing possible new degrees of freedom or new symmetries. Despite decades of model-building it seems unlikely that we have mapped out most of, or even the most interesting parts of, this theory space. Indeed we do not even know what is the dimensionality of this parameter space, or what fraction of it is already ruled out by experiment. Since Nature is only implementing at most one point in this BSM theory space (at least in our neighborhood of space and time), it might seem an impossible task to map back from a finite number of experimental discoveries and measurements to a unique BSM explanation. Fortunately for theorists the inevitable limitations of experiments themselves, in terms of resolutions, rates, and energy scales, means that in practice there are only a finite number of BSM model 'equivalence classes' competing at any given time to explain any given set of results. BSM phenomenology is a two-way street: not only do experimental results test or constrain BSM models, they also suggest

  13. Resonance spectra of diabolo optical antenna arrays

    Science.gov (United States)

    Guo, Hong; Simpkins, Blake; Caldwell, Joshua D.; Guo, Junpeng

    2015-10-01

    A complete set of diabolo optical antenna arrays with different waist widths and periods was fabricated on a sapphire substrate by using a standard e-beam lithography and lift-off process. Fabricated diabolo optical antenna arrays were characterized by measuring the transmittance and reflectance with a microscope-coupled FTIR spectrometer. It was found experimentally that reducing the waist width significantly shifts the resonance to longer wavelength and narrowing the waist of the antennas is more effective than increasing the period of the array for tuning the resonance wavelength. Also it is found that the magnetic field enhancement near the antenna waist is correlated to the shift of the resonance wavelength.

  14. Resonance spectra of diabolo optical antenna arrays

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hong; Guo, Junpeng, E-mail: guoj@uah.edu [Department of Electrical and Computer Engineering, University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, AL 35899 (United States); Simpkins, Blake; Caldwell, Joshua D. [Naval Research Laboratory, 4555 Overlook Ave., SW Washington, DC 20375 (United States)

    2015-10-15

    A complete set of diabolo optical antenna arrays with different waist widths and periods was fabricated on a sapphire substrate by using a standard e-beam lithography and lift-off process. Fabricated diabolo optical antenna arrays were characterized by measuring the transmittance and reflectance with a microscope-coupled FTIR spectrometer. It was found experimentally that reducing the waist width significantly shifts the resonance to longer wavelength and narrowing the waist of the antennas is more effective than increasing the period of the array for tuning the resonance wavelength. Also it is found that the magnetic field enhancement near the antenna waist is correlated to the shift of the resonance wavelength.

  15. Spontaneous natural optical activity in disordered media

    CERN Document Server

    Pinheiro, F A; Papasimakis, N; Zheludev, N I

    2016-01-01

    We demonstrate natural optical activity in disordered ensembles of non-chiral plasmonic resonators. We show that the statistical distributions of rotatory power and spatial dichroism are strongly dependent on the scattering mean free path in diffusive random media. This result is explained in terms of the intrinsic geometric chirality of disordered media, as they lack mirror symmetry. We argue that chirality and natural optical activity of disordered systems can be quantified by the standard deviation of both rotatory power and spatial dichroism. Our results are based on microscopic electromagnetic wave transport theory coupled to vectorial Green's matrix method for pointlike scatterers, and are independently confirmed by full-wave simulations.

  16. Controllable parabolic-cylinder optical rogue wave.

    Science.gov (United States)

    Zhong, Wei-Ping; Chen, Lang; Belić, Milivoj; Petrović, Nikola

    2014-10-01

    We demonstrate controllable parabolic-cylinder optical rogue waves in certain inhomogeneous media. An analytical rogue wave solution of the generalized nonlinear Schrödinger equation with spatially modulated coefficients and an external potential in the form of modulated quadratic potential is obtained by the similarity transformation. Numerical simulations are performed for comparison with the analytical solutions and to confirm the stability of the rogue wave solution obtained. These optical rogue waves are built by the products of parabolic-cylinder functions and the basic rogue wave solution of the standard nonlinear Schrödinger equation. Such rogue waves may appear in different forms, as the hump and paw profiles.

  17. Viewpoints on Grid Standards

    Institute of Scientific and Technical Information of China (English)

    Andrew A. Chien; Xian-He Sun; Zhi-Wei Xu

    2005-01-01

    @@ At GCC 2003 in Shanghai in December 2003, a panel discussion was held on the future of grid computing and on the role of the Globus Toolkit in future grid standards. Panelists include Andrew Chien (UCSD, USA), Wolfgang Gentzsch (Sun),Francis Lau (HKU, China), Carl Kesselman (USC, USA), Satoshi Matsuoka (TIT, Japan), Xian-He Sun (IIT, USA), Richard Wirt (Intel), Liang-Jie Zhang (IBM Research), Song-Nian Zhou (Platform Computing), and Zhi-Wei Xu (ICT, China), with Hai Jin (HUST, China) served as the coordinator. The panel talks were stimulating and well received. Three of the panel talk notes are selected and included in this viewpoint.

  18. Hazard Communication Standard

    Energy Technology Data Exchange (ETDEWEB)

    Sichak, S.

    1991-01-01

    The current rate of technological advances has brought with it an overwhelming increase in the usage of chemicals in the workplace and in the home. Coupled to this increase has been a heightened awareness in the potential for acute and chronic injuries attributable to chemical insults. The Hazard Communication Standard has been introduced with the desired goal of reducing workplace exposures to hazardous substances and thereby achieving a corresponding reduction in adverse health effects. It was created and proclaimed by the US Department of Labor and regulated by the Occupational Safety and Health Administration. 1 tab.

  19. Fractional standard map

    Energy Technology Data Exchange (ETDEWEB)

    Edelman, Mark, E-mail: edelman@cims.nyu.ed [Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, NY 10012 (United States)] [Department of Physics, Stern College at Yeshiva University, 245 Lexington Avenue, New York, NY 10016 (United States); Tarasov, Vasily E. [Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, NY 10012 (United States)] [Skobeltsyn Institute of Nuclear Physics, Moscow State University, Moscow 119991 (Russian Federation)

    2009-12-28

    Properties of the phase space of the standard map with memory are investigated. This map was obtained from a kicked fractional differential equation. Depending on the value of the map parameter and the fractional order of the derivative in the original differential equation, this nonlinear dynamical system demonstrates attractors (fixed points, stable periodic trajectories, slow converging and slow diverging trajectories, ballistic trajectories, and fractal-like structures) and/or chaotic trajectories. At least one type of fractal-like sticky attractors in the chaotic sea was observed.

  20. World gravity standards

    Science.gov (United States)

    Uotila, U. A.

    1978-01-01

    In order to use gravity anomalies in geodetic computations and geophysical interpretations, the observed gravity values from which anomalies are derived should be referred to one consistent world wide system. The International Gravity Standardization Net 1971 was adapted by the International Union of Geodesy and Geophysics at Moscow in 1971, the network was result of extensive cooperation by many organizations and individuals around the world. The network contains more than 1800 stations around the world. The data used in the adjustment included more than 25,000 gravimetry, pendulum and absolute measurements.

  1. Non-standard antennas

    CERN Document Server

    Le Chevalier, Francois; Staraj, Robert

    2013-01-01

    This book aims at describing the wide variety of new technologies and concepts of non-standard antenna systems - reconfigurable, integrated, terahertz, deformable, ultra-wideband, using metamaterials, or MEMS,  etc, and how they open the way to a wide range of applications, from personal security and communications to multifunction radars and towed sonars, or satellite navigation systems, with space-time diversity on transmit and receive. A reference book for designers  in this lively scientific community linking antenna experts and signal processing engineers.

  2. High Availability Electronics Standards

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, R.S.; /SLAC

    2006-12-13

    Availability modeling of the proposed International Linear Collider (ILC) predicts unacceptably low uptime with current electronics systems designs. High Availability (HA) analysis is being used as a guideline for all major machine systems including sources, utilities, cryogenics, magnets, power supplies, instrumentation and controls. R&D teams are seeking to achieve total machine high availability with nominal impact on system cost. The focus of this paper is the investigation of commercial standard HA architectures and packaging for Accelerator Controls and Instrumentation. Application of HA design principles to power systems and detector instrumentation are also discussed.

  3. Government by standards

    DEFF Research Database (Denmark)

    Triantafillou, Peter

    2016-01-01

    Since 2009, all Danish hospitals have been subjected to a comprehensive, mandatory accreditation system, the so-called Danish Quality Model (DDKM), in order to assure the quality of hospital services. So far there is no evidence of DDKM’s positive effects on clinical outcome and it may even be co......, it is argued that the accreditation system is hard to refuse because it promises to increase the quality of hospital services and, more importantly, because the procedural standards espoused by DDKM work through the structured and accountable freedom of medical staff....

  4. Emergency Management Standards and Schools

    Science.gov (United States)

    National Clearinghouse for Educational Facilities, 2009

    2009-01-01

    This publication discusses emergency management standards for school use and lists standards recommended by FEMA's National Incident Management System (NIMS). Schools are encouraged to review these standards carefully and to adopt, where applicable, those that meet their needs. The lists of standards, resources, and references contained herein…

  5. Spillover effects of international standards

    DEFF Research Database (Denmark)

    Trifkovic, Neda

    Most studies focus on trade effects and organizational outcomes of international standards, neglecting the effect of standards on employees. Using a two-year matched firm–employee panel dataset, this paper finds that the application of standards improves work conditions in small and medium....... The study reveals unexpected benefits from certification, calling for higher investment in standards....

  6. Fiber optic to integrated optical chip coupler

    Science.gov (United States)

    Pikulski, Joseph I. (Inventor); Ramer, O. Glenn (Inventor)

    1987-01-01

    Optical fibers are clamped by a block onto a substrate. Thereupon, metal is plated over the fibers to hold them in place upon the substrate. The clamp block is removed and the opening, resulting from the clamp block's presence, is then plated in. The built-up metallic body is a coupling which holds the fibers in position so that the ends can be polished for coupling to an integrated optical chip upon a coupling fixture.

  7. Spillover effects of international standards

    DEFF Research Database (Denmark)

    Trifkovic, Neda

    Most studies focus on trade effects and organizational outcomes of international standards, neglecting the effect of standards on employees. Using a two-year matched firm–employee panel dataset, this paper finds that the application of standards improves work conditions in small and medium enterp....... The study reveals unexpected benefits from certification, calling for higher investment in standards.......Most studies focus on trade effects and organizational outcomes of international standards, neglecting the effect of standards on employees. Using a two-year matched firm–employee panel dataset, this paper finds that the application of standards improves work conditions in small and medium...

  8. International round-robin experiment to test the International Organization for Standardization total-scattering draft standard.

    Science.gov (United States)

    Kadkhoda, P; Müller, A; Ristau, D; Duparré, A; Gliech, S; Lauth, H; Schuhmann, U; Reng, N; Tilsch, M; Schuhmann, R; Amra, C; Deumie, C; Jolie, C; Kessler, H; Lindström, T; Ribbing, C G; Bennett, J M

    2000-07-01

    An international round-robin experiment has been conducted among laboratories in different countries to test the measurement and the data-analysis procedures in the International Organization for Standardization draft standard ISO/DIS 13696 for measuring total scattering from low-scatter laser optics. Ten laboratories measured total backscattering from high-reflectance mirrors, 50% beam splitters, and antireflection-coated windows. Results were sent to the Laser Zentrum Hannover, which acted as coordinator and analyzed all the backscattering data. The results showed that the procedure in the draft standard was useful for measuring and reporting backscattering for low-scatter optics. Problems encountered in the round-robin experiment included the accumulation of particles on the surfaces, particularly on the high-reflectance mirrors.

  9. Aperiodic Volume Optics

    Science.gov (United States)

    Gerke, Tim D.

    Presented in this thesis is an investigation into aperiodic volume optical devices. The three main topics of research and discussion are the aperiodic volume optical devices that we call computer-generated volume holograms (CGVH), defects within periodic 3D photonic crystals, and non-periodic, but ordered 3D quasicrystals. The first of these devices, CGVHs, are designed and investigated numerically and experimentally. We study the performance of multi-layered amplitude computer-generated volume holograms in terms of efficiency and angular/frequency selectivity. Simulation results show that such aperiodic devices can increase diffraction efficiency relative to periodic amplitude volume holograms while maintaining angular and wavelength selectivity. CGVHs are also designed as voxelated volumes using a new projection optimization algorithm. They are investigated using a volumetric diffraction simulation and a standard 3D beam propagation technique as well as experimentally. Both simulation and experiment verify that the structures function according to their design. These represent the first diffractive structures that have the capacity for generating arbitrary transmission and reflection wave fronts and that provide the ability for multiplexing arbitrary functionality given different illumination conditions. Also investigated and discussed in this thesis are 3D photonic crystals and quasicrystals. We demonstrate that these devices can be fabricated using a femtosecond laser direct writing system that is particularly appropriate for fabrication of such arbitrary 3D structures. We also show that these devices can provide 3D partial bandgaps which could become complete bandgaps if fabricated using high index materials or by coating lower index materials with high index metals. Our fabrication method is particularly suited to the fabrication of engineered defects within the periodic or quasi-periodic systems. We demonstrate the potential for fabricating defects within

  10. DETERMINATION OF OPTICAL LOSSES AT FIBERS JOINING WITH DIFFERENT MODEFIELD DIAMETER

    Directory of Open Access Journals (Sweden)

    A. V. Varlamov

    2013-03-01

    Full Text Available For optical losses reducing at fiber optic systems creation the angular distribution of the output radiation of birefringent optical fibers with elliptical stress cladding with 4, 12, 16 and 18 mol. % GeO2 is measured. Obtained data make it possible to predict losses at joining of optical fibers with elliptical stress cladding and different concentrations of GeO2 with each other, as well as standard telecom fibers, such as SMF-28, other birefringent optical fibers and integrated optics components.

  11. Optical-Thermal Response of Laser-Irradiated Tissue

    CERN Document Server

    Welch, Ashley J

    2011-01-01

    The second edition of 'Optical-Thermal Response of Laser-Irradiated Tissue' maintains the standard of excellence established in the first edition, while adjusting the content to reflect changes in tissue optics and medical applications since 1995. The material concerning light propagation now contains new chapters devoted to electromagnetic theory for coherent light. The material concerning thermal laser-tissue interactions contains a new chapter on pulse ablation of tissue. The medical applications section now includes several new chapters on Optical Coherent Tomography, acoustic imaging, molecular imaging, forensic optics and nerve stimulation. A detailed overview is provided of the optical and thermal response of tissue to laser irradiation along with diagnostic and therapeutic examples including fiber optics. Sufficient theory is included in the book so that it is suitable for a one or two semester graduate or for senior elective courses. Material covered includes: 1. light propagation and diagnostic appl...

  12. Steering optical comb frequency by rotating polarization state

    CERN Document Server

    Zhang, Y; Zhang, X F; Zhang, L; Han, W; Guo, W; Jiang, H; Zhang, S

    2016-01-01

    Optical frequency combs, with precise control of repetition rate and carrier-envelope-offset frequency, have revolutionized many fields, such as fine optical spectroscopy, optical frequency standards, ultra-fast science research, ultra-stable microwave generation and precise ranging measurement. However, existing high bandwidth frequency control methods have small dynamic range, requiring complex hybrid control techniques. To overcome this limitation, we develop a new approach, where a home-made intra-cavity electro-optic modulator tunes polarization state of laser signal rather than only optical length of the cavity, to steer frequencies of a nonlinear-polarization-rotation mode-locked laser. By taking advantage of birefringence of the whole cavity, this approach results in not only broadband but also relative large-dynamic frequency control. Experimental results show that frequency control dynamic range increase at least one order in comparison with the traditional intra-cavity electro-optic modulator techn...

  13. Standardized Referente Evapotranspiration Equation

    Directory of Open Access Journals (Sweden)

    M.D. Mundo–Molina

    2009-04-01

    Full Text Available In this paper is presented a discussion on the necessity to standardize the Penman–Monteith equations in order to estimate ETo. The proposal is to define an accuracy and standarize equation based in Penman–Monteith. The automated weather station named CIANO (27° 22 ' 144 North latitude and 109" 55' west longitude it was selected tomake comparisons. The compared equations we re: a CIANO weat her station, b Penman–Monteith ASCE (PMA, Penman–Monteith FAO 56 (PM FAO 56, Penman–Monteith estandarizado ASCE (PM Std. ASCE. The results were: a There are important differences between PMA and CIANO weather station. The differences are attributed to the nonstandardization of the equation CIANO weather station, b The coefficient of correlation between both methods was of 0,92, with a standard deviation of 1,63 mm, an average quadratic error of 0,60 mm and one efficiency in the estimation of ETo with respect to the method pattern of 87%.

  14. Standarder for god undervisning

    DEFF Research Database (Denmark)

    Dolin, Jens; Christiansen, Frederik V; Troelsen, Rie;

    foretages på baggrund af forskningsresultater, og ansattes engagement i undervisning vil ofte være på bekostning af forskningsindsatsen – og dermed på bekostning af vedkommendes akademiske karriere. Dette roundtable vil diskutere hvorvidt indførelsen af standarder for god undervisning kan være en del af en...... indsats, som både kan øge kvaliteten i de videregående uddannelser og øge undervisningens status. En sådan standard kan formuleres på mange måder, som har indflydelse på såvel anvendelighed som på selve forståelsen af hvad god undervisning er. Den udviklede model kan opfattes som et dialogredskab...... for undervisningsudvikling, men kan også frygtes at blive brugt som et kontrolredskab. Disse forskellige muligheder og dilemmaer vil blive adresseret i samtalen. Oplægsholderne vil tage udgangspunkt i initiativer de er engagerede i på deres egne universiteter og fremhæve de konkrete problemer, som disse initiativer har...

  15. New standard exceeds expectations

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, M.J. (Environmental Data Resources Inc., Southport, CT (United States))

    1993-08-01

    The new ASTM environmental due diligence standard is delivering far more than expected when it was conceived in 1990. Its use goes well beyond the relatively narrow legal liability protection that was the primary goal in its development. The real estate industry, spearheaded by the lending community, was preoccupied with environmental risk and liability. Lenders throughout the concept's evolution have been at the forefront in defining environmental due diligence. The lender liability rule is intended to protect property owners from CERCLA liability for property they own or companies they manage (for example, as a result of foreclosure). The new site assessment standard increasingly is considered a benchmark for prudent environmental due diligence in the interest of risk management, not legal liability. The focus on risk management, including collateral devaluation and corporate credit risk, are becoming dominant areas of policy focus in the lending industry. Lenders now are revising their policies to incorporate transactions beyond issues of real estate, in which a company's economic viability and ability to service debt could be impacted by an environmental problem unrelated to property transfers.

  16. The Supersymmetric Standard Model

    Science.gov (United States)

    Fayet, Pierre

    2016-10-01

    The Standard Model may be included within a supersymmetric theory, postulating new sparticles that differ by half-a-unit of spin from their standard model partners, and by a new quantum number called R-parity. The lightest one, usually a neutralino, is expected to be stable and a possible candidate for dark matter. The electroweak breaking requires two doublets, leading to several charged and neutral Brout-Englert-Higgs bosons. This also leads to gauge/Higgs unification by providing extra spin-0 partners for the spin-1 W± and Z. It offers the possibility to view, up to a mixing angle, the new 125 GeV boson as the spin-0 partner of the Z under two supersymmetry transformations, i.e. as a Z that would be deprived of its spin. Supersymmetry then relates two existing particles of different spins, in spite of their different gauge symmetry properties, through supersymmetry transformations acting on physical fields in a non-polynomial way. We also discuss how the compactification of extra dimensions, relying on R-parity and other discrete symmetries, may determine both the supersymmetrybreaking and grand-unification scales.

  17. The Supersymmetric Standard Model

    CERN Document Server

    Fayet, Pierre

    2016-01-01

    The Standard Model may be included within a supersymmetric theory, postulating new sparticles that differ by half-a-unit of spin from their standard model partners, and by a new quantum number called R-parity. The lightest one, usually a neutralino, is expected to be stable and a possible candidate for dark matter. The electroweak breaking requires two doublets, leading to several charged and neutral Brout- Englert-Higgs bosons. This also leads to gauge/Higgs unification by providing extra spin-0 partners for the spin-1 W$^\\pm$ and Z. It offers the possibility to view, up to a mixing angle, the new 125 GeV boson as the spin-0 partner of the Z under two supersymmetry transformations, i.e. as a Z that would be deprived of its spin. Supersymmetry then relates two existing particles of different spins, in spite of their different gauge symmetry properties, through supersymmetry transformations acting on physical fields in a non-polynomial way. We also discuss how the compactification of extra dimensions, relying ...

  18. Measuring against clinical standards.

    Science.gov (United States)

    Shaw, Charles D

    2003-07-15

    Systematic improvement of health services requires the objective measurement of people, practices and organisations against valid and explicit standards in order to identify and implement appropriate change. Effective quality systems must embrace a wide range of definitions of quality, and a similar variety of approaches to defining, measuring and improving. Clinical performance may be examined from three professional viewpoints--clinical competence: assessment of individual practitioners against explicit criteria to recognise achievement and to promote continuing development. Traditional mechanisms of training, registration and accreditation enable clinicians to reach career grades but responsibility for subsequent support is often unclear between employers, professions and registering bodies. Clinical practice: assessment of actual clinical process and outcomes against research-based "best practice" to identify and reduce variation. Peer review, clinical audit and confidential enquiries are examples of this approach, which may involve single or multiple professional groups and their interface with management. Service accreditation: systems to assess health care organisations against published standards in order to encourage best management practice. These are usually run on a regional or national basis and, though sensitive to expectations of patients, managers, clinicians, paying agencies and government, they are usually managed by an impartial but authoritative organisation.

  19. Scatter From Optical Components: An Overview

    Science.gov (United States)

    Stover, John C.

    1990-01-01

    Although optical scatter is a source of noise, limits resolution and reduces system throughput, it is also an extremely sensitive metrology tool and is being employed in a wide variety of applications both in and out of the optics industry. This paper is intended as a brief review of the current state of this important technology as it emerges from university and government laboratories to more general industry use. The bidirectional scatter distribution function (or BSDF) has become the common format for expressing scatter data and is now used almost universally. Measurements are routinely made at several laboratories around the country from the UV to the mid-IR. Data analysis of optical component scatter has progressed to the point where a variety of analysis tools are becoming available for discriminating between the various sources of scatter. Work has progressed on the analysis of rough surface scatter and the application of these techniques to some challenging problems outside the optical industry. Scatter metrology is acquiring standards and formal test procedures. The available scatter data base is rapidly expanding as the number and sophistication of measurement facilities increases. Scatter from contaminants, which is a key issue for space optics, is continuing to be a major area of work as scatterometers appear in vacuum chambers at various laboratories across the country. The current flurry of work in this growing area of metrology can be expected to continue for several more years and expand to applications outside the optics industry.

  20. Honeywell optical investigations on FLASH program

    Science.gov (United States)

    O'Rourke, Ken; Peterson, Eric; Yount, Larry

    1995-05-01

    The increasing performance and reduction of life cycle cost requirements placed on commercial and military transport aircraft are resulting in more complex, highly integrated aircraft control and management systems. The use of fiber optic data transmission media can make significant contributions in achieving these performance and cost goals. The Honeywell portion of Task 2A on the Fly-by-Light Advanced System Hardware (FLASH) program is evaluating a Primary Flight Control System (PFCS) using pilot and copilot inputs from Active Hand Controllers (AHC) which are optically linked to the primary flight Control Computers (PFCC). Customer involvement is an important element of the Task 2A activity. Establishing customer requirements and perspectives on productization of systems developed under FLASH are key to future product success. The Honeywell elements of the PFCS demonstrator provide a command path that is optically interfaced from crew inputs to commands of distributed, smart actuation subsystems commands. Optical communication architectures are implemented using several protocols including the new AS-1773A 20 Mbps data bus standard. The interconnecting fiber optic cable plant is provided by our Task 1A teammate McDonnell Douglas Aerospace (West). Fiber optic cable plant fabrication uses processed, tools and materials reflecting necessary advances in manufacturing required to make fly-by-light avionics systems marketable.

  1. Practice Oriented Master's in Optics

    Science.gov (United States)

    Dimmock, John O.

    1998-01-01

    The development of an interdisciplinary Masters Program with a concentration in Optics and Photonics Technology has been is described. This program was developed under the U.S. Manufacturing Education and Training Activity of the Technology Reinvestment Project. This development was a collaboration between the University of Alabama in Huntsville (UAH), Alabama A&M University, Northwest Shoals Community College, the NASA Marshall Space Flight Center (MSFC), the U.S. Army Missile Command, Oak Ridge National Laboratory (ORNL), Advanced Optical Systems Inc., Dynetics, Inc., Hughes Danbury Optical Systems, Inc., Nichols Research and Speedring Inc. These organizations as well as the National Institute for Standards and Technology and SCI, Inc. have been participating fully in the design, development and implementation of this program. This goal of the program is to produce highly trained graduates who can also solve practical problems. To this end, the program includes an on-site practicum at a manufacturing location. The broad curriculum of this program emphasizes the fundamentals of optics, optical systems manufacturing and testing, and the principles of design and manufacturing to cost for commercial products. The Master's of Science (MS) in Physics and Master's of Science in Engineering (MSE) in Electrical Engineering Degrees with concentration in Optics and Photonics Technology are offered by the respective UAH academic departments with support from and in consultation with a Steering Committee composed of representatives from each of the participating organizations, and a student representative from UAH. The origins of the programs are described. The curricula of the programs is described. The course outlines of the new courses which were developed for the new curriculum are included. Also included are samples of on-site practicums which the students have been involved in. Also included as attachments are samples of the advertisements, which includes flyers, and

  2. Standardization Promotes Midea Industrial Upgrading

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    1.Midea Achievenents in standardization For a long time,Midea attaches high importance to the implementation of standardization.After four decades development,Midea has accumulated advantages in manufacturing,technology,market and personnel to some extent,which form Midea's strategic foundation of enterprise standardization.In 2006,the Group set up the Science & Technology Management Department,enhanced the standardization management function to the Group and made standardization management the more specialized and systemized.

  3. Fibre-optical microendoscopy.

    Science.gov (United States)

    Gu, M; Bao, H; Kang, H

    2014-04-01

    Microendoscopy has been an essential tool in exploring micro/nano mechanisms in vivo due to high-quality imaging performance, compact size and flexible movement. The investigations into optical fibres, micro-scanners and miniature lens have boosted efficiencies of remote light delivery to sample site and signal collection. Given the light interaction with materials in the fluorescence imaging regime, this paper reviews two classes of compact microendoscopy based on a single fibre: linear optical microendoscopy and nonlinear optical microendoscopy. Due to the fact that fluorescence occurs only in the focal volume, nonlinear optical microendoscopy can provide stronger optical sectioning ability than linear optical microendoscopy, and is a good candidate for deep tissue imaging. Moreover, one-photon excited fluorescence microendoscopy as the linear optical microendoscopy suffers from severe photobleaching owing to the linear dependence of photobleaching rate on excitation laser power. On the contrary, nonlinear optical microendoscopy, including two-photon excited fluorescence microendoscopy and second harmonic generation microendoscopy, has the capability to minimize or avoid the photobleaching effect at a high excitation power and generate high image contrast. The combination of various nonlinear signals gained by the nonlinear optical microendoscopy provides a comprehensive insight into biophenomena in internal organs. Fibre-optical microendoscopy overcomes physical limitations of traditional microscopy and opens up a new path to achieve early cancer diagnosis and microsurgery in a minimally invasive and localized manner.

  4. Direct optical to microwave conversion

    Science.gov (United States)

    Taylor, Henry F.

    1990-09-01

    Support of high frequency fiber optic links through development of innovative higher efficiency techniques to convert optical energy directly to RF Energy. Control of Phases Arrays by optical means in an area of expanding technology development. Fiber optics and other forms of optical waveguide can provide greater accuracy and true time delay in a phase delay network. Methods of improvement in transfer of optical energy to RF Energy are determined. Development of Direct Optical-to-RF-Direct Amplifiers will result in higher efficiency, low noise, optical receivers for fiber optic links with improved performance. This results in longer fiber optic links without repeaters and improved BER or shorter links.

  5. Study on optical attenuation performance of special stock power optical cable based on a wind induced vibration environment in laboratory

    Science.gov (United States)

    Li, Jie; Zhao, Ziyuan

    2010-08-01

    For the purpose of 10G communication system upgrade for Guangdong Power Grid, laboratory simulation tests on dynamic and temperature cycle are performed for the reserved cables (stock optical cables) of existing 2.5G special optical cable lines that have operated for ten years, in order to verify the possibility of optical cable to be upgraded to a 10G transmission level and evaluate the degradation level of optical cables. This paper points out the necessity of laboratory test on attenuation performance in a wind-induced vibration environment, describes the test methods thereof, summarizes and analyzes a variety of optical attenuation performance data, and finds that the attenuation performance of current OPGW, ADSS, ADL optical fiber lines in wind-induced vibration environment meets the industry standards.

  6. Optical to microwave clock frequency ratios with a nearly continuous strontium optical lattice clock

    CERN Document Server

    Lodewyck, Jérôme; Bookjans, Eva; Robyr, Jean-Luc; Shi, Chunyan; Vallet, Grégoire; Targat, Rodolphe Le; Nicolodi, Daniele; Coq, Yann Le; Guéna, Jocelyne; Abgrall, Michel; Rosenbusch, Peter; Bize, Sébastien

    2016-01-01

    Optical lattice clocks are at the forefront of frequency metrology. Both the instability and systematic uncertainty of these clocks have been reported to be two orders of magnitude smaller than the best microwave clocks. For this reason, a redefinition of the SI second based on optical clocks seems possible in the near future. However, the operation of optical lattice clocks has not yet reached the reliability that microwave clocks have achieved so far. In this paper, we report on the operation of a strontium optical lattice clock that spans several weeks, with more than 80% uptime. We make use of this long integration time to demonstrate a reproducible measurement of frequency ratios between the strontium clock transition and microwave Cs primary and Rb secondary frequency standards.

  7. Optical changes in cortical tissue during seizure activity using optical coherence tomography (Conference Presentation)

    Science.gov (United States)

    Ornelas, Danielle; Hasan, Md.; Gonzalez, Oscar; Krishnan, Giri; Szu, Jenny I.; Myers, Timothy; Hirota, Koji; Bazhenov, Maxim; Binder, Devin K.; Park, Boris H.

    2017-02-01

    Epilepsy is a chronic neurological disorder characterized by recurrent and unpredictable seizures. Electrophysiology has remained the gold standard of neural activity detection but its resolution and high susceptibility to noise and motion artifact limit its efficiency. Optical imaging techniques, including fMRI, intrinsic optical imaging, and diffuse optical imaging, have also been used to detect neural activity yet these techniques rely on the indirect measurement of changes in blood flow. A more direct optical imaging technique is optical coherence tomography (OCT), a label-free, high resolution, and minimally invasive imaging technique that can produce depth-resolved cross-sectional and 3D images. In this study, OCT was used to detect non-vascular depth-dependent optical changes in cortical tissue during 4-aminopyridine (4-AP) induced seizure onset. Calculations of localized optical attenuation coefficient (µ) allow for the assessment of depth-resolved volumetric optical changes in seizure induced cortical tissue. By utilizing the depth-dependency of the attenuation coefficient, we demonstrate the ability to locate and remove the optical effects of vasculature within the upper regions of the cortex on the attenuation calculations of cortical tissue in vivo. The results of this study reveal a significant depth-dependent decrease in attenuation coefficient of nonvascular cortical tissue both ex vivo and in vivo. Regions exhibiting decreased attenuation coefficient show significant temporal correlation to regions of increased electrical activity during seizure onset and progression. This study allows for a more thorough and biologically relevant analysis of the optical signature of seizure activity in vivo using OCT.

  8. The Diamond Standard Vodka酒

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    对于酒的品味不仅仅在酒本身所散发出的醉人魅力,自古以来,拥有艺术品般精湛做工、华美造犁的盛酒器皿也和酒一样流传千古。The Diamond Standard Vodka以“奢侈”、“豪华”作为卖点,除了散发着北欧风格的高贵气质外,由原产自奥地利的施华洛廿奇水晶制成25mm的瓶身更让它身价倍增。以钻石命名的它使用了钻石过滤专利系统,

  9. Standardization of depression measurement

    DEFF Research Database (Denmark)

    Wahl, Inka; Löwe, Bernd; Bjørner, Jakob

    2014-01-01

    comparisons among included measures. Large differences were found in their measurement precision and range, providing a rationale for instrument selection. Published scale-specific threshold scores of depression severity showed remarkable consistencies across different questionnaires. CONCLUSION: An IRT-based......OBJECTIVES: To provide a standardized metric for the assessment of depression severity to enable comparability among results of established depression measures. STUDY DESIGN AND SETTING: A common metric for 11 depression questionnaires was developed applying item response theory (IRT) methods. Data...... instrument-independent metric for depression severity enables direct comparisons among established measures. The "common ruler" simplifies the interpretation of depression assessment by identifying key thresholds for clinical and epidemiologic decision making and facilitates integrative psychometric research...

  10. Spatial Standard Observer

    Science.gov (United States)

    Watson, Andrew B. (Inventor)

    2012-01-01

    The present invention relates to devices and methods for the measurement and/or for the specification of the perceptual intensity of a visual image, or the perceptual distance between a pair of images. Grayscale test and reference images are processed to produce test and reference luminance images. A luminance filter function is convolved with the reference luminance image to produce a local mean luminance reference image. Test and reference contrast images are produced from the local mean luminance reference image and the test and reference luminance images respectively, followed by application of a contrast sensitivity filter. The resulting images are combined according to mathematical prescriptions to produce a Just Noticeable Difference, JND value, indicative of a Spatial Standard Observer, SSO. Some embodiments include masking functions, window functions, special treatment for images lying on or near borders and pre-processing of test images.

  11. Second order Standard Model

    Directory of Open Access Journals (Sweden)

    Johnny Espin

    2015-06-01

    Full Text Available It is known, though not commonly, that one can describe fermions using a second order in derivatives Lagrangian instead of the first order Dirac one. In this description the propagator is scalar, and the complexity is shifted to the vertex, which contains a derivative operator. In this paper we rewrite the Lagrangian of the fermionic sector of the Standard Model in such second order form. The new Lagrangian is extremely compact, and is obtained from the usual first order Lagrangian by integrating out all primed (or dotted 2-component spinors. It thus contains just half of the 2-component spinors that appear in the usual Lagrangian, which suggests a new perspective on unification. We sketch a natural in this framework SU(2×SU(4⊂SO(9 unified theory.

  12. libdrdc: software standards library

    Science.gov (United States)

    Erickson, David; Peng, Tie

    2008-04-01

    This paper presents the libdrdc software standards library including internal nomenclature, definitions, units of measure, coordinate reference frames, and representations for use in autonomous systems research. This library is a configurable, portable C-function wrapped C++ / Object Oriented C library developed to be independent of software middleware, system architecture, processor, or operating system. It is designed to use the automatically-tuned linear algebra suite (ATLAS) and Basic Linear Algebra Suite (BLAS) and port to firmware and software. The library goal is to unify data collection and representation for various microcontrollers and Central Processing Unit (CPU) cores and to provide a common Application Binary Interface (ABI) for research projects at all scales. The library supports multi-platform development and currently works on Windows, Unix, GNU/Linux, and Real-Time Executive for Multiprocessor Systems (RTEMS). This library is made available under LGPL version 2.1 license.

  13. Standard Operating Procedure

    Science.gov (United States)

    1997-01-01

    l^m .:#,"■• y’’:>’£l’S ABO GROUP CONFIRMED |[ Rh OF .NEGATIVE UNITS CONFIRMED fe^/w’H’o’^Ä^ ■ •:.■.■:•• •■’ .Tv-v^l^.>’-V.^^V’ir;i-.^K-V.^’vV-i...using 0.02 ml of whole blood diluted with 5.98 ml of Drabkin’s reagent (1:251 dilution). 51 I. Measure the supernatant hemoglobin concentration...34NcUiod fef*ɜ 17-0? STANDARD OPERATING PROCEDURE Red Blood Cells Collected in the CPDA-1 800 ml Primary PVC Plastic Bag Collection System and

  14. Microfabricated ion frequency standard

    Science.gov (United States)

    Schwindt, Peter; Biedermann, Grant; Blain, Matthew G.; Stick, Daniel L.; Serkland, Darwin K.; Olsson, III, Roy H.

    2010-12-28

    A microfabricated ion frequency standard (i.e. an ion clock) is disclosed with a permanently-sealed vacuum package containing a source of ytterbium (Yb) ions and an octupole ion trap. The source of Yb ions is a micro-hotplate which generates Yb atoms which are then ionized by a ultraviolet light-emitting diode or a field-emission electron source. The octupole ion trap, which confines the Yb ions, is formed from suspended electrodes on a number of stacked-up substrates. A microwave source excites a ground-state transition frequency of the Yb ions, with a frequency-doubled vertical-external-cavity laser (VECSEL) then exciting the Yb ions up to an excited state to produce fluorescent light which is used to tune the microwave source to the ground-state transition frequency, with the microwave source providing a precise frequency output for the ion clock.

  15. Optical material. Hikari zairyo

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, T.; Sakate, N.; Ueoka, T.; Iwakuni, H. (Mazda Motor Corp., Hiroshima (Japan))

    1990-06-01

    It is obvious that various electronic technologies will be positively adopted in automobiles in the future and optical materials are supporting the above trend greatly. In this article, with regard to the optical materials now adopted in automobiles or those expected to be adopted therein in the future, their principles as well as usage, etc. are outlined. Furthermore, the prospect of the materials in the future is stated. The optical materials selected in this article are as follows: as for optical communications; optical fibers, photo emission/reception components, connecting technologies, and photo switches, etc., concerning materials for display such as meters and instrument panels for automobiles, etc.; liquid crystal, electroluminescent elements, light emitting diodes, and polarization films, with regard to dimmering materials; electrochromism and photochromism, and concerning other optical materials; solar cells, and transparent electroconductive films. 13 refs., 4 figs., 6 tabs.

  16. Entanglement in Classical Optics

    CERN Document Server

    Ghose, Partha

    2013-01-01

    The emerging field of entanglement or nonseparability in classical optics is reviewed, and its similarities with and differences from quantum entanglement clearly pointed out through a recapitulation of Hilbert spaces in general, the special restrictions on Hilbert spaces imposed in quantum mechanics and the role of Hilbert spaces in classical polarization optics. The production of Bell-like states in classical polarization optics is discussed, and new theorems are proved to discriminate between separable and nonseparable states in classical wave optics where no discreteness is involved. The influence of the Pancharatnam phase on a classical Bell-like state is deived. Finally, to what extent classical polarization optics can be used to simulate quantum information processing tasks is also discussed. This should be of great practical importance because coherence and entanglement are robust in classical optics but not in quantum systems.

  17. Advances in integrated optics

    CERN Document Server

    Chester, A; Bertolotti, M

    1994-01-01

    This volwne contains the Proceedings of a two-week summer conference titled "Advances in Integrated Optics" held June 1-9, 1993, in Erice, Sicily. This was the 18th annual course organized by the International School of Quantum Electronics, under the auspices of the "Ettore Majorana" Centre for Scientific Culture. The term Integrated Optics signifies guided-wave optical circuits consisting of two or more devices on a single substrate. Since its inception in the late 1960's, Integrated Optics has evolved from a specialized research topic into a broad field of work, ranging from basic research through commercial applications. Today many devices are available on market while a big effort is devolved to research on integrated nonlinear optical devices. This conference was organized to provide a comprehensive survey of the frontiers of this technology, including fundamental concepts, nonlinear optical materials, devices both in the linear and nonlinear regimes, and selected applications. These Proceedings update a...

  18. Quantum optical waveform conversion

    CERN Document Server

    Kielpinski, D; Wiseman, HM

    2010-01-01

    Currently proposed architectures for long-distance quantum communication rely on networks of quantum processors connected by optical communications channels [1,2]. The key resource for such networks is the entanglement of matter-based quantum systems with quantum optical fields for information transmission. The optical interaction bandwidth of these material systems is a tiny fraction of that available for optical communication, and the temporal shape of the quantum optical output pulse is often poorly suited for long-distance transmission. Here we demonstrate that nonlinear mixing of a quantum light pulse with a spectrally tailored classical field can compress the quantum pulse by more than a factor of 100 and flexibly reshape its temporal waveform, while preserving all quantum properties, including entanglement. Waveform conversion can be used with heralded arrays of quantum light emitters to enable quantum communication at the full data rate of optical telecommunications.

  19. Tunable micro-optics

    CERN Document Server

    Duppé, Claudia

    2015-01-01

    Presenting state-of-the-art research into the dynamic field of tunable micro-optics, this is the first book to provide a comprehensive survey covering a varied range of topics including novel materials, actuation concepts and new imaging systems in optics. Internationally renowned researchers present a diverse range of chapters on cutting-edge materials, devices and subsystems, including soft matter, artificial muscles, tunable lenses and apertures, photonic crystals, and complete tunable imagers. Special contributions also provide in-depth treatment of micro-optical characterisation, scanners, and the use of natural eye models as inspiration for new concepts in advanced optics. With applications extending from medical diagnosis to fibre telecommunications, Tunable Micro-optics equips readers with a solid understanding of the broader technical context through its interdisciplinary approach to the realisation of new types of optical systems. This is an essential resource for engineers in industry and academia,...

  20. Silicon Optical Modulator Simulation

    Directory of Open Access Journals (Sweden)

    Soon Thor LIM

    2015-04-01

    Full Text Available We developed a way of predicting and analyzing high speed optical modulator. Our research adopted a bottom-up approach to consider high-speed optical links using an eye diagram. Our method leverages on modular mapping of electrical characteristics to optical characteristics, while attaining the required accuracy necessary for device footprint approaching sub-micron scales where electrical data distribution varies drastically. We calculate for the bias dependent phase shift (2pi/mm and loss (dB/mm for the optical modulator based on the real and imaginary part of complex effective indices. Subsequently, combine effectively both the electrical and optical profiles to construct the optical eye diagram which is the essential gist of signal integrity of such devices.