Sample records for hgcdte infrared detectors

  1. Can graphene make better HgCdTe infrared detectors?

    Directory of Open Access Journals (Sweden)

    Shi Yanli


    Full Text Available Abstract We develop a simple and low-cost technique based on chemical vapor deposition from which large-size graphene films with 5-10 graphene layers can be produced reliably and the graphene films can be transferred easily onto HgCdTe (MCT thin wafers at room temperature. The proposed technique does not cause any thermal and mechanical damages to the MCT wafers. It is found that the averaged light transmittance of the graphene film on MCT thin wafer is about 80% in the mid-infrared bandwidth at room temperature and 77 K. Moreover, we find that the electrical conductance of the graphene film on the MCT substrate is about 25 times larger than that of the MCT substrate at room temperature and 77 K. These experimental findings suggest that, from a physics point of view, graphene can be utilized as transparent electrodes as a replacement for metal electrodes while producing better and cheaper MCT infrared detectors.

  2. MTF measurement and analysis of linear array HgCdTe infrared detectors (United States)

    Zhang, Tong; Lin, Chun; Chen, Honglei; Sun, Changhong; Lin, Jiamu; Wang, Xi


    The slanted-edge technique is the main method for measurement detectors MTF, however this method is commonly used on planar array detectors. In this paper the authors present a modified slanted-edge method to measure the MTF of linear array HgCdTe detectors. Crosstalk is one of the major factors that degrade the MTF value of such an infrared detector. This paper presents an ion implantation guard-ring structure which was designed to effectively absorb photo-carriers that may laterally defuse between adjacent pixels thereby suppressing crosstalk. Measurement and analysis of the MTF of the linear array detectors with and without a guard-ring were carried out. The experimental results indicated that the ion implantation guard-ring structure effectively suppresses crosstalk and increases MTF value.

  3. Extended short wavelength infrared HgCdTe detectors on silicon substrates (United States)

    Park, J. H.; Hansel, D.; Mukhortova, A.; Chang, Y.; Kodama, R.; Zhao, J.; Velicu, S.; Aqariden, F.


    We report high-quality n-type extended short wavelength infrared (eSWIR) HgCdTe (cutoff wavelength 2.59 μm at 77 K) layers grown on three-inch diameter CdTe/Si substrates by molecular beam epitaxy (MBE). This material is used to fabricate test diodes and arrays with a planar device architecture using arsenic implantation to achieve p-type doping. We use different variations of a test structure with a guarded design to compensate for the lateral leakage current of traditional test diodes. These test diodes with guarded arrays characterize the electrical performance of the active 640 × 512 format, 15 μm pitch detector array.

  4. HgCdTe Avalanche Photodiode Detectors for Airborne and Spaceborne Lidar at Infrared Wavelengths (United States)

    Sun, Xiaoli; Abshire, James B.; Beck, Jeffrey D.; Mitra, Pradip; Reiff, Kirk; Yang, Guangning


    We report results from characterizing the HgCdTe avalanche photodiode (APD) sensorchip assemblies (SCA) developed for lidar at infrared wavelength using the high density vertically integrated photodiodes (HDVIP) technique. These devices demonstrated high quantum efficiency, typically greater than 90 between 0.8 micrometers and the cut-off wavelength, greater than 600 APD gain, near unity excess noise factor, 6-10 MHz electrical bandwidth and less than 0.5 fW/Hz(exp.1/2) noise equivalent power (NEP). The detectors provide linear analog output with a dynamic range of 2-3 orders of magnitude at a fixed APD gain without averaging, and over 5 orders of magnitude by adjusting the APD and preamplifier gain settings. They have been successfully used in airborne CO2 and CH4 integrated path differential absorption (IPDA) lidar as a precursor for space lidar applications.

  5. Status of HgCdTe Barrier Infrared Detectors Grown by MOCVD in Military University of Technology (United States)

    Kopytko, M.; Jóźwikowski, K.; Martyniuk, P.; Gawron, W.; Madejczyk, P.; Kowalewski, A.; Markowska, O.; Rogalski, A.; Rutkowski, J.


    In this paper we present the status of HgCdTe barrier detectors with an emphasis on technological progress in metalorganic chemical vapor deposition (MOCVD) growth achieved recently at the Institute of Applied Physics, Military University of Technology. It is shown that MOCVD technology is an excellent tool for HgCdTe barrier architecture growth with a wide range of composition, donor /acceptor doping, and without post-grown annealing. The device concept of a specific barrier bandgap architecture integrated with Auger-suppression is as a good solution for high-operating temperature infrared detectors. Analyzed devices show a high performance comparable with the state-of-the-art of HgCdTe photodiodes. Dark current densities are close to the values given by "Rule 07" and detectivities of non-immersed detectors are close to the value marked for HgCdTe photodiodes. Experimental data of long-wavelength infrared detector structures were confirmed by numerical simulations obtained by a commercially available software APSYS platform. A detailed analysis applied to explain dark current plots was made, taking into account Shockley-Read-Hall, Auger, and tunneling currents.

  6. Monolithic dual-band HgCdTe infrared detector structure

    CSIR Research Space (South Africa)

    Parish, G


    Full Text Available A monolithic HgCdTe photoconductive device structure is presented that is suitable for dual-band optically registered infrared photodetection in the two atmospheric transmission windows of 3-5 mu m and 8-12 mu m, which correspond to the mid...

  7. Temperature-sensitive junction transformations for mid-wavelength HgCdTe photovoltaic infrared detector arrays by laser beam induced current microscope

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Weicheng [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Hu, Weida, E-mail:; Lin, Tie; Yin, Fei; Zhang, Bo; Chen, Xiaoshuang; Lu, Wei [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Cheng, Xiang' ai, E-mail:; Wang, Rui [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)


    In this paper, we report on the disappearance of the photosensitive area extension effect and the unusual temperature dependence of junction transformation for mid-wavelength, n-on-p HgCdTe photovoltaic infrared detector arrays. The n-type region is formed by B{sup +} ion implantation on Hg-vacancy-doped p-type HgCdTe. Junction transformations under different temperatures are visually captured by a laser beam induced current microscope. A physical model of temperature dependence on junction transformation is proposed and demonstrated by using numerical simulations. It is shown that Hg-interstitial diffusion and temperature activated defects jointly lead to the p-n junction transformation dependence on temperature, and the weaker mixed conduction compared with long-wavelength HgCdTe photodiode contributes to the disappearance of the photosensitive area extension effect in mid-wavelength HgCdTe infrared detector arrays.

  8. Passivation Effect of Atomic Layer Deposition of Al2O3 Film on HgCdTe Infrared Detectors (United States)

    Zhang, Peng; Ye, Zhen-Hua; Sun, Chang-Hong; Chen, Yi-Yu; Zhang, Tian-Ning; Chen, Xin; Lin, Chun; Ding, Ring-Jun; He, Li


    The passivation effect of atomic layer deposition of (ALD) Al2O3 film on a HgCdTe infrared detector was investigated in this work. The passivation effect of Al2O3 film was evaluated by measuring the minority carrier lifetime, capacitance versus voltage ( C- V) characteristics of metal-insulator-semiconductor devices, and resistance versus voltage ( R- V) characteristics of variable-area photodiodes. The minority carrier lifetime, C- V characteristics, and R- V characteristics of HgCdTe devices passivated by ALD Al2O3 film was comparable to those of HgCdTe devices passivated by e-beam evaporation of ZnS/CdTe film. However, the baking stability of devices passivated by Al2O3 film is inferior to that of devices passivated by ZnS/CdTe film. In future work, by optimizing the ALD Al2O3 film growing process and annealing conditions, it may be feasible to achieve both excellent electrical properties and good baking stability.

  9. Uncooled middle wavelength infrared photoconductors based on (111) and (100) oriented HgCdTe (United States)

    Madejczyk, Paweł; Kębłowski, Artur; Gawron, Waldemar; Martyniuk, Piotr; Kopytko, Małgorzata; Stępień, Dawid; Rutkowski, Jarosław; Piotrowski, Józef; Piotrowski, Adam; Rogalski, Antoni


    We present progress in metal organic chemical vapor deposition (MOCVD) growth of (100) HgCdTe epilayers achieved recently at the Institute of Applied Physics, Military University of Technology and Vigo System S.A. It is shown that MOCVD technology is an excellent tool for the fabrication of different HgCdTe detector structures with a wide range of composition, donor/acceptor doping, and without post grown ex-situ annealing. Surface morphology, residual background concentration, and acceptor doping efficiency are compared in (111) and (100) oriented HgCdTe epilayers. At elevated temperatures, the carrier lifetime in measured p-type photoresistors is determined by Auger 7 process with about one order of magnitude difference between theoretical and experimental values. Particular progress has been achieved in the growth of (100) HgCdTe epilayers for medium wavelength infrared photoconductors operated in high-operating temperature conditions.

  10. HgCdTe photovoltaic detectors on Si substrates

    International Nuclear Information System (INIS)

    Zanio, K.R.; Bean, R.C.


    HgCdTe photovoltaic detectors have been fabricated on Si substrates through intermediate CdTe/GaAs layers. Encapsulation of the GaAs between the CdTe and Si prevents unintentional doping of the HgCdTe by Ga and As. Uniform epitaxial GaAs is grown on three inch diameter Si substrates. Detectors on such large area Si substrates will offer hybrid focal plane arrays whose dimensions are not limited by the difference between the coefficients of thermal expansion of the Si signal processor and the substrate for the HgCdTe detector array. The growth of HgCdTe detectors on the Si signal processors for monolithic focal plane arrays is also considered. 40 references

  11. Improved HgCdTe detectors with novel antireflection coating (United States)

    Babu, Sachi R.; Hu, Kelley; Manthripragada, Sridhar; Martineau, Robert J.; Kotecki, C. A.; Peters, F. A.; Burgess, A. S.; Krebs, Danny J.; Mott, David B.; Ewin, Audrey J.; Miles, A.; Nguyen, Trang L.; Shu, Peter K.


    The composite infrared spctrometer (CIRS) is an important instrument for the upcoming Cassini mission for sensing infrared (IR) radiation from the Saturanian planetary system. We have delivered a linear, ten element, mercury cadmium telluride (HgCdTe) photoconductive detector array for use on focal plane 3 (FP3), which is responsible for detecting radiation from the 9.1 micrometer to 16.6 micrometer wavelength range. Reliable HgCdTe detectors require robust passivation, a low-stress zinc sulfide (ZnS) anti-reflection (AR) coating with good adhesion, and a proper optical cavity design to smooth out the resonance in the detector spectral response. During the development of CIRS flight array, we have demonstrated the potential of using an in-situ interfacial layer, such as SiN(subscript x), between ZnS and the anodic oxide. Such an interfacial layer drastically improves the adhesion between the ZnS and oxide, without degrading the minority carrier lifetime. We have also demonstrated the feasibility of applying a SiN(subscript x) 'rain coat' layer over the ZnS to prevent moisture and other chemicals from attacking the AR coating, thus improving the long term reliability. This also enables device operation in a hazardous environment. The alumina/epoxy/HgCdTe/oxide/ZnS structure is a complicated multi-cavity optical system. We have developed an extensive device simulation, which enables us to make the optimal choice of individual cavity thickness for minimizing the resonance and maximizing the quantum efficiency. We have also used 0.05 micrometer alumina powder loaded epoxy to minimize the reflections at the epoxy/HgCdTe interface, thus minimizing the resonance.

  12. HgCdTe e-avalanche photodiode detector arrays

    Directory of Open Access Journals (Sweden)

    Anand Singh


    Full Text Available Initial results on the MWIR e-APD detector arrays with 30 μm pitch fabricated on LPE grown compositionally graded p-HgCdTe epilayers are presented. High dynamic resistance times active area (R0A product 2 × 106 Ω-cm2, low dark current density 4 nA/cm2 and high gain 5500 at -8 V were achieved in the n+-υ-p+ HgCdTe e-APD at 80 K. LPE based HgCdTe e-APD development makes this technology amenable for adoption in the foundries established for the conventional HgCdTe photovoltaic detector arrays without any additional investment.

  13. History of infrared detectors (United States)

    Rogalski, A.


    This paper overviews the history of infrared detector materials starting with Herschel's experiment with thermometer on February 11th, 1800. Infrared detectors are in general used to detect, image, and measure patterns of the thermal heat radiation which all objects emit. At the beginning, their development was connected with thermal detectors, such as thermocouples and bolometers, which are still used today and which are generally sensitive to all infrared wavelengths and operate at room temperature. The second kind of detectors, called the photon detectors, was mainly developed during the 20th Century to improve sensitivity and response time. These detectors have been extensively developed since the 1940's. Lead sulphide (PbS) was the first practical IR detector with sensitivity to infrared wavelengths up to ˜3 μm. After World War II infrared detector technology development was and continues to be primarily driven by military applications. Discovery of variable band gap HgCdTe ternary alloy by Lawson and co-workers in 1959 opened a new area in IR detector technology and has provided an unprecedented degree of freedom in infrared detector design. Many of these advances were transferred to IR astronomy from Departments of Defence research. Later on civilian applications of infrared technology are frequently called "dual-use technology applications." One should point out the growing utilisation of IR technologies in the civilian sphere based on the use of new materials and technologies, as well as the noticeable price decrease in these high cost technologies. In the last four decades different types of detectors are combined with electronic readouts to make detector focal plane arrays (FPAs). Development in FPA technology has revolutionized infrared imaging. Progress in integrated circuit design and fabrication techniques has resulted in continued rapid growth in the size and performance of these solid state arrays.

  14. The development of the room temperature LWIR HgCdTe detectors for free space optics communication systems (United States)

    Martyniuk, Piotr; Gawron, Waldemar; Mikołajczyk, Janusz


    There are many room temperature applications to include free space optics (FSO) communication system combining quantum cascade lasers sources where HgCdTe long-wave (8-12 micrometer) infrared radiation (LWIR) detector reaching ultrafast response time 109 cmHz1/2/W. Since commercially available FSO could operate separately in SWIR, MWIR and LWIR range - the dual band detectors should be implemented into FSO. This paper shows theoretical performance of the dual band back-to-back MWIR and LWIR HgCdTe detector operating at 300 K pointing out the MWIR active layer influence on LWIR operating regime.

  15. Single-Photon-Sensitive HgCdTe Avalanche Photodiode Detector (United States)

    Huntington, Andrew


    The purpose of this program was to develop single-photon-sensitive short-wavelength infrared (SWIR) and mid-wavelength infrared (MWIR) avalanche photodiode (APD) receivers based on linear-mode HgCdTe APDs, for application by NASA in light detection and ranging (lidar) sensors. Linear-mode photon-counting APDs are desired for lidar because they have a shorter pixel dead time than Geiger APDs, and can detect sequential pulse returns from multiple objects that are closely spaced in range. Linear-mode APDs can also measure photon number, which Geiger APDs cannot, adding an extra dimension to lidar scene data for multi-photon returns. High-gain APDs with low multiplication noise are required for efficient linear-mode detection of single photons because of APD gain statistics -- a low-excess-noise APD will generate detectible current pulses from single photon input at a much higher rate of occurrence than will a noisy APD operated at the same average gain. MWIR and LWIR electron-avalanche HgCdTe APDs have been shown to operate in linear mode at high average avalanche gain (M > 1000) without excess multiplication noise (F = 1), and are therefore very good candidates for linear-mode photon counting. However, detectors fashioned from these narrow-bandgap alloys require aggressive cooling to control thermal dark current. Wider-bandgap SWIR HgCdTe APDs were investigated in this program as a strategy to reduce detector cooling requirements.

  16. Performances of a HGCDTE APD Based Detector with Electric Cooling for 2-μm DIAL/IPDA Applications

    Directory of Open Access Journals (Sweden)

    Dumas A.


    Full Text Available In this work we report on design and testing of an HgCdTe Avalanche Photodiode (APD detector assembly for lidar applications in the Short Wavelength Infrared Region (SWIR : 1,5 - 2 μm. This detector consists in a set of diodes set in parallel -making a 200 μm large sensitive area- and connected to a custom high gain TransImpedance Amplifier (TIA. A commercial four stages Peltier cooler is used to reach an operating temperature of 185K. Crucial performances for lidar use are investigated : linearity, dynamic range, spatial homogeneity, noise and resistance to intense illumination.

  17. Recent progress in infrared detector technologies (United States)

    Rogalski, A.


    In the paper, fundamental and technological issues associated with the development and exploitation of the most advanced infrared detector technologies are discussed. In this class of detectors both photon and thermal detectors are considered. Special attention is directed to HgCdTe ternary alloys on silicon, type-II superlattices, uncooled thermal bolometers, and novel uncooled micromechanical cantilever detectors. Despite serious competition from alternative technologies and slower progress than expected, HgCdTe is unlikely to be seriously challenged for high-performance applications, applications requiring multispectral capability and fast response. However, the nonuniformity is a serious problem in the case of LWIR and VLWIR HgCdTe detectors. In this context, it is predicted that type-II superlattice system seems to be an alternative to HgCdTe in long wavelength spectral region. In well established uncooled imaging, microbolometer arrays are clearly the most used technology. Present state-of-the-art microbolometers are based on polycrystalline or amorphous materials, typically vanadium oxide (VO x) or amorphous silicon (α-Si), with only modest temperature sensitivity and noise properties. Basic efforts today are mainly focused on pixel reduction and performance enhancement. Attractive alternatives consist of low-resistance α-SiGe monocrystalline SiGe quantum wells or quantum dots. In spite of successful commercialization of uncooled microbolometers, the infrared community is still searching for a platform for thermal imagers that combine affordability, convenience of operation, and excellent performance. Recent advances in MEMS systems have lead to the development of uncooled IR detectors operating as micromechanical thermal detectors. Between them the most important are biomaterial microcantilevers.

  18. Infrared detectors

    CERN Document Server

    Rogalski, Antonio


    This second edition is fully revised and reorganized, with new chapters concerning third generation and quantum dot detectors, THz detectors, cantilever and antenna coupled detectors, and information on radiometry and IR optics materials. Part IV concerning focal plane arrays is significantly expanded. This book, resembling an encyclopedia of IR detectors, is well illustrated and contains many original references … a really comprehensive book.-F. Sizov, Institute of Semiconductor Physics, National Academy of Sciences, Kiev, Ukraine

  19. A Highly Sensitive Multi-Element HgCdTe E-APD Detector for IPDA Lidar Applications (United States)

    Beck, Jeff; Welch, Terry; Mitra, Pradip; Reiff, Kirk; Sun, Xiaoli; Abshire, James


    An HgCdTe electron avalanche photodiode (e-APD) detector has been developed for lidar receivers, one application of which is integrated path differential absorption lidar measurements of such atmospheric trace gases as CO2 and CH4. The HgCdTe APD has a wide, visible to mid-wave-infrared, spectral response, high dynamic range, substantially improved sensitivity, and an expected improvement in operational lifetime. A demonstration sensor-chip assembly consisting of a 4.3 lm cutoff HgCdTe 4 9 4 APD detector array with 80 micrometer pitch pixels and a custom complementary metal-oxide-semiconductor readout integrated circuit was developed. For one typical array the APD gain was 654 at 12 V with corresponding gain normalized dark currents ranging from 1.2 fA to 3.2 fA. The 4 9 4 detector system was characterized at 77 K with a 1.55 micrometer wavelength, 1 microsecond wide, laser pulse. The measured unit gain detector photon conversion efficiency was 91.1%. At 11 V bias the mean measured APD gain at 77 K was 307.8 with sigma/mean uniformity of 1.23%. The average, noise-bandwidth normalized, system noise-equivalent power (NEP) was 1.04 fW/Hz(exp 1/2) with a sigma/mean of 3.8%. The measured, electronics-limited, bandwidth of 6.8 MHz was more than adequate for 1 microsecond pulse detection. The system had an NEP (3 MHz) of 0.4 fW/Hz(exp 1/2) at 12 V APD bias and a linear dynamic range close to 1000. A gain-independent quantum-limited SNR of 80% of full theoretical was indicative of a gain-independent excess noise factor very close to 1.0 and the expected APD mode quantum efficiency.

  20. Barrier Infrared Detector (BIRD) (United States)

    National Aeronautics and Space Administration — A recent breakthrough in MWIR detector design, has resulted in a high operating temperature (HOT) barrier infrared detector (BIRD) that is capable of spectral...

  1. Radiation response issues for infrared detectors (United States)

    Kalma, Arne H.


    Researchers describe the most important radiation response issues for infrared detectors. In general, the two key degradation mechanisms in infrared detectors are the noise produced by exposure to a flux of ionizing particles (e.g.; trapped electronics and protons, debris gammas and electrons, radioactive decay of neutron-activated materials) and permanent damage produced by exposure to total dose. Total-dose-induced damage is most often the result of charge trapping in insulators or at interfaces. Exposure to short pulses of ionization (e.g.; prompt x rays or gammas, delayed gammas) will cause detector upset. However, this upset is not important to a sensor unless the recovery time is too long. A few detector technologies are vulnerable to neutron-induced displacement damage, but fortunately most are not. Researchers compare the responses of the new technologies with those of the mainstream technologies of PV HgCdTe and IBC Si:As. One important reason for this comparison is to note where some of the newer technologies have the potential to provide significantly improved radiation hardness compared with that of the mainstream technologies, and thus to provide greater motivation for the pursuit of these technologies.

  2. Laboratory Measurement of the Brighter-fatter Effect in an H2RG Infrared Detector


    Plazas, A. A.; Shapiro, C.; Smith, R.; Huff, E.; Rhodes, J.


    The "brighter-fatter" (BF) effect is a phenomenon (originally discovered in charge coupled devices) in which the size of the detector point spread function (PSF) increases with brightness. We present, for the first time, laboratory measurements demonstrating the existence of the effect in a Hawaii-2RG HgCdTe near infrared (NIR) detector. We use the Precision Projector Laboratory, a JPL facility for emulating astronomical observations with UV/VIS/NIR detectors, to project about 17,000 point so...

  3. Ultra-Low Dark Current HgCdTe Detector in SWIR for Space Applications (United States)

    Cervera, C.; Boulade, O.; Gravrand, O.; Lobre, C.; Guellec, F.; Sanson, E.; Ballet, P.; Santailler, J. L.; Moreau, V.; Zanatta, J. P.; Fieque, B.; Castelein, P.


    This paper presents recent developments at Commissariat à l'Energie atomique, Laboratoire d'Electronique et de Technologie de l'Information infrared laboratory on processing and characterization of p-on- n HgCdTe (MCT) planar infrared focal plane arrays (FPAs) in short-wave infrared (SWIR) spectral band for the astrophysics applications. These FPAs have been grown using both liquid phase epitaxy and molecular beam epitaxy on a lattice-matched CdZnTe substrate. This technology exhibits lower dark current and lower series resistance in comparison with n-on- p vacancy-doped architecture and is well adapted for low flux detection or high operating temperature. This architecture has been evaluated for space applications in long-wave infrared and very-long-wave infrared spectral bands with cut-off wavelengths from 10 μm up to 17 μm at 78 K and is now evaluated for the SWIR range. The metallurgical nature of the absorbing layer is also examined and both molecular beam epitaxy and liquid phase epitaxy have been investigated. Electro-optical characterizations have been performed on individual photodiodes from test arrays, whereas dark current investigation has been performed with a fully functional readout integrated circuit dedicated to low flux operations.

  4. Enhanced numerical analysis of three-color HgCdTe detectors (United States)

    Jóźwikowski, K.; Rogalski, A.


    The performance of three-color HgCdTe photovoltaic heterostructure detector is examined theoretically. In comparison with two-color detectors with two back-to-back junctions, three-color structure contain an absorber of intermediate wavelength placed between two junctions, and electronic barriers are used to isolate this intermediate region. This structure was first proposed by British workers. Enhanced original computer programs are applied to solve the system of non-linear continuity equations for carriers and Poisson equations. In addition, the numerical analysis includes the dependence of absorption coefficient on Burstein effect as well as interference effects in heterostructure with metallic electrical contacts. Three detector structures with different localizations of separating barriers are analyzed. The calculations results are presented in the form of spatial distributions of bandgap energy and quantum efficiency. It is shown that the performance of the detector is critically dependent on the barrier's doping level and position in relation to the junction. This behavior is serious disadvantage of the considered three color detector. A small shift of the barrier location and doping level causes serious changes in spectral responsivity.

  5. Numerical analysis of three-colour HgCdTe detectors (United States)

    Jóźwikowski, K.; Rogalski, A.


    The performance of three-colour HgCdTe photovoltaic heterostructure detector is examined theoretically. In comparison with two-colour detectors with two back-to-back junctions, three-colour structure contains an absorber of intermediate wavelength placed between two junctions and electronic barriers are used to isolate this intermediate region. This structure was first proposed by British workers. Three-detector structures with different localizations of separating barriers are analyzed. The calculation results are presented in the form of spatial distributions of bandgap energy and quantum efficiency. Enhanced original computer programs are applied to solve the system of non-linear continuity equations for carriers and Poisson equations. In addition, the numerical analysis includes the dependence of absorption coefficient on Burstein effect as well as interference effects in heterostructure with metallic electrical contacts. It is shown that the performance of the detector is critically dependent on the barrier’s doping level and position in relation to the junction. This behaviour is serious disadvantage of the considered three-colour detector. A small shift of the barrier location and doping level causes serious changes in spectral responsivity.

  6. Active Pixel HgCdTe Detectors With Built-in Dark Current Reduction for Near-Room Temperature Operation, Phase II (United States)

    National Aeronautics and Space Administration — High sensitivity HgCdTe infrared arrays operating at 77K can now be tailored in a wide range of wavelengths from 1 to 14 microns. However, due to the cooling...

  7. Active Pixel HgCdTe Detectors With Built-in Dark Current Reduction for Near-Room Temperature Operation, Phase I (United States)

    National Aeronautics and Space Administration — High sensitivity HgCdTe infrared arrays operating at 77K can now be tailored in a wide range of wavelengths from 1 to14 um. However, the cooling requirements make...

  8. Very high resolution detection of gamma radiation at room-temperature using P-I-N detectors of CdZnTe and HgCdTe (United States)

    Hamilton, W. J.; Rhiger, D. R.; Sen, S.; Kalisher, M. H.; James, K.; Reid, C. P.; Gerrish, V.; Baccash, C. O.


    High-energy photon detectors have been constructed by engineering and fabricating p-i-n diode structures consisting of bulk CdZnTe and epitaxial HgCdTe. The p-i-n structure was obtained by liquid-phase epitaxial growth of p and n doped HgCdTe layers on 'intrinsic' CdZnTe material about 1mm thick and approximately 25mm square. Curve tracing shows I-V curves with diode characteristics having resistivity above 1011 Omega -cm and leakage current of less than 400 pA to about - 60V reverse bias on a typical test piece approximately 5 x 8 x 1 mm. Spectra of similar test pieces have been obtained at room temperature with various nuclear isotopic sources over the range of 22 keV to 662 keV which show exceptionally high energy resolution. Resolution as good as 1.82% FWHM was obtained for the 356 keV line of 133Ba with a P/V = 3.4. The performance of these detectors combined with contemporary infrared technology capable of fabricating 2D arrays of these II-VI materials opens up manifold exciting applications in astrophysics, medical, industrial, environmental, and defense spectroscopy and imaging.

  9. Measurements of Low Frequency Noise of Infrared Photo-Detectors with Transimpedance Detection System

    Directory of Open Access Journals (Sweden)

    Ciura Łukasz


    Full Text Available The paper presents the method and results of low-frequency noise measurements of modern mid-wavelength infrared photodetectors. A type-II InAs/GaSb superlattice based detector with nBn barrier architecture is compared with a high operating temperature (HOT heterojunction HgCdTe detector. All experiments were made in the range 1 Hz - 10 kHz at various temperatures by using a transimpedance detection system, which is examined in detail. The power spectral density of the nBn’s dark current noise includes Lorentzians with different time constants while the HgCdTe photodiode has more uniform 1/f - shaped spectra. For small bias, the low-frequency noise power spectra of both devices were found to scale linearly with bias voltage squared and were connected with the fluctuations of the leakage resistance. Leakage resistance noise defines the lower noise limit of a photodetector. Other dark current components give raise to the increase of low-frequency noise above this limit. For the same voltage biasing devices, the absolute noise power densities at 1 Hz in nBn are 1 to 2 orders of magnitude lower than in a MCT HgCdTe detector. In spite of this, low-frequency performance of the HgCdTe detector at ~ 230K is still better than that of InAs/GaSb superlattice nBn detector.

  10. Thermal noise in mid-infrared broadband upconversion detectors

    DEFF Research Database (Denmark)

    Barh, Ajanta; Tidemand-Lichtenberg, Peter; Pedersen, Christian


    Low noise detection with state-of-the-art mid-infrared (MIR) detectors (e.g., PbS, PbSe, InSb, HgCdTe) is a primary challenge owing to the intrinsic thermal background radiation of the low bandgap detector material itself. However, researchers have employed frequency upconversion based detectors...... of the noise-equivalent power of an UCD system. In this article, we rigorously analyze the optical power generated by frequency upconversion of the intrinsic black-body radiation in the nonlinear material itself due to the crystals residual emissivity, i.e. absorption. The thermal radiation is particularly...... prominent at the optical absorption edge of the nonlinear material even at room temperature. We consider a conventional periodically poled lithium niobate (PPLN) based MIR-UCD for the investigation. The UCD is designed to cover a broad spectral range, overlapping with the entire absorption edge of the PPLN...

  11. Recent progress in MBE grown HgCdTe materials and devices at UWA (United States)

    Gu, R.; Lei, W.; Antoszewski, J.; Madni, I.; Umana-Menbreno, G.; Faraone, L.


    HgCdTe has dominated the high performance end of the IR detector market for decades. At present, the fabrication costs of HgCdTe based advanced infrared devices is relatively high, due to the low yield associated with lattice matched CdZnTe substrates and a complicated cooling system. One approach to ease this problem is to use a cost effective alternative substrate, such as Si or GaAs. Recently, GaSb has emerged as a new alternative with better lattice matching. In addition, implementation of MBE-grown unipolar n-type/barrier/n-type detector structures in the HgCdTe material system has been recently proposed and studied intensively to enhance the detector operating temperature. The unipolar nBn photodetector structure can be used to substantially reduce dark current and noise without impeding photocurrent flow. In this paper, recent progress in MBE growth of HgCdTe infrared material at the University of Western Australia (UWA) is reported, including MBE growth of HgCdTe on GaSb alternative substrates and growth of HgCdTe nBn structures.

  12. Advanced far infrared detectors

    International Nuclear Information System (INIS)

    Haller, E.E.


    Recent advances in photoconductive and bolometric semiconductor detectors for wavelength 1 mm > λ > 50 μm are reviewed. Progress in detector performance in this photon energy range has been stimulated by new and stringent requirements for ground based, high altitude and space-borne telescopes for astronomical and astrophysical observations. The paper consists of chapters dealing with the various types of detectors: Be and Ga doped Ge photoconductors, stressed Ge:Ga devices and neutron transmutation doped Ge thermistors. Advances in the understanding of basic detector physics and the introduction of modern semiconductor device technology have led to predictable and reliable fabrication techniques. Integration of detectors into functional arrays has become feasible and is vigorously pursued by groups worldwide

  13. Optical study of HgCdTe infrared photodetectors using internal photoemission spectroscopy

    International Nuclear Information System (INIS)

    Lao, Yan-Feng; Unil Perera, A. G.; Wijewarnasuriya, Priyalal S.


    We report a study of internal photoemission spectroscopy (IPE) applied to a n-type Hg 1−x Cd x Te/Hg 1−y Cd y Te heterojunction. An exponential line-shape of the absorption tail in HgCdTe is identified by IPE fittings of the near-threshold quantum yield spectra. The reduction of quantum yield (at higher photon energy) below the fitting value is explained as a result of carrier-phonon scatterings. In addition, the obtained bias independence of the IPE threshold indicates a negligible electron barrier at the heterojunction interface

  14. InAs/GaSb type-II superlattice infrared detectors: Future prospect (United States)

    Rogalski, A.; Martyniuk, P.; Kopytko, M.


    Investigations of antimonide-based materials began at about the same time as HgCdTe ternary alloys—in the 1950s, and the apparent rapid success of their technology, especially low-dimensional solids, depends on the previous five decades of III-V materials and device research. However, the sophisticated physics associated with the antimonide-based bandgap engineering concept started at the beginning of 1990s gave a new impact and interest in development of infrared detector structures within academic and national laboratories. The development of InAs/GaSb type-II superlattices (T2SLs) results from two primary motivations: the perceived challenges of reproducibly fabricating high-operability HgCdTe focal plane arrays (FPAs) at reasonable cost and the theoretical predictions of lower Auger recombination for type T2SL detectors compared with HgCdTe. Second motivation—lower Auger recombination should be translated into a fundamental advantage for T2SL over HgCdTe in terms of lower dark current and/or higher operating temperature, provided other parameters such as Shockley-Read-Hall (SRH) lifetime are equal. InAs/GaSb T2SL photodetectors offer similar performance to HgCdTe at an equivalent cut-off wavelength, but with a sizeable penalty in operating temperature, due to the inherent difference in SRH lifetimes. It is predicted that since the future infrared (IR) systems will be based on the room temperature operation of depletion-current limited arrays with pixel densities that are fully consistent with background- and diffraction-limited performance due to the system optics, the material system with long SRH lifetime will be required. Since T2SLs are very much resisted in attempts to improve its SRH lifetime, currently the only material that meets this requirement is HgCdTe. Due to less ionic chemical bonding, III-V semiconductors are more robust than their II-VI counterparts. As a result, III-V-based FPAs excel in operability, spatial uniformity, temporal stability

  15. Analysis of the auger recombination rate in P+N-n-N-N HgCdTe detectors for HOT applications (United States)

    Schuster, J.; Tennant, W. E.; Bellotti, E.; Wijewarnasuriya, P. S.


    Infrared (IR) photon detectors must be cryogenically cooled to provide the highest possible performance, usually to temperatures at or below ~ 150K. Such low operating temperatures (Top) impose very stringent requirements on cryogenic coolers. As such, there is a constant push in the industry to engineer new detector architectures that operate at higher temperatures, so called higher operating temperature (HOT) detectors. The ultimate goal for HOT detectors is room temperature operation. While this is not currently possibly for photon detectors, significant increases in Top are nonetheless beneficial in terms of reduced size, weight, power and cost (SWAP-C). The most common HgCdTe IR detector architecture is the P+n heterostructure photodiode (where a capital letter indicates a wide band gap relative to the active layer or "AL"). A variant of this architecture, the P+N-n-N-N heterostructure photodiode, should have a near identical photo-response to the P+n heterostructure, but with significantly lower dark diffusion current. The P+N-n-N-N heterostructure utilizes a very low doped AL, surrounded on both sides by wide-gap layers. The low doping in the AL, allows the AL to be fully depleted, which drastically reduces the Auger recombination rate in that layer. Minimizing the Auger recombination rate reduces the intrinsic dark diffusion current, thereby increasing Top. Note when we use the term "recombination rate" for photodiodes, we are actually referring to the net generation and recombination of minority carriers (and corresponding dark currents) by the Auger process. For these benefits to be realized, these devices must be intrinsically limited and well passivated. The focus of this proceeding is on studying the fundamental physics of the intrinsic dark currents in ideal P+N-n-N-N heterostructures, namely Auger recombination. Due to the complexity of these devices, specifically the presence of multiple heterojunctions, numerical device modeling techniques must be

  16. Infrared detectors for Earth observation (United States)

    Barnes, K.; Davis, R. P.; Knowles, P.; Shorrocks, N.


    IASI (Infrared Atmospheric Sounding Interferometer), developed by CNES and launched since 2006 on the Metop satellites, is established as a major source of data for atmospheric science and weather prediction. The next generation - IASI NG - is a French national contribution to the Eumetsat Polar System Second Generation on board of the Metop second generation satellites and is under development by Airbus Defence and Space for CNES. The mission aim is to achieve twice the performance of the original IASI instrument in terms of sensitivity and spectral resolution. In turn, this places very demanding requirements on the infrared detectors for the new instrument. Selex ES in Southampton has been selected for the development of the infrared detector set for the IASI-NG instruments. The wide spectral range, 3.6 to 15.5 microns, is covered in four bands, each served by a dedicated detector design, with a common 4 x 4 array format of 1.3 mm square macropixels. Three of the bands up to 8.7 microns employ photovoltaic MCT (mercury cadmium telluride) technology and the very long wave band employs photoconductive MCT, in common with the approach taken between Airbus and Selex ES for the SEVIRI instrument on Second Generation Meteosat. For the photovoltaic detectors, the MCT crystal growth of heterojunction photodiodes is by the MOVPE technique (metal organic vapour phase epitaxy). Novel approaches have been taken to hardening the photovoltaic macropixels against localised crystal defects, and integrating transimpedance amplifiers for each macropixel into a full-custom silicon read out chip, which incorporates radiation hard design.

  17. Fast infrared detectors for beam diagnostics with synchrotron radiation

    International Nuclear Information System (INIS)

    Bocci, A.; Marcelli, A.; Pace, E.; Drago, A.; Piccinini, M.; Cestelli Guidi, M.; De Sio, A.; Sali, D.; Morini, P.; Piotrowski, J.


    Beam diagnostic is a fundamental constituent of any particle accelerators either dedicated to high-energy physics or to synchrotron radiation experiments. All storage rings emit radiations. Actually they are high brilliant sources of radiation: the synchrotron radiation emission covers from the infrared range to the X-ray domain with a pulsed structure depending on the temporal characteristics of the stored beam. The time structure of the emitted radiation is extremely useful as a tool to perform time-resolved experiments. However, this radiation can be also used for beam diagnostic to determine the beam stability and to measure the dimensions of the e - or e + beam. Because of the temporal structure of the synchrotron radiation to perform diagnostic, we need very fast detectors. Indeed, the detectors required for the diagnostics of the stored particle bunches at third generation synchrotron radiation sources and FEL need response times in the sub-ns and even ps range. To resolve the bunch length and detect bunch instabilities, X-ray and visible photon detectors may be used achieving response times of a few picoseconds. Recently, photon uncooled infrared devices optimized for the mid-IR range realized with HgCdTe semiconductors allowed to obtain sub-nanosecond response times. These devices can be used for fast detection of intense IRSR sources and for beam diagnostic. We present here preliminary experimental data of the pulsed synchrotron radiation emission of DAΦNE, the electron positron collider of the LNF laboratory of the INFN, performed with new uncooled IR detectors with a time resolution of a few hundreds of picoseconds

  18. Commentary: JWST near-infrared detector degradation— finding the problem, fixing the problem, and moving forward

    Directory of Open Access Journals (Sweden)

    Bernard J. Rauscher


    Full Text Available The James Webb Space Telescope (JWST is the successor to the Hubble Space Telescope. JWST will be an infrared-optimized telescope, with an approximately 6.5 m diameter primary mirror, that is located at the Sun-Earth L2 Lagrange point. Three of JWST’s four science instruments use Teledyne HgCdTe HAWAII-2RG (H2RG near infrared detector arrays. During 2010, the JWST Project noticed that a few of its 5 μm cutoff H2RG detectors were degrading during room temperature storage, and NASA chartered a “Detector Degradation Failure Review Board” (DD-FRB to investigate. The DD-FRB determined that the root cause was a design flaw that allowed indium to interdiffuse with the gold contacts and migrate into the HgCdTe detector layer. Fortunately, Teledyne already had an improved design that eliminated this degradation mechanism. During early 2012, the improved H2RG design was qualified for flight and JWST began making additional H2RGs. In this article, we present the two public DD-FRB “Executive Summaries” that: (1 determined the root cause of the detector degradation and (2 defined tests to determine whether the existing detectors are qualified for flight. We supplement these with a brief introduction to H2RG detector arrays, some recent measurements showing that the performance of the improved design meets JWST requirements, and a discussion of how the JWST Project is using cryogenic storage to retard the degradation rate of the existing flight spare H2RGs.

  19. Effect of surface fields on the dynamic resistance of planar HgCdTe mid-wavelength infrared photodiodes

    Energy Technology Data Exchange (ETDEWEB)

    He, Kai; Wang, Xi; Zhang, Peng; Chen, Yi-Yu [Key Laboratory of Infrared Imaging Materials and Detectors, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhou, Song-Min; Xie, Xiao-Hui; Lin, Chun, E-mail:; Ye, Zhen-Hua; Wang, Jian-Xin; Zhang, Qin-Yao, E-mail: [Key Laboratory of Infrared Imaging Materials and Detectors, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Li, Yang [Graduate School of Information Science and Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)


    This work investigates the effect of surface fields on the dynamic resistance of a planar HgCdTe mid-wavelength infrared photodiode from both theoretical and experimental aspects, considering a gated n-on-p diode with the surface potential of its p-region modulated. Theoretical models of the surface leakage current are developed, where the surface tunnelling current in the case of accumulation is expressed by modifying the formulation of bulk tunnelling currents, and the surface channel current for strong inversion is simulated with a transmission line method. Experimental data from the fabricated devices show a flat-band voltage of V{sub FB}=−5.7 V by capacitance-voltage measurement, and then the physical parameters for bulk properties are determined from the resistance-voltage characteristics of the diode working at a flat-band gate voltage. With proper values of the modeling parameters such as surface trap density and channel electron mobility, the theoretical R{sub 0}A product and corresponding dark current calculated from the proposed model as functions of the gate voltage V{sub g} demonstrate good consistency with the measured values. The R{sub 0}A product remarkably degenerates when V{sub g} is far below or above V{sub FB} because of the surface tunnelling current or channel current, respectively; and it attains the maximum value of 5.7×10{sup 7} Ω · cm{sup 2} around the transition between surface depletion and weak inversion when V{sub g}≈−4 V, which might result from reduced generation-recombination current.

  20. Germanium blocked impurity band far infrared detectors

    International Nuclear Information System (INIS)

    Rossington, C.S.


    The infrared portion of the electromagnetic spectrum has been of interest to scientist since the eighteenth century when Sir William Herschel discovered the infrared as he measured temperatures in the sun's spectrum and found that there was energy beyond the red. In the late nineteenth century, Thomas Edison established himself as the first infrared astronomer to look beyond the solar system when he observed the star Arcturus in the infrared. Significant advances in infrared technology and physics, long since Edison's time, have resulted in many scientific developments, such as the Infrared Astronomy Satellite (IRAS) which was launched in 1983, semiconductor infrared detectors for materials characterization, military equipment such as night-vision goggles and infrared surveillance equipment. It is now planned that cooled semiconductor infrared detectors will play a major role in the ''Star Wars'' nuclear defense scheme proposed by the Reagan administration

  1. Megapixel mercury cadmium telluride focal plane arrays for infrared imaging out to 12 microns, Phase I (United States)

    National Aeronautics and Space Administration — We propose the fabrication of large format, long wave infrared (LWIR) mercury cadmium telluride (HgCdTe or MCT) detector arrays where the cutoff wavelength is...

  2. Laboratory Measurement of the Brighter-fatter Effect in an H2RG Infrared Detector (United States)

    Plazas, A. A.; Shapiro, C.; Smith, R.; Huff, E.; Rhodes, J.


    The “brighter-fatter” (BF) effect is a phenomenon—originally discovered in charge coupled devices—in which the size of the detector point-spread function (PSF) increases with brightness. We present, for the first time, laboratory measurements demonstrating the existence of the effect in a Hawaii-2RG HgCdTe near-infrared (NIR) detector. We use JPL’s Precision Projector Laboratory, a facility for emulating astronomical observations with UV/VIS/NIR detectors, to project about 17,000 point sources onto the detector to stimulate the effect. After calibrating the detector for nonlinearity with flat-fields, we find evidence that charge is nonlinearly shifted from bright pixels to neighboring pixels during exposures of point sources, consistent with the existence of a BF-type effect. NASAs Wide Field Infrared Survey Telescope (WFIRST) will use similar detectors to measure weak gravitational lensing from the shapes of hundreds of million of galaxies in the NIR. The WFIRST PSF size must be calibrated to ≈0.1% to avoid biased inferences of dark matter and dark energy parameters; therefore further study and calibration of the BF effect in realistic images will be crucial.

  3. IR detectors for the Infrared Atmospheric Sounding Interferometer (IASI) instrument payload for the METOP-1 ESA polar platform (United States)

    Royer, Michel; Lorans, Dominique; Bischoff, Isabelle; Giotta, Dominique; Wolny, Michel


    IASI is an Infrared Atmospheric Sounding Interferometer devoted to the operational meteorology and to atmospheric studies and is to be installed on board the second ESA Polar Platform called METOP-1, planned to be launched in the year 2000. The main purpose of this high performance instrument is to record temperature and humidity profiles. The required lifetime is 4 years. This paper presents the characteristics of the LW IR detection arrays for the IASI spectrometer which consist of HgCdTe de- tectors. SAT has to develop the Engineering Model, Qualification Model and Fight Models of detectors, each having 4 pixels and AR-coated microlenses in a dedicated space housing equipped with a flexible line and a connector. An array is composed of HgCdTe photoconductive detectors. For this long wavelength the array is sensitive from 8.26 micrometers to 15.5 micrometers . The detectors, with sensitive areas of 900 x 900 micrometers 2, are 100 K operating with passive cooling. High quality HgCdTe material is a key feature for the manufacturing of high performance photoconductive detectors. Therefore epitaxial HgCdTe layers are used in this project. These epilayers are grown at CEA/LETI on lattice matched CdZnTe substrates, by Te-rich liquid phase epitaxy, based on a slider technique. The Cd content in the layer is carefully adjusted to meet the required cut off wavelength on the devices. After growth of the epilayers, the samples are annealed under Hg pressure in order to convert them into N type mate- rials. The electrical transport properties of the liquid phase epitaxied wafers are, at 100 K, mobility (mu) over 150,000 cm2/V.s and electrical concentration N of 1.5 1015 cm-3, the residual doping level being 1014 cm-3 at low temperature. On these materials the feasibility study of long wavelength HgCdTe photoconductors has been achieved with the following results: the responsivity is 330 V/W. The bias voltage is Vp=300 mV for a 4 mW limitation of power for each element. The

  4. HgCdTe APDS for space applications (United States)

    Rothman, Johan; de Broniol, Eric; Foubert, Kevin; Mollard, Laurent; Péré-Laperne, Nicolas; Salvetti, Frederic; Kerlain, Alexandre; Reibel, Yann


    HgCdTe avalanche photodiode focal plane arrays (FPAs) and single element detectors have been developed for a large scope of photon starved applications. The present communication present the characteristics of our most recent detector developments that opens the horizon for low infrared (IR) photon number detection with high information conservation for imaging, atmospheric lidar and free space telecommunications. In particular, we report on the performance of TEC cooled large area detectors with sensitive diameters ranging from 30- 200 μm, characterised by detector gains of 2- 20 V/μW and noise equivalent input power of 0.1-1 nW for bandwidths ranging from 20 to 400 MHz.

  5. Two-color infrared detector (United States)

    Klem, John F; Kim, Jin K


    A two-color detector includes a first absorber layer. The first absorber layer exhibits a first valence band energy characterized by a first valence band energy function. A barrier layer adjoins the first absorber layer at a first interface. The barrier layer exhibits a second valence band energy characterized by a second valence band energy function. The barrier layer also adjoins a second absorber layer at a second interface. The second absorber layer exhibits a third valence band energy characterized by a third valence band energy function. The first and second valence band energy functions are substantially functionally or physically continuous at the first interface and the second and third valence band energy functions are substantially functionally or physically continuous at the second interface.

  6. The Effect of Metal-Semiconductor Contact on the Transient Photovoltaic Characteristic of HgCdTe PV Detector

    Directory of Open Access Journals (Sweden)

    Haoyang Cui


    Full Text Available The transient photovoltaic (PV characteristic of HgCdTe PV array is studied using an ultrafast laser. The photoresponse shows an apparent negative valley first, then it evolves into a positive peak. By employing a combined theoretical model of pn junction and Schottky potential, this photo-response polarity changing curves can be interpreted well. An obvious decreasing of ratio of negative valley to positive peak can be realized by limiting the illumination area of the array electrode. This shows that the photoelectric effect of Schottky barrier at metal-semiconductor (M/S interface is suppressed, which will verify the correctness of the model. The characteristic parameters of transient photo-response induced from p-n junction and Schottky potential are extracted by fitting the response curve utilizing this model. It shows that the negative PV response induced by the Schottky barrier decreases the positive photovoltage generated by the pn junction.

  7. Radiation effects in IRAS extrinsic infrared detectors (United States)

    Varnell, L.; Langford, D. E.


    During the calibration and testing of the Infrared Astronomy Satellite (IRAS) focal plane, it was observed that the extrinsic photoconductor detectors were affected by gamma radiation at dose levels of the order of one rad. Since the flight environment will subject the focal plane to dose levels of this order from protons in single pass through the South Atlantic Anomaly, an extensive program of radiation tests was carried out to measure the radiation effects and to devise a method to counteract these effects. The effects observed after irradiation are increased responsivity, noise, and rate of spiking of the detectors after gamma-ray doses of less than 0.1 rad. The detectors can be returned almost to pre-irradiation performance by increasing the detector bias to breakdown and allowing a large current to flow for several minutes. No adverse effects on the detectors have been observed from this bias boost, and this technique will be used for IRAS with frequent calibration to ensure the accuracy of observations made with the instrument.

  8. InAs/GaSb type-II superlattice infrared detectors: three decades of development (United States)

    Rogalski, A.; Kopytko, M.; Martyniuk, P.


    Recently, there has been considerable progress towards III-V antimonide-based low dimensional solids development and device design innovations. From a physics point of view, the type-II InAs/GaSb superlattice is an extremely attractive proposition. Their development results from two primary motivations: the perceived challenges of reproducibly fabricating high-operability HgCdTe FPAs at reasonable cost and theoretical predictions of lower Auger recombination for type-II superlattice (T2SL) detectors compared to HgCdTe. Lower Auger recombination should be translated into a fundamental advantage for T2SL over HgCdTe in terms of lower dark current and/or higher operating temperature, provided other parameters such as Shockley-Read-Hall lifetime are equal. Based on these promising results it is obvious now that the InAs/GaSb superlattice technology is competing with HgCdTe third generation detector technology with the potential advantage of standard III-V technology to be more competitive in costs and as a consequence series production pricing. Comments to the statement whether the superlattice IR photodetectors can outperform the "bulk" narrow gap HgCdTe detectors is one of the most important questions for the future of IR photodetectors presented by Rogalski at the April 2006 SPIE meeting in Orlando, Florida, are more credible today and are presented in this paper. It concerns the trade-offs between two most competing IR material technologies: InAs/GaSb type-II superlattices and HgCdTe ternary alloy system.

  9. Infrared detectors and focal plane arrays II; Proceedings of the Meeting, Orlando, FL, Apr. 23, 24, 1992 (United States)

    Dereniak, Eustace L.; Sampson, Robert E.

    The present conference discusses Schottky-barrier IR image sensors, SWIR and MWIR Schottky-barrier imagers, a 640 x 640 PtSi, models of nonlinearities in focal plane arrays, retinal function relative to IRT focal plane arrays, a solid-state pyroelectric imager, and electrolyte electroreflectance spectroscopies for the ion-implanted HgCdTe with thermal annealing. Also discussed are HgCdTe hybrid focal plane arrays for thermoelectrically cooled applications, a novel IR detector plasma-edge detector, and IR detector circuits using monolithic CMOS amps with InSb detectors. (No individual items are abstracted in this volume)

  10. Single-Band and Dual-Band Infrared Detectors (United States)

    Ting, David Z. (Inventor); Gunapala, Sarath D. (Inventor); Soibel, Alexander (Inventor); Nguyen, Jean (Inventor); Khoshakhlagh, Arezou (Inventor)


    Bias-switchable dual-band infrared detectors and methods of manufacturing such detectors are provided. The infrared detectors are based on a back-to-back heterojunction diode design, where the detector structure consists of, sequentially, a top contact layer, a unipolar hole barrier layer, an absorber layer, a unipolar electron barrier, a second absorber, a second unipolar hole barrier, and a bottom contact layer. In addition, by substantially reducing the width of one of the absorber layers, a single-band infrared detector can also be formed.

  11. Gerard Kuiper and the Infrared Detector (United States)

    Sears, Derek


    The life and contributions of Gerard Kuiper have been documented by Dale Cruikshank in his National Academy of Sciences biography. I will argue that particularly important in this eventful life was Kuiper's war time experiences. Kuiper's wartime role evolved as the war unfolded, but towards the end he was charged by the US military with reporting German progress with war-related technologies and the activities of scientists under Nazi control. He interviewed a great many scientists, including his own PhD mentor (Ejnar Hertzsprung), and when Kuiper was the only person available, he interviewed concentration-camp victims. He carried briefing sheets that identified the technologies being sought by the allies and the major fraction of these involved infrared equipment. He sent back to the USA boxes of documents, and large amounts of equipment, and he stressed to the military his interest in these for his own research. It seems very likely that in this way an effective PbS infrared detector, so critical to Kuiper's career and the future of planetary science, came to the USA and to Robert Cashman's laboratory at Northwestern University. As the war was winding down, Cashman and Kuiper worked together to develop a practical infrared spectrometer for astronomical use. Within months, Kuiper discovered the C02 atmospheres on Mars and Venus.

  12. Innovative mid-infrared detector concepts (United States)

    Höfling, Sven; Pfenning, Andreas; Weih, Robert; Ratajczak, Albert; Hartmann, Fabian; Knebl, Georg; Kamp, Martin; Worschech, Lukas


    Gas sensing is a key technology with applications in various industrial, medical and environmental areas. Optical detection mechanisms allow for a highly selective, contactless and fast detection. For this purpose, rotational-vibrational absorption bands within the mid infrared (MIR) spectral region are exploited and probed with appropriate light sources. During the past years, the development of novel laser concepts such as interband cascade lasers (ICLs) and quantum cascade lasers (QCLs) has driven a continuous optimization of MIR laser sources. On the other hand side, there has been relatively little progress on detectors in this wavelength range. Here, we study two novel and promising GaSb-based detector concepts: Interband cascade detectors (ICD) and resonant tunneling diode (RTD) photodetectors. ICDs are a promising approach towards highly sensitive room temperature detection of MIR radiation. They make use of the cascading scheme that is enabled by the broken gap alignment of the two binaries GaSb and InAs. The interband transition in GaSb/InAs-superlattices (SL) allows for normal incidence detection. The cut-off wavelength, which determines the low energy detection limit, can be engineered via the SL period. RTD photodetectors act as low noise and high speed amplifiers of small optically generated electrical signals. In contrast to avalanche photodiodes, where the gain originates from multiplication due to impact ionization, in RTD photodetectors a large tunneling current is modulated via Coulomb interaction by the presence of photogenerated minority charge carriers. For both detector concepts, first devices operational at room temperature have been realized.

  13. Airborne measurements of CO2 column concentrations made with a pulsed IPDA lidar using a multiple-wavelength-locked laser and HgCdTe APD detector (United States)

    Abshire, James B.; Ramanathan, Anand K.; Riris, Haris; Allan, Graham R.; Sun, Xiaoli; Hasselbrack, William E.; Mao, Jianping; Wu, Stewart; Chen, Jeffrey; Numata, Kenji; Kawa, Stephan R.; Yang, Mei Ying Melissa; DiGangi, Joshua


    Here we report on measurements made with an improved CO2 Sounder lidar during the ASCENDS 2014 and 2016 airborne campaigns. The changes made to the 2011 version of the lidar included incorporating a rapidly wavelength-tunable, step-locked seed laser in the transmitter, using a much more sensitive HgCdTe APD detector and using an analog digitizer with faster readout time in the receiver. We also improved the lidar's calibration approach and the XCO2 retrieval algorithm. The 2014 and 2016 flights were made over several types of topographic surfaces from 3 to 12 km aircraft altitudes in the continental US. The results are compared to the XCO2 values computed from an airborne in situ sensor during spiral-down maneuvers. The 2014 results show significantly better performance and include measurement of horizontal gradients in XCO2 made over the Midwestern US that agree with chemistry transport models. The results from the 2016 airborne lidar retrievals show precisions of ˜ 0.7 parts per million (ppm) with 1 s averaging over desert surfaces, which is an improvement of about 8 times compared to similar measurements made in 2011. Measurements in 2016 were also made over fresh snow surfaces that have lower surface reflectance at the laser wavelengths. The results from both campaigns showed that the mean values of XCO2 retrieved from the lidar consistently agreed with those based on the in situ sensor to within 1 ppm. The improved precision and accuracy demonstrated in the 2014 and 2016 flights should benefit future airborne science campaigns and advance the technique's readiness for a space-based instrument.

  14. On the sensitivity of heterodyne detectors in far infrared astronomy

    International Nuclear Information System (INIS)

    Bueren, H.G. van


    The signal-to-noise ratio of astronomical heterodyne detection infrared spectrographs is considered, taking into account background, linewidth and seeing effects. A comparison with incoherent detector systems is presented. (author)

  15. Design of the flame detector based on pyroelectric infrared sensor (United States)

    Liu, Yang; Yu, Benhua; Dong, Lei; Li, Kai


    As a fire detection device, flame detector has the advantages of short reaction time and long distance. Based on pyroelectric infrared sensor working principle, the passive pyroelectric infrared alarm system is designed, which is mainly used for safety of tunnel to detect whether fire occurred or not. Modelling and Simulation of the pyroelectric Detector Using Labview. An attempt was made to obtain a simple test platform of a pyroelectric detector which would make an excellent basis for the analysis of its dynamic behaviour. After many experiments, This system has sensitive response, high anti-interference ability and safe and reliable performance.

  16. Infra-red signature neutron detector (United States)

    Bell, Zane William [Oak Ridge, TN; Boatner, Lynn Allen [Oak Ridge, TN


    A method of detecting an activator, the method including impinging with an activator a receptor material that includes a photoluminescent material that generates infrared radiation and generation a by-product of a nuclear reaction due to the activator impinging the receptor material. The method further includes generating light from the by-product via the Cherenkov effect, wherein the light activates the photoluminescent material so as to generate the infrared radiation. Identifying a characteristic of the activator based on the infrared radiation.

  17. Effect of Low Temperature on a 4 W/60 K Pulse-Tube Cryocooler for Cooling HgCdTe Detector (United States)

    Zhang, Ankuo; Liu, Shaoshuai; Wu, Yinong


    Temperature is an extremely important parameter for the material of the space-borne infrared detector. To cool an HgCdTe-infrared detector, a Stirling-type pulse-tube cryocooler (PTC) has been developed based on a great deal of numerical simulations, which are performed to investigate the thermodynamic behaviors of the PTC. The effects of different low temperatures are presented to analyze different energy flows, losses, phase shifts, and impedance matching of the PTC at a temperature range of 40-120 K, where woven wire screens are used. Finally, a high-efficiency coaxial PTC has been designed, built, and tested, operating around 60 K after a number of theoretical and experimental studies. The PTC can offer a no-load refrigeration temperature of 40 K with an input electric power of 150 W, and a cooling power of 4 W at 60 K is obtained with Carnot efficiency of 12%. In addition, a comparative study of simulation and experiment has been carried out, and some studies on reject temperatures have been presented for a thorough understanding of the PTC system.

  18. Josephson effect far-infrared detector

    International Nuclear Information System (INIS)

    Shapiro, S.


    Four Josephson effect schemes for detection of far-infrared radiation are reviewed: Video broad-band detection, regenerative detection, conventional mixing for monochromatic signals, and self-mixing or frequency conversion. (U.S.)

  19. Development of Buffer Layer Technologies for LWIR and VLWIR HgCdTe Integration on Si

    National Research Council Canada - National Science Library

    Golding, Terry D


    This program proposed to develop manufacturable, cost-effective buffer layer technologies that would allow either hybrid or monolithic integration of LWIR and VLWIR HgCdTe infrared focal plane arrays...

  20. Effects of ionizing radiation on cryogenic infrared detectors (United States)

    Moseley, S. H.; Silverberg, R. F.; Lakew, B.


    The Diffuse Infrared Background Experiment (DIRBE) is one of three experiments to be carried aboard the Cosmic Background Explorer (COBE) satellite scheduled to be launched by NASA on a Delta rocket in 1989. The DIRBE is a cryogenic absolute photometer operating in a liquid helium dewar at 1.5 K. Photometric stability is a principal requirement for achieving the scientific objectives of this experiment. The Infrared Astronomy Satellite (IRAS), launched in 1983, which used detectors similar to those in DIRBE, revealed substantial changes in detector responsivity following exposure to ionizing radiation encountered on passage through the South Atlantic Anomaly (SAA). Since the COBE will use the same 900 Km sun-synchronous orbit as IRAS, ionizing radiation-induced performance changes in the detectors were a major concern. Here, ionizing radiation tests carried out on all the DIRBE photodetectors are reported. Responsivity changes following exposure to gamma rays, protons, and alpha particle are discussed. The detector performance was monitored following a simulated entire mission life dose. In addition, the response of the detectors to individual particle interactions was measured. The InSb photovoltaic detectors and the Blocked Impurity Band (BIB) detectors revealed no significant change in responsivity following radiation exposure. The Ge:Ga detectors show large effects which were greatly reduced by proper thermal annealing.

  1. Ultra-thin infrared metamaterial detector for multicolor imaging applications. (United States)

    Montoya, John A; Tian, Zhao-Bing; Krishna, Sanjay; Padilla, Willie J


    The next generation of infrared imaging systems requires control of fundamental electromagnetic processes - absorption, polarization, spectral bandwidth - at the pixel level to acquire desirable information about the environment with low system latency. Metamaterial absorbers have sparked interest in the infrared imaging community for their ability to enhance absorption of incoming radiation with color, polarization and/or phase information. However, most metamaterial-based sensors fail to focus incoming radiation into the active region of a ultra-thin detecting element, thus achieving poor detection metrics. Here our multifunctional metamaterial absorber is directly integrated with a novel mid-wave infrared (MWIR) and long-wave infrared (LWIR) detector with an ultra-thin (~λ/15) InAs/GaSb Type-II superlattice (T2SL) interband cascade detector. The deep sub-wavelength metamaterial detector architecture proposed and demonstrated here, thus significantly improves the detection quantum efficiency (QE) and absorption of incoming radiation in a regime typically dominated by Fabry-Perot etalons. Our work evinces the ability of multifunctional metamaterials to realize efficient wavelength selective detection across the infrared spectrum for enhanced multispectral infrared imaging applications.

  2. Pyroelectric Materials for Uncooled Infrared Detectors: Processing, Properties, and Applications (United States)

    Aggarwal, M. D.; Batra, A. K.; Guggilla, P.; Edwards, M. E.; Penn, B. G.; Currie, J. R., Jr.


    Uncooled pyroelectric detectors find applications in diverse and wide areas such as industrial production; automotive; aerospace applications for satellite-borne ozone sensors assembled with an infrared spectrometer; health care; space exploration; imaging systems for ships, cars, and aircraft; and military and security surveillance systems. These detectors are the prime candidates for NASA s thermal infrared detector requirements. In this Technical Memorandum, the physical phenomena underlying the operation and advantages of pyroelectric infrared detectors is introduced. A list and applications of important ferroelectrics is given, which is a subclass of pyroelectrics. The basic concepts of processing of important pyroelectrics in various forms are described: single crystal growth, ceramic processing, polymer-composites preparation, and thin- and thick-film fabrications. The present status of materials and their characteristics and detectors figures-of-merit are presented in detail. In the end, the unique techniques demonstrated for improving/enhancing the performance of pyroelectric detectors are illustrated. Emphasis is placed on recent advances and emerging technologies such as thin-film array devices and novel single crystal sensors.

  3. Emerging technologies for high performance infrared detectors


    Tan Chee Leong; Mohseni Hooman


    Infrared photodetectors (IRPDs) have become important devices in various applications such as night vision, military missile tracking, medical imaging, industry defect imaging, environmental sensing, and exoplanet exploration. Mature semiconductor technologies such as mercury cadmium telluride and III–V material-based photodetectors have been dominating the industry. However, in the last few decades, significant funding and research has been focused to improve the performance of IRPDs such as...

  4. Mid-Infrared Tunable Resonant Cavity Enhanced Detectors

    Directory of Open Access Journals (Sweden)

    Hans Zogg


    Full Text Available Mid-infrared detectors that are sensitive only in a tunable narrow spectral band are presented. They are based on the Resonant Cavity Enhanced Detector (RCED principle and employing a thin active region using IV-VI narrow gap semiconductor layers. A Fabry-Pérot cavity is formed by two mirrors. The active layer is grown onto one mirror, while the second mirror can be displaced. This changes the cavity length thus shifting the resonances where the detector is sensitive. Using electrostatically actuated MEMS micromirrors, a very compact tunable detector system has been fabricated. Mirror movements of more than 3 μm at 30V are obtained. With these mirrors, detectors with a wavelength tuning range of about 0.7 μm have been realized. Single detectors can be used in mid-infrared micro spectrometers, while a detector arrangement in an array makes it possible to realize Adaptive Focal Plane Arrays (AFPA.

  5. Challenges of small-pixel infrared detectors: a review. (United States)

    Rogalski, A; Martyniuk, P; Kopytko, M


    In the last two decades, several new concepts for improving the performance of infrared detectors have been proposed. These new concepts particularly address the drive towards the so-called high operating temperature focal plane arrays (FPAs), aiming to increase detector operating temperatures, and as a consequence reduce the cost of infrared systems. In imaging systems with the above megapixel formats, pixel dimension plays a crucial role in determining critical system attributes such as system size, weight and power consumption (SWaP). The advent of smaller pixels has also resulted in the superior spatial and temperature resolution of these systems. Optimum pixel dimensions are limited by diffraction effects from the aperture, and are in turn wavelength-dependent. In this paper, the key challenges in realizing optimum pixel dimensions in FPA design including dark current, pixel hybridization, pixel delineation, and unit cell readout capacity are outlined to achieve a sufficiently adequate modulation transfer function for the ultra-small pitches involved. Both photon and thermal detectors have been considered. Concerning infrared photon detectors, the trade-offs between two types of competing technology-HgCdTe material systems and III-V materials (mainly barrier detectors)-have been investigated.

  6. Improved mid infrared detector for high spectral or spatial resolution and synchrotron radiation use

    Energy Technology Data Exchange (ETDEWEB)

    Faye, Mbaye; Bordessoule, Michel; Kanouté, Brahim; Brubach, Jean-Blaise; Roy, Pascale [Synchrotron SOLEIL, L’Orme des Merisiers, F-91192 Gif-sur-Yvette (France); Manceron, Laurent [Synchrotron SOLEIL, L’Orme des Merisiers, F-91192 Gif-sur-Yvette (France); Laboratoire MONARIS, CNRS-Université Pierre et Marie Curie, UMR 8233, 4 Place Jussieu, F-75252 Paris Cedex (France)


    When using bright, small effective size sources, such as synchrotron radiation light beam, for broadband spectroscopy at spectral or spatial high resolution for mid-IR FTIR measurements, a marked detectivity improvement can be achieved by setting up a device matching the detector optical étendue to that of the source. Further improvement can be achieved by reducing the background unmodulated flux and other intrinsic noise sources using a lower temperature cryogen, such as liquid helium. By the combined use of cooled apertures, cold reimaging optics, filters and adapted detector polarization, and preamplification electronics, the sensitivity of a HgCdTe photoconductive IR detector can be improved by a significant factor with respect to standard commercial devices (more than one order of magnitude on average over 6–20 μm region) and the usable spectral range extended to longer wavelengths. The performances of such an optimized detector developed on the AILES Beamline at SOLEIL are presented here.

  7. Infrared detectors, focal plane arrays, and imaging sensors; Proceedings of the Meeting, Orlando, FL, Mar. 30, 31, 1989 (United States)

    Dereniak, Eustace L.; Sampson, Robert T.


    The present conference on advancements in IR detectors, Schottky-barrier focal plane arrays, CCD image analysis, and HgCdTe materials gives attention to a 256 x 256 PtSi array for IR astronomy, proposals for a second-generation meteosat's advanced optical payload, cryogenic bipolar technology for on-focal-plane signal processing, a parallel cellular processing system for fast generation of perspective plots, and ultrahigh-speed CCD image sensors for scanning applications. Also discussed are MBE GaAs rib waveguide experiments at 10.6 microns, an interferometric thermal detector, the development status of superconducting IR detector research, the absorption coefficients of n-type Hg(1-x)Cd(x)Te samples, and the influence of the surface channel on crosstalk in HgCdTe photovoltaic arrays.

  8. Enhancing the Responsivity of Uncooled Infrared Detectors Using Plasmonics for High-Performance Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    Amr Shebl Ahmed


    Full Text Available A lead zirconate titanate (PZT;Pb(Zr0.52Ti0.48O3 layer embedded infrared (IR detector decorated with wavelength-selective plasmonic crystals has been investigated for high-performance non-dispersive infrared (NDIR spectroscopy. A plasmonic IR detector with an enhanced IR absorption band has been designed based on numerical simulations, fabricated by conventional microfabrication techniques, and characterized with a broadly tunable quantum cascade laser. The enhanced responsivity of the plasmonic IR detector at specific wavelength band has improved the performance of NDIR spectroscopy and pushed the limit of detection (LOD by an order of magnitude. In this paper, a 13-fold enhancement in the LOD of a methane gas sensing using NDIR spectroscopy is demonstrated with the plasmonic IR detector.

  9. Emerging technologies for high performance infrared detectors (United States)

    Tan, Chee Leong; Mohseni, Hooman


    Infrared photodetectors (IRPDs) have become important devices in various applications such as night vision, military missile tracking, medical imaging, industry defect imaging, environmental sensing, and exoplanet exploration. Mature semiconductor technologies such as mercury cadmium telluride and III-V material-based photodetectors have been dominating the industry. However, in the last few decades, significant funding and research has been focused to improve the performance of IRPDs such as lowering the fabrication cost, simplifying the fabrication processes, increasing the production yield, and increasing the operating temperature by making use of advances in nanofabrication and nanotechnology. We will first review the nanomaterial with suitable electronic and mechanical properties, such as two-dimensional material, graphene, transition metal dichalcogenides, and metal oxides. We compare these with more traditional low-dimensional material such as quantum well, quantum dot, quantum dot in well, semiconductor superlattice, nanowires, nanotube, and colloid quantum dot. We will also review the nanostructures used for enhanced light-matter interaction to boost the IRPD sensitivity. These include nanostructured antireflection coatings, optical antennas, plasmonic, and metamaterials.

  10. Emerging technologies for high performance infrared detectors

    Directory of Open Access Journals (Sweden)

    Tan Chee Leong


    Full Text Available Infrared photodetectors (IRPDs have become important devices in various applications such as night vision, military missile tracking, medical imaging, industry defect imaging, environmental sensing, and exoplanet exploration. Mature semiconductor technologies such as mercury cadmium telluride and III–V material-based photodetectors have been dominating the industry. However, in the last few decades, significant funding and research has been focused to improve the performance of IRPDs such as lowering the fabrication cost, simplifying the fabrication processes, increasing the production yield, and increasing the operating temperature by making use of advances in nanofabrication and nanotechnology. We will first review the nanomaterial with suitable electronic and mechanical properties, such as two-dimensional material, graphene, transition metal dichalcogenides, and metal oxides. We compare these with more traditional low-dimensional material such as quantum well, quantum dot, quantum dot in well, semiconductor superlattice, nanowires, nanotube, and colloid quantum dot. We will also review the nanostructures used for enhanced light-matter interaction to boost the IRPD sensitivity. These include nanostructured antireflection coatings, optical antennas, plasmonic, and metamaterials.

  11. Insight on quantum dot infrared photodetectors

    International Nuclear Information System (INIS)

    Rogalski, A


    The paper presents possible future developments of quantum dot infrared photodetectors (QDIPs). At the beginning the fundamental properties of QDIPs are summarized. Next, investigations of the performance of QDIPs, as compared to other types of infrared photodetectors, are presented. Theoretical predictions indicate that only type II superlattice photodiodes and QDIPs are expected to compete with HgCdTe photodiodes. QDIPs theoretically have several advantages compared with QWIPs including the normal incidence response, lower dark current, higher operating temperature, higher responsivity and detectivity. The operating temperature for HgCdTe detectors is higher than for other types of photon detectors. Comparison of QDIP performance with HgCdTe detectors gives evidence that the QDIP is suitable for high operation temperature. It can be expected that an improvement in technology and design of QDIP detectors will make it possible to achieve both high sensitivity and fast response useful for practical application at room temperature focal plane arrays. However, so far the QDIP devices have not fully demonstrated their potential advantages.

  12. Performance overview of the Euclid infrared focal plane detector subsystems (United States)

    Waczynski, A.; Barbier, R.; Cagiano, S.; Chen, J.; Cheung, S.; Cho, H.; Cillis, A.; Clémens, J.-C.; Dawson, O.; Delo, G.; Farris, M.; Feizi, A.; Foltz, R.; Hickey, M.; Holmes, W.; Hwang, T.; Israelsson, U.; Jhabvala, M.; Kahle, D.; Kan, Em.; Kan, Er.; Loose, M.; Lotkin, G.; Miko, L.; Nguyen, L.; Piquette, E.; Powers, T.; Pravdo, S.; Runkle, A.; Seiffert, M.; Strada, P.; Tucker, C.; Turck, K.; Wang, F.; Weber, C.; Williams, J.


    In support of the European space agency (ESA) Euclid mission, NASA is responsible for the evaluation of the H2RG mercury cadmium telluride (MCT) detectors and electronics assemblies fabricated by Teledyne imaging systems. The detector evaluation is performed in the detector characterization laboratory (DCL) at the NASA Goddard space flight center (GSFC) in close collaboration with engineers and scientists from the jet propulsion laboratory (JPL) and the Euclid project. The Euclid near infrared spectrometer and imaging photometer (NISP) will perform large area optical and spectroscopic sky surveys in the 0.9-2.02 μm infrared (IR) region. The NISP instrument will contain sixteen detector arrays each coupled to a Teledyne SIDECAR application specific integrated circuit (ASIC). The focal plane will operate at 100K and the SIDECAR ASIC will be in close proximity operating at a slightly higher temperature of 137K. This paper will describe the test configuration, performance tests and results of the latest engineering run, also known as pilot run 3 (PR3), consisting of four H2RG detectors operating simultaneously. Performance data will be presented on; noise, spectral quantum efficiency, dark current, persistence, pixel yield, pixel to pixel uniformity, linearity, inter pixel crosstalk, full well and dynamic range, power dissipation, thermal response and unit cell input sensitivity.

  13. Infrared detectors and test technology of cryogenic camera (United States)

    Yang, Xiaole; Liu, Xingxin; Xing, Mailing; Ling, Long


    Cryogenic camera which is widely used in deep space detection cools down optical system and support structure by cryogenic refrigeration technology, thereby improving the sensitivity. Discussing the characteristics and design points of infrared detector combined with camera's characteristics. At the same time, cryogenic background test systems of chip and detector assembly are established. Chip test system is based on variable cryogenic and multilayer Dewar, and assembly test system is based on target and background simulator in the thermal vacuum environment. The core of test is to establish cryogenic background. Non-uniformity, ratio of dead pixels and noise of test result are given finally. The establishment of test system supports for the design and calculation of infrared systems.

  14. Infrared Illuminated CdZnTe detectors with improved performance

    International Nuclear Information System (INIS)

    Ivanov, V.; Loutchanski, A.; Dorogov, P.; Khinoverov, S.


    It was found that IR illumination of a properly chosen wavelength and intensity can significantly improve spectrometric characteristics of CdZnTe quasi-hemispherical detectors [1]. Improving of the spectrometric characteristics is due to improvement of uniformity of charge collection by the detector volume. For operation at room temperature the optimal wavelength of IR illumination is about 940 nm, but for operation at lower temperature of -20 deg. C the optimal wavelengths of IR illumination is about 1050 nm. Infrared illumination can be performed using conventional low-power IR LEDs. Application of SMD LEDs allows produce miniature detection probes with IR illuminated CdZnTe detectors. We have fabricated and tested a variety of detection probes with CdZnTe quasi-hemispherical detectors from the smallest with volumes of 1-5 mm 3 to larger with volumes of 1.5 cm 3 and 4.0 cm 3 . The use of IR illumination significantly improves spectrometric characteristics of the probes operating at room temperature, especially probes with detectors of large volumes. The probe with the detector of 4 cm 3 without IR illumination had energy resolution of 24.2 keV at 662 keV and of 12.5 keV with IR illumination. (authors)

  15. Growth and characterization of materials for infrared detectors and nonlinear optical switches; Proceedings of the Meeting, Orlando, FL, Apr. 2, 3, 1991 (United States)

    Longshore, Randolph E.; Baars, Jan W.

    Papers included in these proceedings are grouped under the topics of infrared material growth and characterization, infrared detector physics, and nonlinear optics. Attention is given to interface demarcation in Bridgman-Stockbarger crystal growth of II-VI compounds, growth of CdTe-CdMnTe heterostructures by molecular beam epitaxy, and a photoconductivity decay method for determining the minority carrier lifetime of p-type HgCdTe. Consideration is also given to anodic oxides on HgZnTe, the characterization of anodic fluoride films on Hg(1-x)Cd(x)Te, optical response in high-temperature superconducting thin films, and pyroelectric linear array IR detectors with CCD multiplexer. Other papers are on structural and optical properties of melt-processed calcium aluminate fibers, the preparation and characterization of a new thermistor material for thermistor bolometer, and photoemission from quantum-confined structure of nonlinear optical materials. (For individual items see A93-26893 to A93-26895)

  16. Kinetic inductance detectors for far-infrared spectroscopy

    International Nuclear Information System (INIS)

    Barlis, A.; Aguirre, J.; Stevenson, T.


    The star formation mechanisms at work in the early universe remain one of the major unsolved problems of modern astrophysics. Many of the luminous galaxies present during the period of peak star formation (at redshift of about 2.5) were heavily enshrouded in dust, which makes observing their properties difficult at optical wavelengths. However, many spectral lines exist at far-infrared wavelengths that serve as tracers of star formation. Here, we describe a detector system suitable for a balloon-borne spectroscopic intensity mapping experiment at far-infrared wavelengths. The system uses lumped-element kinetic inductance detectors (KIDs), which have the potential to achieve high sensitivity and low noise levels. KIDs consist of separate capacitive and inductive elements, and use the inductive element as the radiation absorber. We describe the design considerations, fabrication process, and readout scheme for a prototype LEKID array of 1600 pixels. - Highlights: • We describe a concept for a balloon-borne telescope for far-IR wavelengths. • Telescope would use high-sensitivity kinetic inductance detectors. • Design considerations and fabrication process for prototype detectors.

  17. Photoacoustic-based detector for infrared laser spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, L.; Palzer, S., E-mail: [Department of Microsystems Engineering-IMTEK, Laboratory for Gas Sensors, University of Freiburg, Georges-Köhler-Allee 102, Freiburg 79110 (Germany)


    In this contribution, we present an alternative detector technology for use in direct absorption spectroscopy setups. Instead of a semiconductor based detector, we use the photoacoustic effect to gauge the light intensity. To this end, the target gas species is hermetically sealed under excess pressure inside a miniature cell along with a MEMS microphone. Optical access to the cell is provided by a quartz window. The approach is particularly suitable for tunable diode laser spectroscopy in the mid-infrared range, where numerous molecules exhibit large absorption cross sections. Moreover, a frequency standard is integrated into the method since the number density and pressure inside the cell are constant. We demonstrate that the information extracted by our method is at least equivalent to that achieved using a semiconductor-based photon detector. As exemplary and highly relevant target gas, we have performed direct spectroscopy of methane at the R3-line of the 2v{sub 3} band at 6046.95 cm{sup −1} using both detector technologies in parallel. The results may be transferred to other infrared-active transitions without loss of generality.

  18. Kinetic inductance detectors for far-infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Barlis, A., E-mail: [University of Pennsylvania Department of Physics and Astronomy, Philadelphia, Pennsylvania (United States); Aguirre, J. [University of Pennsylvania Department of Physics and Astronomy, Philadelphia, Pennsylvania (United States); Stevenson, T. [NASA Goddard Space Flight Center, Greenbelt, Maryland (United States)


    The star formation mechanisms at work in the early universe remain one of the major unsolved problems of modern astrophysics. Many of the luminous galaxies present during the period of peak star formation (at redshift of about 2.5) were heavily enshrouded in dust, which makes observing their properties difficult at optical wavelengths. However, many spectral lines exist at far-infrared wavelengths that serve as tracers of star formation. Here, we describe a detector system suitable for a balloon-borne spectroscopic intensity mapping experiment at far-infrared wavelengths. The system uses lumped-element kinetic inductance detectors (KIDs), which have the potential to achieve high sensitivity and low noise levels. KIDs consist of separate capacitive and inductive elements, and use the inductive element as the radiation absorber. We describe the design considerations, fabrication process, and readout scheme for a prototype LEKID array of 1600 pixels. - Highlights: • We describe a concept for a balloon-borne telescope for far-IR wavelengths. • Telescope would use high-sensitivity kinetic inductance detectors. • Design considerations and fabrication process for prototype detectors.

  19. SAT's infrared equipment using second-generation detectors (United States)

    Siriex, Michel B.


    In 1982 SAT proposed for the first time a second generation detector in the design of FLIRs for the TRIGAT program, since then different types of IR equipment have been developed on the basis of this technology: (1) An infra-red seeker for the MICA missile. (2) Three types of IRST: VAMPIR MB for naval applications, SIRENE for the Army and OSF for the Rafale aircraft. (3) Three thermal imagers: Condor 1 for the mast mounted sight equipping the long range anti tank system, Tiger installed on the sight of the medium range antitank system, and Condor 2 for the pilot sight of the TRIGAT French-German helicopter. Infra-red detectors are MCT IR-CCD focal plane arrays developed by SOFRADIR with the objective of the best standardization possible in spite of different configurations and specifications for each program. In this paper, we intend to present the main features of this technology for these programs and the advantages obtained by comparison with the first generation in terms of performance. Industrialization of these products is starting now, and a specific effort has been made to standardize the components, especially the driving and read out electronics. A set of ASICs has been developed to make compact detection modules including a detector in his dewar, a cooling machine, and a proximity electronic.

  20. Development of HgCdTe large format MBE arrays and noise-free high speed MOVPE EAPD arrays for ground based NIR astronomy (United States)

    Finger, G.; Baker, I.; Downing, M.; Alvarez, D.; Ives, D.; Mehrgan, L.; Meyer, M.; Stegmeier, J.; Weller, H. J.


    Large format near infrared HgCdTe 2Kx2K and 4Kx4K MBE arrays have reached a level of maturity which meets most of the specifications required for near infrared (NIR) astronomy. The only remaining problem is the persistence effect which is device specific and not yet fully under control. For ground based multi-object spectroscopy on 40 meter class telescopes larger pixels would be advantageous. For high speed near infrared fringe tracking and wavefront sensing the only way to overcome the CMOS noise barrier is the amplification of the photoelectron signal inside the infrared pixel by means of the avalanche gain. A readout chip for a 320x256 pixel HgCdTe eAPD array will be presented which has 32 parallel video outputs being arranged in such a way that the full multiplex advantage is also available for small sub-windows. In combination with the high APD gain this allows reducing the readout noise to the subelectron level by applying nondestructive readout schemes with subpixel sampling. Arrays grown by MOVPE achieve subelectron readout noise and operate with superb cosmetic quality at high APD gain. Efforts are made to reduce the dark current of those arrays to make this technology also available for large format focal planes of NIR instruments offering noise free detectors for deep exposures. The dark current of the latest MOVPE eAPD arrays is already at a level adequate for noiseless broad and narrow band imaging in scientific instruments.

  1. Fifty years of HgCdTe at Texas Instruments and beyond (United States)

    Kinch, Michael A.


    Work on HgCdTe began at Texas Instruments in the early 1960s, and continued through 1997 when TI's defense business was sold first to Raytheon, and subsequently in 1998 to DRS Technologies. This presentation traces the history of HgCdTe's evolution throughout this timeframe to the present day, as viewed through the eyes of the author and several of his TI contemporaries who have survived the experience. The materials technology will be traced from the early days of bulk growth by the solid state recrystalization technique, through the traveling heater method of growth, to liquid phase epitaxy from large Te-rich melts, to vapor phase growth by molecular beam epitaxy and metal organic chemical vapor deposition. The evolution of detector device architectures at TI over the years will be discussed, from the early, successful days of photoconductors and the Common Module System, through the somewhat problematic and relatively unsuccessful foray into charge coupled and charge injection devices for 2nd generation FPAs for the Javelin program, to the outstandingly successful development of the vertically integrated photodiode (VIP) and high density VIP FPA architectures for mono-color and multi-color 3rd generation systems. The versatile, and unique nature of this infrared semiconductor materials system will be highlighted by reference to current work at DRS Technologies into electron avalanche photodiodes (EAPDs), for use in active/passive IR systems, and high operating temperature (HOT) detectors, which threaten to eventually offer BLIP photon detection at uncooled operating temperatures, over the whole IR spectrum from 1 to 12um.

  2. Advances in SELEX ES infrared detectors for space and astronomy (United States)

    Knowles, P.; Hipwood, L.; Baker, I.; Weller, H.


    Selex ES produces a wide range of infrared detectors from mercury cadmium telluride (MCT) and triglycine sulfate (TGS), and has supplied both materials into space programmes spanning a period of over 40 years. Current development activities that underpin potential future space missions include large format arrays for near- and short-wave infrared (NIR and SWIR) incorporating radiation-hard designs and suppression of glow. Improved heterostructures are aimed at the reduction of dark currents and avalanche photodiodes (APDs), and parallel studies have been undertaken for low-stress MCT array mounts. Much of this development work has been supported by ESA, UK Space, and ESO, and some has been performed in collaboration with the UK Astronomy Technology Centre and E2V. This paper focuses on MCT heterostructure developments and novel design elements in silicon read-out chips (ROICs). The 2048 x 2048 element, 17um pitch ROIC for ESA's SWIR array development forms the basis for the largest cooled infrared detector manufactured in Europe. Selex ES MCT is grown by metal organic vapour phase epitaxy (MOVPE), currently on 75mm diameter GaAs substrates. The MCT die size of the SWIR array is 35mm square and only a single array can be printed on the 75mm diameter wafer, utilising only 28% of the wafer area. The situation for 100mm substrates is little better, allowing only 2 arrays and 31% utilisation. However, low cost GaAs substrates are readily available in 150mm diameter and the MCT growth is scalable to this size, offering the real possibility of 6 arrays per wafer with 42% utilisation. A similar 2k x 2k ROIC is the goal of ESA's NIR programme, which is currently in phase 2 with a 1k x 1k demonstrator, and a smaller 320 x 256 ROIC (SAPHIRA) has been designed for ESO for the adaptive optics application in the VLT Gravity instrument. All 3 chips have low noise source-follower architecture and are enabled for MCT APD arrays, which have been demonstrated by ESO to be capable of

  3. Resonant detectors and focal plane arrays for infrared detection (United States)

    Choi, K. K.; Allen, S. C.; Sun, J. G.; DeCuir, E. A.


    We are developing resonator-QWIPs for narrowband and broadband long wavelength infrared detection. Detector pixels with 25 μm and 30 μm pitches were hybridized to fanout circuits and readout integrated electronics for radiometric measurements. With a low to moderate doping of 0.2-0.5 × 1018 cm-3 and a thin active layer thickness of 0.6-1.3 μm, we achieved a quantum efficiency between 25 and 37% and a conversion efficiency between of 15 and 20%. The temperature at which photocurrent equals dark current is about 65 K under F/2 optics for a cutoff wavelength up to 11 μm. The NEΔT of the FPAs is estimated to be 20 mK at 2 ms integration time and 60 K operating temperature. This good performance confirms the advantages of the resonator-QWIP approach.

  4. Advances in detector technologies for visible and infrared wavefront sensing (United States)

    Feautrier, Philippe; Gach, Jean-Luc; Downing, Mark; Jorden, Paul; Kolb, Johann; Rothman, Johan; Fusco, Thierry; Balard, Philippe; Stadler, Eric; Guillaume, Christian; Boutolleau, David; Destefanis, Gérard; Lhermet, Nicolas; Pacaud, Olivier; Vuillermet, Michel; Kerlain, Alexandre; Hubin, Norbert; Reyes, Javier; Kasper, Markus; Ivert, Olaf; Suske, Wolfgang; Walker, Andrew; Skegg, Michael; Derelle, Sophie; Deschamps, Joel; Robert, Clélia; Vedrenne, Nicolas; Chazalet, Frédéric; Tanchon, Julien; Trollier, Thierry; Ravex, Alain; Zins, Gérard; Kern, Pierre; Moulin, Thibaut; Preis, Olivier


    detector with a readout noise of 3 e (goal 1e) at 700 Hz frame rate. The LGSD is a scaling of the NGSD with 1760x1680 pixels and 3 e readout noise (goal 1e) at 700 Hz (goal 1000 Hz) frame rate. New technologies will be developed for that purpose: advanced CMOS pixel architecture, CMOS back thinned and back illuminated device for very high QE, full digital outputs with signal digital conversion on chip. In addition, the CMOS technology is extremely robust in a telescope environment. Both detectors will be used on the European ELT but also interest potentially all giant telescopes under development. Additional developments also started for wavefront sensing in the infrared based on a new technological breakthrough using ultra low noise Avalanche Photodiode (APD) arrays within the RAPID project. Developed by the SOFRADIR and CEA/LETI manufacturers, the latter will offer a 320x240 8 outputs 30 microns IR array, sensitive from 0.4 to 3.2 microns, with 2 e readout noise at 1500 Hz frame rate. The high QE response is almost flat over this wavelength range. Advanced packaging with miniature cryostat using liquid nitrogen free pulse tube cryocoolers is currently developed for this programme in order to allow use on this detector in any type of environment. First results of this project are detailed here. These programs are held with several partners, among them are the French astronomical laboratories (LAM, OHP, IPAG), the detector manufacturers (e2v technologies, Sofradir, CEA/LETI) and other partners (ESO, ONERA, IAC, GTC). Funding is: Opticon FP6 and FP7 from European Commission, ESO, CNRS and Université de Provence, Sofradir, ONERA, CEA/LETI and the French FUI (DGCIS).

  5. Chemical imaging of cotton fibers using an infrared microscope and a focal-plane array detector (United States)

    In this presentation, the chemical imaging of cotton fibers with an infrared microscope and a Focal-Plane Array (FPA) detector will be discussed. Infrared spectroscopy can provide us with information on the structure and quality of cotton fibers. In addition, FPA detectors allow for simultaneous spe...

  6. nBn Infrared Detector Containing Graded Absorption Layer (United States)

    Gunapala, Sarath D.; Ting, David Z.; Hill, Cory J.; Bandara, Sumith V.


    It has been proposed to modify the basic structure of an nBn infrared photodetector so that a plain electron-donor- type (n-type) semiconductor contact layer would be replaced by a graded n-type III V alloy semiconductor layer (i.e., ternary or quarternary) with appropriate doping gradient. The abbreviation nBn refers to one aspect of the unmodified basic device structure: There is an electron-barrier ("B" ) layer between two n-type ("n" ) layers, as shown in the upper part of the figure. One of the n-type layers is the aforementioned photon-absorption layer; the other n-type layer, denoted the contact layer, collects the photocurrent. The basic unmodified device structure utilizes minority-charge-carrier conduction, such that, for reasons too complex to explain within the space available for this article, the dark current at a given temperature can be orders of magnitude lower (and, consequently, signal-to-noise ratios can be greater) than in infrared detectors of other types. Thus, to obtain a given level of performance, less cooling (and, consequently, less cooling equipment and less cooling power) is needed. [In principle, one could obtain the same advantages by means of a structure that would be called pBp because it would include a barrier layer between two electron-acceptor- type (p-type) layers.] The proposed modifications could make it practical to utilize nBn photodetectors in conjunction with readily available, compact thermoelectric coolers in diverse infrared- imaging applications that could include planetary exploration, industrial quality control, monitoring pollution, firefighting, law enforcement, and medical diagnosis.

  7. Silicon Based Mid Infrared SiGeSn Heterostructure Emitters and Detectors (United States)


    AFRL-AFOSR-JP-TR-2016-0054 Silicon based mid infrared SiGeSn heterostrcture emitters and detectors Greg Sun UNIVERSITY OF MASSACHUSETTS Final Report... Silicon Based Mid Infrared SiGeSn Heterostructure Emitters and Detectors ” February 10, 2016 Principal Investigator: Greg Sun Engineering...diodes are incompatible with the CMOS process and therefore cannot be easily integrated with Si electronics . The GeSn mid IR detectors developed in

  8. Crosstalk of HgCdTe LWIR n-on-p diode arrays

    International Nuclear Information System (INIS)

    Sun Yinghui; Zhang Bo; Yu Meifang; Liao Qingjun; Zhang Yan; Wen Xin; Jiang Peilu; Hu Xiaoning; Dai Ning


    Crosstalk of HgCdTe long-wavelength infrared (LWIR) n-on-p diode arrays was measured using scanning laser microscopy. During the measurement, HgCdTe diode arrays with different diode pitches were frontside illuminated by a He-Ne laser at liquid nitrogen temperature and room temperature. The experimental results show that crosstalk between the nearest neighboring diodes decreases exponentially as the diode pitch increases, and the factors that affect the obtained crosstalk are presented and analyzed. Crosstalk out of the nominal diode area (optically sensitive area) is also measured and discussed.

  9. Impulse response measurement in the HgCdTe avalanche photodiode (United States)

    Singh, Anand; Pal, Ravinder


    HgCdTe based mid-wave infrared focal plane arrays (MWIR FPAs) are being developed for high resolution imaging and range determination of distant camouflaged targets. Effect of bandgap grading on the response time in the n+/ν/p+ HgCdTe electron avalanche photodiode (e-APD) is evaluated using impulse response measurement. Gain normalized dark current density of 2 × 10-9 A/cm2 at low reverse bias for passive mode and 2 × 10-4 A/cm2 at -8 V for active mode is measured in the fabricated APD device, yielding high gain bandwidth product of 2.4 THZ at the maximum gain. Diffusion of carriers is minimized to achieve transit time limited impulse response by introducing composition grading in the HgCdTe epilayer. The noise equivalent photon performance less than one is achievable in the FPA that is suitable for active cum passive imaging applications.

  10. High-Operating Temperature HgCdTe: A Vision for the Near Future (United States)

    Lee, D.; Carmody, M.; Piquette, E.; Dreiske, P.; Chen, A.; Yulius, A.; Edwall, D.; Bhargava, S.; Zandian, M.; Tennant, W. E.


    We review recent advances in the HgCdTe material quality and detector performance achieved at Teledyne using molecular beam epitaxy growth and the double-layer planar hetero-junction (DLPH) detector architecture. By using an un-doped, fully depleted absorber, Teledyne's DLPH architecture can be extended for use in high operating temperatures and other applications. We assess the potential achievable performance for long wavelength infrared (LWIR) hetero-junction p-lightly-doped n or p-intrinsic- n (p-i-n) detectors based on recently reported results for 10.7 μm cutoff 1 K × 1 K focal plane arrays (FPAs) tested at temperatures down to 30 K. Variable temperature dark current measurements show that any Shockley-Read-Hall currents in the depletion region of these devices have lifetimes that are reproducibly greater than 100 ms. Under the assumption of comparable lifetimes at higher temperatures, it is predicted that fully-depleted background radiation-limited performance can be expected for 10- μm cutoff detectors from room temperature to well below liquid nitrogen temperatures, with room-temperature dark current nearly 400 times lower than predicted by Rule 07. The hetero-junction p-i-n diode is shown to have numerous other significant potential advantages including minimal or no passivation requirements for pBn-like processing, low 1/ f noise, compatibility with small pixel pitch while maintaining high modulation transfer function, low crosstalk and good quantum efficiency. By appropriate design of the FPA dewar shielding, analysis shows that dark current can theoretically be further reduced below the thermal equilibrium radiative limit. Modeling shows that background radiation-limited LWIR HgCdTe operating with f/1 optics has the potential to operate within √2 of background-limited performance at 215 K. By reducing the background radiation by 2/3 using novel shielding methods, operation with a single-stage thermo-electric-cooler may be possible. If the

  11. Photon-Counting Microwave Kinetic Inductance Detectors (MKIDs) for High Resolution Far-Infrared Spectroscopy (United States)

    National Aeronautics and Space Administration — We are developing ultrasensitive Microwave Kinetic Inductance Detectors (MKIDs) for high resolution far-infrared spectroscopy applications, with a long-term goal of...

  12. Evaluation of Rockwell HgCdTe arrays for astronomical use (United States)

    Lebofsky, M. J.; Montgomery, E. F.; Kailey, W. F.


    The 32 x 32 HgCdTe array manufactured by Rockwell International was proven to be a highly competitive detector type for use at wavelengths shorter than 2.5 microns. The goal of a K=+16 sky survey using this array attached to the Steward Observatory Transit Telescope is clearly within reach. The detector material exhibits high quantum efficiency and low dark currents indicating that its usefulness may extend beyond its use with a CCD readout on groundbased telescopes.

  13. Infrared LED Array For Silicon Strip Detector Qualification

    CERN Document Server

    Dirkes, Guido; Hartmann, Frank; Heier, Stefan; Schwerdtfeger, Wolfgang; Waldschmitt, M; Weiler, K W; Weseler, Siegfried


    The enormous amount of silicon strip detector modules for the CMS tracker requires a test-sytem to allow qualification of each individual detector module and its front-end electronics within minutes. The objective is to test the detector with a physical signal. Signals are generated in the detector by illumination with lightpulses emitted by a LED at 950~nm and with a rise time of 10~ns. In order to avoid a detector moving, an array of 64 LEDs is used, overlaping the complete detector width. The total length of an array is 15~cm. The spot size of an individual LED is controlled by apertures to illuminate about 25 strips. Furthermore it is possible to simulate the high leakage current of irradiated sensors by constant illumination of the sensor. This provides an effective mean to identfy pinholes on a sensor.

  14. Infrared detectors and focal plane arrays; Proceedings of the Meeting, Orlando, FL, Apr. 18, 19, 1990 (United States)

    Dereniak, Eustace L.; Sampson, Robert E.


    The papers contained in this volume provide an overview of recent advances and the current state of developments in the field of infrared detectors and focal plane arrays. Topics discussed include nickel silicide Schottky-barrier detectors for short-wavelength infrared applications; high performance PtSi linear and focal plane arrays; and multispectral band Schottky-barrier IRSSD for remote-sensing applications. Papers are also presented on the performance of an Insi hybrid focal array; characterization of IR focal plane test stations; GaAs CCD readout for engineered bandgap detectors; and fire detection system for aircraft cargo bays.

  15. Novel Heterongineered Detectors for Multi-Color Infrared Sensing (United States)


    a) Sequential but collocated two-color detection capabilities of type II InAsGaSb SLS detector based on an nBn design and (b) Simultaneous and...captions: Figure 1. Heterostructure Schematic of (a) PbIbN Design, (b) Dual Color Detector Design with flat band energy lineups . Figure 2. (a) Spectral

  16. Overview of DRS uncooled VOx infrared detector development (United States)

    Li, Chuan; Han, C. J.; Skidmore, George


    Significant progress has been made over the past decade on uncooled focal plane array technologies and production capabilities. The detector pixel dimensions have continually decreased with an increase in pixel performance making large format, high-density array products affordable. In turn, this has resulted in the proliferation of uncooled IR detectors in commercial and military markets. Presently, uncooled detectors are widely used in firefighting, surveillance, industrial process monitoring, machine vision, and medical applications. Within the military arena, uncooled detectors are ubiquitous in Army soldier systems such as weapon sights, driver's viewers, and helmet-mounted sights. Uncooled detectors are also employed in airborne and ground surveillance sensors including unmanned aerial vehicles and robot vehicles.

  17. Charge distribution and response time for a modulation-doped extrinsic infrared detector (United States)

    Hadek, Victor


    The electric charge distribution and response time of a modulation-doped extrinsic infrared detector are determined. First, it is demonstrated theoretically that the photoconductive layer is effectively depleted of ionized majority-impurity charges so that scattering is small and mobility is high for photogenerated carriers. Then, using parameters appropriate to an actual detector, the predicted response time is 10 to the -8th to about 10 to the -9th s, which is much faster than comparable conventional detectors. Thus, the modulation-doped detector design would be valuable for heterodyne applications.

  18. NanoComposite Polymers for High Resolution Near Infrared Detectors (United States)

    National Aeronautics and Space Administration — Develop nanocomposite materials with tuned refractive index in the near infra red spectral range as an index-matched immersion lens for high resolution infra-red...

  19. Detector location selection based on VIP analysis in near-infrared detection of dural hematoma

    Directory of Open Access Journals (Sweden)

    Qiuming Sun


    Full Text Available Detection of dural hematoma based on multi-channel near-infrared differential absorbance has the advantages of rapid and non-invasive detection. The location and number of detectors around the light source are critical for reducing the pathological characteristics of the prediction model on dural hematoma degree. Therefore, rational selection of detector numbers and their distances from the light source is very important. In this paper, a detector position screening method based on Variable Importance in the Projection (VIP analysis is proposed. A preliminary modeling based on Partial Least Squares method (PLS for the prediction of dural position μa was established using light absorbance information from 30 detectors located 2.0–5.0 cm from the light source with a 0.1 cm interval. The mean relative error (MRE of the dural position μa prediction model was 4.08%. After VIP analysis, the number of detectors was reduced from 30 to 4 and the MRE of the dural position μa prediction was reduced from 4.08% to 2.06% after the reduction in detector numbers. The prediction model after VIP detector screening still showed good prediction of the epidural position μa. This study provided a new approach and important reference on the selection of detector location in near-infrared dural hematoma detection. Keywords: Detector location screening, Epidural hematoma detection, Variable importance in the projection

  20. Design of a multiband near-infrared sky brightness monitor using an InSb detector. (United States)

    Dong, Shu-Cheng; Wang, Jian; Tang, Qi-Jie; Jiang, Feng-Xin; Chen, Jin-Ting; Zhang, Yi-Hao; Wang, Zhi-Yue; Chen, Jie; Zhang, Hong-Fei; Jiang, Hai-Jiao; Zhu, Qing-Feng; Jiang, Peng; Ji, Tuo


    Infrared sky background level is an important parameter of infrared astronomy observations from the ground, particularly for a candidate site of an infrared capable observatory since low background level is required for such a site. The Chinese astronomical community is looking for a suitable site for a future 12 m telescope, which is designed for working in both optical and infrared wavelengths. However, none of the proposed sites has been tested for infrared observations. Nevertheless, infrared sky background measurements are also important during the design of infrared observing instruments. Based on the requirement, in order to supplement the current site survey data and guide the design of future infrared instruments, a multiband near-infrared sky brightness monitor (MNISBM) based on an InSb sensor is designed in this paper. The MNISBM consists of an optical system, mechanical structure and control system, detector and cooler, high gain readout electronics, and operational software. It is completed and tested in the laboratory. The results show that the sensitivity of the MNISBM meets the requirements of the measurement of near-infrared sky background level of several well-known astronomical infrared observing sites.

  1. Design of a multiband near-infrared sky brightness monitor using an InSb detector (United States)

    Dong, Shu-cheng; Wang, Jian; Tang, Qi-jie; Jiang, Feng-xin; Chen, Jin-ting; Zhang, Yi-hao; Wang, Zhi-yue; Chen, Jie; Zhang, Hong-fei; Jiang, Hai-jiao; Zhu, Qing-feng; Jiang, Peng; Ji, Tuo


    Infrared sky background level is an important parameter of infrared astronomy observations from the ground, particularly for a candidate site of an infrared capable observatory since low background level is required for such a site. The Chinese astronomical community is looking for a suitable site for a future 12 m telescope, which is designed for working in both optical and infrared wavelengths. However, none of the proposed sites has been tested for infrared observations. Nevertheless, infrared sky background measurements are also important during the design of infrared observing instruments. Based on the requirement, in order to supplement the current site survey data and guide the design of future infrared instruments, a multiband near-infrared sky brightness monitor (MNISBM) based on an InSb sensor is designed in this paper. The MNISBM consists of an optical system, mechanical structure and control system, detector and cooler, high gain readout electronics, and operational software. It is completed and tested in the laboratory. The results show that the sensitivity of the MNISBM meets the requirements of the measurement of near-infrared sky background level of several well-known astronomical infrared observing sites.

  2. Study and realization of a far infrared radiation detector

    International Nuclear Information System (INIS)

    Pereira, Daniel


    A F.I.R. dadiation detector (lambda = 337 μm) which makes use of the hot electron photoconductivity in InSb is described. The InSb crystal is cut in a special shape which allows high resistance (-7 KΩ) at liquid helium temperature without a magnetic field. In this way the detector can be used in the optimum point of the noise figure with a ultra-low noise pre-amplifier. A study is done to determine the sensitivity and the NEP (optical and electrical) which results respectively in 70 V/W and 10 -10 WHz sup(-1/2) for optical parameters. (Author) [pt

  3. Miniature Uncooled Infrared Sensitive Detectors for in Vivo Biomedical Imaging Applications

    Energy Technology Data Exchange (ETDEWEB)

    Datskos, P. G.; Demos, S. G.; Rajic, S.


    Broadband infrared (OR) radiation detectors have been developed using miniature, inexpensive, mass produced microcantilevers capable of detecting temperature differences as small as lea(-6) K. Microcantilevers made out of semiconductor materials can be used either as uncurled photon or thermal detectors. Mounted on a probe mm in diameter a number of microcantilevers can be accommodated in the working channel of existing endoscopes for in vivo proximity focus measurements inside the human body.

  4. Protection of High Ceiling Nuclear Facilities Using Photoelectric Sensors and Infrared Fire Detectors

    International Nuclear Information System (INIS)

    Wadoud, A.A.; El Eissawi, H.M.; Saleh, A.A.


    A variety of different security systems and components are commercially available and widely used. Before implementing a security system, it is important to understand the characteristics and requirements of the facility area to be protected. Technology and manufacturers of security devices are rapidly changing. It is necessary to use optimal security equipment suitable for the surrounding environment of the facility to be protected. Several security sensors can be used to protect the nuclear facilities, such as passive infrared detectors and glass breakage sensors, vibration detectors, and microwave sensors. This work introduces technical specifications, operation and method of installation for these detectors in nuclear facilities. Also a comparative study of different security sensors or equipment is provided. The photoelectric detectors and infrared fire beam smoke detectors are reliable, suitable and advanced security equipment. They can be used in special cases because of their advantages, this includes their long ranges and accuracy in performance. This paper presents a new concept for adapting the use infrared optical fire beam smoke detector as intrusion detection equipment in high ceiling buildings or towering height facilities. This is in addition to their main function, namely fire detection.The paper also provides a study for their types and installation method. Focus is made on the installation and operation method for two advanced security systems, and wireless control circuit for the overall system operation

  5. Electrical and optical properties of multiple quantum well structures and their applications to infrared detectors

    International Nuclear Information System (INIS)

    Helgesen, P.


    In this work the author investigate the subband nature of multiple quantum well structures by photoconductance spectroscopy, optical absorption measurements and tunneling experiments. Both interband and intraband transitions have been studied. The work is aimed at making an infrared detector using wide band gap semiconductors. 14 refs

  6. Interface engineered carbon nanotubes with SiO{sub 2} for flexible infrared detectors

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhenlong [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Gao, Min, E-mail: [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China); Pan, Taisong [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Wei, Xianhua [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang, Sichuan 621010 (China); Chen, Chonglin [Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX 78249 (United States); Department of Physics and the Texas Center for Superconductivity, University of Houston, Houston, TX 77204 (United States); Lin, Yuan, E-mail: [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China)


    Highlights: • Interface engineered carbon nanotubes with SiO{sub 2} is used to construct a kind of flexible infrared detector. • The interface between the MWCNTs and SiO{sub 2} could enhance the IR response speed. • Detector based on the integrated interface of MWCNTs and SiO{sub 2} has successfully detected the movements of the human fingers. - Abstract: Nitrogen-doped/non-doped carbon nanotubes (CNTs) were integrated on SiO{sub 2}/Si and PMMA substrates for understanding the infrared sensing mechanisms. The nanotube structures on SiO{sub 2} substrates exhibit a much shorter response time (about 40 ms) than those directly on PMMA substrates (about 1200 ms), indicating the interface effects between CNTs and the substrates. The infrared responses for both structures show a linear relationship with the light power density even at the radiation power as low as 0.1 mW/mm{sup 2}. Moreover, a new concept flexible IR detector was designed and fabricated by transferring the CNTs/SiO{sub 2} structure onto the PMMA substrate, which exhibits both short response time (50 ms) and good flexibility. The successful detection of human finger movements indicates the practical applications of the CNT-based detectors for the detection of weak thermal or far infrared radiation.

  7. Polymer-Ceramic Composite Materials for Pyroelectric Infrared Detectors: An Overview (United States)

    Aggarwal, M. D; Currie, J. R.; Penn, B. G.; Batra, A. K.; Lal, R. B.


    Ferroelectrics:Polymer composites can be considered an established substitute for conventional electroceramics and ferroelectric polymers. The composites have a unique blend of polymeric properties such as mechanical flexibility, high strength, formability, and low cost, with the high electro-active properties of ceramic materials. They have attracted considerable interest because of their potential use in pyroelectric infrared detecting devices and piezoelectric transducers. These flexible sensors and transducers may eventually be useful for their health monitoring applications for NASA crew launch vehicles and crew exploration vehicles being developed. In the light of many technologically important applications in this field, it is worthwhile to present an overview of the pyroelectric infrared detector theory, models to predict dielectric behavior and pyroelectric coefficient, and the concept of connectivity and fabrication techniques of biphasic composites. An elaborate review of Pyroelectric-Polymer composite materials investigated to date for their potential use in pyroelectric infrared detectors is presented.

  8. Hybrid active pixel sensors in infrared astronomy

    International Nuclear Information System (INIS)

    Finger, Gert; Dorn, Reinhold J.; Meyer, Manfred; Mehrgan, Leander; Stegmeier, Joerg; Moorwood, Alan


    Infrared astronomy is currently benefiting from three main technologies providing high-performance hybrid active pixel sensors. In the near infrared from 1 to 5 μm two technologies, both aiming for buttable 2Kx2K mosaics, are competing, namely InSb and HgCdTe grown by LPE or MBE on Al 2 O 3 , Si or CdZnTe substrates. Blocked impurity band Si:As arrays cover the mid infrared spectral range from 8 to 28 μm. Adaptive optics combined with multiple integral field units feeding high-resolution spectrographs drive the requirements for the array format of infrared sensors used at ground-based infrared observatories. The pixel performance is now approaching fundamental limits. In view of this development, a detection limit for the photon flux of the ideal detector will be derived, depending only on the temperature and the impedance of the detector. It will be shown that this limit is approximated by state of the art infrared arrays for long on-chip integrations. Different detector materials are compared and strategies to populate large focal planes are discussed. The need for the development of small-format low noise sensors for adaptive optics and interferometry will be pointed out

  9. Thermophysics modeling of an infrared detector cryochamber for transient operational scenario (United States)

    Singhal, Mayank; Singhal, Gaurav; Verma, Avinash C.; Kumar, Sushil; Singh, Manmohan


    An infrared detector (IR) is essentially a transducer capable of converting radiant energy in the infrared regime into a measurable form. The benefit of infrared radiation is that it facilitates viewing objects in dark or through obscured conditions by detecting the infrared energy emitted by them. One of the most significant applications of IR detector systems is for target acquisition and tracking of projectile systems. IR detectors also find widespread applications in the industry and commercial market. The performance of infrared detector is sensitive to temperatures and performs best when cooled to cryogenic temperatures in the range of nearly 120 K. However, the necessity to operate in such cryogenic regimes increases the complexity in the application of IR detectors. This entails a need for detailed thermophysics analysis to be able to determine the actual cooling load specific to the application and also due to its interaction with the environment. This will enable design of most appropriate cooling methodologies suitable for specific scenarios. The focus of the present work is to develop a robust thermo-physical numerical methodology for predicting IR cryochamber behavior under transient conditions, which is the most critical scenario, taking into account all relevant heat loads including radiation in its original form. The advantage of the developed code against existing commercial software (COMSOL, ANSYS, etc.), is that it is capable of handling gas conduction together with radiation terms effectively, employing a ubiquitous software such as MATLAB. Also, it requires much smaller computational resources and is significantly less time intensive. It provides physically correct results enabling thermal characterization of cryochamber geometry in conjunction with appropriate cooling methodology. The code has been subsequently validated experimentally as the observed cooling characteristics are found to be in close agreement with the results predicted using

  10. A new generation of small pixel pitch/SWaP cooled infrared detectors (United States)

    Espuno, L.; Pacaud, O.; Reibel, Y.; Rubaldo, L.; Kerlain, A.; Péré-Laperne, N.; Dariel, A.; Roumegoux, J.; Brunner, A.; Kessler, A.; Gravrand, O.; Castelein, P.


    Following clear technological trends, the cooled IR detectors market is now in demand for smaller, more efficient and higher performance products. This demand pushes products developments towards constant innovations on detectors, read-out circuits, proximity electronics boards, and coolers. Sofradir was first to show a 10μm focal plane array (FPA) at DSS 2012, and announced the DAPHNIS 10μm product line back in 2014. This pixel pitch is a key enabler for infrared detectors with increased resolution. Sofradir recently achieved outstanding products demonstrations at this pixel pitch, which clearly demonstrate the benefits of adopting 10μm pixel pitch focal plane array-based detectors. Both HD and XGA Daphnis 10μm products also benefit from a global video datapath efficiency improvement by transitioning to digital video interfaces. Moreover, innovative smart pixels functionalities drastically increase product versatility. In addition to this strong push towards a higher pixels density, Sofradir acknowledges the need for smaller and lower power cooled infrared detector. Together with straightforward system interfaces and better overall performances, latest technological advances on SWAP-C (Size, Weight, Power and Cost) Sofradir products enable the advent of a new generation of high performance portable and agile systems (handheld thermal imagers, unmanned aerial vehicles, light gimbals etc...). This paper focuses on those features and performances that can make an actual difference in the field.

  11. Stability of the spectral responsivity of cryogenically cooled InSb infrared detectors

    International Nuclear Information System (INIS)

    Theocharous, Evangelos


    The spectral responsivity of two cryogenically cooled InSb detectors was observed to drift slowly with time. The origin of these drifts was investigated and was shown to occur due to a water-ice thin film that was deposited onto the active areas of the cold detectors. The presence of the ice film (which is itself a dielectric film) modifies the transmission characteristics of the antireflection coatings deposited on the active areas of the detectors, thus giving rise to the observed drifts. The magnitude of the drifts was drastically reduced by evacuating the detector dewars while baking them at 50 deg. C for approximately 48 h. All InSb detectors have antireflection coatings to reduce the Fresnel reflections and therefore enhance their spectral responsivity. This work demonstrates that InSb infrared detectors should be evacuated and baked at least annually and in some cases (depending on the quality of the dewar and the measurement uncertainty required) more frequently. These observations are particularly relevant to InSb detectors mounted in dewars that use rubber O rings since the ingress of moisture was found to be particularly serious in this type of dewar

  12. Fast rise time IR detectors for lepton colliders

    International Nuclear Information System (INIS)

    Drago, A.; Bini, S.; Guidi, M. Cestelli; Marcelli, A.; Pace, E.


    Diagnostics is a fundamental issue for accelerators whose demands are continuously increasing. In particular bunch-by-bunch diagnostics is a key challenge for the latest generation of lepton colliders and storage rings. The Frascati Φ-factory, DAΦNE, colliding at 1.02 GeV in the centre of mass, hosts in the main rings few synchrotron radiation beamlines and two of them collect the synchrotron radiation infrared emission: SINBAD from the electron ring and 3+L from the positron ring. At DAΦNE each bucket is 2.7 ns long and particles are gathered in bunches emitting pulsed IR radiation, whose intensity in the long wavelength regime is directly proportional to the accumulated particles. Compact uncooled photoconductive HgCdTe detectors have been tested in both beamlines using dedicated optical layouts. Actually, the fast rise time of HgCdTe semiconductors give us the chance to test bunch-by-bunch devices for both longitudinal and transverse diagnostics. For the longitudinal case, single pixel detectors have been used, while for the transverse diagnostics, multi-pixel array detectors, with special custom design, are under test. This contribution will briefly describe the status of the research on fast IR detectors at DAΦNE, the results obtained and possible foreseen developments.

  13. A new test facility for the E-ELT infrared detector program (United States)

    Lizon, Jean Louis; Amico, Paola; Brinkmann, Martin; Delabre, Bernard; Finger, Gert; Guidolin, Ivan Maria; Guzman, Ronald; Hinterschuster, Renate; Ives, Derek; Klein, Barbara; Quattri, Marco


    During the development of the VLT instrumentation program, ESO acquired considerable expertise in the area of infrared detectors, their testing and optimizing their performance. This can mainly be attributed to a very competent team and most importantly to the availability of a very well suited test facility, namely, IRATEC. This test facility was designed more than 15 years ago, specifically for 1K × 1K detectors such as the Aladdin device, with a maximum field of only 30 mm square. Unfortunately, this facility is no longer suited for the testing of the new larger format detectors that are going to be used to equip the future E-ELT instruments. It is projected that over the next 20 years, there will be of the order of 50-100 very large format detectors to be procured and tested for use with E-ELT first and second generation instruments and VLT third generation instruments. For this reason ESO has initiated the in-house design and construction of a dedicated new IR detector arrays test facility: the Facility for Infrared Array Testing (FIAT). It will be possible to mount up to four 60 mm square detectors in the facility, as well as mosaics of smaller detectors. It is being designed to have a very low thermal background such that detectors with 5.3 μm cut-off material can routinely be tested. The paper introduces the most important use cases for which FIAT is designed: they range from performing routine performance measurements on acquired devices, optimization setups for custom applications (like spot scan intra-pixel response, persistence and surface reflectivity measurements), test of new complex operation modes (e.g. high speed subwindowing mode for low order sensing, flexure control, etc.) and the development of new tests and calibration procedures to support the scientific requirements of the E-ELT and to allow troubleshooting the unexpected challenges that arise when a new detector system is brought online. The facility is also being designed to minimize

  14. Evaluation of light detector surface area for functional Near Infrared Spectroscopy. (United States)

    Wang, Lei; Ayaz, Hasan; Izzetoglu, Meltem; Onaral, Banu


    Functional Near Infrared Spectroscopy (fNIRS) is an emerging neuroimaging technique that utilizes near infrared light to detect cortical concentration changes of oxy-hemoglobin and deoxy-hemoglobin non-invasively. Using light sources and detectors over the scalp, multi-wavelength light intensities are recorded as time series and converted to concentration changes of hemoglobin via modified Beer-Lambert law. Here, we describe a potential source for systematic error in the calculation of hemoglobin changes and light intensity measurements. Previous system characterization and analysis studies looked into various fNIRS parameters such as type of light source, number and selection of wavelengths, distance between light source and detector. In this study, we have analyzed the contribution of light detector surface area to the overall outcome. Results from Monte Carlo based digital phantoms indicated that selection of detector area is a critical system parameter in minimizing the error in concentration calculations. The findings here can guide the design of future fNIRS sensors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. An instrumentation amplifier based readout circuit for a dual element microbolometer infrared detector (United States)

    de Waal, D. J.; Schoeman, J.


    The infrared band is widely used in many applications to solve problems stretching over very diverse fields, ranging from medical applications like inflammation detection to military, security and safety applications employing thermal imaging in low light conditions. At the heart of these optoelectrical systems lies a sensor used to detect incident infrared radiation, and in the case of this work our focus is on uncooled microbolometers as thermal detectors. Microbolometer based thermal detectors are limited in sensitivity by various parameters, including the detector layout and design, operating temperature, air pressure and biasing that causes self heating. Traditional microbolometers use the entire membrane surface for a single detector material. This work presents the design of a readout circuit amplifier where a dual detector element microbolometer is used, rather than the traditional single element. The concept to be investigated is based on the principle that both elements will be stimulated with a similar incoming IR signal and experience the same resistive change, thus creating a common mode signal. However, such a common mode signal will be rejected by a differential amplifier, thus one element is placed within a negative resistance converter to create a differential mode signal that is twice the magnitude of the comparable single mode signal of traditional detector designs. An instrumentation amplifier is used for the final stage of the readout amplifier circuit, as it allows for very high common mode rejection with proper trimming of the Wheatstone bridge to compensate for manufacturing tolerance. It was found that by implementing the above, improved sensitivity can be achieved.

  16. Update on Linear Mode Photon Counting with the HgCdTe Linear Mode Avalanche Photodiode (United States)

    Beck, Jeffrey D.; Kinch, Mike; Sun, Xiaoli


    The behavior of the gain-voltage characteristic of the mid-wavelength infrared cutoff HgCdTe linear mode avalanche photodiode (e-APD) is discussed both experimentally and theoretically as a function of the width of the multiplication region. Data are shown that demonstrate a strong dependence of the gain at a given bias voltage on the width of the n- gain region. Geometrical and fundamental theoretical models are examined to explain this behavior. The geometrical model takes into account the gain-dependent optical fill factor of the cylindrical APD. The theoretical model is based on the ballistic ionization model being developed for the HgCdTe APD. It is concluded that the fundamental theoretical explanation is the dominant effect. A model is developed that combines both the geometrical and fundamental effects. The model also takes into account the effect of the varying multiplication width in the low bias region of the gain-voltage curve. It is concluded that the lower than expected gain seen in the first 2 × 8 HgCdTe linear mode photon counting APD arrays, and higher excess noise factor, was very likely due to the larger than typical multiplication region length in the photon counting APD pixel design. The implications of these effects on device photon counting performance are discussed.

  17. Detector with internal gain for short-wave infrared ranging applications (United States)

    Fathipour, Vala; Mohseni, Hooman


    Abstarct.Highly sensitive photon detectors are regarded as the key enabling elements in many applications. Due to the low photon energy at the short-wave infrared (SWIR), photon detection and imaging at this band are very challenging. As such, many efforts in photon detector research are directed toward improving the performance of the photon detectors operating in this wavelength range. To solve these problems, we have developed an electron-injection (EI) technique. The significance of this detection mechanism is that it can provide both high efficiency and high sensitivity at room temperature, a condition that is very difficult to achieve in conventional SWIR detectors. An EI detector offers an overall system-level sensitivity enhancement due to a feedback stabilized internal avalanche-free gain. Devices exhibit an excess noise of unity, operate in linear mode, require bias voltage of a few volts, and have a cutoff wavelength of 1700 nm. We review the material system, operating principle, and development of EI detectors. The shortcomings of the first-generation devices were addressed in the second-generation detectors. Measurement on second-generation devices showed a high-speed response of ˜6 ns rise time, low jitter of less than 20 ps, high amplification of more than 2000 (at optical power levels larger than a few nW), unity excess noise factor, and low leakage current (amplified dark current ˜10 nA at a bias voltage of -3 V and at room temperature. These characteristics make EI detectors a good candidate for high-resolution flash light detection and ranging (LiDAR) applications with millimeter scale depth resolution at longer ranges compared with conventional p-i-n diodes. Based on our experimentally measured device characteristics, we compare the performance of the EI detector with commercially available linear mode InGaAs avalanche photodiode (APD) as well as a p-i-n diode using a theoretical model. Flash LiDAR images obtained by our model show that the EI

  18. Numerical investigation of steady-state thermal behavior of an infrared detector cryo chamber

    Directory of Open Access Journals (Sweden)

    Singhal Mayank


    Full Text Available An infrared (IR detector is simply a transducer of radiant energy, converting radiant energy into a measurable form. Since radiation does not rely on visible light, it offers the possibility of seeing in the dark or through obscured conditions, by detecting the IR energy emitted by objects. One of the prime applications of IR detector systems for military use is in target acquisition and tracking of projectile systems. The IR detectors also have great potential in commercial market. Typically, IR detectors perform best when cooled to cryogenic temperatures in the range of nearly 120 K. However, the necessity to operate in such cryogenic regimes makes the application of IR detectors extremely complex. Further, prior to proceeding on to a full blown transient thermal analysis it is worthwhile to perform a steady-state numerical analysis for ascertaining the effect of variation in viz., material, gas conduction coefficient, h, emissivity, ε, on the temperature profile along the cryo chamber length. This would enable understanding the interaction between the cryo chamber and its environment. Hence, the present work focuses on the development of steady-state numerical models for thermal analysis of IR cryo chamber using MATLAB. The numerical results show that gas conduction coefficient has marked influence on the temperature profile of the cryo chamber whereas the emissivity has a weak effect. The experimental validation of numerical results has also been presented.

  19. Optical response of laser-doped silicon carbide for an uncooled midwave infrared detector. (United States)

    Lim, Geunsik; Manzur, Tariq; Kar, Aravinda


    An uncooled mid-wave infrared (MWIR) detector is developed by doping an n-type 4H-SiC with Ga using a laser doping technique. 4H-SiC is one of the polytypes of crystalline silicon carbide and a wide bandgap semiconductor. The dopant creates an energy level of 0.30  eV, which was confirmed by optical spectroscopy of the doped sample. This energy level corresponds to the MWIR wavelength of 4.21  μm. The detection mechanism is based on the photoexcitation of electrons by the photons of this wavelength absorbed in the semiconductor. This process modifies the electron density, which changes the refractive index, and, therefore, the reflectance of the semiconductor is also changed. The change in the reflectance, which is the optical response of the detector, can be measured remotely with a laser beam, such as a He-Ne laser. This capability of measuring the detector response remotely makes it a wireless detector. The variation of refractive index was calculated as a function of absorbed irradiance based on the reflectance data for the as-received and doped samples. A distinct change was observed for the refractive index of the doped sample, indicating that the detector is suitable for applications at the 4.21  μm wavelength.

  20. Examination of cotton fibers and common contaminants using an infrared microscope and a focal-plane array detector (United States)

    The chemical imaging of cotton fibers and common contaminants in fibers is presented. Chemical imaging was performed with an infrared microscope equipped with a Focal-Plane Array (FPA) detector. Infrared spectroscopy can provide us with information on the structure and quality of cotton fibers. In a...

  1. Fast infrared array spectrometer with a thermoelectrically cooled 160-element PbSe detector

    International Nuclear Information System (INIS)

    Ji Jun; Gore, Jay P.; Sivathanu, Yudaya R.; Lim, Jongmook


    A fast infrared array spectrometer (FIAS) with a thermoelectrically cooled 160-element PbSe detector was demonstrated using measurements of instantaneous infrared radiation intensities simultaneously over the 1.8-4.9 μm wavelength range at a sampling rate of 390 Hz. A three-point second-degree Lagrange interpolation polynomial was constructed to calibrate the FIAS because of the nonlinear response of the infrared array detector to the incident radiation beam. This calibration method gave excellent measurements of blackbody radiation spectra except for a narrow band at wavelength of 4.3 μm due to absorption by room carbon dioxide, which is one of the two major gas radiation peaks (2.7 and 4.3 μm) from the lean premixed hydrocarbon/air combustion products in the midinfrared spectrum. Therefore, the absorption coefficient of room carbon dioxide was conveniently measured on site with the blackbody reference source, and was used in the calibration of the FIAS and also in the calculations of the radiation spectra. Blackbody tests showed that this procedure was effective in correcting for the room carbon dioxide absorption in the radiation spectra measured by the FIAS. For an example of its application, the calibrated FIAS was used to measure spectral radiation intensities from three lean premixed laminar flames and a premixed turbulent jet flame for which reference data with a grating spectrometer were available for comparison. The agreement between the FIAS measurements and the reference data was excellent

  2. Design of InAs/GaSb superlattice infrared barrier detectors (United States)

    Delmas, M.; Rossignol, R.; Rodriguez, J. B.; Christol, P.


    Design of InAs/GaSb type-II superlattice (T2SL) infrared barrier detectors is theoretically investigated. Each part of the barrier structures is studied in order to achieve optimal device operation at 150 K and 77 K, in the midwave and longwave infrared domain, respectively. Whatever the spectral domain, nBp structure with a p-type absorbing zone and an n-type contact layer is found to be the most favourable detector architecture allowing a reduction of the dark-current associated with generation-recombination processes. The nBp structures are then compared to pin photodiodes. The MWIR nBp detector with 5 μm cut-off wavelength can operate up to 120 K, resulting in an improvement of 20 K on the operating temperature compared to the pin device. The dark-current density of the LWIR nBp device at 77 K is expected to be as low as 3.5 × 10-4 A/cm2 at 50 mV reverse bias, more than one decade lower than the usual T2SL photodiode. This result, for a device having cut-off wavelength at 12 μm, is at the state of the art compared to the well-known MCT 'rule 07'.

  3. Performance of Hg1-xCdxTe infrared focal plane array at elevated temperature (United States)

    Singh, Anand; Pal, Ravinder


    The simulated optical and electrical performance of the infrared HgCdTe focal plane array (FPA) for elevated operation temperature is reported. The depleted absorber layer is explored for equilibrium mode of operation up to 160 K. A resonant cavity is created to improve photon-matter interaction and hence, reduces the required absorption volume. The volume of the active region of HgCdTe detector is reduced by 70% in this manner. Dark current density is decreased without compromising the quantum efficiency. The effect of the reduced band filling effect leading to higher absorption coefficient and more efficient utilization of incident flux is employed. High quantum efficiency is achieved in a thin compositionally graded n+/ν/π/p HgCdTe photo-diode. This architecture helps to minimize the requirement of charge handling capacity in the CMOS read-out integrated circuit (ROIC) as the operation temperature is increased. Quantum efficiency ˜30% or above is shown to be sufficient for Noise Equivalent Temperature Difference (NETD) less than 20 mK with the reported design.

  4. Infrared Imaging of Cotton Fiber Bundles Using a Focal Plane Array Detector and a Single Reflectance Accessory

    Directory of Open Access Journals (Sweden)

    Michael Santiago Cintrón


    Full Text Available Infrared imaging is gaining attention as a technique used in the examination of cotton fibers. This type of imaging combines spectral analysis with spatial resolution to create visual images that examine sample composition and distribution. Herein, we report on the use of an infrared instrument equipped with a reflection accessory and an array detector system for the examination of cotton fiber bundles. Cotton vibrational spectra and chemical images were acquired by grouping pixels in the detector array. This technique reduced spectral noise and was employed to visualize cell wall development in cotton fibers bundles. Fourier transform infrared spectra reveal band changes in the C–O bending region that matched previous studies. Imaging studies were quick, relied on small amounts of sample and provided a distribution of the cotton fiber cell wall composition. Thus, imaging of cotton bundles with an infrared detector array has potential for use in cotton fiber examinations.

  5. Modified lead titanate thin films for pyroelectric infrared detectors on gold electrodes (United States)

    Ahmed, Moinuddin; Butler, Donald P.


    Pyroelectric infrared detectors provide the advantage of both a wide spectral response and dynamic range, which also has enabled systems to be developed with reduced size, weight and power consumption. This paper demonstrates the deposition of lead zirconium titanate (PZT) and lead calcium titanate (PCT) thin films for uncooled pyroelectric detectors with the utilization of gold electrodes. The modified lead titanate thin films were deposited by pulsed laser deposition on gold electrodes. The PZT and PCT thins films deposited and annealed at temperatures of 650 °C and 550 °C respectively demonstrated the best pyroelectric performance in this work. The thin films displayed a pyroelectric effect that increased with temperature. Poling of the thin films was carried out for a fixed time periods and fixed dc bias voltages at elevated temperature in order to increase the pyroelectric coefficient by establishing a spontaneous polarization of the thin films. Poling caused the pyroelectric current to increase one order of magnitude.

  6. Improvement of Infrared Detectors for Tissue Oximetry using Black Silicon Nanostructures

    DEFF Research Database (Denmark)

    Petersen, Søren Dahl; Davidsen, Rasmus Schmidt; Alcala, Lucia R.


    We present a nanostructured surface, made of dry etched black silicon, which lowers the reflectance for light incident at all angles. This surface is fabricated on infrared detectors used for tissue oximetry, where the detection of weak diffuse light signals is important. Monte Carlo simulations...... performed on a model of a neonatal head shows that approximately 60% of the injected light will be diffuse reflected. However, the change in diffuse reflected light due to the change in cerebral oxygenation is very low and the light will be completely isotropic scattered. The reflectance of the black...... in quantum efficiency for both normal incident light and light incident at 38°....

  7. Room temperature performance of mid-wavelength infrared InAsSb nBn detectors

    Energy Technology Data Exchange (ETDEWEB)

    Soibel, Alexander; Hill, Cory J.; Keo, Sam A.; Hoglund, Linda; Rosenberg, Robert; Kowalczyk, Robert; Khoshakhlagh, Arezou; Fisher, Anita; Ting, David Z.-Y.; Gunapala, Sarath D. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, California 91030 (United States)


    In this work, we investigate the high temperature performance of mid-wavelength infrared InAsSb-AlAsSb nBn detectors with cut-off wavelengths near 4.5 μm. The quantum efficiency of these devices is 35% without antireflection coatings and does not change with temperature in the 77–325 K temperature range, indicating potential for room temperature operation. The current generation of nBn detectors shows an increase of operational bias with temperature, which is attributed to a shift in the Fermi energy level in the absorber. Analysis of the device performance shows that operational bias and quantum efficiency of these detectors can be further improved. The device dark current stays diffusion limited in the 150 K–325 K temperature range and becomes dominated by generation-recombination processes at lower temperatures. Detector detectivities are D*(λ) = 1 × 10{sup 9} (cm Hz{sup 0.5}/W) at T = 300 K and D*(λ) = 5 × 10{sup 9} (cm Hz{sup 0.5}/W) at T = 250 K, which is easily achievable with a one stage TE cooler.

  8. Fast sub-electron detectors review for interferometry (United States)

    Feautrier, Philippe; Gach, Jean-Luc; Bério, Philippe


    New disruptive technologies are now emerging for detectors dedicated to interferometry. The detectors needed for this kind of applications need antonymic characteristics: the detector noise must be very low, especially when the signal is dispersed but at the same time must also sample the fast temporal characteristics of the signal. This paper describes the new fast low noise technologies that have been recently developed for interferometry and adaptive optics. The first technology is the Avalanche PhotoDiode (APD) infrared arrays made of HgCdTe. In this paper are presented the two programs that have been developed in that field: the Selex Saphira 320x256 [1] and the 320x255 RAPID detectors developed by Sofradir/CEA LETI in France [2], [3], [4]. Status of these two programs and future developments are presented. Sub-electron noise can now be achieved in the infrared using this technology. The exceptional characteristics of HgCdTe APDs are due to a nearly exclusive impaction ionization of the electrons, and this is why these devices have been called "electrons avalanche photodiodes" or e-APDs. These characteristics have inspired a large effort in developing focal plan arrays using HgCdTe APDs for low photon number applications such as active imaging in gated mode (2D) and/or with direct time of flight detection (3D imaging) and, more recently, passive imaging for infrared wave front correction and fringe tracking in astronomical observations. In addition, a commercial camera solution called C-RED, based on Selex Saphira and commercialized by First Light Imaging [5], is presented here. Some groups are also working with instruments in the visible. In that case, another disruptive technology is showing outstanding performances: the Electron Multiplying CCDs (EMCCD) developed mainly by e2v technologies in UK. The OCAM2 camera, commercialized by First Light Imaging [5], uses the 240x240 EMMCD from e2v and is successfully implemented on the VEGA instrument on the CHARA


    Directory of Open Access Journals (Sweden)

    I. V. Bilizhenko


    Full Text Available Subject of Research. The paper deals with synthesis of passive infra red (PIR detectors with enhanced detection capability of qualified intruder who uses different types of detection countermeasures: the choice of specific movement direction and disguise in infrared band. Methods. We propose an approach based on quasi-point model of qualified intruder. It includes: separation of model priority parameters, formation of partial detection patterns adapted to those parameters and multi channel signal processing. Main Results. Quasi-pointmodel of qualified intruder consisting of different fragments was suggested. Power density difference was used for model parameters estimation. Criteria were formulated for detection pattern parameters choice on the basis of model parameters. Pyroelectric sensor with nine sensitive elements was applied for increasing the signal information content. Multi-channel processing with multiple partial detection patterns was proposed optimized for detection of intruder's specific movement direction. Practical Relevance. Developed functional device diagram can be realized both by hardware and software and is applicable as one of detection channels for dual technology passive infrared and microwave detectors.

  10. Infrared (United States)

    Vollmer, M.


    'Infrared' is a very wide field in physics and the natural sciences which has evolved enormously in recent decades. It all started in 1800 with Friedrich Wilhelm Herschel's discovery of infrared (IR) radiation within the spectrum of the Sun. Thereafter a few important milestones towards widespread use of IR were the quantitative description of the laws of blackbody radiation by Max Planck in 1900; the application of quantum mechanics to understand the rotational-vibrational spectra of molecules starting in the first half of the 20th century; and the revolution in source and detector technologies due to micro-technological breakthroughs towards the end of the 20th century. This has led to much high-quality and sophisticated equipment in terms of detectors, sources and instruments in the IR spectral range, with a multitude of different applications in science and technology. This special issue tries to focus on a few aspects of the astonishing variety of different disciplines, techniques and applications concerning the general topic of infrared radiation. Part of the content is based upon an interdisciplinary international conference on the topic held in 2012 in Bad Honnef, Germany. It is hoped that the information provided here may be useful for teaching the general topic of electromagnetic radiation in the IR spectral range in advanced university courses for postgraduate students. In the most general terms, the infrared spectral range is defined to extend from wavelengths of 780 nm (upper range of the VIS spectral range) up to wavelengths of 1 mm (lower end of the microwave range). Various definitions of near, middle and far infrared or thermal infrared, and lately terahertz frequencies, are used, which all fall in this range. These special definitions often depend on the scientific field of research. Unfortunately, many of these fields seem to have developed independently from neighbouring disciplines, although they deal with very similar topics in respect of the

  11. Evaluation of Space Radiation Effects on HgCdTe Avalanche Photodiode Arrays for Lidar Applications (United States)

    Sun, Xiaoli; Abshire, James B.; Lauenstein, Jean-Marie; Sullivan, William III; Beck, Jeff; Hubbs, John E.


    We report the results from proton and gamma ray radiation testing of HgCdTe avalanche photodiode (APD) arrays developed by Leonardo DRS for space lidar detectors. We tested these devices with both approximately 60 MeV protons and gamma rays, with and without the read out integrated circuit (ROIC). We also measured the transient responses with the device fully powered and with the APD gain from unity to greater than 1000. The detectors produced a large current impulse in response to each proton hit but the response completely recovered within 1 microsecond. The devices started to have persistent damage at a proton fluence of 7e10 protons/cm2, equivalent to 10 krad(Si) total ionization dose. The dark current became much higher after the device was warmed to room temperature and cooled to 80K again, but it completely annealed after baking at 85 C for several hours. These results showed the HgCdTe APD arrays are suitable for use in space lidar for typical Earth orbiting and planetary missions provided that provisions are made to heat the detector chip to 85 C for several hours after radiation damage becomes evident that system performance is impacted.

  12. Analysis of the performance capability of an infrared interior intrusion detector

    International Nuclear Information System (INIS)

    Dunn, D.R.


    Component performances are required by the LLL assessment procedure for material control and accounting (MC and A) systems. Monitors are an example of an MC and A component whose functions are to process measurements or observations for purposes of detecting abnormalities. This report develops a methodology for characterizing the performance of a class of infrared (IR) interior intrusion monitors or detectors. The methodology is developed around a specific commercial IR detector, the InfrAlarm, manufactured by Barnes Engineering Company (Models 19-124 and 19-115A). Statistical detection models for computing probabilities of detection and false alarms were derived, and the performance capability of the InfrAlarm IR detector was shown using these measures. The results obtained in the performance analysis show that the detection capability of the InfrAlarm is excellent (approx. 1), with very low false alarm rates, for a wide range in target characteristics. These results should be representative and particularly for non-hostile environments

  13. Reliability studies of high operating temperature MCT photoconductor detectors (United States)

    Wang, Wei; Xu, Jintong; Zhang, Yan; Li, Xiangyang


    This paper concerns HgCdTe (MCT) infrared photoconductor detectors with high operating temperature. The near room temperature operation of detectors have advantages of light weight, less cost and convenient usage. Their performances are modest and they suffer from reliable problems. These detectors face with stability of the package, chip bonding area and passivation layers. It's important to evaluate and improve the reliability of such detectors. Defective detectors were studied with SEM(Scanning electron microscope) and microscopy. Statistically significant differences were observed between the influence of operating temperature and the influence of humidity. It was also found that humility has statistically significant influence upon the stability of the chip bonding and passivation layers, and the amount of humility isn't strongly correlated to the damage on the surface. Considering about the commonly found failures modes in detectors, special test structures were designed to improve the reliability of detectors. An accelerated life test was also implemented to estimate the lifetime of the high operating temperature MCT photoconductor detectors.

  14. Detecting an infrared photon within an hour. Transition-edge detector at ALPS-II

    Energy Technology Data Exchange (ETDEWEB)

    Dreyling-Eschweiler, Jan [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hamburg Univ. (Germany). Inst. fuer Experimentalphysik; Horns, Dieter [Hamburg Univ. (Germany). Inst. fuer Experimentalphysik; Collaboration: ALPS-II collaboration


    An essential design requirement of the ALPS-II experiment is the efficient detection of single photons with a very low instrumental background of 10 {mu}Hz. In 2011 the ALPS collaboration started to set up a TES detector (Transition-Edge Sensor) for ALPS-II, the second phase of the experiment. Since mid of 2013 the setup is ready for characterization in the ALPS laboratory: an ADR cryostat (Adiabatic Demagnetization Refrigerator) as millikelvin environment, a low noise SQUID (Superconducting Quantum Interference Device) with electronics for read-out and a fiber-coupled high-efficient TES for near-infrared photons as sensor. First measurements have shown a good discrimination between noise and 1064 nm signals.

  15. Study of polymorphous silicon as thermo-sensing film for infrared detectors

    International Nuclear Information System (INIS)

    Moreno, M.; Torres, A.; Ambrosio, R.; Torres, E.; Rosales, P.; Zuñiga, C.; Reyes-Betanzo, C.; Calleja, W.; De la Hidalga, J.; Monfil, K.


    In this work we have deposited and characterized pm-Si:H thin films obtained by plasma deposition. Our aim is to use pm-Si:H as thermo-sensing element for infrared (IR) detectors based on un-cooled microbolometers. We have studied the electrical characteristics of pm-Si:H that are figures of merit important for IR detection, as activation energy, thermal coefficient of resistance (TCR), room temperature conductivity (σ RT ) and responsivity under IR radiation. The influence of the substrate temperature (200 °C and 300 °C) on the pm-Si:H characteristics has been also studied. Our results shown that pm-Si:H is an excellent candidate to be used as thermo-sensing film for microbolometers, due to its large activation energy and TCR, with an improved σ RT .

  16. Detecting an infrared photon within an hour. Transition-edge detector at ALPS-II

    International Nuclear Information System (INIS)

    Dreyling-Eschweiler, Jan; Hamburg Univ.; Horns, Dieter


    An essential design requirement of the ALPS-II experiment is the efficient detection of single photons with a very low instrumental background of 10 μHz. In 2011 the ALPS collaboration started to set up a TES detector (Transition-Edge Sensor) for ALPS-II, the second phase of the experiment. Since mid of 2013 the setup is ready for characterization in the ALPS laboratory: an ADR cryostat (Adiabatic Demagnetization Refrigerator) as millikelvin environment, a low noise SQUID (Superconducting Quantum Interference Device) with electronics for read-out and a fiber-coupled high-efficient TES for near-infrared photons as sensor. First measurements have shown a good discrimination between noise and 1064 nm signals.

  17. Performances of a HGCDTE APD based direct detection lidar at 2 μm. Application to dial measurements (United States)

    Gibert, Fabien; Dumas, Arnaud; Rothman, Johan; Edouart, Dimitri; Cénac, Claire; Pellegrino, Jessica


    A lidar receiver with a direct detection chain adapted to a HgCdTe APD based detector with electric cooling is associated to a 2.05 μm Ho :YLF pulsed dual wavelength single mode transmitter to provide the first atmospheric lidar measurements using this technology. Experiments confirm the outstanding sensitivity of the detector and hightligth its huge potential for DIAL measurements of trace gas (CO2 and H2O) in this spectral domain. Performances of coherent vs direct detection at 2.05 μm is assessed.

  18. Performances of a HGCDTE APD based direct detection lidar at 2 μm. Application to dial measurements

    Directory of Open Access Journals (Sweden)

    Gibert Fabien


    Full Text Available A lidar receiver with a direct detection chain adapted to a HgCdTe APD based detector with electric cooling is associated to a 2.05 μm Ho :YLF pulsed dual wavelength single mode transmitter to provide the first atmospheric lidar measurements using this technology. Experiments confirm the outstanding sensitivity of the detector and hightligth its huge potential for DIAL measurements of trace gas (CO2 and H2O in this spectral domain. Performances of coherent vs direct detection at 2.05 μm is assessed.

  19. Infrared detectors and emitters on the basis of semiconductor quantum structures

    International Nuclear Information System (INIS)

    Kruck, P. R.


    Intersubband transitions in Si/SiGe and GaAs/AlGaAs semiconductor quantum structures have been investigated with respect to possible application as infrared detectors and emitters. Investigation of the polarization dependence of subband absorption in Si/SiGe quantum wells shows both transverse magnetic and transverse electric polarized excitations. Intersubband transitions to several excited states are identified by comparison with self-consistent Luttinger-Kohn type calculations. On the basis of these investigations a quantum well infrared photodetector operating between 3 and 8 μm with a detectivity as high as D*=2 x 10 10 cm Hz 1/2 W -1 under normal incidence illumination and at an operating temperature of T=77K is realized. The polarization dependence of the photoconductivity shows the importance of both the absorption and the vertical transport properties of the photoexcited carriers for the detection mechanism. On the basis of the GaAs/AlGaAs material system a unipolar quantum cascade light emitting diode (LED) has been realized. The LED operates at a wavelength of 6.9 μm. A detailed analysis of the electroluminescence spectra shows a linewidth as narrow as 14 meV at cryogenic temperatures, increasing to 20 meV at room temperature. For typical drive-current densities of 1 kA/cm 2 the optical output power lies in the ten nanowatt range. (author)

  20. A kilo-pixel imaging system for future space based far-infrared observatories using microwave kinetic inductance detectors

    NARCIS (Netherlands)

    Baselmans, J.J.A.; Bueno, J.; Yates, Stephen J.C.; Yurduseven, O.; Llombart Juan, N.; Karatsu, K.; Baryshev, A. M.; Ferrarini, L; Endo, A.; Thoen, D.J.; de Visser, P.J.; Janssen, R.M.J.; Murugesan, V.; Driessen, E.F.C.; Coiffard, G.; Martin-Pintado, J.; Hargrave, P.; Griffin, M.


    Aims. Future astrophysics and cosmic microwave background space missions operating in the far-infrared to millimetre part of the spectrum will require very large arrays of ultra-sensitive detectors in combination with high multiplexing factors and efficient low-noise and low-power readout systems.

  1. A kilo-pixel imaging system for future space based far-infrared observatories using microwave kinetic inductance detectors

    NARCIS (Netherlands)

    Baselmans, J. J. A.; Bueno, J.; Yates, S. J. C.; Yurduseven, O.; Llombart, N.; Karatsu, K.; Baryshev, A. M.; Ferrari, L.; Endo, A.; Thoen, D. J.; de Visser, P. J.; Janssen, R. M. J.; Murugesan, V.; Driessen, E. F. C.; Coiffard, G.; Martin-Pintado, J.; Hargrave, P.; Griffin, M.

    Aims: Future astrophysics and cosmic microwave background space missions operating in the far-infrared to millimetre part of the spectrum will require very large arrays of ultra-sensitive detectors in combination with high multiplexing factors and efficient low-noise and low-power readout systems.

  2. A novel, highly efficient cavity backshort design for far-infrared TES detectors (United States)

    Bracken, C.; de Lange, G.; Audley, M. D.; Trappe, N.; Murphy, J. A.; Gradziel, M.; Vreeling, W.-J.; Watson, D.


    In this paper we present a new cavity backshort design for TES (transition edge sensor) detectors which will provide increased coupling of the incoming astronomical signal to the detectors. The increased coupling results from the improved geometry of the cavities, where the geometry is a consequence of the proposed chemical etching manufacturing technique. Using a number of modelling techniques, predicted results of the performance of the cavities for frequencies of 4.3-10 THz are presented and compared to more standard cavity designs. Excellent optical efficiency is demonstrated, with improved response flatness across the band. In order to verify the simulated results, a scaled model cavity was built for testing at the lower W-band frequencies (75-100 GHz) with a VNA system. Further testing of the scale model at THz frequencies was carried out using a globar and bolometer via an FTS measurement set-up. The experimental results are presented, and compared to the simulations. Although there is relatively poor comparison between simulation and measurement at some frequencies, the discrepancies are explained by means of higher-mode excitation in the measured cavity which are not accounted for in the single-mode simulations. To verify this assumption, a better behaved cylindrical cavity is simulated and measured, where excellent agreement is demonstrated in those results. It can be concluded that both the simulations and the supporting measurements give confidence that this novel cavity design will indeed provide much-improved optical coupling for TES detectors in the far-infrared/THz band.

  3. Infrared focal plane array producibility and related materials; Proceedings of the Meeting, Orlando, FL, Apr. 20, 21, 1992 (United States)

    Balcerak, Ray; Pellegrini, Paul W.; Scribner, Dean A.

    The present conference discusses the commercial diversification of the U.S. IR detector industry's commercial diversification, HgCdTe focal-plane array (FPAs) manufacture, LPE of (Hg,Cd)Te FPAs, uncooled IR FPA detector producibility, a high performance staring IR camera, and novel technologies for FPA dewars. Also discussed are hybridizing FPAs, cryoprober test development, HgCdTe on Si for monolithic focal plane arrays, popcorn noise in linear InGaAs detector arrays, and the use of narrowband laser speckle for MTF characterization of CCDs. (No individual items are abstracted in this volume)

  4. Influence of infrared stimulation on spectroscopy characteristics of co-planar grid CdZnTe detectors

    International Nuclear Information System (INIS)

    Fjodorov, V.; Ivanov, V.; Loutchanski, A.


    It was previously found that illumination with monochromatic infrared (IR) light with wavelengths close to the absorption edge of the CdZnTe exert significant positive influence on the spectrometric characteristics of quasi-hemispherical CdZnTe detectors at room temperature. In this paper, preliminary results of IR stimulation on the spectrometric characteristics of coplanar-grid CdZnTe detectors as well as results of further studies of planar and quasi-hemispherical detectors are presented. Coplanar-grid detectors of 10 mm x 10 mm x 10 mm from Redlen Technologies and commercial available IR LEDs with different wavelengths of 800-1000 nm were used in the experiments. Influence of intensity and direction of IR illumination on the detector's characteristics was studied. Analysis of signals shapes from the preamplifiers outputs at registration of alpha particles showed that IR illumination leads to a change in the shapes of these signals. This may indicate changes in electric fields distributions. An improvement in energy resolution at gamma-energy of 662 keV was observed with quasi-hemispherical and co-planar detectors at the certain levels of IR illumination intensity. The most noticeable effect of IR stimulation was observed with quasi-hemispherical detectors. It is due with optimization of charge collection conditions in the quasi-hemispherical detectors under IT stimulation. (authors)

  5. Non-invasive characterization and quality assurance of silicon micro-strip detectors using pulsed infrared laser (United States)

    Ghosh, P.


    The Compressed Baryonic Matter (CBM) experiment at FAIR is composed of 8 tracking stations consisting of roughly 1300 double sided silicon micro-strip detectors of 3 different dimensions. For the quality assurance of prototype micro-strip detectors a non-invasive detector charaterization is developed. The test system is using a pulsed infrared laser for charge injection and characterization, called Laser Test System (LTS). The system is aimed to develop a set of characterization procedures which are non-invasive (non-destructive) in nature and could be used for quality assurances of several silicon micro-strip detectors in an efficient, reliable and reproducible way. The procedures developed (as reported here) uses the LTS to scan sensors with a pulsed infra-red laser driven by step motor to determine the charge sharing in-between strips and to measure qualitative uniformity of the sensor response over the whole active area. The prototype detector modules which are tested with the LTS so far have 1024 strips with a pitch of 58 μm on each side. They are read-out using a self-triggering prototype read-out electronic ASIC called n-XYTER. The LTS is designed to measure sensor response in an automatized procedure at several thousand positions across the sensor with focused infra-red laser light (spot size ≈ 12 μm, wavelength = 1060 nm). The pulse with a duration of ≈ 10 ns and power ≈ 5 mW of the laser pulse is selected such, that the absorption of the laser light in the 300 μm thick silicon sensor produces ≈ 24000 electrons, which is similar to the charge created by minimum ionizing particles (MIP) in these sensors. The laser scans different prototype sensors and various non-invasive techniques to determine characteristics of the detector modules for the quality assurance is reported.

  6. Evolution of miniature detectors and focal plane arrays for infrared sensors (United States)

    Watts, Louis A.


    Sensors that are sensitive in the infrared spectral region have been under continuous development since the WW2 era. A quest for the military advantage of 'seeing in the dark' has pushed thermal imaging technology toward high spatial and temporal resolution for night vision equipment, fire control, search track, and seeker 'homing' guidance sensing devices. Similarly, scientific applications have pushed spectral resolution for chemical analysis, remote sensing of earth resources, and astronomical exploration applications. As a result of these developments, focal plane arrays (FPA) are now available with sufficient sensitivity for both high spatial and narrow bandwidth spectral resolution imaging over large fields of view. Such devices combined with emerging opto-electronic developments in integrated FPA data processing techniques can yield miniature sensors capable of imaging reflected sunlight in the near IR and emitted thermal energy in the Mid-wave (MWIR) and longwave (LWIR) IR spectral regions. Robotic space sensors equipped with advanced versions of these FPA's will provide high resolution 'pictures' of their surroundings, perform remote analysis of solid, liquid, and gas matter, or selectively look for 'signatures' of specific objects. Evolutionary trends and projections of future low power micro detector FPA developments for day/night operation or use in adverse viewing conditions are presented in the following test.

  7. Detector Control and Data Acquisition for the Wide-Field Infrared Survey Telescope (WFIRST) with a Custom ASIC (United States)

    Smith, Brian S.; Loose, Markus; Alkire, Greg; Joshi, Atul; Kelly, Daniel; Siskind, Eric; Rossetti, Dino; Mah, Jonathan; Cheng, Edward; Miko, Laddawan; hide


    The Wide-Field Infrared Survey Telescope (WFIRST) will have the largest near-IR focal plane ever flown by NASA, a total of 18 4K x 4K devices. The project has adopted a system-level approach to detector control and data acquisition where 1) control and processing intelligence is pushed into components closer to the detector to maximize signal integrity, 2) functions are performed at the highest allowable temperatures, and 3) the electronics are designed to ensure that the intrinsic detector noise is the limiting factor for system performance. For WFIRST, the detector arrays operate at 90 to 100 K, the detector control and data acquisition functions are performed by a custom ASIC at 150 to 180 K, and the main data processing electronics are at the ambient temperature of the spacecraft, notionally approx.300 K. The new ASIC is the main interface between the cryogenic detectors and the warm instrument electronics. Its single-chip design provides basic clocking for most types of hybrid detectors with CMOS ROICs. It includes a flexible but simple-to-program sequencer, with the option of microprocessor control for more elaborate readout schemes that may be data-dependent. All analog biases, digital clocks, and analog-to-digital conversion functions are incorporated and are connected to the nearby detectors with a short cable that can provide thermal isolation. The interface to the warm electronics is simple and robust through multiple LVDS channels. It also includes features that support parallel operation of multiple ASICs to control detectors that may have more capability or requirements than can be supported by a single chip.

  8. Numerical simulation of crosstalk in reduced pitch HgCdTe photon-trapping structure pixel arrays. (United States)

    Schuster, Jonathan; Bellotti, Enrico


    We have investigated crosstalk in HgCdTe photovoltaic pixel arrays employing a photon trapping (PT) structure realized with a periodic array of pillars intended to provide broadband operation. We have found that, compared to non-PT pixel arrays with similar geometry, the array employing the PT structure has a slightly higher optical crosstalk. However, when the total crosstalk is evaluated, the presence of the PT region drastically reduces the total crosstalk; making the use of the PT structure not only useful to obtain broadband operation, but also desirable for reducing crosstalk in small pitch detector arrays.

  9. Scale invariant SURF detector and automatic clustering segmentation for infrared small targets detection (United States)

    Zhang, Haiying; Bai, Jiaojiao; Li, Zhengjie; Liu, Yan; Liu, Kunhong


    The detection and discrimination of infrared small dim targets is a challenge in automatic target recognition (ATR), because there is no salient information of size, shape and texture. Many researchers focus on mining more discriminative information of targets in temporal-spatial. However, such information may not be available with the change of imaging environments, and the targets size and intensity keep changing in different imaging distance. So in this paper, we propose a novel research scheme using density-based clustering and backtracking strategy. In this scheme, the speeded up robust feature (SURF) detector is applied to capture candidate targets in single frame at first. And then, these points are mapped into one frame, so that target traces form a local aggregation pattern. In order to isolate the targets from noises, a newly proposed density-based clustering algorithm, fast search and find of density peak (FSFDP for short), is employed to cluster targets by the spatial intensive distribution. Two important factors of the algorithm, percent and γ , are exploited fully to determine the clustering scale automatically, so as to extract the trace with highest clutter suppression ratio. And at the final step, a backtracking algorithm is designed to detect and discriminate target trace as well as to eliminate clutter. The consistence and continuity of the short-time target trajectory in temporal-spatial is incorporated into the bounding function to speed up the pruning. Compared with several state-of-arts methods, our algorithm is more effective for the dim targets with lower signal-to clutter ratio (SCR). Furthermore, it avoids constructing the candidate target trajectory searching space, so its time complexity is limited to a polynomial level. The extensive experimental results show that it has superior performance in probability of detection (Pd) and false alarm suppressing rate aiming at variety of complex backgrounds.

  10. Hydrogenated amorphous silicon photoresists for HgCdTe patterning

    Energy Technology Data Exchange (ETDEWEB)

    Hollingsworth, R.E.; DeHart, C.; Wang, L.; Dinan, J.H.; Johnson, J.N.


    A process to use a hydrogenated amorphous silicon (a-Si:H) film as a dry photoresist mask for plasma etching of HgCdTe has been demonstrated. The a-Si:H films were deposited using standard plasma enhanced chemical vapor deposition with pure silane as the source gas. X-ray photoelectron spectra show that virtually no oxide grows on the surface of an a-Si:H film after 3 hours in air, indicating that it is hydrogen passivated. Ultraviolet light frees hydrogen from the surface and enhances the oxide growth rate. A pattern of 60 micron square pixels was transferred from a contact mask to the surface of an a-Si:H film by ultraviolet enhanced oxidation in air. For the conditions used, the oxide thickness was 0.5--1.0 nm. Hydrogen plasmas were used to develop this pattern by removing the unexposed regions of the film. A hydrogen plasma etch selectivity between oxide and a-Si:H of greater than 500:1 allows patterns as thick as 700 nm to be generated with this very thin oxide. These patterns were transferred into HgCdTe by etching in an electron cyclotron resonance plasma. An etch selectivity between a-Si:H and HgCdTe of greater than 4:1 was observed after etching 2,500 nm into the HgCdTe. All of the steps are compatible with processing in vacuum.

  11. Infrared LED Enhanced Spectroscopic CdZnTe Detector Working under High Fluxes of X-rays

    Directory of Open Access Journals (Sweden)

    Jakub Pekárek


    Full Text Available This paper describes an application of infrared light-induced de-polarization applied on a polarized CdZnTe detector working under high radiation fluxes. We newly demonstrate the influence of a high flux of X-rays and simultaneous 1200-nm LED illumination on the spectroscopic properties of a CdZnTe detector. CdZnTe detectors operating under high radiation fluxes usually suffer from the polarization effect, which occurs due to a screening of the internal electric field by a positive space charge caused by photogenerated holes trapped at a deep level. Polarization results in the degradation of detector charge collection efficiency. We studied the spectroscopic behavior of CdZnTe under various X-ray fluxes ranging between 5 × 10 5 and 8 × 10 6 photons per mm 2 per second. It was observed that polarization occurs at an X-ray flux higher than 3 × 10 6 mm − 2 ·s − 1 . Using simultaneous illumination of the detector by a de-polarizing LED at 1200 nm, it was possible to recover X-ray spectra originally deformed by the polarization effect.

  12. Superconducting nanowire single-photon detectors (SNSPDs) on SOI for near-infrared range

    Energy Technology Data Exchange (ETDEWEB)

    Trojan, Philipp; Il' in, Konstantin; Henrich, Dagmar; Hofherr, Matthias; Doerner, Steffen; Siegel, Michael [Institut fuer Mikro- und Nanoelektronische Systeme (IMS), Karlsruher Institut fuer Technologie (KIT) (Germany); Semenov, Alexey [Institut fuer Planetenforschung, DLR, Berlin-Adlershof (Germany); Huebers, Heinz-Wilhelm [Institut fuer Planetenforschung, DLR, Berlin-Adlershof (Germany); Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin (Germany)


    Superconducting nanowire single-photon detectors are promising devices for photon detectors with high count rates, low dark count rates and low dead times. At wavelengths beyond the visible range, the detection efficiency of today's SNSPDs drops significantly. Moreover, the low absorption in ultra-thin detector films is a limiting factor over the entire spectral range. Solving this problem requires approaches for an enhancement of the absorption range in feeding the light to the detector element. A possibility to obtain a better absorption is the use of multilayer substrate materials for photonic waveguide structures. We present results on development of superconducting nanowire single-photon detectors made from niobium nitride on silicon-on-insulator (SOI) multilayer substrates. Optical and superconducting properties of SNSPDs on SOI will be discussed and compared with the characteristics of detectors on common substrates.

  13. Short-wave infrared barriode detectors using InGaAsSb absorption material lattice matched to GaSb

    Energy Technology Data Exchange (ETDEWEB)

    Craig, A. P.; Percy, B.; Marshall, A. R. J. [Physics Department, Lancaster University, Lancaster LA1 4YB (United Kingdom); Jain, M. [Amethyst Research Ltd., Kelvin Campus, West of Scotland Science Park, Glasgow G20 0SP (United Kingdom); Wicks, G.; Hossain, K. [Amethyst Research, Inc., 123 Case Circle, Ardmore, Oklahoma 73401 (United States); Golding, T. [Amethyst Research Ltd., Kelvin Campus, West of Scotland Science Park, Glasgow G20 0SP (United Kingdom); Amethyst Research, Inc., 123 Case Circle, Ardmore, Oklahoma 73401 (United States); McEwan, K.; Howle, C. [Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ (United Kingdom)


    Short-wave infrared barriode detectors were grown by molecular beam epitaxy. An absorption layer composition of In{sub 0.28}Ga{sub 0.72}As{sub 0.25}Sb{sub 0.75} allowed for lattice matching to GaSb and cut-off wavelengths of 2.9 μm at 250 K and 3.0 μm at room temperature. Arrhenius plots of the dark current density showed diffusion limited dark currents approaching those expected for optimized HgCdTe-based detectors. Specific detectivity figures of around 7×10{sup 10} Jones and 1×10{sup 10} Jones were calculated, for 240 K and room temperature, respectively. Significantly, these devices could support focal plane arrays working at higher operating temperatures.

  14. ICP etching for InAs-based InAs/GaAsSb superlattice long wavelength infrared detectors (United States)

    Huang, Min; Chen, Jianxin; Xu, Jiajia; Wang, Fangfang; Xu, Zhicheng; He, Li


    In this work, we study and report the dry etching processes for InAs-based InAs/GaAsSb strain-free superlattice long wavelength infrared (LWIR) detectors. The proper etching parameters were first obtained through the parametric studies of Inductively Coupled Plasma (ICP) etching of both InAs and GaSb bulk materials in Cl2/N2 plasmas. Then an InAs-based InAs/GaAsSb superlattice LWIR detector with PπN structure was fabricated by using the optimized etching parameters. At 80 K, the detector exhibits a 100% cut-off wavelength of 12 μm and a responsivity of 1.5 A/W. Moreover, the dark current density of the device under a bias of -200 mV reaches 5.5 × 10-4 A/cm2, and the R0A is 15 Ω cm2. Our results pave the way towards InAs-based superlattice LWIR detectors with better performances.

  15. Calibrated infrared ground/air radiometric spectrometer (United States)

    Silk, J. K.; Schildkraut, Elliot Robert; Bauldree, Russell S.; Goodrich, Shawn M.


    The calibrated infrared ground/air radiometric spectrometer (CIGARS) is a new high performance, multi-purpose, multi- platform Fourier transform spectrometer (FPS) sensor. It covers the waveband from 0.2 to 12 micrometer, has spectral resolution as fine as 0.3 cm-1, and records over 100 spectra per second. Two CIGARS units are being used for observations of target signatures in the air or on the ground from fixed or moving platforms, including high performance jet aircraft. In this paper we describe the characteristics and capabilities of the CIGARS sensor, which uses four interchangeable detector modules (Si, InGaAs, InSb, and HgCdTe) and two optics modules, with internal calibration. The data recording electronics support observations of transient events, even without precise information on the timing of the event. We present test and calibration data on the sensitivity, spectral resolution, stability, and spectral rate of CIGARS, and examples of in- flight observations of real targets. We also discuss plans for adapting CIGARS for imaging spectroscopy observations, with simultaneous spectral and spatial data, by replacing the existing detectors with a focal plane array (FPA).

  16. An Implant-Passivated Blocked Impurity Band Germanium Detector for the Far Infrared, Phase I (United States)

    National Aeronautics and Space Administration — We propose to investigate the feasibility of fabricating a germanium blocked-impurity-band (BIB) detector using a novel process which will enable us to: 1- fabricate...

  17. An Implant-Passivated Blocked Impurity Band Germanium Detector for the Far Infrared, Phase II (United States)

    National Aeronautics and Space Administration — We propose to fabricate a germanium blocked-impurity-band (BIB) detector using a novel process which will enable us to: 1- fabricate a suitably-doped active layer...

  18. Characterisation of an inhomogeneously irradiated microstrip detector using a fine spot infrared laser

    CERN Document Server

    Casse, G; Bowcock, T J V; Greenall, A; Phillips, JP; Turner, PR; Wright, V


    A prototype silicon microstrip detector for the LHCb vertex locator (VELO) has been partially irradiated using a 24 GeV/c proton beam at the CERN-PS accelerator. The detector possesses a radial strip geometry designed to measure the azimuthal coordinate (Phi) of tracks within the VELO. The peak fluence received by the detector was measured to be 4.6×10 14 p/cm 2 though the non-uniform nature of the exposure left part of the detector unirradiated. The inhomogeneous irradiation introduced a damage profile in the detector approximating to that expected in the VELO. High irradiation gradients are important to study as they can modify the electric field within the silicon. Of special interest are changes in the component of the electric field parallel to the strip plane but perpendicular to the strips which lead to systematic shifts in the reconstructed cluster position. If these (flux and position dependent) shifts are sufficiently large they could contribute to a degraded spatial resolution of the detector. In ...

  19. Advanced far infrared blocked impurity band detectors based on germanium liquid phase epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Christopher Sean [Univ. of California, Berkeley, CA (United States)


    This research has shown that epilayers with residual impurity concentrations of 5 x 1013 cm-3 can be grown by producing the purest Pb available in the world. These epilayers have extremely low minority acceptor concentrations, which is ideal for fabrication of IR absorbing layers. The Pb LPE growth of Ge also has the advantageous property of gettering Cu from the epilayer and the substrate. Epilayers have been grown with intentional Sb doping for IR absorption on lightly doped substrates. This research has proven that properly working Ge BIB detectors can be fabricated from the liquid phase as long as pure enough solvents are available. The detectors have responded at proper wavelengths when reversed biased even though the response did not quite reach minimum wavenumbers. Optimization of the Sb doping concentration should further decrease the photoionization energy of these detectors. Ge BIB detectors have been fabricated that respond to 60 cm-1 with low responsivity. Through reduction of the minority residual impurities, detector performance has reached responsivities of 1 A/W. These detectors have exhibited quantum efficiency and NEP values that rival conventional photoconductors and are expected to provide a much more sensitive tool for new scientific discoveries in a number of fields, including solid state studies, astronomy, and cosmology.

  20. Mid infrared resonant cavity detectors and lasers with epitaxial lead-chalcogenides (United States)

    Zogg, H.; Rahim, M.; Khiar, A.; Fill, M.; Felder, F.; Quack, N.


    Wavelength tunable emitters and detectors in the mid-IR wavelength region allow applications including thermal imaging and gas spectroscopy. One way to realize such tunable devices is by using a resonant cavity. By mechanically changing the cavity length with MEMS mirror techniques, the wavelengths may be tuned over a considerable range. Resonant cavity enhanced detectors (RCED) are sensitive at the cavity resonance only. They may be applied for low resolution spectroscopy, and, when arrays of such detectors are realized, as multicolour IR-FPA or "IR-AFPA", adaptive focal plane arrays. We report the first room temperature mid-IR VECSEL (vertical external cavity surface emitting laser) with a wavelength above 3 μm. The active region is just 850 nm PbSe, followed by a 2.5 pair Bragg mirror. Output power is > 10 mW at RT.

  1. MTG infrared sounder detection chain: first radiometric test results (United States)

    Dumestier, D.; Pistone, F.; Dartois, T.; Blazquez, E.


    Europe's next fleet of geostationary meteorological satellites, MeteoSat Third Generation, will introduce new functions in addition to continuity of high-resolution meteorological data. The atmosphere Infrared Sounder (IRS), as high -end instrument, is part of this challenging program. IRS principle is a Fourier Transform Interferometer, which allows recomposing atmospheric spectrum after infrared photons detection. Transmission spectrums will be used to support numerical weather prediction. IRS instrument is able to offer full disk coverage in one hour, an on-ground resolution of 4 by 4 km, in two spectral bands (MWIR: 1600 to 2175cm-1 and LWIR: 700 to 1210cm-1) with a spectral resolution of 0.6cm-1. Among critical technologies and processes, IRS detection chain shall offer outstanding characteristics in terms of radiometric performance like Signal to Noise Ratio (SNR), dynamic range and linearity. Selected detectors are HgCdTe two-dimensions arrays, cooled at 55 Kelvins, hybridized on snapshot silicon read-out circuit at 160x160 format. Video electronics present 16 bits resolution, and the whole detection chain (Detectors and electronics) permits to reach SNR between 2 000 and 10 000 as requested by the application. Radiometric onground test results performed on design representative detection chains are presented and are confirming the challenging phase A design choices.

  2. 77 FR 16925 - Medical Devices; Neurological Devices; Classification of the Near Infrared Brain Hematoma Detector (United States)


    ... notification, prior to marketing the device, which contains information about the NIR Brain Hematoma Detector...), and the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4). Executive Orders 12866 and 13563 direct..., environmental, public health and safety, and other advantages; distributive impacts; and equity). The Agency...

  3. Large-format 17μm high-end VOx μ-bolometer infrared detector (United States)

    Mizrahi, U.; Argaman, N.; Elkind, S.; Giladi, A.; Hirsh, Y.; Labilov, M.; Pivnik, I.; Shiloah, N.; Singer, M.; Tuito, A.; Ben-Ezra, M.; Shtrichman, I.


    Long range sights and targeting systems require a combination of high spatial resolution, low temporal NETD, and wide field of view. For practical electro-optical systems it is hard to support these constraints simultaneously. Moreover, achieving these needs with the relatively low-cost Uncooled μ-Bolometer technology is a major challenge in the design and implementation of both the bolometer pixel and the Readout Integrated Circuit (ROIC). In this work we present measured results from a new, large format (1024×768) detector array, with 17μm pitch. This detector meets the demands of a typical armored vehicle sight with its high resolution and large format, together with low NETD of better than 35mK (at F/1, 30Hz). We estimate a Recognition Range for a NATO target of better than 4 km at all relevant atmospheric conditions, which is better than standard 2nd generation scanning array cooled detector. A new design of the detector package enables improved stability of the Non-Uniformity Correction (NUC) to environmental temperature drifts.

  4. Increasing sensitivity and angle-of-view of mid-wave infrared detectors by integration with dielectric microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Kenneth W., E-mail:; Astratov, Vasily N., E-mail: [Department of Physics and Optical Science, Center for Optoelectronics and Optical Communications, University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001 (United States); Air Force Research Laboratory, Sensors Directorate, Wright Patterson AFB, Ohio 45433 (United States); UES, Dayton, Ohio 45433 (United States); Abolmaali, Farzaneh [Department of Physics and Optical Science, Center for Optoelectronics and Optical Communications, University of North Carolina at Charlotte, Charlotte, North Carolina 28223-0001 (United States); Duran, Joshua M.; Ariyawansa, Gamini; Limberopoulos, Nicholaos I. [Air Force Research Laboratory, Sensors Directorate, Wright Patterson AFB, Ohio 45433 (United States); Urbas, Augustine M. [Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Ohio 45433 (United States)


    We observed up to 100 times enhancement of sensitivity of mid-wave infrared photodetectors in the 2–5 μm range by using photonic jets produced by sapphire, polystyrene, and soda-lime glass microspheres with diameters in the 90–300 μm range. By finite-difference time-domain (FDTD) method for modeling, we gain insight into the role of the microspheres refractive index, size, and alignment with respect to the detector mesa. A combination of enhanced sensitivity with angle-of-view (AOV) up to 20° is demonstrated for individual photodetectors. It is proposed that integration with microspheres can be scaled up for large focal plane arrays, which should provide maximal light collection efficiencies with wide AOVs, a combination of properties highly attractive for imaging applications.

  5. Near-infrared Raman spectroscopy using a diode laser and CCD detector for tissue diagnostics

    International Nuclear Information System (INIS)

    Gustafsson, U.


    This paper surveys the possibility to observe high-quality NIR Raman spectra of both fluorescent and non-fluorescent samples with the use of a diode laser, a fibre optic sample, a single spectrometer and a charge-coupled device (CCD) detector. A shifted excitation difference technique was implemented for removing the broad-band fluorescence emission from Raman spectra of the highly fluorescent samples. Raman spectra of 1.4-dioxane, toluene, rhodamine 6G, and HITCI in the 640 to 1840 cm -1 spectral region and 1.4-dioxane and toluene in the 400 to 3400 cm -1 spectral region have been recorded. The results open the field of sensitive tissue characterisation and the possibility of optical biopsy in vivo by using NIR Raman spectroscopy with fibre optic sampling, a single spectrometer, and a CCD detector

  6. Modified electron beam induced current technique for in(Ga)As/InAsSb superlattice infrared detectors (United States)

    Yoon, N.; Reyner, C. J.; Ariyawansa, G.; Duran, J. M.; Scheihing, J. E.; Mabon, J.; Wasserman, D.


    Electron beam induced current (EBIC) measurements provide a powerful tool for characterizing semiconductor based materials and devices. By measuring the current generated by the electron beam of a scanning electron microscope (SEM), EBIC allows us to extract the minority carrier diffusion length (L) and the surface recombination velocity to diffusivity ratio (S/D) of a material. When combined with information on minority carrier lifetime (τ), for instance from time-resolved photoluminescence measurements, the minority carrier mobility of the material can be extracted. However, the EBIC technique relies heavily on the accurate modeling of the carrier generation and collection process. Traditionally, this was achieved using a combination of empirical analytical expressions (and later Monte Carlo simulations) for carrier generation and analytical diffusion/recombination expressions for carrier collection. This approach introduces significant uncertainties into the extracted material parameters. Here, we present a numerical approach to EBIC modeling which improves the spatial resolution of our model, while also retaining information regarding the relative EBIC signal as a function of incident beam energies and currents. We apply this technique to investigate the temperature dependent minority carrier mobility of InAs/InAsSb and InGaAs/InAsSb strained layer superlattice infrared detectors and compare our results to the values obtained using external quantum efficiency measurements of the same samples. Our approach not only allows for an improvement in the uncertainty of the extracted material parameters, but also offers insight into the material and device behavior as a function of nonequilibrium carrier concentration. The technique presented here offers potentially improved characterization of not only infrared detectors, but a range of semiconductor-based devices.

  7. Depth sensitivity and source-detector separations for near infrared spectroscopy based on the Colin27 brain template.

    Directory of Open Access Journals (Sweden)

    Gary E Strangman

    Full Text Available Understanding the spatial and depth sensitivity of non-invasive near-infrared spectroscopy (NIRS measurements to brain tissue-i.e., near-infrared neuromonitoring (NIN - is essential for designing experiments as well as interpreting research findings. However, a thorough characterization of such sensitivity in realistic head models has remained unavailable. In this study, we conducted 3,555 Monte Carlo (MC simulations to densely cover the scalp of a well-characterized, adult male template brain (Colin27. We sought to evaluate: (i the spatial sensitivity profile of NIRS to brain tissue as a function of source-detector separation, (ii the NIRS sensitivity to brain tissue as a function of depth in this realistic and complex head model, and (iii the effect of NIRS instrument sensitivity on detecting brain activation. We found that increasing the source-detector (SD separation from 20 to 65 mm provides monotonic increases in sensitivity to brain tissue. For every 10 mm increase in SD separation (up to ~45 mm, sensitivity to gray matter increased an additional 4%. Our analyses also demonstrate that sensitivity in depth (S decreases exponentially, with a "rule-of-thumb" formula S=0.75*0.85(depth. Thus, while the depth sensitivity of NIRS is not strictly limited, NIN signals in adult humans are strongly biased towards the outermost 10-15 mm of intracranial space. These general results, along with the detailed quantitation of sensitivity estimates around the head, can provide detailed guidance for interpreting the likely sources of NIRS signals, as well as help NIRS investigators design and plan better NIRS experiments, head probes and instruments.

  8. Modelling of illuminated current–voltage characteristics to evaluate leakage currents in long wavelength infrared mercury cadmium telluride photovoltaic detectors

    International Nuclear Information System (INIS)

    Gopal, Vishnu; Qiu, WeiCheng; Hu, Weida


    The current–voltage characteristics of long wavelength mercury cadmium telluride infrared detectors have been studied using a recently suggested method for modelling of illuminated photovoltaic detectors. Diodes fabricated on in-house grown arsenic and vacancy doped epitaxial layers were evaluated for their leakage currents. The thermal diffusion, generation–recombination (g-r), and ohmic currents were found as principal components of diode current besides a component of photocurrent due to illumination. In addition, both types of diodes exhibited an excess current component whose growth with the applied bias voltage did not match the expected growth of trap-assisted-tunnelling current. Instead, it was found to be the best described by an exponential function of the type, I excess  = I r0  + K 1 exp (K 2 V), where I r0 , K 1 , and K 2 are fitting parameters and V is the applied bias voltage. A study of the temperature dependence of the diode current components and the excess current provided the useful clues about the source of origin of excess current. It was found that the excess current in diodes fabricated on arsenic doped epitaxial layers has its origin in the source of ohmic shunt currents. Whereas, the source of excess current in diodes fabricated on vacancy doped epitaxial layers appeared to be the avalanche multiplication of photocurrent. The difference in the behaviour of two types of diodes has been attributed to the difference in the quality of epitaxial layers

  9. Improved optical properties and detectivity of an uncooled silicon carbide mid-wave infrared optical detector with increased dopant concentration

    International Nuclear Information System (INIS)

    Lim, Geunsik; Kar, Aravinda; Manzur, Tariq


    An n-type 4H-SiC substrate is doped with gallium using a laser doping technique and its optical response is investigated at the mid-wave infrared (MWIR) wavelength 4.21 μm as a function of the dopant concentration. The dopant creates a p-type energy level of 0.3 eV, which is the energy of a photon corresponding to the MWIR wavelength 4.21 μm. Therefore, Ga-doped SiC can be used as an uncooled MWIR detector because an optical signal was obtained at this wavelength when the sample was at room temperature. The energy level of the Ga dopant in the substrate was confirmed by optical absorption spectroscopy. Secondary ion mass spectroscopy (SIMS) of the doped samples revealed an enhancement in the solid solubility of Ga in the substrate when doping is carried out by increasing the number of laser scans. A higher dopant concentration increases the number of holes in the dopant energy level, enabling photoexcitation of more electrons from the valence band by the incident MWIR photons. The detector performance improves as the dopant concentration increases from 1.15 × 10 19 to 6.25 × 10 20 cm −3 . The detectivity of the optical photodetector is found to be 1.07 × 10 10 cm Hz 1/2 W −1 for the case of doping with four laser passes. (paper)

  10. Shot-Noise-Limited Dual-Beam Detector for Atmospheric Trace-Gas Monitoring with Near-Infrared Diode Lasers (United States)

    Durry, Georges; Pouchet, Ivan; Amarouche, Nadir; Danguy, Théodore; Megie, Gerard


    A dual-beam detector is used to measure atmospheric trace species by differential absorption spectroscopy with commercial near-infrared InGaAs laser diodes. It is implemented on the Spectrom tre Diodes Laser Accordables, a balloonborne tunable diode laser spectrometer devoted to the in situ monitoring of CH 4 and H 2 O. The dual-beam detector is made of simple analogical subtractor circuits combined with InGaAs photodiodes. The detection strategy consists in taking the balanced analogical difference between the reference and the sample signals detected at the input and the output of an open optical multipass cell to apply the full dynamic range of the measurements (16 digits) to the weak molecular absorption information. The obtained sensitivity approaches the shot-noise limit. With a 56-m optical cell, the detection limit obtained when the spectra is recorded within 8 ms is 10 4 (expressed in absorbance units). The design and performances of both a simple substractor and an upgraded feedback substractor circuit are discussed with regard to atmospheric in situ CH 4 absorption spectra measured in the 1.653- m region. Mixing ratios are obtained from the absorption spectra by application of a nonlinear least-squares fit to the full molecular line shape in conjunction with in situ P and T measurements.

  11. 3D-Printing of inverted pyramid suspending architecture for pyroelectric infrared detectors with inhibited microphonic effect (United States)

    Xu, Qing; Zhao, Xiangyong; Li, Xiaobing; Deng, Hao; Yan, Hong; Yang, Linrong; Di, Wenning; Luo, Haosu; Neumann, Norbert


    A sensitive chip with ultralow dielectric loss based on Mn doped PMNT (71/29) has been proposed for high-end pyroelectric devices. The dielectric loss at 1 kHz is 0.005%, one order lower than the minimum value reported so far. The detective figure of merit (Fd) is up to 92.6 × 10-5 Pa-1/2 at 1 kHz and 53.5 × 10-5 Pa-1/2 at 10 Hz, respectively. In addition, an inverted pyramid suspending architecture for supporting the sensitive chip has been designed and manufactured by 3D printing technology. The combination of this sensitive chip and the proposed suspending architecture largely enhances the performance of the pyroelectric detectors. The responsivity and specific detectivity are 669,811 V/W and 3.32 × 109 cm Hz1/2/W at 10 Hz, respectively, 1.9 times and 1.5 times higher than those of the highest values in literature. Furthermore, the microphonic effect can be largely inhibited according to the theoretical and experimental analysis. This architecture will have promising applications in high-end and stable pyroelectric infrared detectors.

  12. Infrared detectors and arrays; Proceedings of the Meeting, Orlando, FL, Apr. 6, 7, 1988

    International Nuclear Information System (INIS)

    Dereniak, E.L.


    The papers contained in this volume provide an overview of recent advances in theoretical and experimental research related to IR detector materials and arrays. The major subject areas covered include IR Schottky barrier silicide arrays, HdCdTe developments, SPRITE technology, superlattice or bandgap-engineered devices, extrinsic silicon technology, indium antimonide technology, and pyroelectric arrays. Papers are presented on time division multiplexed time delay integration, spatial noise in staring IR focal plane arrays, pyroelectrics in a harsh environment, and testing of focal plane arrays

  13. Advances in research and development homojunction and quantum-well infrared detectors

    CERN Document Server

    Francombe, Maurice H


    Physics of Thin Films is one of the longest running continuing series in thin film science, consisting of twenty volumes since 1963. The series contains quality studies of the properties of various thinfilms materials and systems.In order to be able to reflect the development of today''s science and to cover all modern aspects of thin films, the series, starting with Volume 20, has moved beyond the basic physics of thin films. It now addresses the most important aspects of both inorganic and organic thin films, in both their theoretical as well as technological aspects. Therefore, in order to reflect the modern technology-oriented problems, the title has been slightly modified from Physics of Thin Films to Thin Films.Key Features* Discusses the latest research about structure, physics, and infrared photoemissive behavior of heavily doped silicon homojunctions and Ge and GaAs-based alloy junctions* Reviews the current status of SiGe/Si quantum wells for infrared detection* Discusses key developments in the gro...

  14. Impact of three-dimensional geometry on the performance of isolated electron-injection infrared detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fathipour, Vala; Jang, Sung Jun; Nia, Iman Hassani; Mohseni, Hooman, E-mail: [Bio-Inspired Sensors and Optoelectronics Laboratory, Northwestern University, 2145 Sheridan Rd, Evanston, Illinois 60208 (United States)


    We present a quantitative study of the influence of three-dimensional geometry of the isolated electron–injection detectors on their characteristics. Significant improvements in the device performance are obtained as a result of scaling the injector diameter with respect to the trapping/absorbing layer diameters. Devices with about ten times smaller injector area with respect to the trapping/absorbing layer areas show more than an order of magnitude lower dark current, as well as an order of magnitude higher optical gain compared with devices of same size injector and trapping/absorbing layer areas. Devices with 10 μm injector diameter and 30 μm trapping/absorbing layer diameter show an optical gain of ∼2000 at bias voltage of −3 V with a cutoff wavelength of 1700 nm. Analytical expressions are derived for the electron-injection detector optical gain to qualitatively explain the significance of scaling the injector with respect to the absorber.

  15. Far infrared thermal detectors for laser radiometry using a carbon nanotube array

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, John H.; Lee, Bob; Grossman, Erich N.


    We present a description of a 1.5 mm long, vertically aligned carbon nanotube array (VANTA) on a thermopile and separately on a pyroelectric detector. Three VANTA samples, having average lengths of 40 {mu}m, 150 {mu}m, and 1.5 mm were evaluated with respect to reflectance at a laser wavelength of 394 {mu}m(760 GHz), and we found that the reflectance decreases substantially with increasing tube length, ranging from 0.38 to 0.23 to 0.01, respectively. The responsivity of the thermopile by electrical heating (98.4 mA/W) was equal to that by optical heating (98.0 mA/W) within the uncertainty of the measurement. We analyzed the frequency response and temporal response and found a thermal decay period of 500 ms, which is consistent with the specific heat of comparable VANTAs in the literature. The extremely low (0.01) reflectance of the 1.5 mm VANTAs and the fact that the array is readily transferable to the detector's surface is, to our knowledge, unprecedented.

  16. Microfiber-coupled superconducting nanowire single-photon detector for near-infrared wavelengths. (United States)

    You, Lixing; Wu, Junjie; Xu, Yingxin; Hou, Xintong; Fang, Wei; Li, Hao; Zhang, Weijun; Zhang, Lu; Liu, Xiaoyu; Tong, Limin; Wang, Zhen; Xie, Xiaoming


    High-performance superconducting nanowire single-photon detectors (SNSPDs) have facilitated numerous experiments and applications, particularly in the fields of modern quantum optics and quantum communication. Two kinds of optical coupling methods have thus far been developed for SNSPDs: one produces standard fiber-coupled SNSPDs in which the fibers vertically illuminate the meandered nanowires; the other produces waveguide-coupled SNSPDs in which nanowires are fabricated on the surface of a waveguide that guides photons, and the fibers are coupled to the waveguide. In this paper, we report on first experimental demonstration of a new type of SNSPD that is coupled with a microfiber (MF). Photons are guided by the MF and are evanescently absorbed by the nanowires of the SNSPD when the MF is placed on top of superconducting NbN nanowires. Room-temperature optical experiments indicated that this device has a coupling efficiency of up to 90% when a 1.3 μm-diameter MF is used for light with wavelength of 1550 nm. We were also able to demonstrate that our MF-coupled detector achieved system detection efficiencies of 50% and 20% at incident wavelengths of 1064 and 1550 nm, respectively, for a 2 μm-diameter MF at 2.2K. We expect that MF-coupled SNSPDs may show both high efficiency and broadband characteristics upon optimization and will be used for various novel applications, such as micro/nano-fiber optics.

  17. Split detector

    International Nuclear Information System (INIS)

    Cederstrand, C.N.; Chism, H.R.


    A gas analyzer is disclosed which provides a dual channel capability for the simultaneous determination of the presence and concentration of two gases in a stream of sample gas and which has a single infrared source, a single sample cell, two infrared bandpass filters, and two infrared detectors. A separator between the filters and detectors prevents interchange of radiation between the filters. The separator is positioned by fitting it in a slot

  18. Experimental study on the Stirling refrigerator for cooling of infrared detector

    Energy Technology Data Exchange (ETDEWEB)

    Park, S. J.; Hong, Y. J.; Kim, H. B.; Koh, D. Y. [Korea Institute of Machinery and Materials, Taejon (Korea, Republic of); Kim, J. H.; Yu, B. K. [Wooyoung, Seoul (Korea, Republic of)


    A Stirling cryocooler is relatively compact, reliable, commercially available, and uses helium as a working fluid. The FPFD Stirling cryocooler consists of two compressor pistons driven by linear motors which makes pressure waves and a pneumatically driven displacer piston with regenerator. A Free Piston and Free Displacer (FPFD) Stirling cryocooler for cooling infrared and cryo-sensors is currently under development at KIMM(Korea Institute of Machinery and Materials). In order to evaluate the feasibility of using a linear motor driving cryocooler, prototype Stirling cryocooler with a nominal cooling capacity of 0.5W at 80K was designed, fabricated and tested. The prototype has achieved no load temperature of 51K and cooling power of 0.33W.

  19. Experimental study on the Stirling refrigerator for cooling of infrared detector

    International Nuclear Information System (INIS)

    Park, S. J.; Hong, Y. J.; Kim, H. B.; Koh, D. Y.; Kim, J. H.; Yu, B. K.


    A Stirling cryocooler is relatively compact, reliable, commercially available, and uses helium as a working fluid. The FPFD Stirling cryocooler consists of two compressor pistons driven by linear motors which makes pressure waves and a pneumatically driven displacer piston with regenerator. A Free Piston and Free Displacer (FPFD) Stirling cryocooler for cooling infrared and cryo-sensors is currently under development at KIMM(Korea Institute of Machinery and Materials). In order to evaluate the feasibility of using a linear motor driving cryocooler, prototype Stirling cryocooler with a nominal cooling capacity of 0.5W at 80K was designed, fabricated and tested. The prototype has achieved no load temperature of 51K and cooling power of 0.33W

  20. Development of ultra pure germanium epi layers for blocked impurity band far infrared detectors

    International Nuclear Information System (INIS)

    Lutz, M.P.


    The main goals of this paper are: (1) To develop a low-pressure CVD (LPCVD) process that allows epitaxial growth at lower temperatures. Lower temperatures will allow the achievement of a sharp dopant profile at the substrate/epi-layer interface. Less out-diffusion from the substrate would allow the use of thinner epitaxial layers, which would lead to a larger depletion width in the photoactive region. LPCVD also avoids, to a great extent, gas-phase nucleation, which would cause Ge particulates to fall onto the wafer surface during growth. (2) To reduce high levels of oxygen and copper present at the wafer interface, as observed by secondary ion mass spectroscopy (SIMS). In order to achieve high-quality epitaxial layers, it is imperative that the substrate surface be of excellent quality. (3) To make and test detectors, after satisfactory epitaxial layers have been made

  1. Design issues of a low cost lock-in amplifier readout circuit for an infrared detector (United States)

    Scheepers, L.; Schoeman, J.


    In the past, high resolution thermal sensors required expensive cooling techniques making the early thermal imagers expensive to operate and cumbersome to transport, limiting them mainly to military applications. However, the introduction of uncooled microbolometers has overcome many of earlier problems and now shows great potential for commercial optoelectric applications. The structure of uncooled microbolometer sensors, especially their smaller size, makes them attractive in low cost commercial applications requiring high production numbers with relatively low performance requirements. However, the biasing requirements of these microbolometers cause these sensors to generate a substantial amount of noise on the output measurements due to self-heating. Different techniques to reduce this noise component have been attempted, such as pulsed biasing currents and the use of blind bolometers as common mode reference. These techniques proved to either limit the performance of the microbolometer or increase the cost of their implementation. The development of a low cost lock-in amplifier provides a readout technique to potentially overcome these challenges. High performance commercial lock-in amplifiers are very expensive. Using this as a readout circuit for a microbolometer will take away from the low manufacturing cost of the detector array. Thus, the purpose of this work was to develop a low cost readout circuit using the technique of phase sensitive detection and customizing this as a readout circuit for microbolometers. The hardware and software of the readout circuit was designed and tested for improvement of the signal-to-noise ratio (SNR) of the microbolometer signal. An optical modulation system was also developed in order to effectively identify the desired signal from the noise with the use of the readout circuit. A data acquisition and graphical user interface sub system was added in order to display the signal recovered by the readout circuit. The readout

  2. Modeling and optimization of InGaAs infrared photovoltaic detectors

    CERN Document Server

    Piotrowski, J; Reginski, K


    The performance of In sub x Ga sub 1 sub - sub x As detectors operating in the 2-3.4 mu m spectral range and temperature of 300 K has been analyzed theoretically as a function of wavelength, band gap and doping level with special emphasis on 2-2.5 mu m and 3-3.5 mu m atmospheric window devices. The calculations show that the dominant generation-recombination mechanism in p-type, intrinsic and in a lightly doped n-type InGaAs is the spin split-off band Auger process (AS). Since the AS generation increases with the square of the hole concentration, the minimum thermal generation and the best performance can be obtained using moderately doped n-type material as the absorber region of a photovoltaic device. In principle, the ultimate performance can be achieved in the optimized homojunction devices with relatively thick n-type absorber region forming n-p junction with a thin p-type material. N-type doping of absorber region of InGaAs photodiodes at 300 K changes from 1x10 sup 1 sup 4 to 5.2x10 sup 1 sup 5 cm sup ...

  3. Data compressive paradigm for multispectral sensing using tunable DWELL mid-infrared detectors. (United States)

    Jang, Woo-Yong; Hayat, Majeed M; Godoy, Sebastián E; Bender, Steven C; Zarkesh-Ha, Payman; Krishna, Sanjay


    While quantum dots-in-a-well (DWELL) infrared photodetectors have the feature that their spectral responses can be shifted continuously by varying the applied bias, the width of the spectral response at any applied bias is not sufficiently narrow for use in multispectral sensing without the aid of spectral filters. To achieve higher spectral resolutions without using physical spectral filters, algorithms have been developed for post-processing the DWELL's bias-dependent photocurrents resulting from probing an object of interest repeatedly over a wide range of applied biases. At the heart of these algorithms is the ability to approximate an arbitrary spectral filter, which we desire the DWELL-algorithm combination to mimic, by forming a weighted superposition of the DWELL's non-orthogonal spectral responses over a range of applied biases. However, these algorithms assume availability of abundant DWELL data over a large number of applied biases (>30), leading to large overall acquisition times in proportion with the number of biases. This paper reports a new multispectral sensing algorithm to substantially compress the number of necessary bias values subject to a prescribed performance level across multiple sensing applications. The algorithm identifies a minimal set of biases to be used in sensing only the relevant spectral information for remote-sensing applications of interest. Experimental results on target spectrometry and classification demonstrate a reduction in the number of required biases by a factor of 7 (e.g., from 30 to 4). The tradeoff between performance and bias compression is thoroughly investigated. © 2011 Optical Society of America

  4. Chinese Military Evaluation of a Portable Near-Infrared Detector of Traumatic Intracranial Hematomas. (United States)

    Liang, Chun-Yang; Yang, Yang; Shen, Chun-Sen; Wang, Hai-Jiang; Liu, Nai-Ming; Wang, Zhi-Wen; Zhu, Feng-Lei; Xu, Ru-Xiang


    Secondary brain injury is the main cause of mortality from traumatic brain injury (TBI). One hallmark of TBI is intracranial hemorrhage, which occurs in 40-50% of severe TBI cases. Early identification of intracranial hematomas in TBI patients allows early surgical evacuation and can reduce the case fatality rate of TBI. As pre-hospital care is the weakest part of Chinese emergency care, there is an urgent need for a capability to detect brain hematomas early. In China, in addition to preventing injuries and diseases in military staff and in enhancing the military armed forces during war, military medicine participates in actions such as emergency public health crises, natural disasters, emerging conflicts, and anti-terrorist campaigns during peacetime. The purpose of this observational study is to evaluate in the Chinese military general hospital the performance of a near-infrared (NIR)-based portable device, developed for US Military, in the detection of traumatic intracranial hematomas. The endpoint of the study was a description of the test characteristics (sensitivity, specificity, and positive and negative predictive values [NPV]) of the portable NIR-based device in identification of hematomas within its detection limits (volume >3.5 mL and depth hematoma detection in patients sustaining TBI. Data were collected in the People's Liberation Army General Hospital in Beijing using the NIR device at the time of CT scans, which were performed to evaluate suspected TBI. One hundred and twenty seven patients were screened, and 102 patients were included in the per protocol population. Of the 102 patients, 24 were determined by CT scan to have intracranial hemorrhage. The CT scans were read by an independent neuroradiologist who was blinded to the NIR measurements. The NIR device demonstrated sensitivity of 100% (95% confidence intervals [CI] 82.8-100%) and specificity of 93.6% (95%CI 85-97.6%) in detecting intracranial hematomas larger than 3.5 mL in volume and that

  5. SWIR HgCdTe avalanche photiode focal plane array performances evaluation (United States)

    de Borniol, E.; Rothman, J.; Salveti, F.; Feautrier, P.


    One of the main challenges of modern astronomical instruments like adaptive optics (AO) systems or fringe trackers is to deal with the very low photons flux detection scenarios. The typical timescale of atmospheric turbulences being in the range of some tens of milliseconds, infrared wavefront sensors for AO systems needs frame rates higher than 1 KHz leading to integration times lower than 1 ms. This integration time associated with a low irradiance results in a few number of integrated photons per frame per pixel. To preserve the information coming from this weak signal, the focal plane array (FPA) has to present a low read out noise, a high quantum efficiency and a low dark current. Up to now, the output noise of high speed near infrared sensors is limited by the silicon read out circuit noise. The use of HgCdTe avalanche photodiodes with high gain at moderate reverse bias and low excess noise seems then a logical way to reduce the impact of the read noise on images signal to noise ratio. These low irradiance passive imaging applications with integration times in the millisecond range needs low photodiode dark current and low background current. These requirements lead to the choice of the photodiode cut off wavelength. The short wave infrared (SWIR) around 3 μm is a good compromise between the gain that can be obtain for a given APD bias and the background and dark current. The CEA LETI HgCdTe APD technology, and a fine analysis of the gain curve characteristic are presented in [1] and won't be detailed here. The response time of the APD is also a key factor for a high frame rate FPA. This parameter has been evaluated in [2] and the results shows cut off frequencies in the GHz range. In this communication we report the performances of a SWIR APD FPA designed and fabricated by CEA LETI and SOFRADIR for astrophysical applications. This development was made in the frame of RAPID, a 4 years R&D project funded by the French FUI (Fond Unique Interministériel). This

  6. Performance of the HIRS/2 instrument on TIROS-N. [High Resolution Infrared Radiation Sounder (United States)

    Koenig, E. W.


    The High Resolution Infrared Radiation Sounder (HIRS/2) was developed and flown on the TIROS-N satellite as one means of obtaining atmospheric vertical profile information. The HIRS/2 receives visible and infrared spectrum radiation through a single telescope and selects 20 narrow radiation channels by means of a rotating filter wheel. A passive radiant cooler provides an operating temperature of 106.7 K for the HgCdTe and InSb detectors while the visible detector operates at instrument frame temperature. Low noise amplifiers and digital processing provide 13 bit data for spacecraft data multiplexing and transmission. The qualities of system performance that determine sounding capability are the dynamic range of data collection, the noise equivalent radiance of the system, the registration of the air columns sampled in each channel and the ability to upgrade the calibration of the instrument to maintain the performance standard throughout life. The basic features, operating characteristics and performance of the instrument in test are described. Early orbital information from the TIROS-N launched on October 13, 1978 is given and some observations on system quality are made.

  7. Design and development of wafer-level near-infrared micro-camera (United States)

    Zeller, John W.; Rouse, Caitlin; Efstathiadis, Harry; Haldar, Pradeep; Dhar, Nibir K.; Lewis, Jay S.; Wijewarnasuriya, Priyalal; Puri, Yash R.; Sood, Ashok K.


    SiGe offers a low-cost alternative to conventional infrared sensor material systems such as InGaAs, InSb, and HgCdTe for developing near-infrared (NIR) photodetector devices that do not require cooling and can offer high bandwidths and responsivities. As a result of the significant difference in thermal expansion coefficients between germanium and silicon, tensile strain incorporated into Ge epitaxial layers deposited on Si utilizing specialized growth processes can extend the operational range of detection to 1600 nm and longer wavelengths. We have fabricated SiGe based PIN detector devices on 300 mm diameter Si wafers in order to take advantage of high throughput, large-area complementary metal-oxide semiconductor (CMOS) technology. This device fabrication process involves low temperature epitaxial deposition of Ge to form a thin p+ seed/buffer layer, followed by higher temperature deposition of a thicker Ge intrinsic layer. An n+-Ge layer formed by ion implantation of phosphorus, passivating oxide cap, and then top copper contacts complete the PIN photodetector design. Various techniques including transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) have been employed to characterize the material and structural properties of the epitaxial growth and fabricated detector devices. In addition, electrical characterization was performed to compare the I-V dark current vs. photocurrent response as well as the time and wavelength varying photoresponse properties of the fabricated devices, results of which are likewise presented.

  8. Influence of skin blood flow and source-detector distance on near-infrared spectroscopy-determined cerebral oxygenation in humans

    DEFF Research Database (Denmark)

    Hirasawa, Ai; Yanagisawa, Shintaro; Tanaka, Naoki


    Most near-infrared spectroscopy (NIRS) apparatus fails to isolate cerebral oxygenation from an extracranial contribution although they use different source-detector distances. Nevertheless, the effect of different source-detector distances and change in extracranial blood flow on the NIRS signal...... in a semi-recumbent position, while extracranial blood flow was restricted by application of four different pressures (+20 to +80 mmHg) to the left temporal artery. The O2 Hb was measured at the forehead via a multidistance probe (source-detector distance; 15, 22·5 and 30 mm), and SkBF was determined...... by laser Doppler. Heart rate and blood pressure were unaffected by application of pressure to the temporal artery, while SkBF gradually decreased (Papplied pressure...

  9. Infrared thermography

    CERN Document Server

    Meola, Carosena


    This e-book conveys information about basic IRT theory, infrared detectors, signal digitalization and applications of infrared thermography in many fields such as medicine, foodstuff conservation, fluid-dynamics, architecture, anthropology, condition monitoring, non destructive testing and evaluation of materials and structures.

  10. Recent developments in materials and detectors for the infrared; Proceedings of the Meeting, Cannes, France, November 25, 26, 1985 (United States)

    Morten, F. D. (Editor); Seeley, John S. (Editor)


    The present conference on advancements in IR-sensitive materials and detector technologies employing them gives attention to thermal detectors, focal plane array processing detectors, novel detector designs, general properties of IR optics materials, and preparation methods for such materials. Specific topics encompass the fabrication of InSb MIS structures prepared by photochemical vapor deposition, IR heterodyne detectors employing cadmium mercury telluride, low microphony pyroelectric arrays, IR detection based on minority carrier extrusion, longwave reststrahl in IR crystals, and molecular beam techniques for optical thin film fabrication.

  11. Growth and characterization of In1-xGaxAs/InAs0.65Sb0.35 strained layer superlattice infrared detectors (United States)

    Ariyawansa, G.; Duran, J. M.; Reyner, C. J.; Steenbergen, E. H.; Yoon, N.; Wasserman, D.; Scheihing, J. E.


    Type-II strained layer superlattices (SLS) are an active research topic in the infrared detector community and applications for SLS detectors continue to grow. SLS detector technology has already reached the commercial market due to improvements in material quality, device design, and device fabrication. Despite this progress, the optimal superlattice design has not been established, and at various times has been believed to be InAs/GaSb, InAs/InGaSb, or InAs/InAsSb. Building on these, we investigate the properties of a new mid-wave infrared SLS material: InGaAs/InAsSb SLS. The ternary InGaAs/InAsSb SLS has three main advantages over other SLS designs: greater support for strain compensation, enhanced absorption due to increased electron-hole wavefunction overlap, and improved vertical hole mobility due to reduced hole effective mass. Here, we compare three ternary SLSs, with approximately the same bandgap (0.240 eV at 150 K), comprised of Ga fractions of 5%, 10%, and 20% to a reference sample with 0% Ga. Enhanced absorption is both theoretically predicted and experimentally realized. Furthermore, the characteristics of ternary SLS infrared detectors based on an nBn architecture are reported and exhibit nearly state-of-the-art dark current performance with minimal growth optimization. We report standard material and device characterization information, including dark current and external quantum efficiency, and provide further analysis that indicates improved quantum efficiency and vertical hole mobility. Finally, a 320×256 focal plane array built based on the In0.8Ga0.2As/InAs0.65Sb0.35 SLS design is demonstrated with promising performance.

  12. Technology for advanced focal plane arrays of HgCdTe and AIGaN

    CERN Document Server

    He, Li; Ni, Guoqiang


    This book introduces the basic framework of advanced focal plane technology based on the third-generation infrared focal plane concept. The essential concept, research advances, and future trends in advanced sensor arrays are comprehensively reviewed. Moreover, the book summarizes recent research advances in HgCdTe/AlGaN detectors for the infrared/ultraviolet waveband, with a particular focus on the numerical method of detector design, material epitaxial growth and processing, as well as Complementary Metal-Oxide-Semiconductor Transistor readout circuits. The book offers a unique resource for all graduate students and researchers interested in the technologies of focal plane arrays or electro-optical imaging sensors.

  13. Infrared Detector Research (United States)


    Bratt, Howard Davis, Frank Renda , Paul Chia, Arthur Lockwood. Bell Telephone Labs Leo F. Johnson, Alfred U. MacRae, Paul Norton. Texas Ins truments Werner...impurities which can "donate" their extra electron not required for bonding with the silicon atoms. When there are more acceptors than donors the material...will be p-type. The extra electrons from the donors can complete the bond missing due to the boron atoms. This process is call compensation. The

  14. HST/WFC3: new capabilities, improved IR detector calibrations, and long-term performance stability (United States)

    MacKenty, John W.; Baggett, Sylvia M.; Brammer, Gabriel; Hilbert, Bryan; Long, Knox S.; McCullough, Peter; Riess, Adam G.


    Wide Field Camera 3 (WFC3) is the most used instrument on board the Hubble Space Telescope. Providing a broad range of high quality imaging capabilities from 200 to 1700mn using Silicon CCD and HgCdTe IR detectors, WFC3 is fulfilling both our expectations and its formal requirements. With the re-establishment of the observatory level "spatial scan" capability, we have extended the scientific potential ofWFC3 in multiple directions. These controlled scans, often in combination with low resolution slit-less spectroscopy, enable extremely high precision differential photometric measurements of transiting exo-planets and direct measurement of sources considerably brighter than originally anticipated. In addition, long scans permit the measurement of the separation of star images to accuracies approaching 25 micro-arc seconds (a factor of 10 better than prior FGS or imaging measurements) enables direct parallax observations out to 4 kilo-parsecs. In addition, we have employed this spatial scan capability to both assess and improve the mid­ spatial frequency flat field calibrations. WFC3 uses a Teledyne HgCdTe 1014xl014 pixel Hawaii-lR infrared detector array developed for this mission. One aspect of this detector with implications for many types of science observations is the localized trapping of charge. This manifests itself as both image persistence lasting several hours and as an apparent response variation with photon arrival rate over a large dynamic range. Beyond a generally adopted observing strategy of obtaining multiple observations with small spatial offsets, we have developed a multi-parameter model that accounts for source flux, accumulated signal level, and decay time to predict image persistence at the pixel level. Using a running window through the entirety of the acquired data, we now provide observers with predictions for each individual exposure within several days of its acquisition. Ongoing characterization of the sources on infrared background and

  15. Massless Dirac fermions in semimetal HgCdTe (United States)

    Marchewka, M.; Grendysa, J.; Żak, D.; Tomaka, G.; Śliż, P.; Sheregii, E. M.


    Magneto-transport results obtained for the strained 100 nm thick Hg1-x CdxTe (x=0.135) layer grown by MBE on the CdTe/GaAs substrate are interpreted by the 8×8 kp model with the in-plane tensile strain. The dispersion relation for the investigated structure proves that the Dirac point is located in the gap caused by the strain. It is also shown that the fan of the Landau Levels (LL's) energy calculated for topological protected surface states for the studied HgCdTe alloy corresponds to the fan of the LL's calculated using the graphen-like Hamiltonian which gives excellent agreement with the experimental data for velocity on the Fermi level equal to vf ≈ 0.85×106 m/s. That characterized strained Hg1-x CdxTe layers (0.13 < x < 0.14) are a perfect Topological Insulator with good perspectives of further applications.

  16. Development activities on NIR large format MCT detectors for astrophysics and space science at CEA and SOFRADIR (United States)

    Boulade, Olivier; Moreau, Vincent; Mulet, Patrick; Gravrand, Olivier; Cervera, Cyril; Zanatta, Jean-Paul; Castelein, Pierre; Guellec, Fabrice; Fièque, Bruno; Chorier, Philippe; Roumegoux, Julien


    CEA and SOFRADIR have been manufacturing and characterizing near infrared detectors in the frame of ESA's near infrared large format sensor array roadmap to develop a 2Kx2K large format low flux low noise device for space applications such as astrophysics. These detectors use HgCdTe as the absorbing material and p/n diode technology. The technological developments (photovoltaic technology, readout circuit, ...) are shared between CEA/LETI and SOFRADIR, both in Grenoble, while most of the performances are evaluated at CEA/IRFU in Saclay where a dedicated test facility has been developed, in particular to measure very low dark currents. The paper will present the current status of these developments at the end of ESA's NIRLFSA phase 2. The performances of the latest batch of devices meet or are very close to all the requirements (quantum efficiency, dark current, cross talk, readout noise, ...) even though a glow induced by the ROIC prevents the accurate measurement of the dark current. The current devices are fairly small, 640x512 15μm pixels, and the next phase of activity will target the development of a full size 2Kx2K detector. From the design and development, to the manufacturing and finally the testing, that type of detector requests a high level of mastering. An appropriate manufacturing and process chain compatible with such a size is needed at industrial level and results obtained with CEA technology coupled with Sofradir industrial experience and work on large dimension detector allow French actors to be confident to address this type of future missions.

  17. The Infrared Camera for RATIR, a Rapid Response GRB Followup Instrument (United States)

    Rapchun, David A.; Alardin, W.; Bigelow, B. C.; Bloom, J.; Butler, N.; Farah, A.; Fox, O. D.; Gehrels, N.; Gonzalez, J.; Klein, C.; Kutyrev, A. S.; Lotkin, G.; Morisset, C.; Moseley, S. H.; Richer, M.; Robinson, F. D.; Samuel, M. V.; Sparr, L. M.; Tucker, C.; Watson, A.


    RATIR (Reionization and Transients Infrared instrument) will be a hybrid optical/near IR imager that will utilize the "J-band dropout" to rapidly identify very high redshift (VHR) gamma-ray bursts (GRBs) from a sample of all observable Swift bursts. Our group at GSFC is developing the instrument in collaboration with UC Berkeley (UCB) and University of Mexico (UNAM). RATIR has both a visible and IR camera, which give it access to 8 bands spanning visible and IR wavelengths. The instrument implements a combination of filters and dichroics to provide the capability of performing photometry in 4 bands simultaneously. The GSFC group leads the design and construction of the instrument's IR camera, equipped with two HgCdTe 2k x 2k Teledyne detectors. The cryostat housing these detectors is cooled by a mechanical cryo-compressor, which allows uninterrupted operation on the telescope. The host 1.5-m telescope, located at the UNAM San Pedro Martir Observatory, Mexico, has recently undergone robotization, allowing for fully automated, continuous operation. After commissioning in the spring of 2011, RATIR will dedicate its time to obtaining prompt follow-up observations of GRBs and identifying VHR GRBs, thereby providing a valuable tool for studying the epoch of reionization.

  18. Test and evaluation of infrared detectors and arrays; Proceedings of the Meeting, Orlando, FL, Mar. 27-29, 1989 (United States)

    Hoke, Forney M.

    Papers on the testing and evaluation of IR detectors and arrays are presented, covering topics such as a short wavelength IR test system, pulse height analysis, the use of an expert system for IR detector testing, low-background IR focal plane testing, electron beam testing, high performance silicide Schottky photodiodes, the SDI organization focal plane test program, the absorption cross section of arsenic in silicon, and long wavelength IR hybrids. Other topics include low background radiometric detector measurements, an ultralow background dewar for IR detector characterization studies, a computer assisted mosaic array test station, a configurable detector array test station, automated detector material characterization capabilities, and a test system for mercury cadmium telluride photoconductor arrays. Additional topics include ionization dosimetry measurements inside a dewar for linac electron and californium-252 neutron environments, a radiation test facility using a variable-flux electron beam source, automated visual inspection of IR focal plane arrays, a titanium cryostat for low temperature radiation effects studies, a low dose rate gamma test facility, and the test and evaluation of stability in IR staring focal plane arrays after nonuniformity correction.

  19. Characterization and Performance of the Cananea Near-infrared Camera (CANICA) (United States)

    Devaraj, R.; Mayya, Y. D.; Carrasco, L.; Luna, A.


    We present details of characterization and imaging performance of the Cananea Near-infrared Camera (CANICA) at the 2.1 m telescope of the Guillermo Haro Astrophysical Observatory (OAGH) located in Cananea, Sonora, México. CANICA has a HAWAII array with a HgCdTe detector of 1024 × 1024 pixels covering a field of view of 5.5 × 5.5 arcmin2 with a plate scale of 0.32 arcsec/pixel. The camera characterization involved measuring key detector parameters: conversion gain, dark current, readout noise, and linearity. The pixels in the detector have a full-well-depth of 100,000 e‑ with the conversion gain measured to be 5.8 e‑/ADU. The time-dependent dark current was estimated to be 1.2 e‑/sec. Readout noise for correlated double sampled (CDS) technique was measured to be 30 e‑/pixel. The detector shows 10% non-linearity close to the full-well-depth. The non-linearity was corrected within 1% levels for the CDS images. Full-field imaging performance was evaluated by measuring the point spread function, zeropoints, throughput, and limiting magnitude. The average zeropoint value in each filter are J = 20.52, H = 20.63, and K = 20.23. The saturation limit of the detector is about sixth magnitude in all the primary broadbands. CANICA on the 2.1 m OAGH telescope reaches background-limited magnitudes of J = 18.5, H = 17.6, and K = 16.0 for a signal-to-noise ratio of 10 with an integration time of 900 s.

  20. Growth features of HgCdTe LPE layers

    International Nuclear Information System (INIS)

    Huseynov, E.K.; Eminov, Sh.O.; Ibragimov, T.I.; Ismaylov, N.J.; Rajabli, A.A.


    Full text : The results of growth of Hg 1 -xCd x Te (MCT) layers by liquid phase epitaxy (LPE) from Te-rich solutions (molar fraction (Hg 1 -zCd z )(1.y)Te y , z=0.054, y=0.805 for TL=501 degrees Celsium) obtained by the tipping method in closed system is presented. Epitaxial layers with different compositions (x=0.20-0.22) and thicknesses (10-20 μm) suitable for manufacturing the photodiode structures operable at 8-14 μm spectrum range were grown on B oriented Cd 0 .96Zn 0 ,04Te polished and repolished substrates. The growth was carried out in the temperature range 500-480 degrees Celsium with cooling rates 0.05-0.1 degrees Celsium/min in a sealed quartz ampoule using the original apparatus for LPE. The attention was paid mainly to the surface morphological quality, good decantation from the layers, uniformity of composition and thickness of films. One of the limitations of the most LPE growth apparatus (cassettes) with slider or tipping system is their impossibility to wipe the last drop of growth solution from the surface of just-grown epilayer. Some remnant or residual of the growth solution tends to adhere to the surface of the epilayer after growth in such apparatus and strongly affect the surface quality. The novel apparatus for LPE providing the surface without unwanted residual drops of melt solution of Hg, Cd and Te was developed with the aim of solving such a problem. The effect of different steps of LPE growth on morphology and composition of epitaxial layers was studied. By holding the CdZnTe substrate inside the growth ampoule at the melt homogenization temperature during of 15-50 min without contact with the melt resulted in visually (using the Leitzorthoplan microscopes x 500-1000) observed surface roughness. Using the expressions for the Te-angle of Hg-Cd-Te phase diagram the effect of the preliminary synthesis of the source on liquidus temperature and composition of the epilayers was numerically evaluated. HgCdTe layers were characterized using

  1. Photon-Counting Kinetic Inductance Detectors (KID) for Far/Mid-Infrared Space Spectroscopy with the Origins Space Telescope (OST) (United States)

    Noroozian, Omid; Barrentine, Emily M.; Stevenson, Thomas R.; Brown, Ari D.; Moseley, Samuel Harvey; Wollack, Edward; Pontoppidan, Klaus Martin; U-Yen, Konpop; Mikula, Vilem


    Photon-counting detectors are highly desirable for reaching the ~ 10-20 W/√Hz power sensitivity permitted by the Origins Space Telescope (OST). We are developing unique Kinetic Inductance Detectors (KIDs) with photon counting capability in the far/mid-IR. Combined with an on-chip far-IR spectrometer onboard OST these detectors will enable a new data set for exploring galaxy evolution and the growth of structure in the Universe. Mid-IR spectroscopic surveys using these detectors will enable mapping the composition of key volatiles in planet-forming material around protoplanetary disks and their evolution into solar systems. While these OST science objectives represent a well-organized community agreement they are impossible to reach without a significant leap forward in detector technology, and the OST is likely not to be recommended if a path to suitable detectors does not exist.To reach the required sensitivity we are experimenting with superconducting resonators made from thin aluminum films on single-crystal silicon substrates. Under the right conditions, small-volume inductors made from these films can become ultra-sensitive to single photons >90 GHz. Understanding the physics of these superconductor-dielectric systems is critical to performance. We achieved a very high quality factor of 0.5 x 106 for a 10-nm Al resonator at n ~ 1 microwave photon drive power, by far the highest value for such thin films in the literature. We measured a residual electron density of detector when illuminated with randomly arriving photon events. Our results show that photon counting with >95% efficiency at 0.5 - 1.0 THz is achievable.We report on these developments and discuss plans to test in our facility through funding from our recently awarded ROSES-APRA grant and Roman Technology Fellowship award.

  2. Microstructure, electrical, and optical properties of evaporated PtSi/p-Si(100) Schottky barriers as high quantum efficient infrared detectors

    International Nuclear Information System (INIS)

    Wu Jihhuah; Chang Rongsen; Horng Gwoji


    The effects of the microstructure and the electrical and optical properties on the formation at highly efficient infrared PtSi Schottky barrier detectors (SBD) have been studied in detail. Two- to twelve-nanometer-thick PtSi films were grown by evaporation at temperature ranging from 350 to 550 deg. C. The electron diffraction patterns indicate the existence of both the (11-bar0) and (12-bar1) orientations when PtSi films formed at 350 deg. C. However, the diffraction patterns show only the (12-bar1) orientation when the PtSi films are formed at 450 deg. C or above. The electrical barrier height of the Schottky barrier detector that formed at 350 deg. C was about 20 meV higher than that formed at 450 deg. C or above. The grain size and the film thickness had a negligible effect on the electrical barrier height. However, the optical performance was strongly dependent on the film thickness and the growth conditions. The 350 deg. C PtSi film showed increased quantum efficiency as the film thickness decreased. The optimal thickness that provided the highest responsivity was 2 nm. On the other hand, the optimal thickness shifted to 8 nm for PtSi film formed at 450 deg. C or above. These results indicate that the quantum efficiency of a detector can be improved if the PtSi film has an orientation at (12-bar1), a larger grain size, and an optimal film thickness

  3. Thermal Cycle Annealing and its Application to Arsenic-Ion Implanted HgCdTe (United States)


    Rao Mulpuri Sina Simingalam, Priyalal Wijewarnasuriya, Mulpuri V. Rao 1720BH c. THIS PAGE The public reporting burden for this collection of...Implanted HgCdTe Sina Simingalama,b,c, Priyalal Wijewarnasuriyab, Mulpuri V. Raoc a. School of Physics, Astronomy and Computational Sciences, George

  4. Arsenic complexes optical signatures in As-doped HgCdTe

    Energy Technology Data Exchange (ETDEWEB)

    Gemain, F.; Robin, I. C.; Brochen, S.; Ballet, P.; Gravrand, O.; Feuillet, G. [CEA-LETI Minatec Campus, 17 rue des Martyrs, 38000 Grenoble (France)


    In this paper, the optical signatures of arsenic complexes in As-doped HgCdTe samples grown by molecular beam epitaxy are clearly identified using comparison between photoluminescence spectra, Extended X-Ray Absorption Fine Structure, and Hall measurements. The ionization energies of the different complexes are measured both by photoluminescence and Hall measurements.

  5. A method to eliminate wetting during the homogenization of HgCdTe (United States)

    Su, Ching-Hua; Lehoczky, S. L.; Szofran, F. R.


    Adhesion of HgCdTe samples to fused silica ampoule walls, or 'wetting', during the homogenization process was eliminated by adopting a slower heating rate. The idea is to decrease Cd activity in the sample so as to reduce the rate of reaction between Cd and the silica wall.

  6. Arsenic complexes optical signatures in As-doped HgCdTe

    International Nuclear Information System (INIS)

    Gemain, F.; Robin, I. C.; Brochen, S.; Ballet, P.; Gravrand, O.; Feuillet, G.


    In this paper, the optical signatures of arsenic complexes in As-doped HgCdTe samples grown by molecular beam epitaxy are clearly identified using comparison between photoluminescence spectra, Extended X-Ray Absorption Fine Structure, and Hall measurements. The ionization energies of the different complexes are measured both by photoluminescence and Hall measurements.

  7. Structural and electrical properties of InAs/GaSb superlattices grown by metalorganic vapor phase epitaxy for midwavelength infrared detectors

    Energy Technology Data Exchange (ETDEWEB)

    Arikata, Suguru; Kyono, Takashi [Semiconductor Technologies Laboratory, Sumitomo Electric Industries, LTD., Hyogo (Japan); Miura, Kouhei; Balasekaran, Sundararajan; Inada, Hiroshi; Iguchi, Yasuhiro [Transmission Devices Laboratory, Sumitomo Electric Industries, LTD., Yokohama (Japan); Sakai, Michito [Sensor System Research Group, Japan Aerospace Exploration Agency (JAXA), Tsukuba, Ibaraki (Japan); Katayama, Haruyoshi [Space Technology Directorate I, Japan Aerospace Exploration Agency (JAXA), Tsukuba, Ibaraki (Japan); Kimata, Masafumi [College of Science and Engineering, Ritsumeikan University, Shiga (Japan); Akita, Katsushi [Sumiden Semiconductor Materials, LTD., Hyogo (Japan)


    InAs/GaSb superlattice (SL) structures were fabricated on GaSb substrates by metalorganic vapor phase epitaxy (MOVPE) toward midwavelength infrared (MWIR) photodiodes. Almost defect-free 200-period SLs with a strain-compensation interfacial layer were successfully fabricated and demonstrate an intense photoluminescence peak centered at 6.1 μm at 4 K and an external quantum efficiency of 31% at 3.5 μm at 20 K. These results indicate that the high-performance MWIR detectors can be fabricated in application with the InAs/GaSb SLs grown by MOVPE as an attractive method for production. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Fabrication of an Absorber-Coupled MKID Detector and Readout for Sub-Millimeter and Far-Infrared Astronomy (United States)

    Brown, Ari-David; Hsieh, Wen-Ting; Moseley, S. Harvey; Stevenson, Thomas R.; U-yen, Kongpop; Wollack, Edward J.


    We have fabricated absorber-coupled microwave kinetic inductance detector (MKID) arrays for sub-millimeter and farinfrared astronomy. Each detector array is comprised of lambda/2 stepped impedance resonators, a 1.5µm thick silicon membrane, and 380µm thick silicon walls. The resonators consist of parallel plate aluminum transmission lines coupled to low impedance Nb microstrip traces of variable length, which set the resonant frequency of each resonator. This allows for multiplexed microwave readout and, consequently, good spatial discrimination between pixels in the array. The Al transmission lines simultaneously act to absorb optical power and are designed to have a surface impedance and filling fraction so as to match the impedance of free space. Our novel fabrication techniques demonstrate high fabrication yield of MKID arrays on large single crystal membranes and sub-micron front-to-back alignment of the microstrip circuit.

  9. Automatic internal crack detection from a sequence of infrared images with a triple-threshold Canny edge detector (United States)

    Wang, Gaochao; Tse, Peter W.; Yuan, Maodan


    Visual inspection and assessment of the condition of metal structures are essential for safety. Pulse thermography produces visible infrared images, which have been widely applied to detect and characterize defects in structures and materials. When active thermography, a non-destructive testing tool, is applied, the necessity of considerable manual checking can be avoided. However, detecting an internal crack with active thermography remains difficult, since it is usually invisible in the collected sequence of infrared images, which makes the automatic detection of internal cracks even harder. In addition, the detection of an internal crack can be hindered by a complicated inspection environment. With the purpose of putting forward a robust and automatic visual inspection method, a computer vision-based thresholding method is proposed. In this paper, the image signals are a sequence of infrared images collected from the experimental setup with a thermal camera and two flash lamps as stimulus. The contrast of pixels in each frame is enhanced by the Canny operator and then reconstructed by a triple-threshold system. Two features, mean value in the time domain and maximal amplitude in the frequency domain, are extracted from the reconstructed signal to help distinguish the crack pixels from others. Finally, a binary image indicating the location of the internal crack is generated by a K-means clustering method. The proposed procedure has been applied to an iron pipe, which contains two internal cracks and surface abrasion. Some improvements have been made for the computer vision-based automatic crack detection methods. In the future, the proposed method can be applied to realize the automatic detection of internal cracks from many infrared images for the industry.

  10. Thermal stability of atomic layer deposition Al2O3 film on HgCdTe (United States)

    Zhang, P.; Sun, C. H.; Zhang, Y.; Chen, X.; He, K.; Chen, Y. Y.; Ye, Z. H.


    Thermal stability of Atomic Layer Deposition Al2O3 film on HgCdTe was investigated by Al2O3 film post-deposition annealing treatment and Metal-Insulator-Semiconductor device low-temperature baking treatment. The effectiveness of Al2O3 film was evaluated by measuring the minority carrier lifetime and capacitance versus voltage characteristics. After annealing treatment, the minority carrier lifetime of the HgCdTe sample presented a slight decrease. Furthermore, the fixed charge density and the slow charge density decreased significantly in the annealed MIS device. After baking treatment, the fixed charge density and the slow charge density of the unannealed and annealed MIS devices decreased and increased, respectively.

  11. Linear Mode HgCdTe Avalanche Photodiodes for Photon Counting Applications (United States)

    Sullivan, William, III; Beck, Jeffrey; Scritchfield, Richard; Skokan, Mark; Mitra, Pradip; Sun, Xiaoli; Abshire, James; Carpenter, Darren; Lane, Barry


    An overview of recent improvements in the understanding and maturity of linear mode photon counting with HgCdTe electron-initiated avalanche photodiodes is presented. The first HgCdTe LMPC 2x8 format array fabricated in 2011 with 64 micron pitch was a remarkable success in terms of demonstrating a high single photon signal to noise ratio of 13.7 with an excess noise factor of 1.3-1.4, a 7 ns minimum time between events, and a broad spectral response extending from 0.4 micron to 4.2 micron. The main limitations were a greater than 10x higher false event rate than expected of greater than 1 MHz, a 5-7x lower than expected APD gain, and a photon detection efficiency of only 50% when greater than 60% was expected. This paper discusses the reasons behind these limitations and the implementation of their mitigations with new results.

  12. Continuous-wave near-photon counting spectral imaging detector in the mid-infrared by upconversion

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Tidemand-Lichtenberg, Peter; Pedersen, Christian


    is usually measured in number of electrons. The second noise source is usually referred to as dark noise, which is the background signal generated over time. Dark noise is usually measured in electrons per pixel per second. For silicon cameras certain models like EM-CCD have close to zero read noise, whereas...... high-end IR cameras have read noise of hundreds of electrons. The dark noise for infrared cameras based on semiconductor materials is also substantially higher than for silicon cameras, typical values being millions of electrons per pixel per second for cryogenically cooled cameras whereas peltier...... cooled CCD cameras have dark noise measured in fractions of electrons per pixel per second. An ideal solution thus suggest the combination of an efficient low noise image wavelength conversion system combined with low noise silicon based cameras for low noise imaging in the IR region. We discuss image...

  13. Effects of epitaxial structure and processing on electrical characteristics of InAs-based nBn infrared detectors (United States)

    Du, X.; Savich, G. R.; Marozas, B. T.; Wicks, G. W.


    The conventional processing of the III-V nBn photodetectors defines mesa devices by etching the contact n-layer and stopping immediately above the barrier, i.e., a shallow etch. This processing enables great suppression of surface leakage currents without having to explore surface passivation techniques. However, devices that are made with this processing scheme are subject to lateral diffusion currents. To address the lateral diffusion current, we compare the effects of different processing approaches and epitaxial structures of nBn detectors. The conventional solution for eliminating lateral diffusion current, a deep etch through the barrier and the absorber, creates increased dark currents and an increased device failure rate. To avoid deep etch processing, a new device structure is proposed, the inverted-nBn structure. By comparing with the conventional nBn structure, the results show that the lateral diffusion current is effectively eliminated in the inverted-nBn structure without elevating the dark currents.

  14. Surface passivation of HgCdTe by CdZnTe and its characteristics (United States)

    Lee, T. S.; Choi, K. K.; Jeoung, Y. T.; Kim, H. K.; Kim, J. M.; Kim, Y. H.; Chang, J. M.; Song, W. S.; Kim, S. U.; Park, M. J.; Lee, S. D.


    In this paper, we report the results of capacitance-voltage measurements conducted on several metal-insulator semiconductor (MIS) capacitors in which HgCdTe surfaces are treated with various surface etching and oxidation processes. CdZnTe passivation layers were deposited on HgCdTe surfaces by thermal evaporation after the surfaces were etched with 0.5-2.0% bromine in methanol solution, or thin oxide layers (tox ˜ few ten Å) were grown on the surfaces, in order to investigate effects of the surface treatments on the electrical properties of the surfaces, as determined from capacitance-voltage (C-V) measurements at 80K and 1 MHz. A negative flat band voltage has been observed for MIS capacitors fabricated after etching of HgCdTe surfaces with bromine in methanol solutions, which is reported to make the surface Te-rich. It is inferred that residual Te on the surface is a positive charge, Te4+. C-V characteristics for MIS capacitors fabricated on oxide surfaces grown by air-exposure and electrolytic process have shown large hysteresis effects, from which it is inferred that imperfect and electrically active oxide compounds and HgTe particles near the surface become slow interface states.

  15. Single Photon Sensitive HgCdTe Avalanche Photodiode Detector (APD), Phase II (United States)

    National Aeronautics and Space Administration — Leveraging Phase I SBIR successes, in Phase II, a single photon sensitive LIDAR receiver will be fabricated and delivered to NASA. In Phase I, high-gain,...

  16. Characterization of GaSb/InAs type II infrared detectors at very long wavelengths: carrier scattering at defect clusters (United States)

    Kitchin, M. R.; Jaros, M.


    We report a systematic study into carrier scattering by isovalent defects within GaSb/InAs superlattices. The heterostructure system which we investigate has attracted recent interest as the active region of a photodetector for very long wavelength infrared (VLWIR) (⩾12 μm) radiation. To achieve our objective, we employed models of the electronic band structure and scattering cross-section. We considered isolated, substitutional defects at each atom site throughout the unit cell in turn and found that the scattering magnitude generally follows the carrier envelope function, being greatest where the overlap of charge with the defect is highest. We scrutinized the contribution of lattice relaxation around defects to the overall scattering, by comparing calculations where this effect was, in turn, included and excluded. We identified some anomalous contributions of relaxation to both qualitative and quantitative features of the cross-section. Physical mechanisms to explain these effects must be arrived at in order to attain satisfactory characterization of these materials, highlighting the need for both microscopic models and further research. Additional modelling of islands of such defects indicated that the cross-section is proportional to the square of the number of constituent atoms, for both carrier types (holes and electrons) and each defect type. This article demonstrates important links between key growth issues and the dynamical properties of these novel semiconductor devices.

  17. Numerical method to optimize the polar-azimuthal orientation of infrared superconducting-nanowire single-photon detectors. (United States)

    Csete, Mária; Sipos, Áron; Najafi, Faraz; Hu, Xiaolong; Berggren, Karl K


    A finite-element method for calculating the illumination-dependence of absorption in three-dimensional nanostructures is presented based on the radio frequency module of the Comsol Multiphysics software package (Comsol AB). This method is capable of numerically determining the optical response and near-field distribution of subwavelength periodic structures as a function of illumination orientations specified by polar angle, φ, and azimuthal angle, γ. The method was applied to determine the illumination-angle-dependent absorptance in cavity-based superconducting-nanowire single-photon detector (SNSPD) designs. Niobium-nitride stripes based on dimensions of conventional SNSPDs and integrated with ~ quarter-wavelength hydrogen-silsesquioxane-filled nano-optical cavity and covered by a thin gold film acting as a reflector were illuminated from below by p-polarized light in this study. The numerical results were compared to results from complementary transfer-matrix-method calculations on composite layers made of analogous film-stacks. This comparison helped to uncover the optical phenomena contributing to the appearance of extrema in the optical response. This paper presents an approach to optimizing the absorptance of different sensing and detecting devices via simultaneous numerical optimization of the polar and azimuthal illumination angles. © 2011 Optical Society of America

  18. Charge Gain, Voltage Gain, and Node Capacitance of the SAPHIRA Detector Pixel by Pixel (United States)

    Pastrana, Izabella M.; Hall, Donald N. B.; Baker, Ian M.; Jacobson, Shane M.; Goebel, Sean B.


    The University of Hawai`i Institute for Astronomy has partnered with Leonardo (formerly Selex) in the development of HgCdTe linear mode avalanche photodiode (L-APD) SAPHIRA detectors. The SAPHIRA (Selex Avalanche Photodiode High-speed Infra-Red Array) is ideally suited for photon-starved astronomical observations, particularly near infrared (NIR) adaptive optics (AO) wave-front sensing. I have measured the stability, and linearity with current, of a 1.7-um (10% spectral bandpass) infrared light emitting diode (IR LED) used to illuminate the SAPHIRA and have then utilized this source to determine the charge gain (in e-/ADU), voltage gain (in uV/ADU), and node capacitance (in fF) for each pixel of the 320x256@24um SAPHIRA. These have previously only been averages over some sub-array. Determined from the ratio of the temporal averaged signal level to variance under constant 1.7-um LED illumination, I present the charge gain pixel-by-pixel in a 64x64 sub-array at the center of the active area of the SAPHIRA (analyzed separately as four 32x32 sub-arrays) to be about 1.6 e-/ADU (σ=0.5 e-/ADU). Additionally, the standard technique of varying the pixel reset voltage (PRV) in 10 mV increments and recording output frames for the same 64x64 subarray found the voltage gain per pixel to be about 11.7 uV/ADU (σ=0.2 uV/ADU). Finally, node capacitance was found to be approximately 23 fF (σ=6 fF) utilizing the aforementioned charge and voltage gain measurements. I further discuss the linearity measurements of the 1.7-um LED used in the charge gain characterization procedure.

  19. Numerical simulation of the modulation transfer function (MTF) in infrared focal plane arrays: simulation methodology and MTF optimization (United States)

    Schuster, J.


    Military requirements demand both single and dual-color infrared (IR) imaging systems with both high resolution and sharp contrast. To quantify the performance of these imaging systems, a key measure of performance, the modulation transfer function (MTF), describes how well an optical system reproduces an objects contrast in the image plane at different spatial frequencies. At the center of an IR imaging system is the focal plane array (FPA). IR FPAs are hybrid structures consisting of a semiconductor detector pixel array, typically fabricated from HgCdTe, InGaAs or III-V superlattice materials, hybridized with heat/pressure to a silicon read-out integrated circuit (ROIC) with indium bumps on each pixel providing the mechanical and electrical connection. Due to the growing sophistication of the pixel arrays in these FPAs, sophisticated modeling techniques are required to predict, understand, and benchmark the pixel array MTF that contributes to the total imaging system MTF. To model the pixel array MTF, computationally exhaustive 2D and 3D numerical simulation approaches are required to correctly account for complex architectures and effects such as lateral diffusion from the pixel corners. It is paramount to accurately model the lateral di_usion (pixel crosstalk) as it can become the dominant mechanism limiting the detector MTF if not properly mitigated. Once the detector MTF has been simulated, it is directly decomposed into its constituent contributions to reveal exactly what is limiting the total detector MTF, providing a path for optimization. An overview of the MTF will be given and the simulation approach will be discussed in detail, along with how different simulation parameters effect the MTF calculation. Finally, MTF optimization strategies (crosstalk mitigation) will be discussed.

  20. Low background infrared (LBIR) facility (United States)

    Federal Laboratory Consortium — The Low background infrared (LBIR) facility was originally designed to calibrate user supplied blackbody sources and to characterize low-background IR detectors and...

  1. Development and characterisation of MCT detectors for space astrophysics at CEA (United States)

    Boulade, O.; Baier, N.; Castelein, P.; Cervera, C.; Chorier, P.; Destefanis, G.; Fièque, B.; Gravrand, O.; Guellec, F.; Moreau, V.; Mulet, P.; Pinsard, F.; Zanatta, J.-P.


    The Laboratoire Electronique et Traitement de l'Information (LETI) of the Commissariat à l'Energie Atomique (CEA, Grenoble, France) has been involved in the development of infrared detectors based on HgCdTe (MCT) material for over 30 years, mainly for defence and security programs [1]. Once the building blocks are developed at LETI (MCT material process, diode technology, hybridization, …), the industrialization is performed at SOFRADIR (also in Grenoble, France) which also has its own R&D program [2]. In past years, LETI also developed infrared detectors for space astrophysics in the mid infrared range - the long wave detector of the ISOCAM camera onboard ISO - as well as in the far infrared range - the bolometer arrays of the Herschel/PACS photometer unit -, both instruments which were under the responsibility of the Astrophysics department of CEA (IRFU/SAp, Saclay, France). Nowadays, the infrared detectors used in space and ground based astronomical instruments all come from vendors in the US. For programmatic reasons - increase the number of available vendors, decrease the cost, mitigate possible export regulations, …- as well as political ones - spend european money in Europe -, the European Space Agency (ESA) defined two roadmaps (one in the NIR-SWIR range, one in the MWIR-LWIR range) that will eventually allow for the procurement of infrared detectors for space astrophysics within Europe. The French Space Agency (CNES) also started the same sort of roadmaps, as part of its contribution to the different space missions which involve delivery of instruments by French laboratories. It is important to note that some of the developments foreseen in these roadmaps also apply to Earth Observations. One of the main goal of the ESA and CNES roadmaps is to reduce the level of dark current in MCT devices at all wavelengths. The objective is to use the detectors at the highest temperature where the noise induced by the dark current stays compatible with the photon

  2. Attenuated total internal reflection infrared microspectroscopic imaging using a large-radius germanium internal reflection element and a linear array detector. (United States)

    Patterson, Brian M; Havrilla, George J


    The number of techniques and instruments available for Fourier transform infrared (FT-IR) microspectroscopic imaging has grown significantly over the past few years. Attenuated total internal reflectance (ATR) FT-IR microspectroscopy reduces sample preparation time and has simplified the analysis of many difficult samples. FT-IR imaging has become a powerful analytical tool using either a focal plane array or a linear array detector, especially when coupled with a chemometric analysis package. The field of view of the ATR-IR microspectroscopic imaging area can be greatly increased from 300 x 300 microm to 2500 x 2500 microm using a larger internal reflection element of 12.5 mm radius instead of the typical 1.5 mm radius. This gives an area increase of 70x before aberrant effects become too great. Parameters evaluated include the change in penetration depth as a function of beam displacement, measurements of the active area, magnification factor, and change in spatial resolution over the imaging area. Drawbacks such as large file size will also be discussed. This technique has been successfully applied to the FT-IR imaging of polydimethylsiloxane foam cross-sections, latent human fingerprints, and a model inorganic mixture, which demonstrates the usefulness of the method for pharmaceuticals.

  3. MSM-Metal Semiconductor Metal Photo-detector Using Black Silicon Germanium (SiGe) for Extended Wavelength Near Infrared Detection (United States)


    its effect on the optical beam. Computer Tunable optical source Detectors Test MSM detector Lock-in- amplifier Multiplexer Transimpedance ... amplifier Three-way beam splitter L3 sample L1 Light source L4 L2 Reference Detector Reflectance Detector

  4. High Temperature Superconductor Resonator Detectors (United States)

    National Aeronautics and Space Administration — High Temperature Superconductor (HTS) infrared detectors were studied for years but never matured sufficiently for infusion into instruments. Several recent...

  5. La détection infrarouge avec les plans focaux non refroidis : état de l'artUncooled focal plane infrared detectors: the state of the art (United States)

    Tissot, Jean-Luc


    The emergence of uncooled detectors has opened new opportunities for IR detection for both military and commercial applications. Development of such devices involves a lot of trade-offs between the different parameters that define the technological stack. These trade-offs explain the number of different architectures that are under worldwide development. The key factor is to find a high sensitivity and low noise thermometer material compatible with silicon technology in order to achieve high thermal isolation in the smallest area as possible. Ferroelectric thermometer based hybrid technology and electrical resistive thermometer based (microbolometer) technology are under development. LETI and ULIS have chosen from the very beginning to develop first a monolithic microbolometer technology fully compatible with commercially available CMOS technology and secondly amorphous silicon based thermometer. This silicon approach has the greatest potential for reducing infrared detector manufacturing cost. After the development of the technology, the transfer to industrial facilities has been performed in a short period of time and the production is now ramping up with ULIS team in new facilities. LETI and ULIS are now working to facilitate the IRFPA integration into equipment in order to address a very large market. Achievement of this goal needs the development of smart sensors with on-chip advanced functions and the decrease of manufacturing cost of IRFPA by decreasing the pixel pitch and simplifying the vacuum package. We present in this paper the technology developed by CEA/LETI and its improvement for being able to designs 384×288 and 160×120 arrays with a pitch of 35 μm. Thermographic application needs high stability infrared detector with a precise determination of the amount of absorbed infrared flux. Hence, infrared detector with internal temperature stabilized shield has been developed and characterized. These results will be presented. To cite this article: J

  6. Comparison of Measured Dark Current Distributions with Calculated Damage Energy Distributions in HgCdTe (United States)

    Marshall, C. J.; Marshall, P. W.; Howe, C. L.; Reed, R. A.; Weller, R. A.; Mendenhall, M.; Waczynski, A.; Ladbury, R.; Jordan, T. M.


    This paper presents a combined Monte Carlo and analytic approach to the calculation of the pixel-to-pixel distribution of proton-induced damage in a HgCdTe sensor array and compares the results to measured dark current distributions after damage by 63 MeV protons. The moments of the Coulombic, nuclear elastic and nuclear inelastic damage distributions were extracted from Monte Carlo simulations and combined to form a damage distribution using the analytic techniques first described in [1]. The calculations show that the high energy recoils from the nuclear inelastic reactions (calculated using the Monte Carlo code MCNPX [2]) produce a pronounced skewing of the damage energy distribution. While the nuclear elastic component (also calculated using the MCNPX) contributes only a small fraction of the total nonionizing damage energy, its inclusion in the shape of the damage across the array is significant. The Coulombic contribution was calculated using MRED [3-5], a Geant4 [4,6] application. The comparison with the dark current distribution strongly suggests that mechanisms which are not linearly correlated with nonionizing damage produced according to collision kinematics are responsible for the observed dark current increases. This has important implications for the process of predicting the on-orbit dark current response of the HgCdTe sensor array.

  7. Recent advances in infrared astronomy

    International Nuclear Information System (INIS)

    Robson, E.I.


    A background survey is given of developments in infrared astronomy during the last decade. Advantages obtained in using infrared wavelengths to penetrate the Earth's atmosphere and the detectors used for this work are considered. Infrared studies of, among other subjects, the stars, dust clouds, the centre of our galaxy and the 3k cosmic background radiation, are discussed. (UK)

  8. A polychromator-type near-infrared spectrometer with a high-sensitivity and high-resolution photodiode array detector for pharmaceutical process monitoring on the millisecond time scale. (United States)

    Murayama, Kodai; Genkawa, Takuma; Ishikawa, Daitaro; Komiyama, Makoto; Ozaki, Yukihiro


    In the fine chemicals industry, particularly in the pharmaceutical industry, advanced sensing technologies have recently begun being incorporated into the process line in order to improve safety and quality in accordance with process analytical technology. For estimating the quality of powders without preparation during drug formulation, near-infrared (NIR) spectroscopy has been considered the most promising sensing approach. In this study, we have developed a compact polychromator-type NIR spectrometer equipped with a photodiode (PD) array detector. This detector is consisting of 640 InGaAs-PD elements with 20-μm pitch. Some high-specification spectrometers, which use InGaAs-PD with 512 elements, have a wavelength resolution of about 1.56 nm when covering 900-1700 nm range. On the other hand, the newly developed detector, having the PD with one of the world's highest density, enables wavelength resolution of below 1.25 nm. Moreover, thanks to the combination with a highly integrated charge amplifier array circuit, measurement speed of the detector is higher by two orders than that of existing PD array detectors. The developed spectrometer is small (120 mm × 220 mm × 200 mm) and light (6 kg), and it contains various key devices including the high-density and high-sensitivity PD array detector, NIR technology, and spectroscopy technology for a spectroscopic analyzer that has the required detection mechanism and high sensitivity for powder measurement, as well as a high-speed measuring function for blenders. Moreover, we have evaluated the characteristics of the developed NIR spectrometer, and the measurement of powder samples confirmed that it has high functionality.

  9. A polychromator-type near-infrared spectrometer with a high-sensitivity and high-resolution photodiode array detector for pharmaceutical process monitoring on the millisecond time scale (United States)

    Murayama, Kodai; Genkawa, Takuma; Ishikawa, Daitaro; Komiyama, Makoto; Ozaki, Yukihiro


    In the fine chemicals industry, particularly in the pharmaceutical industry, advanced sensing technologies have recently begun being incorporated into the process line in order to improve safety and quality in accordance with process analytical technology. For estimating the quality of powders without preparation during drug formulation, near-infrared (NIR) spectroscopy has been considered the most promising sensing approach. In this study, we have developed a compact polychromator-type NIR spectrometer equipped with a photodiode (PD) array detector. This detector is consisting of 640 InGaAs-PD elements with 20-μm pitch. Some high-specification spectrometers, which use InGaAs-PD with 512 elements, have a wavelength resolution of about 1.56 nm when covering 900-1700 nm range. On the other hand, the newly developed detector, having the PD with one of the world's highest density, enables wavelength resolution of below 1.25 nm. Moreover, thanks to the combination with a highly integrated charge amplifier array circuit, measurement speed of the detector is higher by two orders than that of existing PD array detectors. The developed spectrometer is small (120 mm × 220 mm × 200 mm) and light (6 kg), and it contains various key devices including the high-density and high-sensitivity PD array detector, NIR technology, and spectroscopy technology for a spectroscopic analyzer that has the required detection mechanism and high sensitivity for powder measurement, as well as a high-speed measuring function for blenders. Moreover, we have evaluated the characteristics of the developed NIR spectrometer, and the measurement of powder samples confirmed that it has high functionality.

  10. InGaAs detectors and FPA's for a large span of applications: design and material considerations (United States)

    Vermeiren, J. P.; Merken, P.


    Compared with the other Infrared detector materials, such as HgCdTe (or MCT) and lead salts (e.g.: PbS, PbSe, PbSnTe, …), the history of InGaAs FPA's is not that old. Some 25 years ago the first linear detectors were used for space missions [1,2]. During the last 15-20 years InGaAs, grown lattice matched on InP, has become the work horse for the telecommunication industry [3] and later on for passive and active imagery in the SWIR range. For longer wavelengths than 1.7 μm, III-V materials are in strong competition with SWIR MCT and till now the performance of MCT is better than high In-content InGaAs. During the last years some alternatives based on quaternary materials [4] and on Superlattice structures [5] are making gradual progress in such a way that they can yield performing Focal planes in the (near) future. As the SWIR wavelengths range covers a large variety of applications, also the FPA characteristics and mainly the ROIC properties need to be adjusted to fulfil the mission requirements with the requested performance. Additionally one has to bear in mind that the nature of SWIR radiation is completely different from what is usually encountered in IR imaging. Whereas the signal of thermal imagery in the Middle Wavelength (MWIR: [3 - 5 μm]) or Long Wavelength (LWIR: [8 - 10 μm] or [8 - 12 μm]) band is characterized by a large DC pedestal, caused by objects at ambient temperature, and a small AC signal, due to the small temperature or emissivity variations, SWIR range imagery is characterized by a large dynamic range and almost no DC signal. In this sense the SWIR imagery is resembling more the nature of Visible and NIR imaging than that of thermal imagery.

  11. Development of Strained-Layer Superlattice (SLS) IR Detector Camera (United States)

    National Aeronautics and Space Administration — Strained Layer Superlattice (SLS) detectors are a new class of detectors which may be the next generation of band-gap engineered, large format infrared detector...

  12. Radiation detectors

    International Nuclear Information System (INIS)


    This sixth chapter presents the operational principles of the radiation detectors; detection using photographic emulsions; thermoluminescent detectors; gas detectors; scintillation detectors; liquid scintillation detectors; detectors using semiconductor materials; calibration of detectors; Bragg-Gray theory; measurement chain and uncertainties associated to measurements

  13. Systematic study of Si-based GeSn photodiodes with 2.6 µm detector cutoff for short-wave infrared detection. (United States)

    Pham, Thach; Du, Wei; Tran, Huong; Margetis, Joe; Tolle, John; Sun, Greg; Soref, Richard A; Naseem, Hameed A; Li, Baohua; Yu, Shui-Qing


    Normal-incidence Ge 1-x Sn x photodiode detectors with Sn compositions of 7 and 10% have been demonstrated. Such detectors were based on Ge/Ge 1-x Sn x /Ge double heterostructures grown directly on a Si substrate via a chemical vapor deposition system. A temperature-dependence study of these detectors was conducted using both electrical and optical characterizations from 300 to 77 K. Spectral response up to 2.6 µm was achieved for a 10% Sn device at room temperature. The peak responsivity and specific detectivity (D*) were measured to be 0.3 A/W and 4 × 10 9 cmHz 1/2 W -1 at 1.55 µm, respectively. The spectral D* of a 7% Sn device at 77 K was only one order-of-magnitude lower than that of an extended-InGaAs photodiode operating in the same wavelength range, indicating the promising future of GeSn-based photodetectors.

  14. HgCdTe APD-based linear-mode photon counting components and ladar receivers (United States)

    Jack, Michael; Wehner, Justin; Edwards, John; Chapman, George; Hall, Donald N. B.; Jacobson, Shane M.


    Linear mode photon counting (LMPC) provides significant advantages in comparison with Geiger Mode (GM) Photon Counting including absence of after-pulsing, nanosecond pulse to pulse temporal resolution and robust operation in the present of high density obscurants or variable reflectivity objects. For this reason Raytheon has developed and previously reported on unique linear mode photon counting components and modules based on combining advanced APDs and advanced high gain circuits. By using HgCdTe APDs we enable Poisson number preserving photon counting. A metric of photon counting technology is dark count rate and detection probability. In this paper we report on a performance breakthrough resulting from improvement in design, process and readout operation enabling >10x reduction in dark counts rate to ~10,000 cps and >104x reduction in surface dark current enabling long 10 ms integration times. Our analysis of key dark current contributors suggest that substantial further reduction in DCR to ~ 1/sec or less can be achieved by optimizing wavelength, operating voltage and temperature.

  15. Growth characteristics of (100)HgCdTe layers in low-temperature MOVPE with ditertiarybutyltelluride (United States)

    Yasuda, K.; Hatano, H.; Ferid, T.; Minamide, M.; Maejima, T.; Kawamoto, K.


    Low-temperature growth of (100)HgCdTe (MCT) layers in MOVPE has been studied using ditertiarybutyltelluride (DtBTe), dimethylcadmium (DMCd), and elementary mercury as precursors. MCT layers were grown at 275°C on (100)GaAs substrates. Growths were carried out in a vertical growth cell which has a narrow spacing between the substrate and cell ceiling. Using the growth cell, the Cd-composition ( x) of MCT layers was controlled over a wide range from 0 to 0.98 by the DMCd flow. The growth rate of the MCT layers was constant at 5 μm h -1 for the increased DMCd flow. Preferential Cd-incorporation into MCT layers and an increase of the growth rate were observed in the presence of mercury vapor. The growth characteristics were considered to be due to the alkyl-exchange reaction between DMCd and mercury. The electrical properties and crystallinity of grown layers were also evaluated, which showed that layers with high quality can be grown at 275°C.

  16. Study of CdTe and HgCdTe thin films obtained by electrochemical methods

    International Nuclear Information System (INIS)

    Guillen, C.


    Cadmium telluride polycrystalline thin films were fabricated on SnO 2 -coated glass substrates by potentiostatic electrodeposition and characterized by X-ray diffraction, energy dispersive X-ray analyses (EDAX), optical and electrical measurements. The films dseposited at potentials more positive than -0.65 V vs.SCE were p-type but those deposited at more negative potentials were n-type. All CdTe thin films showed a band-gap energy about 1.45 eV and a large absorption coeffici-ent (a=10 5 cm -1 ) above de band edge. The addition of even small amounts of mercury to the CdTe produces higuer conductivity values and lower band-gap energies. We have prepared HgCdTe thin films where the band-gap energies ranged between 0.93 and 0.88 eV depending on the ratio of mercury to cadmium. Heat treatment at 300 0 C increases the crystalline diameter and alter the composition of the electrodeposited films, a decrease of the resistivity values was also observed. (Author)

  17. Modelling of current-voltage characteristics of infrared photo-detectors based on type – II InAs/GaSb super-lattice diodes with unipolar blocking layers

    Directory of Open Access Journals (Sweden)

    Vishnu Gopal


    Full Text Available It is shown that current-voltage characteristics of infrared photo-detectors based on type-II InAs/GaSb super-lattices with uni-polar blocking layers can be modelled similar to a junction diode with a finite series resistance on account of blocking barriers. As an example this paper presents the results of a study of current-voltage characteristics of a type II InAs/GaSb super-lattice diode with PbIbN architecture using a recently proposed [J. Appl. Phys. 116, 084502 (2014] method for modelling of illuminated photovoltaic detectors. The thermal diffusion, generation – recombination (g-r, and ohmic currents are found as principal components besides a component of photocurrent due to background illumination. The experimentally observed reverse bias diode current in excess of thermal current (diffusion + g-r, photo-current and ohmic shunt current is reported to be best described by an exponential function of the type, Iexcess = Ir0 + K1exp(K2 V, where Ir0, K1 and K2 are fitting parameters and V is the applied bias voltage. The present investigations suggest that the exponential growth of excess current with the applied bias voltage may be taking place along the localized regions in the diode. These localized regions are the shunt resistance paths on account of the surface leakage currents and/or defects and dislocations in the base of the diode.

  18. Progress towards vertical transport study of proton-irradiated InAs/GaSb type-II strained-layer superlattice materials for space-based infrared detectors using magnetoresistance measurements (United States)

    Malone, Mitchell C.; Morath, Christian P.; Fahey, Stephen; Klein, Brianna; Cowan, Vincent M.; Krishna, Sanjay


    InAs/GaSb type-II strained-layer superlattice (T2SLS) materials are being considered for space-based infrared detector applications. However, an inadequate understanding of the role of carrier transport, specifically the vertical mobility, in the radiation tolerance of T2SLS detectors remains. Here, progress towards a vertical transport study of proton-irradiated, p-type InAs/GaSb T2SLS materials using magnetoresistance measurements is reported. Measurements in the growth direction of square mesas formed from InAs/GaSb superlattice material were performed using two distinct contact geometries in a Kelvin mode setup at variable magnetic fields, ranging from -9 T to 9 T, and temperatures, ranging from 5 K and 300 K. The results here suggested multi-carrier conduction and a field-dependent series resistance from the contact layer were present. The implications of these results and the plans for future magnetoresistance measurements on proton-irradiated T2SLS materials are discussed.

  19. Long wavelength stimulated emission up to 9.5 μm from HgCdTe quantum well heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Morozov, S. V.; Rumyantsev, V. V., E-mail:; Dubinov, A. A.; Kudryavtsev, K. E.; Antonov, A. V.; Gavrilenko, V. I. [Institute for Physics of Microstructures of Russian Academy of Sciences, 603950 Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod, 603950 Nizhny Novgorod (Russian Federation); Kadykov, A. M. [Institute for Physics of Microstructures of Russian Academy of Sciences, 603950 Nizhny Novgorod (Russian Federation); UMR CNRS 5221, GIS-TERALAB, Université Montpellier II, 34095 Montpellier (France); Mikhailov, N. N. [A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Dvoretskii, S. A. [A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation)


    Stimulated emission from waveguide HgCdTe structures with several quantum wells inside waveguide core is demonstrated at wavelengths up to 9.5 μm. Photoluminescence line narrowing down to kT energy, as well as superlinear rise in its intensity evidence the onset of the stimulated emission, which takes place under optical pumping with intensity as small as ∼0.1 kW/cm{sup 2} at 18 K and 1 kW/cm{sup 2} at 80 K. One can conclude that HgCdTe structures potential for long-wavelength lasers is not exhausted.

  20. Radiation detector. [100 A

    Energy Technology Data Exchange (ETDEWEB)

    Baker, P D; Hollands, D V


    A radiation detector is described in which the radiation is led to a sensor via a 100 A thick gold film filter, which reduces the infrared components of the irradiation to a greater extent than the ultra-violet component reaching the sensor.

  1. Choosing a Motion Detector. (United States)

    Ballard, David M.


    Examines the characteristics of three types of motion detectors: Doppler radar, infrared, and ultrasonic wave, and how they are used on school buses to prevent students from being killed by their own school bus. Other safety devices cited are bus crossing arms and a camera monitor system. (MLF)

  2. Semiconductor optoelectronic infrared spectroscopy

    International Nuclear Information System (INIS)

    Hollingworth, A.R.


    We use spectroscopy to study infrared optoelectronic inter and intraband semiconductor carrier dynamics. The overall aim of this thesis was to study both III-V and Pb chalcogenide material systems in order to show their future potential use in infrared emitters. The effects of bandstructure engineering have been studied in the output characteristics of mid-IR III-V laser diodes to show which processes (defects, radiative, Auger and phonon) dominate and whether non-radiative processes can be suppressed. A new three-beam pump probe experiment was used to investigate interband recombination directly in passive materials. Experiments on PbSe and theory for non-parabolic near-mirror bands and non-degenerate statistics were in good agreement. Comparisons with HgCdTe showed a reduction in the Auger coefficient of 1-2 orders of magnitude in the PbSe. Using Landau confinement to model spatial confinement in quantum dots (QDs) 'phonon bottlenecking' was studied. The results obtained from pump probe and cyclotron resonance saturation measurements showed a clear suppression in the cooling of carriers when Landau level separation was not resonant with LO phonon energy. When a bulk laser diode was placed in a magnetic field to produce a quasi quantum wire device the resulting enhanced differential gain and reduced Auger recombination lowered I th by 30%. This result showed many peaks in the light output which occurred when the LO phonon energy was a multiple of the Landau level separation. This showed for the first time evidence of the phonon bottleneck in a working laser device. A new technique called time resolved optically detected cyclotron resonance, was used as a precursor to finding the carrier dynamics within a spatially confined quantum dot. By moving to the case of a spatial QD using an optically detected intraband resonance it was possible to measure the energy separation interband levels and conduction and valence sublevels within the dot simultaneously. Furthermore

  3. Structural properties of layers of HgCdTe, grown by the laser epitaxy method on silicon substrates

    International Nuclear Information System (INIS)

    Plyatsko, S.V.; Vergush, M.M.; Litvin, P.M.; Kozirjev, Yu.M.; Shevlyakov, S.A.


    Thin films (0.1-1.5 μm) of HgCdTe on substrates Si (100) and Si (111) from monocrystal and pressed sources Hg 1-x Cd x Te (x=0.22) sprayed by laser IR radiation were grown and are investigated. The concentration of macro defects (drops) on the surface of films is determined by the relation of the diameter of a laser beam and depth of the crater, formed by laser irradiation. The size of crystal grains almost does not depend on the temperature of a substrate and power densities of a laser radiation and increases with the thickness of a layer

  4. Extended wavelength InGaAs on GaAs using InAlAs buffer for back-side-illuminated short-wave infrared detectors

    International Nuclear Information System (INIS)

    Zimmermann, Lars; John, Joachim; Degroote, Stefan; Borghs, Gustaaf; Hoof, Chris van; Nemeth, Stefan


    We conducted an experimental study of back-side-illuminated InGaAs photodiodes grown on GaAs and sensitive in the short-wave infrared up to 2.4 μm. Standard metamorphic InGaAs or IR-transparent InAlAs buffers were grown by molecular-beam epitaxy. We studied dark current and photocurrent as a function of buffer thickness, buffer material, and temperature. A saturation of the dark current with buffer thickness was not observed. The maximum resistance area product was ∼10 Ω cm2 at 295 K. The dark current above 200 K was dominated by generation-recombination current. A pronounced dependence of the photocurrent on the buffer thickness was observed. The peak external quantum efficiency was 46% (at 1.6 μm) without antireflective coating

  5. Infrared Sky Surveys (United States)

    Price, Stephan D.


    A retrospective is given on infrared sky surveys from Thomas Edison’s proposal in the late 1870s to IRAS, the first sensitive mid- to far-infrared all-sky survey, and the mid-1990s experiments that filled in the IRAS deficiencies. The emerging technology for space-based surveys is highlighted, as is the prominent role the US Defense Department, particularly the Air Force, played in developing and applying detector and cryogenic sensor advances to early mid-infrared probe-rocket and satellite-based surveys. This technology was transitioned to the infrared astronomical community in relatively short order and was essential to the success of IRAS, COBE and ISO. Mention is made of several of the little known early observational programs that were superseded by more successful efforts.

  6. Ionization detector

    International Nuclear Information System (INIS)

    Steele, D.S.


    An ionization detector having an array of detectors has, for example, grounding pads positioned in the spaces between some detectors (data detectors) and other detectors (reference detectors). The grounding pads are kept at zero electric potential, i.e. grounded. The grounding serves to drain away electrons and thereby prevent an unwanted accumulation of charge in the spaces, and cause the electric field lines to be more perpendicular to the detectors in regions near the grounding pads. Alternatively, no empty space is provided there being additional, grounded, detectors provided between the data and reference detectors. (author)

  7. Detector Mount Design for IGRINS

    Directory of Open Access Journals (Sweden)

    Jae Sok Oh


    Full Text Available The Immersion Grating Infrared Spectrometer (IGRINS is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG Focal Plane Array (H2RG FPA detectors. We present the design and fabrication of the detector mount for the H2RG detector. The detector mount consists of a detector housing, an ASIC housing, a Field Flattener Lens (FFL mount, and a support base frame. The detector and the ASIC housing should be kept at 65 K and the support base frame at 130 K. Therefore they are thermally isolated by the support made of GFRP material. The detector mount is designed so that it has features of fine adjusting the position of the detector surface in the optical axis and of fine adjusting yaw and pitch angles in order to utilize as an optical system alignment compensator. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the structural and thermal analysis, the designed detector mount meets an optical stability tolerance and system thermal requirements. Actual detector mount fabricated based on the design has been installed into the IGRINS cryostat and successfully passed a vacuum test and a cold test.

  8. Short-wavelength infrared imaging using low dark current InGaAs detector arrays and vertical-cavity surface-emitting laser illuminators (United States)

    Macdougal, Michael; Geske, Jon; Wang, Chad; Follman, David


    We describe the factors that go into the component choices for a short wavelength IR (SWIR) imager, which include the SWIR sensor, the lens, and the illuminator. We have shown the factors for reducing dark current, and shown that we can achieve well below 1.5 nA/cm2 for 15 μm devices at 7 °C. In addition, we have mated our InGaAs detector arrays to 640×512 readout integrated integrated circuits to make focal plane arrays (FPAs). The resulting FPAs are capable of imaging photon fluxes with wavelengths between 1 and 1.6 μm at low light levels. The dark current associated with these FPAs is extremely low, exhibiting a mean dark current density of 0.26 nA/cm2 at 0 °C. Noise due to the readout can be reduced from 95 to 57 electrons by using off-chip correlated double sampling. In addition, Aerius has developed laser arrays that provide flat illumination in scenes that are normally light-starved. The illuminators have 40% wall-plug efficiency and provide low-speckle illumination, and provide artifact-free imagery versus conventional laser illuminators.

  9. Silicon detectors

    International Nuclear Information System (INIS)

    Klanner, R.


    The status and recent progress of silicon detectors for high energy physics is reviewed. Emphasis is put on detectors with high spatial resolution and the use of silicon detectors in calorimeters. (orig.)

  10. Characterization and Analysis of a Multicolor Quantum Well Infrared Photodetector

    National Research Council Canada - National Science Library

    Hanson, Nathan A


    ...), mid-wavelength infrared (MWIR), and long-wavelength infrared (LWIR). Through photocurrent spectroscopy and performance analysis, this prototype detector can be classified and prepared for possible future use within the U.S. Armed Forces...

  11. Development of Strained-Layer Superlattice (SLS) IR Detector Camera Project (United States)

    National Aeronautics and Space Administration — Strained Layer Superlattice (SLS) detectors are a new class of detectors which may be the next generation of band-gap engineered, large format infrared detector...

  12. Numerical simulation of quantum efficiency and surface recombination in HgCdTe IR photon-trapping structures (United States)

    Schuster, Jonathan; Bellotti, Enrico


    We have investigated the quantum effiency in HgCdTe photovoltaic pixel arrays employing a photon-trapping structure realized with a periodic array of pillars intended to provide broadband operation. We have found that the quantum efficiency depends heavily on the passivation of the pillar surface. Pillars passivated with anodicoxide have a large fixed positive charge on the pillar surface. We use our three-dimensional numerical simulation model to study the effect of surface charge and surface recombination velocity on the exterior of the pillars. We then evaluate the quantum efficiency of this structure subject to different surface conditions. We have found that by themselves, the surface charge and surface recombination are detrimental to the quantum efficiency but the quantum efficiency is recovered when both phenomena are present. We will discuss the effects of these phenomena and the trade offs that exist between the two.

  13. Ultra-low Noise, High Bandwidth, 1550nm HgCdTe APD, Phase II (United States)

    National Aeronautics and Space Administration — To meet the demands of future high-capacity free space optical communications links, a high bandwidth, near infrared (NIR), single photon sensitive optoelectronic...

  14. Transmutation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Viererbl, L., E-mail: vie@ujv.c [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Lahodova, Z. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Klupak, V. [Nuclear Research Institute Rez plc (Czech Republic); Sus, F. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Kucera, J. [Research Centre Rez Ltd. (Czech Republic); Nuclear Physics Institute, Academy of Sciences of the Czech Republic (Czech Republic); Kus, P.; Marek, M. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic)


    We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

  15. Transmutation detectors

    International Nuclear Information System (INIS)

    Viererbl, L.; Lahodova, Z.; Klupak, V.; Sus, F.; Kucera, J.; Kus, P.; Marek, M.


    We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

  16. Far infrared photoconductors

    International Nuclear Information System (INIS)

    Leotin, J.; Meny, C.


    This paper presents the development of far infrared photoconductors for the focal plane of a spaceborne instrument named SAFIRE. SAFIRE (Spectroscopy of the Atmosphere using Far-Infrared Emission) belongs to the EOS program (Earth Observing System) and is now in the definition phase. It is a joint effort by scientists from the United States, Great Britain, Italy and France for a new generation of atmosphere sensor. The overall goal of the SAFIRE experiment is to improve the understanding of the ozone distribution in the middle atmosphere by conducting global scale measurements of the important chemical, radiative and dynamical processes which influence its changes. This will be accomplished by the measurement of the far infrared thermal limb emission in seven spectral channels covering the range 80 to 400 cm -1 with a maximum resolution of 0.004 cm -1 . For example key gases like OH, O, HO 2 , N 2 O 5 will be probed for the first time. Achievement of the required detector sensitivity in the far-infrared imposes the choice of photoconductive detectors operating at liquid helium temperatures. Germanium doped with gallium is selected for six channels whereas germanium doped with beryllium is suitable for the N 2 O 5 channel. Both photoconductors Ge:Ga and Ge:Be benefit from a well established material technology. A better wavelength coverage of channel 1 is achieved by applying a small uniaxial stress of the order of 0.1 GPa on the Ge:Ga photoconductors. The channel 6B wavelength coverage could be improved by using zinc-doped-germanium (Ge:Zn) or, much better, by using a Blocked Impurity band silicon detector doped with antimony (BIB Si:Sb). The later is developed as an optional basis

  17. Detector Unit

    CERN Multimedia


    Original detector unit of the Instituut voor Kernfysisch Onderzoek (IKO) BOL project. This detector unit shows that silicon detectors for nuclear physics particle detection were already developed and in use in the 1960's in Amsterdam. Also the idea of putting 'strips' onto the silicon for high spatial resolution of a particle's impact on the detector were implemented in the BOL project which used 64 of these detector units. The IKO BOL project with its silicon particle detectors was designed, built and operated from 1965 to roughly 1977. Detector Unit of the BOL project: These detectors, notably the ‘checkerboard detector’, were developed during the years 1964-1968 in Amsterdam, The Netherlands, by the Natuurkundig Laboratorium of the N.V. Philips Gloeilampen Fabrieken. This was done in close collaboration with the Instituut voor Kernfysisch Onderzoek (IKO) where the read-out electronics for their use in the BOL Project was developed and produced.

  18. Detector trends

    International Nuclear Information System (INIS)

    Charpak, G.


    The author describes briefly the development of detectors for high energy physics experiments. Especially considered are semiconductor microstrip detectors, drift tubes, holographic bubble chambers, scintillating fiber optics, and calorimeters. (HSI).

  19. A flexible infrared sensor for tissue oximetry

    DEFF Research Database (Denmark)

    Petersen, Søren Dahl; Thyssen, Anders; Engholm, Mathias


    We present a flexible infrared sensor for use in tissue oximetry with the aim of treating prematurely born infants. The sensor will detect the oxygen saturation in brain tissue through near infrared spectroscopy. The sensor itself consists of several individual silicon photo detectors fully...

  20. Long-wave Infrared Detectors for the Planetary Infrared Spectrometers (United States)

    National Aeronautics and Space Administration — Understanding the role of primitive bodies as building blocks for planets and life are key targets for space exploration. Chemical and mineralogical...

  1. Center for Research on Infrared Detectors (CENTROID) (United States)


    of growth, x is also monitored in situ by SE, and Tis measured by a thermocouple, a pyrometer and indirectly by the heating power and is calibrated...Polar optical, acoustic , and inter-valley phonon scattering are included, as wells as scattering from the quantum dots. The simulation includes

  2. Infrared astronomy

    International Nuclear Information System (INIS)

    Setti, G.; Fazio, G.


    This volume contains lectures describing the important achievements in infrared astronomy. The topics included are galactic infrared sources and their role in star formation, the nature of the interstellar medium and galactic structure, the interpretation of infrared, optical and radio observations of extra-galactic sources and their role in the origin and structure of the universe, instrumental techniques and a review of future space observations. (C.F.)

  3. Latest improvements on long wave p on n HgCdTe technology at Sofradir (United States)

    Rubaldo, Laurent; Taalat, Rachid; Berthoz, Jocelyn; Maillard, Magalie; Péré-Laperne, Nicolas; Brunner, Alexandre; Guinedor, Pierre; Dargent, L.; Manissadjian, A.; Reibel, Y.; Kerlain, A.


    SOFRADIR is the worldwide leader on the cooled IR detector market for high-performance space, military and security applications thanks to a well mastered Mercury Cadmium Telluride (MCT) technology, and recently thanks to the acquisition of III-V technology: InSb, InGaAs, and QWIP quantum detectors. As a result, strong and continuous development efforts are deployed to deliver cutting edge products with improved performances in terms of spatial and thermal resolution, dark current, quantum efficiency, low excess noise and high operability. The actual trend in quantum IR detector development is the design of very small pixel, with the higher achievable operating temperature whatever the spectral band. Moreover maintaining the detector operability and image quality at higher temperature moreover for long wavelength is a major issue. This paper presents the recent developments achieved at Sofradir to meet this challenge for LW band MCT extrinsic p on n technology with a cut-off wavelength of 9.3μm at 90K. State of the art performances will be presented in terms of dark current, operability and NETD temperature dependency, quantum efficiency, MTF, and RFPN (Residual Fixed Pattern Noise) stability up to 100K.

  4. Science with low temperature detectors

    International Nuclear Information System (INIS)

    Sadoulet, B.; Lawrence Berkeley National Lab., CA; California Univ., Berkeley


    The novel technique of particle detection with low temperature detectors opens a number of new scientific opportunities. We review some of these, focusing on three generic applications: far infrared bolometry taking as an example the cosmic microwave background, X-ray spectroscopy for astrophysics and biological applications, and massive calorimeters for dark matter searches and neutrino physics. (orig.)

  5. Novel Photon-Counting Detectors for Free-Space Communication (United States)

    Krainak, Michael A.; Yang, Guan; Sun, Xiaoli; Lu, Wei; Merritt, Scott; Beck, Jeff


    We present performance data for novel photon counting detectors for free space optical communication. NASA GSFC is testing the performance of three novel photon counting detectors 1) a 2x8 mercury cadmium telluride avalanche array made by DRS Inc. 2) a commercial 2880 silicon avalanche photodiode array and 3) a prototype resonant cavity silicon avalanche photodiode array. We will present and compare dark count, photon detection efficiency, wavelength response and communication performance data for these detectors. We discuss system wavelength trades and architectures for optimizing overall communication link sensitivity, data rate and cost performance. The HgCdTe APD array has photon detection efficiencies of greater than 50 were routinely demonstrated across 5 arrays, with one array reaching a maximum PDE of 70. High resolution pixel-surface spot scans were performed and the junction diameters of the diodes were measured. The junction diameter was decreased from 31 m to 25 m resulting in a 2x increase in e-APD gain from 470 on the 2010 array to 1100 on the array delivered to NASA GSFC. Mean single photon SNRs of over 12 were demonstrated at excess noise factors of 1.2-1.3.The commercial silicon APD array has a fast output with rise times of 300ps and pulse widths of 600ps. Received and filtered signals from the entire array are multiplexed onto this single fast output. The prototype resonant cavity silicon APD array is being developed for use at 1 micron wavelength.

  6. Observation of galactic far-infrared ray

    International Nuclear Information System (INIS)

    Maihara, Toshinori; Oda, Naoki; Okuda, Haruyuki; Sugiyama, Takuya; Sakai, Kiyomi.


    Galactic far-infrared was observed to study the spatial distribution of interstellar dust. Far-infrared is emitted by interstellar dust distributing throughout the galactic plane. The observation of far-infrared is very important to study the overall structure of the galaxy, that is the structure of the galactic arm and gas distribution. The balloon experiment was conducted on May 25, 1978. The detector was a germanium bolometer cooled by liquid helium. The size of the detector is 1.6 mm in diameter. The geometrical factor was 4 x 10 3 cm 2 sr. The result showed that the longitude distribution of far-infrared at 150 μm correlated with H 166 α recombination line. This indicates that the observed far-infrared is emitted by interstellar dust heated by photons of Lyman continuum. (Yoshimori, M.)

  7. Technique of infrared synchrotron acceleration diagnostics

    International Nuclear Information System (INIS)

    Mal'tsev, A.A.; Mal'tsev, M.A.


    Techniques of measuring of current and geometric parameters and evaluating of energy parameters of the ring bunch of relativistic low-energy electrons have been presented. They have been based on using the synchrotron radiation effect in its infrared spectral part. Fast infrared detectors have provided radiation detection in the spectral range Δλ ≅ 0.3-45 μm. The descriptions of some data monitoring and measuring systems developed in JINR for the realization of techniques of the infrared synchrotron acceleration diagnostics have been given. Infrared optics elements specially developed have been used in these systems

  8. Applications of infrared technology; Proceedings of the Meeting, London, England, June 9, 10, 1988

    International Nuclear Information System (INIS)

    Williams, T.L.


    Recent developments in thermal imaging and other infrared systems relating to military, industrial, medical, and scientific applications are reviewed. Papers are presented on a new thermal imager using a linear pyroelectric detector array; multichannel near infrared spectroradiometer; technological constraints on the use of thermal imagery for remote sensing; and infrared optical system of the improved stratospheric and mesospheric sounder. Other topics discussed include infrared thermography development for composite material evaluation; infrared process linescanner, and optical infrared starting radiometer

  9. Cryogenic detectors

    International Nuclear Information System (INIS)

    Zehnder, A.


    Presently the development of new large scale detector systems, used in very high energy physics experiments, is very active. In the low energy range, the introduction of charge coupled devices allows improved spacial and energy resolution. In the keV region, high resolution can only be achieved via the well established diffraction spectrometers with the well-known disadvantage of a small throughput. There exist no efficient detectors for non-ionizing radiation such as coherent nuclear scattering of weakly interacting particles. The development of high resolution solid state detectors in the keV-region with the possibility of nuclear recoil detection is therefore highly desired. Such detectors applied in astro and particle physics would thus allow one to obtain new information not achievable otherwise. Three types of cryogenic detectors exist: Calorimeters/Bolometers. This type is sensitive to the produced excess phonons and measures the deposited energy by detecting the heat pulses. Excess charge carriers should be used to produce phonons. Tunneling junctions. This type is sensitive to excess charge produced by the Cooper pair breakup. Excess phonons should be used to break up Cooper pairs. Superheated superconducting granules (SSG). An SSG detector consists of granules, the metastability of which is disturbed by radiation. The Meissner effect then causes a change in the field distribution of the applied external field, which can be detected. The present paper discusses the basic principle of calorimetric and tunneling junction detectors and some of their applications. 26 refs., 7 figs., 1 tab

  10. Growth and Characterization of (211)B Cadmium Telluride Buffer Layer Grown by Metal-organic Vapor Phase Epitaxy on Nanopatterned Silicon for Mercury Cadmium Telluride Based Infrared Detector Applications (United States)

    Shintri, Shashidhar S.

    Mercury cadmium telluride (MCT or Hg1-xCdxTe) grown by molecular beam epitaxy (MBE) is presently the material of choice for fabricating infrared (IR) detectors used in night vision based military applications. The focus of MCT epitaxy has gradually shifted since the last decade to using Si as the starting substrate since it offers several advantages. But the ˜19 % lattice mismatch between MCT and Si generates lots of crystal defects some of which degrade the performance of MCT devices. Hence thick CdTe films are used as buffer layers on Si to accommodate the defects. However, growth of high quality single crystal CdTe on Si is challenging and to date, the best MBE CdTe/Si reportedly has defects in the mid-105 cm -2 range. There is a critical need to reduce the defect levels by at least another order of magnitude, which is the main motivation behind the present work. The use of alternate growth technique called metal-organic vapor phase epitaxy (MOVPE) offers some advantages over MBE and in this work MOVPE has been employed to grow the various epitaxial films. In the first part of this work, conditions for obtaining high quality (211)B CdTe epitaxy on (211)Si were achieved, which also involved studying the effect of having additional intermediate buffer layers such as Ge and ZnTe and incorporation of in-situ thermal cyclic annealing (TCA) to reduce the dislocation density. A critical problem of Si cross-contamination due to 'memory effect' of different reactant species was minimized by introducing tertiarybutylArsine (TBAs) which resulted in As-passivation of (211)Si. The best 8-10 µm thick CdTe films on blanket (non-patterned) Si had dislocations around 3×105 cm-2, which are the best reported by MOVPE till date and comparable to the highest quality films available by MBE. In the second part of the work, nanopatterned (211)Si was used to study the effect of patterning on the crystal quality of epitaxial CdTe. In one such study, patterning of ˜20 nm holes in SiO2

  11. Detectors - Electronics

    International Nuclear Information System (INIS)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J.


    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X → e - converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the 3 He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  12. Conceptual thermal design and analysis of a far-infrared/mid-infrared remote sensing instrument (United States)

    Roettker, William A.


    This paper presents the conceptual thermal design and analysis results for the Spectroscopy of the Atmosphere using Far-Infrared Emission (SAFIRE) instrument. SAFIRE has been proposed for Mission to Planet Earth to study ozone chemistry in the middle atmosphere using remote sensing of the atmosphere in the far-infrared (21-87 microns) and mid-infrared (9-16 microns) spectra. SAFIRE requires that far-IR detectors be cooled to 3-4 K and mid-IR detectors to 80 K for the expected mission lifetime of five years. A superfluid helium dewar and Stirling-cycle cryocoolers provide the cryogenic temperatures required by the infrared detectors. The proposed instrument thermal design uses passive thermal control techniques to reject 465 watts of waste heat from the instrument.

  13. Hydrogen detector

    International Nuclear Information System (INIS)

    Kumagaya, Hiromichi; Yoshida, Kazuo; Sanada, Kazuo; Chigira, Sadao.


    The present invention concerns a hydrogen detector for detecting water-sodium reaction. The hydrogen detector comprises a sensor portion having coiled optical fibers and detects hydrogen on the basis of the increase of light transmission loss upon hydrogen absorption. In the hydrogen detector, optical fibers are wound around and welded to the outer circumference of a quartz rod, as well as the thickness of the clad layer of the optical fiber is reduced by etching. With such procedures, size of the hydrogen detecting sensor portion can be decreased easily. Further, since it can be used at high temperature, diffusion rate is improved to shorten the detection time. (N.H.)

  14. RF sputtered HgCdTe films for tandem cell applications

    International Nuclear Information System (INIS)

    Wang, S.L.; Lee, S.H.; Gupta, A.; Compaan, A.D.


    Polycrystalline Hg 1-x Cd x Te films were investigated for their potential as bottom cells of a CdTe-based tandem solar cell. The films were deposited by RF sputtering from a cold pressed target containing 30% HgTe+70% CdTe. The as-deposited films were highly resistive with (111) preferred orientation and a bandgap of ∝1.0 eV. Various thermal treatment schemes were investigated under different conditions of ambient and temperature to reduce the resistivity. The film properties were analyzed using infrared transmission spectra, energy dispersive X-ray spectra and X-ray diffraction. N doped p-HgCdTe films were also prepared by reactive sputtering in a N 2 /Ar ambient. P-n junction solar cells were fabricated with CdS films as the heterojunction partner. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. DUMAND detector

    CERN Multimedia

    This object is one of the 256 other detectors of the DUMAND (Deep Underwater Muon And Neutrino Detection) experiment. The goal of the experiment was the construction of the first deep ocean high energy neutrino detector, to be placed at 4800 m depth in the Pacific Ocean off Keahole Point on the Big Island of Hawaii. A few years ago, a European conference with Cosmic experiments was organized at CERN as they were projects like DUMAND in Hawaii. Along with the conference, a temporary exhibition was organised as well. It was a collaboration of institutions from Germany, Japan, Switzerland and the U.S.A. CERN had borrowed equipment and objects from different institutes around the world, including this detector of the DUMAND experiment. Most of the equipment were sent back to the institutes, however this detector sphere was offered to a CERN member of the personnel.

  16. Detector applications

    International Nuclear Information System (INIS)

    Pehl, R.H.


    Semiconductor detectors are now applied to a very wide range of problems. The combination of relatively low cost, excellent energy resolution, and simultaneous broad energy-spectrum analysis is uniquely suited to many applications in both basic and applied physics. Alternative techniques, such as magnetic spectrometers for charged-particle spectroscopy, while offering better energy resolution, are bulky, expensive, and usually far more difficult to use. Furthermore, they do not directly provide the broad energy-spectrum measurements easily accomplished using semiconductor detectors. Scintillation detectors, which are approximately equivalent to semiconductor detectors in convenience and cost, exhibit 10 to 100 times worse energy resolution. However, their high efficiency and large potential size recommend their use in some measurements

  17. Smoke detectors

    International Nuclear Information System (INIS)

    Bryant, J.; Howes, J.H.; Smout, D.W.S.


    A smoke detector is described which provides a smoke sensing detector and an indicating device and in which a radioactive substance is used in conjunction with two ionisation chambers. The system includes an outer electrode, a collector electrode and an inner electrode which is made of or supports the radioactive substance which, in this case, is 241 Am. The invention takes advantage of the fact that smoke particles can be allowed to enter freely the inner ionisation chamber. (U.K.)

  18. Radiation detector

    International Nuclear Information System (INIS)

    Gillies, W.


    The radiation detector for measuring e.g. a neutron flux consists of a central emitter, an insulating shell arranged around it, and a tube-shaped collector enclosing both. The emitter itself is composed of a great number of stranded, spiral wires of small diameter giving a defined flexibility to the detector. For emitter material Pt, Rh, V, Co, Ce, Os or Ta may be used. (DG) [de

  19. Shaped detector

    International Nuclear Information System (INIS)

    Carlson, R.W.


    A radiation detector or detector array which has a non-constant spatial response, is disclosed individually and in combination with a tomographic scanner. The detector has a first dimension which is oriented parallel to the plane of the scan circle in the scanner. Along the first dimension, the detector is most responsive to radiation received along a centered segment of the dimension and less responsive to radiation received along edge segments. This non-constant spatial response can be achieved in a detector comprised of a scintillation crystal and a photoelectric transducer. The scintillation crystal in one embodiment is composed of three crystals arranged in layers, with the center crystal having the greatest light conversion efficiency. In another embodiment, the crystal is covered with a reflective substance around the center segment and a less reflective substance around the remainder. In another embodiment, an optical coupling which transmits light from adjacent the center segment with the greatest intensity couples the scintillation crystal and the photoelectric transducer. In yet another embodiment, the photoelectric transducer comprises three photodiodes, one receiving light produced adjacent the central segment and the other two receiving light produced adjacent the edge segments. The outputs of the three photodiodes are combined with a differential amplifier

  20. Quantum Well Infrared Photodetectors: Device Physics and Light Coupling (United States)

    Bandara, S. V.; Gunapala, S. D.; Liu, J. K.; Mumolo, J.; Luong, E.; Hong, W.; Sengupta, D. K.


    It is customary to make infrared (IR) detectors in the long wavelength range by utilizing the interband transition which promotes an electron across the band gap (Eg) from the valence band to the conduction.

  1. BES detector

    International Nuclear Information System (INIS)

    Bai, J.Z.; Bian, Q.; Chen, G.M.; Chen, L.J.; Chen, S.N.; Chen, Y.Q.; Chen, Z.Q.; Chi, Y.K.; Cui, H.C.; Cui, X.Z.; Deng, S.S.; Deng, Y.W.; Ding, H.L.; Dong, B.Z.; Dong, X.S.; Du, X.; Du, Z.Z.; Feng, C.; Feng, Z.; Fu, Z.S.; Gao, C.S.; Gao, M.L.; Gao, S.Q.; Gao, W.X.; Gao, Y.N.; Gu, S.D.; Gu, W.X.; Guan, Y.Z.; Guo, H.F.; Guo, Y.N.; Guo, Y.Y.; Han, S.W.; Han, Y.; Hao, W.; He, J.; He, K.R.; He, M.J.; Hou, X.J.; Hu, G.Y.; Hu, J.S.; Hu, J.W.; Huang, D.Q.; Huang, Y.Z.; Jia, Q.P.; Jiang, C.H.; Ju, Q.; Lai, Y.F.; Lang, P.F.; Li, D.S.; Li, F.; Li, H.; Li Jia; Li, J.T.; Li Jin; Li, L.L.; Li, P.Q.; Li, Q.M.; Li, R.B.; Li, S.Q.; Li, W.; Li, W.G.; Li, Z.X.; Liang, G.N.; Lin, F.C.; Lin, S.Z.; Lin, W.; Liu, Q.; Liu, R.G.; Liu, W.; Liu, X.; Liu, Z.A.; Liu, Z.Y.; Lu, C.G.; Lu, W.D.; Lu, Z.Y.; Lu, J.G.; Ma, D.H.; Ma, E.C.; Ma, J.M.; Mao, H.S.; Mao, Z.P.; Meng, X.C.; Ni, H.L.; Nie, J.; Nie, Z.D.; Niu, W.P.; Pan, L.J.; Qi, N.D.; Qian, J.J.; Qu, Y.H.; Que, Y.K.; Rong, G.; Ruan, T.Z.; Shao, Y.Y.; Shen, B.W.; Shen, D.L.; Shen, J.; Sheng, H.Y.; Sheng, J.P.; Shi, H.Z.; Song, X.F.; Sun, H.S.; Tang, F.K.; Tang, S.Q.; Tian, W.H.; Wang, F.; Wang, G.Y.; Wang, J.G.; Wang, J.Y.; Wang, L.S.; Wang, L.Z.; Wang, M.; Wang, P.; Wang, P.L.; Wang, S.M.; Wang, S.Q.; Wang, T.J.; Wang, X.W.; Wang, Y.Y.; Wang, Z.H.; Wang, Z.J.; Wei, C.L.; Wei, Z.Z.; Wu, J.W.; Wu, S.H.; Wu, S.Q.; Wu, W.M.; Wu, X.D.; Wu, Z.D.; Xi, D.M.; Xia, X.M.; Xiao, J.; Xie, P.P.; Xie, X.X.; Xu, J.G.; Xu, R.S.; Xu, Z.Q.; Xuan, B.C.; Xue, S.T.; Yan, J.; Yan, S.P.; Yan, W.G.; Yang, C.Z.; Yang, C.M.; Yang, C.Y.; Yang, X.F.; Yang, X.R.; Ye, M.H.; Yu, C.H.; Yu, C.S.; Yu, Z.Q.; Zhang, B.Y.; Zhang, C.D.; Zhang, C.C.; Zhang, C.Y.; Zhang, D.H.; Zhang, G.; Zhang, H.Y.; Zhang, H.L.; Zhang, J.W.; Zhang, L.S.; Zhang, S.Q.; Zhang, Y.P.; Zhang, Y.; Zhang, Y.M.; Zhao, D.X.; Zhao, J.W.; Zhao, M.; Zhao, P.D.; Zhao, P.P.; Zhao, W.R.; Zhao, Z.G.; Zhao, Z.Q.; Zheng, J.P.; Zheng, L.S.; Zheng, M.; Zheng, W.S.; Zheng, Z.P.; Zhong, G.P.; Zhou, G.P.; Zhou, H.S.; Zhou, J.; Zhou Li; Zhou Lin; Zhou, M.; Zhou, Y.S.; Zhou, Y.H.; Zhu, G.S.; Zhu, Q.M.; Zhu, S.G.; Zhu, Y.C.; Zhu, Y.S.; Zhuang, B.A.


    The Beijing Spectrometer (BES) is a general purpose solenoidal detector at the Beijing Electron Positron Collider (BEPC). It is designed to study exclusive final states in e + e - annihilations at the center of mass energy from 3.0 to 5.6 GeV. This requires large solid angle coverage combined with good charged particle momentum resolution, good particle identification and high photon detection efficiency at low energies. In this paper we describe the construction and the performance of BES detector. (orig.)

  2. Heterojunction Structures for Photon Detector Applications (United States)


    IR: Fourier-transform infrared FTO: Fluorine doped tin oxide G-R: generation-recombination HEIWIP: heterojunction interfacial workfunction internal...SECURITY CLASSIFICATION OF: The work presented here report findings in (1) infrared detectors based on p-GaAs/AlGaAs heterojunctions , (2) J and H...aggregate sensitized heterojunctions for solar cell and photon detection applications, (3) heterojunctions sensitized with quantum dots as low cost

  3. Spectral Irradiance Measurements Based on Detector

    International Nuclear Information System (INIS)

    Lima, M S; Menegotto, T; Duarte, I; Da Silva, T Ferreira; Alves, L C; Alvarenga, A D; Almeida, G B; Couceiro, I B; Teixeira, R N


    This paper presents the preliminary results of the realization of absolute spectral irradiance scale at INMETRO in the ultraviolet, visible and infrared regions using filter radiometers as secondary standards. In the construction of these instruments are used, at least, apertures, interference filters and a trap detector. In the assembly of the trap detectors it was necessary to characterize several photocells in spatial uniformity and shunt resistance. All components were calibrated and these results were analyzed to mount the filter radiometer

  4. Infrared thermography on TFR 600 Tokamak

    International Nuclear Information System (INIS)

    Romain, Roland.


    Infrared thermography with a single InSb detector and with a scanning camera has been performed on the TFR fusion device. High power neutral beam injection diagnostic by means of an infrared periscope is showed to be possible. Surface temperature measurements on the limiter during the discharge have been made in order to evaluate the power deposited by the plasma on this part of the inner wall. Various attempts of infrared detection on the high power neutral injector prototype vessel are described, particularly the measurement of the power deposited on one of the extraction grids of the ion source [fr

  5. Vertex detectors

    International Nuclear Information System (INIS)

    Lueth, V.


    The purpose of a vertex detector is to measure position and angles of charged particle tracks to sufficient precision so as to be able to separate tracks originating from decay vertices from those produced at the interaction vertex. Such measurements are interesting because they permit the detection of weakly decaying particles with lifetimes down to 10 -13 s, among them the τ lepton and charm and beauty hadrons. These two lectures are intended to introduce the reader to the different techniques for the detection of secondary vertices that have been developed over the past decades. The first lecture includes a brief introduction to the methods used to detect secondary vertices and to estimate particle lifetimes. It describes the traditional technologies, based on photographic recording in emulsions and on film of bubble chambers, and introduces fast electronic registration of signals derived from scintillating fibers, drift chambers and gaseous micro-strip chambers. The second lecture is devoted to solid state detectors. It begins with a brief introduction into semiconductor devices, and then describes the application of large arrays of strip and pixel diodes for charged particle tracking. These lectures can only serve as an introduction the topic of vertex detectors. Time and space do not allow for an in-depth coverage of many of the interesting aspects of vertex detector design and operation

  6. Smoke detectors

    International Nuclear Information System (INIS)

    Macdonald, E.


    A smoke detector is described consisting of a ventilated ionisation chamber having a number of electrodes and containing a radioactive source in the form of a foil supported on the surface of the electrodes. This electrode consists of a plastic material treated with graphite to render it electrically conductive. (U.K.)

  7. Semiconductor Detectors

    International Nuclear Information System (INIS)

    Cortina, E.


    Particle detectors based on semiconductor materials are among the few devices used for particle detection that are available to the public at large. In fact we are surrounded by them in our daily lives: they are used in photoelectric cells for opening doors, in digital photographic and video camera, and in bar code readers at supermarket cash registers. (Author)

  8. Capillary detectors

    International Nuclear Information System (INIS)

    Konijn, J.; Winter, K.; Vilain, P.; Wilquet, G.; Fabre, J.P.; Kozarenko, E.; Kreslo, I.; Goldberg, J.; Hoepfner, K.; Bay, A.; Currat, C.; Koppenburg, P.; Frekers, D.; Wolff, T.; Buontempo, S.; Ereditato, A.; Frenkel, A.; Liberti, B.; Martellotti, G.; Penso, G.; Ekimov, A.; Golovkin, S.; Govorun, V.; Medvedkov, A.; Vasil'chenko, V.


    The option for a microvertex detector using glass capillary arrays filled with liquid scintillator is presented. The status of capillary layers development and possible read-out techniques for high rate environment are reported. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. A polychromator-type near-infrared spectrometer with a high-sensitivity and high-resolution photodiode array detector for pharmaceutical process monitoring on the millisecond time scale


    Murayama, Kodai; Genkawa, Takuma; Ishikawa, Daitaro; Komiyama, Makoto; Ozaki, Yukihiro


    In the fine chemicals industry, particularly in the pharmaceutical industry, advanced sensing technologies have recently begun being incorporated into the process line in order to improve safety and quality in accordance with process analytical technology. For estimating the quality of powders without preparation during drug formulation, near-infrared (NIR) spectroscopy has been considered the most promising sensing approach. In this study, we have developed a compact polychromator-type NIR s...

  10. Measurement of infrared optical constants with visible photons (United States)

    Paterova, Anna; Yang, Hongzhi; An, Chengwu; Kalashnikov, Dmitry; Krivitsky, Leonid


    We demonstrate a new scheme for infrared spectroscopy with visible light sources and detectors. The technique relies on the nonlinear interference of correlated photons, produced via spontaneous parametric down conversion in a nonlinear crystal. Visible and infrared photons are split into two paths and the infrared photons interact with the sample under study. The photons are reflected back to the crystal, resembling a conventional Michelson interferometer. Interference of the visible photons is observed and it is dependent on the phases of all three interacting photons: pump, visible and infrared. The transmission coefficient and the refractive index of the sample in the infrared range can be inferred from the interference pattern of visible photons. The method does not require the use of potentially expensive and inefficient infrared detectors and sources, it can be applied to a broad variety of samples, and it does not require a priori knowledge of sample properties in the visible range.

  11. Barriers Keep Drops Of Water Out Of Infrared Gas Sensors (United States)

    Murray, Sean K.


    Infrared-sensor cells used for measuring partial pressures of CO(2) and other breathable gases modified to prevent entry of liquid water into sensory optical paths of cells. Hydrophobic membrane prevents drops of water entrained in flow from entering optical path from lamp to infrared detectors.


    A portable Fourier transform infrared gas analyzer with a photoacoustic detector performed reliably during pollution prevention research at two industrial facilities. It exhibited good agreement (within approximately 6%) with other analytical instruments (dispersive infrared and ...

  13. Near Infrared Spectroscopy Systems for Tissue Oximetry

    DEFF Research Database (Denmark)

    Petersen, Søren Dahl

    for other medical applications. The tissue oximeters are realised by incorporation of pn-diodes into the silicon in order to form arrays of infrared detectors. These arrays can then be used for spatially resolved spectroscopy measurements, with the targeted end user being prematurely born infant children...

  14. Infrared radiation from dark globules

    International Nuclear Information System (INIS)

    Spencer, R.G.; Leung, C.M.


    Theoretical models are constructed by which to study the infrared emission from dark globules heated by the interstellar radiation field (ISRF). The effects of cloud parameters (grain type, optical depth, and density inhomogeneity) on the emergent spectrum and infrared surface brightnesses are studied. Compared with clouds which have internal heat sources, the emergent flux for globules is found to be at least a factor of 10 smaller and to peak at wavelengths 100 μm< or =lambda< or =130 μm for graphite clouds and 310 μm< or =lambda< or =550 μm for silicate clouds. Either limb brightening or limb darkening in the infrared can occur, which depends sensitively on the optical depth. For globules of moderate extinction (greater than approx.10 in the visible), significant infrared limb brightening occurs at wavelengths of grain emission (20 μm< or =lambda< or =600 μm). A physical interpretation of these results is presented. To help remove ambiguities from interpretations of future observations, the observable effects of a grain mixture, variation of the ISRF, as well as beam dilution are examined in detail. The presence of a second grain component alters the emergent spectrum significantly. For a variation of the ISRF within wide limits, the ratio of surface to central temperature (T/sub s//T/sub c/) of an optically thick cloud remains fairly constant (3< or approx. =T/sub s//T/sub c/< or approx. =4). Infrared limb brightening may be smoothed out by beam dilution as well as by density inhomogeneities. Finally, the expected flux densities in the infrared of a typical globule are presented for different beam sizes. The predicted fluxes are within the detection threshold of currently available infrared detectors, using either ground-based or balloon-borne telescopes

  15. Neutron detector (United States)

    Stephan, Andrew C [Knoxville, TN; Jardret,; Vincent, D [Powell, TN


    A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

  16. Ionization detector

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, E E


    This invention concerns a fire detection system making use of a beta source. The ionisation detector includes a first and second chamber respectively comprising a first and second electrode, preferably a plate, with a common electrode separating the first and second chamber. Communication is provided between these chambers through a set of orifices and each chamber also has a set of orifices for communication with the ambient atmosphere. One or both chambers can comprise a particle source, preferably beta. The detector also has an adjustable electrode housed in one of the chambers to regulate the voltage between the fixed electrode of this chamber and the common electrode located between the chambers. The electrodes of the structure are connected to a detection circuit that spots a change in the ionisation current when a fire alarm condition arises. The detection circuit of a new type includes a relaxation oscillator with a programmable unijunction transistor and a light emitting diode.

  17. MUST detector

    International Nuclear Information System (INIS)

    Blumenfeld, Y.; Auger, F.; Sauvestre, J.E.


    The IPN-Orsay, in collaboration with the SPhN-Saclay and the DPTA Bruyeres, has built an array of 8 telescopes based on Si-strip technology for the study of direct reactions induced by radioactive beams. The detectors are described, along with the compact high density VXI electronics and the stand-alone data acquisition system developed in the laboratory. One telescope was tested using an 40 Ar beam and the measured performances are discussed. (authors)

  18. Radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Ohata, Shuichi; Takeuchi, Yoji


    Herein disclosed is an ionization chamber the airtightness of which can be readily tested. The ionization chamber is characterized in that a small amount of helium gas is filled in the chamber in combination with other ionization gases such as argon gas, xenon gas and the like. Helium leakage from the chamber is measured by a known helium gas sensor in a vacuum vessel. Hence the long term drift of the radiation detector sensitivity may be determined.

  19. Fabrication of Ultrasensitive Transition Edge Sensor Bolometric Detectors for HIRMES (United States)

    Brown, Ari-David; Brekosky, Regis; Franz, David; Hsieh, Wen-Ting; Kutyrev, Alexander; Mikula, Vilem; Miller, Timothy; Moseley, S. Harvey; Oxborrow, Joseph; Rostem, Karwan; hide


    The high resolution mid-infrared spectrometer (HIRMES) is a high resolving power (R approx. 100,000) instrument operating in the 25-122 micron spectral range and will fly on board the Stratospheric Observatory for Far-Infrared Astronomy (SOFIA) in 2019. Central ot HIRMES are its two transition edge sensor (TES) bolometric cameras, an 8x16 detector high resolution array and a 64x16 detector low resolution array. Both types of detectors consist of MoAu TES fabricated on leg-isolated Si membranes. Whereas the high resolution detectors, with noise equivalent power (NEP) approx. 2 aW/square root of (Hz), are fabricated on 0.45 micron Si substrates, the low resolution detectors, with NEP approx. 10 aW/square root of (Hz), are fabricated on 1.40 micron Si. Here we discuss the similarities and difference in the fabrication methodologies used to realize the two types of detectors.

  20. Infrared Heaters (United States)


    The heating units shown in the accompanying photos are Panelbloc infrared heaters, energy savers which burn little fuel in relation to their effective heat output. Produced by Bettcher Manufacturing Corporation, Cleveland, Ohio, Panelblocs are applicable to industrial or other facilities which have ceilings more than 12 feet high, such as those pictured: at left the Bare Hills Tennis Club, Baltimore, Maryland and at right, CVA Lincoln- Mercury, Gaithersburg, Maryland. The heaters are mounted high above the floor and they radiate infrared energy downward. Panelblocs do not waste energy by warming the surrounding air. Instead, they beam invisible heat rays directly to objects which absorb the radiation- people, floors, machinery and other plant equipment. All these objects in turn re-radiate the energy to the air. A key element in the Panelbloc design is a coating applied to the aluminized steel outer surface of the heater. This coating must be corrosion resistant at high temperatures and it must have high "emissivity"-the ability of a surface to emit radiant energy. The Bettcher company formerly used a porcelain coating, but it caused a production problem. Bettcher did not have the capability to apply the material in its own plant, so the heaters had to be shipped out of state for porcelainizing, which entailed extra cost. Bettcher sought a coating which could meet the specifications yet be applied in its own facilities. The company asked The Knowledge Availability Systems Center, Pittsburgh, Pennsylvania, a NASA Industrial Applications Center (IAC), for a search of NASA's files

  1. Highly Efficient Spin-to-Charge Current Conversion in Strained HgTe Surface States Protected by a HgCdTe Layer (United States)

    Noel, P.; Thomas, C.; Fu, Y.; Vila, L.; Haas, B.; Jouneau, P.-H.; Gambarelli, S.; Meunier, T.; Ballet, P.; Attané, J. P.


    We report the observation of spin-to-charge current conversion in strained mercury telluride at room temperature, using spin pumping experiments. We show that a HgCdTe barrier can be used to protect the HgTe from direct contact with the ferromagnet, leading to very high conversion rates, with inverse Edelstein lengths up to 2.0 ±0.5 nm . The influence of the HgTe layer thickness on the conversion efficiency is found to differ strongly from what is expected in spin Hall effect systems. These measurements, associated with the temperature dependence of the resistivity, suggest that these high conversion rates are due to the spin momentum locking property of HgTe surface states.

  2. Next generation HgCdTe FPAs for high frame rate characterization of thermal protective systems, Phase I (United States)

    National Aeronautics and Space Administration — Typical existing infrared (IR) focal plane arrays (FPAs) have high spatial resolution over large areas due to their high pixel counts, however they can only...

  3. Fast Surface Temperature Measurement of Teflon Propellant in Pulsed Ablative Discharges Using HgCdTe Photovoltaic Cells (PREPRINT)

    National Research Council Canada - National Science Library

    Antonsen, Erik L; Burton, Rodney L; Reed, Garrett A; Spanjers, Gregory G


    ... ablative discharge with Teflon(TradeMark) as the ablated material. Analysis is used to derive a governing equation for detector output voltage for materials with wavelength dependent emissivity...

  4. Correlation of Etch Pits and Dislocations in As-grown and Thermal Cycle-Annealed HgCdTe(211) Films (United States)

    Vaghayenegar, M.; Jacobs, R. N.; Benson, J. D.; Stoltz, A. J.; Almeida, L. A.; Smith, David J.


    This paper reports observations of the different types of etch pits and dislocations present in thick HgCdTe (211) layers grown by molecular beam epitaxy on CdTe/Si (211) composite substrates. Dislocation analysis for as-grown and thermal cycle-annealed samples has been carried out using bright-field transmission electron microscopy. Triangular pits present in as-grown material are associated with a mixture of Frank partials and perfect dislocations, while pits with fish-eye shapes have perfect dislocations with 1/2[0\\bar{1}1] Burgers vector. The dislocations beneath skew pits are more complex as they have two different crystallographic directions, and are associated with a mixture of Shockley partials and perfect dislocations. Dislocation analysis of samples after thermal cycle annealing (TCA) shows that the majority of dislocations under the etch pits are short segments of perfect dislocations with 1/2[0\\bar{1}1] Burgers vector while the remainder are Shockley partials. The absence of fish-eye shape pits in TCA samples suggests that they are associated with mobile dislocations that have reacted during annealing, causing the overall etch pit density to be reduced. Very large pits with a density ˜2×103 cm-2 are observed in as-grown and TCA samples. These defects thread from within the CdTe buffer layer into the upper regions of the HgCdTe layers. Their depth in as-grown material is so large that it is not possible to locate and identify the underlying defects.

  5. Smoke detectors

    International Nuclear Information System (INIS)

    Fung, C.K.


    This describes a smoke detector comprising a self-luminous light source and a photosensitive device which is so arranged that the light source is changed by the presence of smoke in a detecting region. A gaseous tritium light source is used. This consists of a borosilicate glass bulb with an internal phosphor coating, filled with tritium gas. The tritium emits low energy beta particles which cause the phosphor to glow. This is a reliable light source which needs no external power source. The photosensitive device may be a phototransistor and may drive a warning device through a directly coupled transistor amplifier. (U.K.)

  6. Radiation detector

    International Nuclear Information System (INIS)

    Conrad, B.; Finkenzeller, J.; Kiiehn, G.; Lichtenberg, W.


    In an exemplary embodiment, a flat radiation beam is detected having a common electrode disposed parallel to the beam plane at one side and a common support with a series of individual conductors providing electrodes opposite successive portions of the common electrode and lying in a plane also parallel to the beam plane. The beam may be fan-shaped and the individual electrodes may be aligned with respective ray paths separated by uniform angular increments in the beam plane. The individual conductors and the connection thereof to the exterior of the detector housing may be formed on an insulator which can be folded into a T-shape for leading the supply conductors for alternate individual conductors toward terminals at opposite sides of the chamber

  7. Particle detectors

    CERN Document Server

    Hilke, Hans Jürgen; Joram, Christian; CERN. Geneva


    Lecture 5: Detector characteristics: ALEPH Experiment cut through the devices and events - Discuss the principles of the main techniques applied to particle detection ( including front-end electronics), the construction and performance of some of the devices presently in operartion and a few ideas on the future performance. Lecture 4-pt. b Following the Scintillators. Lecture 4-pt. a : Scintillators - Used for: -Timing (TOF, Trigger) - Energy Measurement (Calorimeters) - Tracking (Fibres) Basic scintillation processes- Inorganic Scintillators - Organic Scintil - Discuss the principles of the main techniques applied to particle detection ( including front-end electronics), the construction and performance of some of the devices presently in operation and a fiew ideas on future developpement session 3 - part. b Following Calorimeters lecture 3-pt. a Calorimeters - determine energy E by total absorption of charged or neutral particles - fraction of E is transformed into measurable quantities - try to acheive sig...

  8. Smoke detectors

    International Nuclear Information System (INIS)

    Bryant, J.


    An ionization smoke detector consisting of two electrodes defining an ionization chamber permitting entry of smoke, a radioactive source to ionize gas in the chamber and a potential difference applied across the first and second electrodes to cause an ion current to flow is described. The current is affected by entry of smoke. An auxiliary electrode is positioned in the ionization chamber between the first and second electrodes, and it is arranged to maintain or create a potential difference between the first electrode and the auxiliary electrode. The auxiliary electrode may be used for testing or for adjustment of sensitivity. A collector electrode divides the chamber into two regions with the auxiliary electrode in the outer sensing region. (U.K.)

  9. Ionization detector

    International Nuclear Information System (INIS)

    Solomon, E.E.


    A safe and reliable apparatus for detecting products of combustion and aerosols in the atmosphere was developed which uses a beta source. It is easy to adjust for optimum performance. The ionization detector comprises a double chamber; one of the chambers is the basic sensing chamber. The sensing chamber is ported to both the secondary chambers to account for slow ambient changes in the atmosphere outside of the chamber. The voltages from the ionization chamber are adjusted with electrodes in each chamber. The ionization chamber contains baffles to direct the air to be sensed as well as an electrostatic screen. A unique electronic circuit provides an inexpensive and reliable means for detecting the signal change which occurs in the ionization chamber. The decision level of the alarm circuit can be adjusted to allow for any desired sensitivity. (D.N.)

  10. Silicon radiation detectors

    International Nuclear Information System (INIS)

    Lutz, G.


    An introduction to and an overview of function principles and properties of semiconductor radiation detectors is attempted. The paper is addressed to people interested in detector development but not already experts in the field of semiconductor detectors. (orig.)

  11. Novel mid-infrared imaging system based on single-mode quantum cascade laser illumination and upconversion

    DEFF Research Database (Denmark)

    Tomko, Jan; Junaid, Saher; Tidemand-Lichtenberg, Peter


    Compared to the visible or near-infrared (NIR) spectral regions, there is a lack of very high sensitivity detectors in the mid-infrared (MIR) that operate near room temperature. Upconversion of the MIR light to NIR light that is imaged using affordable, fast, and sensitive NIR detectors or camera...

  12. Research on cloud background infrared radiation simulation based on fractal and statistical data (United States)

    Liu, Xingrun; Xu, Qingshan; Li, Xia; Wu, Kaifeng; Dong, Yanbing


    Cloud is an important natural phenomenon, and its radiation causes serious interference to infrared detector. Based on fractal and statistical data, a method is proposed to realize cloud background simulation, and cloud infrared radiation data field is assigned using satellite radiation data of cloud. A cloud infrared radiation simulation model is established using matlab, and it can generate cloud background infrared images for different cloud types (low cloud, middle cloud, and high cloud) in different months, bands and sensor zenith angles.

  13. Calibration of detector efficiency of neutron detector

    International Nuclear Information System (INIS)

    Guo Hongsheng; He Xijun; Xu Rongkun; Peng Taiping


    BF 3 neutron detector has been set up. Detector efficiency is calibrated by associated particle technique. It is about 3.17 x 10 -4 (1 +- 18%). Neutron yield of neutron generator per pulse (10 7 /pulse) is measured by using the detector

  14. Systems engineering and analysis of electro-optical and infrared systems

    CERN Document Server

    Arrasmith, William Wolfgang


    Introduction to Electro-optic and Infrared (EO/IR) Systems Engineering?Radiation in the Visible and Infrared Parts of the Electromagnetic SpectrumRadiation SourcesThe Effect of the Atmosphere on Optical PropagationBasic OpticsOptical ModulationThe Detection of Optical RadiationNoise in the Optical Detection ProcessTechnical Performance Measures and Metrics of Optical DetectorsModern Detectors and their Measures of PerformanceThe Effects of Cooling on Optical Detector NoiseSignal and Image ProcessingElectro-Optic and Infrared Systems AnalysisLaser Imaging Systems?Spectral Imaging?LIDAR and LADA

  15. Position detector

    International Nuclear Information System (INIS)

    Hayakawa, Toshifumi.


    Purpose: To enable to detect the position of an moving object in a control rod position detector, stably in a digital manner at a high accuracy and free from the undesired effects of circumstantial conditions such as the reactor temperature. Constitution: Coils connected in parallel with each other are disposed along the passage of a moving object and variable resistors and relays are connected in series with each of the coils respectively. Light emitting diodes is connected in series with the contacts of the respective relays. The resistance value of the variable resistors are adjusted depending on the changes in the circumstantial conditions and temperature distribution upon carrying out the positional detection. When the object is inserted into a coils, the relevant relay is deenergized, by which the relay contacts are closed to light up the diode. In the same manner, as the object is successively inserted into the coils, the diodes are lighted-up successively thereby enabling highly accurate and stable positional detection in a digital manner, free from the undesired effects of the circumstantial conditions. (Horiuchi, T.)


    CERN Multimedia

    F. Gasparini

    DT As announced in the previous Bulletin MU DT completed the installation of the vertical chambers of barrel wheels 0, +1 and +2. 242 DT and RPC stations are now installed in the negative barrel wheels. The missing 8 (4 in YB-1 and 4 in YB-2) chambers can be installed only after the lowering of the two wheels into the UX cavern, which is planned for the last quarter of the year. Cabling on the surface of the negative wheels was finished in May after some difficulties with RPC cables. The next step was to begin the final commissioning of the wheels with the final trigger and readout electronics. Priority was giv¬en to YB0 in order to check everything before the chambers were covered by cables and services of the inner detectors. Commissioning is not easy since it requires both activity on the central and positive wheels underground, as well as on the negative wheels still on the surface. The DT community is requested to commission the negative wheels on surface to cope with a possible lack of time a...

  17. Semiconductor high-energy radiation scintillation detector

    International Nuclear Information System (INIS)

    Kastalsky, A.; Luryi, S.; Spivak, B.


    We propose a new scintillation-type detector in which high-energy radiation generates electron-hole pairs in a direct-gap semiconductor material that subsequently recombine producing infrared light to be registered by a photo-detector. The key issue is how to make the semiconductor essentially transparent to its own infrared light, so that photons generated deep inside the semiconductor could reach its surface without tangible attenuation. We discuss two ways to accomplish this, one based on doping the semiconductor with shallow impurities of one polarity type, preferably donors, the other by heterostructure bandgap engineering. The proposed semiconductor scintillator combines the best properties of currently existing radiation detectors and can be used for both simple radiation monitoring, like a Geiger counter, and for high-resolution spectrography of the high-energy radiation. An important advantage of the proposed detector is its fast response time, about 1 ns, essentially limited only by the recombination time of minority carriers. Notably, the fast response comes without any degradation in brightness. When the scintillator is implemented in a qualified semiconductor material (such as InP or GaAs), the photo-detector and associated circuits can be epitaxially integrated on the scintillator slab and the structure can be stacked-up to achieve virtually any desired absorption capability

  18. Uncooled infrared photodetectors in Poland (United States)

    Piotrowski, J.; Piotrowski, A.


    The history and present status of the middle and long wavelength Hg1-xCdxTe infrared detectors in Poland are reviewed. Research and development efforts in Poland were concentrated mostly on uncooled market niche. Technology of the infrared photodetectors has been developed by several research groups. The devices are based on mercury-based variable band gap semiconductor alloys. Modified isothermal vapour phase epitaxy (ISOVPE) has been used for many years for research and commercial fabrication of photoconductive, photoelectromagnetic and other devices. Bulk growth and liquid phase epitaxy was also used. At present, the fabrication of IR devices relies on low temperature epitaxial technique, namely metalorganic vapour phase deposition (MOCVD), frequently in combination with the ISOVPE. Photoconductive and photoelectromagnetic detectors are still in production. The devices are gradually replaced with photovoltaic devices which offer inherent advantages of no electric or magnetic bias, no heat load and no flicker noise. Potentially, the PV devices could offer high performance and very fast response. At present, the uncooled long wavelength devices of conventional design suffer from two issues; namely low quantum efficiency and very low junction resistance. It makes them useless for practical applications. The problems have been solved with advanced 3D band gap engineered architecture, multiple cell heterojunction devices connected in series, monolithic integration of the detectors with microoptics and other improvements. Present fabrication program includes devices which are optimized for operation at any wavelength within a wide spectral range 1-15 μm and 200-300 K temperature range. Special solutions have been applied to improve speed of response. Some devices show picoseconds range response time. The devices have found numerous civilian and military applications.

  19. A Novel Infrared Gas Monitor (United States)

    Wang, Yingding; Zhong, Hongjie


    In the paper a novel non-dispersive infrared(IR) gas monitor is described.It is based on the principle that certain gases absorb IR radiation at specific(and often unique) wavelengths.Conventional devices typically include several primary components:a broadband source, usually an incandescent filament,a rotating chopper shutter,a narrow-band filter,a sample tube and a detector. We have developed a number of IR light emitting diodes(LED) having narrow optical bandwidths and which can be intensity modulated by electrical means,for example InAsSbP(4.2 micron)LED.The IR LED can thus replace the thermal source,narrow-band filter and chopper assembly of the conventional IR gas monitor,yielding a solid state,low- powered,compact and almost maintenance-free instrument with high sensitivity and stability and which free of the effects of mechanical vibration too. The detector used in the IR gas monitor is the solid-state detector,such as PbS,PbSe, InSb,HgCdTe,TGS,LT and PZT detector etc. The different configuration of the IR gas monitor is designed.For example,two-path version for measuring methane concentration by monitoring the 3.31 micron absorption band,it can eliminate the interference effects,such as to compensate for LED intensity changes caused by power and temperature variations,and for signal fluctuations due to changes in detector bias. we also have designed portable single-beam version without the sample tube.Its most primary advantage is very cheap(about cost USD 30 ).It measures carbon dioxide concentration by monitoring the 4.25 micron absorption band.Thought its precisions is low,it is used to control carbon dioxide concentration in the air in the green houses and plastic houses(there are about twenty millon one in the China).Because more carbon dioxide will increase the quanity of vegetable and flower production to a greatextent. It also is used in medical,sanitary and antiepidemic applications,such as hospital, store,hotel,cabin and ballroom etc. Key words:infrared

  20. Detector simulation needs for detector designers

    International Nuclear Information System (INIS)

    Hanson, G.G.


    Computer simulation of the components of SSC detectors and of the complete detectors will be very important for the designs of the detectors. The ratio of events from interesting physics to events from background processes is very low, so detailed understanding of detector response to the backgrounds is needed. Any large detector for the SSC will be very complex and expensive and every effort must be made to design detectors which will have excellent performance and will not have to undergo major rebuilding. Some areas in which computer simulation is particularly needed are pattern recognition in tracking detectors and development of shower simulation code which can be trusted as an aid in the design and optimization of calorimeters, including their electron identification performance. Existing codes require too much computer time to be practical and need to be compared with test beam data at energies of several hundred GeV. Computer simulation of the processing of the data, including electronics response to the signals from the detector components, processing of the data by microprocessors on the detector, the trigger, and data acquisition will be required. In this report we discuss the detector simulation needs for detector designers

  1. Infrared finiteness in Yang--Mills theories

    International Nuclear Information System (INIS)

    Appelquist, T.; Carazzone, J.; Kluberg-Stern, H.; Roth, M.


    The infrared divergences of renormalizable theories with coupled massless fields (in particular, the Yang--Mills theory) are shown to cancel for transition probabilities corresponding to finite-energy-resolution detectors, just as in quantum electrodynamics. This result is established through lowest nontrivial order in perturbation theory for the detection of massive muons in a quantum electrodynamic theory containing massless electrons or the detection of massive quarks in a Yang--Mills theory

  2. The GRANDE detector

    International Nuclear Information System (INIS)

    Adams, A.; Bond, R.; Coleman, L.; Rollefson, A.; Wold, D.; Bratton, C.B.; Gurr, H.; Kropp, W.; Nelson, M.; Price, L.R.; Reines, F.; Schultz, J.; Sobel, H.; Svoboda, R.; Yodh, G.; Burnett, T.; Chaloupka, V.; Wilkes, R.J.; Cherry, M.; Ellison, S.B.; Guzik, T.G.; Wefel, J.; Gaidos, J.; Loeffler, F.; Sembroski, G.; Wilson, C.; Goodman, J.; Haines, T.J.; Kielczewska, D.; Lane, C.; Steinberg, R.; Lieber, M.; Nagle, D.; Potter, M.; Tripp, R.


    In this paper we present a detector facility which meets the requirements outlined above for a next-generation instrument. GRANDE (Gamma Ray and Neutrino DEtector) is an imaging, water Cerenkov detector, which combines in one facility an extensive air shower array and a high-energy neutrino detector. (orig.)

  3. Spiral silicon drift detectors

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.; Longoni, A.; Sampietro, M.; Holl, P.; Lutz, G.; Kemmer, J.; Prechtel, U.; Ziemann, T.


    An advanced large area silicon photodiode (and x-ray detector), called Spiral Drift Detector, was designed, produced and tested. The Spiral Detector belongs to the family of silicon drift detectors and is an improvement of the well known Cylindrical Drift Detector. In both detectors, signal electrons created in silicon by fast charged particles or photons are drifting toward a practically point-like collection anode. The capacitance of the anode is therefore kept at the minimum (0.1pF). The concentric rings of the cylindrical detector are replaced by a continuous spiral in the new detector. The spiral geometry detector design leads to a decrease of the detector leakage current. In the spiral detector all electrons generated at the silicon-silicon oxide interface are collected on a guard sink rather than contributing to the detector leakage current. The decrease of the leakage current reduces the parallel noise of the detector. This decrease of the leakage current and the very small capacities of the detector anode with a capacitively matched preamplifier may improve the energy resolution of Spiral Drift Detectors operating at room temperature down to about 50 electrons rms. This resolution is in the range attainable at present only by cooled semiconductor detectors. 5 refs., 10 figs

  4. An efficient shutter-less non-uniformity correction method for infrared focal plane arrays (United States)

    Huang, Xiyan; Sui, Xiubao; Zhao, Yao


    The non-uniformity response in infrared focal plane array (IRFPA) detectors has a bad effect on images with fixed pattern noise. At present, it is common to use shutter to prevent from radiation of target and to update the parameters of non-uniformity correction in the infrared imaging system. The use of shutter causes "freezing" image. And inevitably, there exists the problems of the instability and reliability of system, power consumption, and concealment of infrared detection. In this paper, we present an efficient shutter-less non-uniformity correction (NUC) method for infrared focal plane arrays. The infrared imaging system can use the data gaining in thermostat to calculate the incident infrared radiation by shell real-timely. And the primary output of detector except the shell radiation can be corrected by the gain coefficient. This method has been tested in real infrared imaging system, reaching high correction level, reducing fixed pattern noise, adapting wide temperature range.

  5. Solid state detector design

    International Nuclear Information System (INIS)

    Gunarwan Prayitno; Ahmad Rifai


    Much has been charged particle detector radiation detector made by the industry, especially those engaged in the development of detection equipment and components. The development and further research will be made solid state detector with silicon material. To be able to detect charged particles (radiation), required the processing of silicon material into the detector material. The method used to make silicon detector material is a lithium evaporations. Having formed an intrinsic region contactor installation process, and with testing. (author)

  6. WFC3 UVIS Detector Performance (United States)

    Gunning, Heather C.; Baggett, Sylvia M.; Gosmeyer, Catherine; Bourque, Matthew; MacKenty, John W.; Anderson, Jay; WFC3 Team


    The Wide Field Camera 3 (WFC3) is a fourth-generation imaging instrument installed on the Hubble Space Telescope (HST) during Servicing Mission 4 (SM4) in May 2000. WFC3 has two observational channels, UV/visible (UVIS) and infrared (IR); both have been performing well on-orbit. Since installation, the WFC3 team has been diligent in monitoring the performance of both detectors. The UVIS channel consists of two e2v, backside illuminated, 2Kx4K CCDs arranged in a 2x1 mosaic. We present results from some of the monitoring programs used to check various aspects of the UVIS detector. We discuss the growth trend of hot pixels and the efficacy of regular anneals in controlling the hot pixel population. We detail a pixel population with lowered-sensitivity that evolves during the time between anneals, and is largely reset by each anneal procedure. We discuss the stability of the post-flash LED lamp, used and recommended for CTE mitigation in observations with less than 12 e-/pixel backgrounds. Finally, we summarize long-term photometric trends of the UVIS detector, as well as the absolute gain measurement, used as a proxy for the on-orbit evolution of the UVIS channel.

  7. Topological insulator infrared pseudo-bolometer with polarization sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Peter Anand


    Topological insulators can be utilized in a new type of infrared photodetector that is intrinsically sensitive to the polarization of incident light and static magnetic fields. The detector isolates single topological insulator surfaces and allows light collection and exposure to static magnetic fields. The wavelength range of interest is between 750 nm and about 100 microns. This detector eliminates the need for external polarization selective optics. Polarization sensitive infrared photodetectors are useful for optoelectronics applications, such as light detection in environments with low visibility in the visible wavelength regime.

  8. ARNICA, the Arcetri near-infrared camera: Astronomical performance assessment. (United States)

    Hunt, L. K.; Lisi, F.; Testi, L.; Baffa, C.; Borelli, S.; Maiolino, R.; Moriondo, G.; Stanga, R. M.


    The Arcetri near-infrared camera ARNICA was built as a users' instrument for the Infrared Telescope at Gornergrat (TIRGO), and is based on a 256x256 NICMOS 3 detector. In this paper, we discuss ARNICA's optical and astronomical performance at the TIRGO and at the William Herschel Telescope on La Palma. Optical performance is evaluated in terms of plate scale, distortion, point spread function, and ghosting. Astronomical performance is characterized by camera efficiency, sensitivity, and spatial uniformity of the photometry.

  9. Multichannel far-infrared phase imaging for fusion plasmas

    International Nuclear Information System (INIS)

    Young, P.E.; Neikirk, D.P.; Tong, P.P.; Rutledge, D.B.; Luhmann, N.C. Jr.


    A 20-channel far-infrared imaging interferometer system has been used to obtain single-shot density profiles in the UCLA Microtor tokamak. This system differs from conventional multichannel interferometers in that the phase distribution produced by the plasma is imaged onto a single, monolithic, integrated microbolometer linear detector array and provides significantly more channels than previous far-infrared interferometers. The system has been demonstrated to provide diffraction-limited phase images of dielectric targets

  10. Compound Semiconductor Radiation Detector

    International Nuclear Information System (INIS)

    Kim, Y. K.; Park, S. H.; Lee, W. G.; Ha, J. H.


    In 1945, Van Heerden measured α, β and γ radiations with the cooled AgCl crystal. It was the first radiation measurement using the compound semiconductor detector. Since then the compound semiconductor has been extensively studied as radiation detector. Generally the radiation detector can be divided into the gas detector, the scintillator and the semiconductor detector. The semiconductor detector has good points comparing to other radiation detectors. Since the density of the semiconductor detector is higher than that of the gas detector, the semiconductor detector can be made with the compact size to measure the high energy radiation. In the scintillator, the radiation is measured with the two-step process. That is, the radiation is converted into the photons, which are changed into electrons by a photo-detector, inside the scintillator. However in the semiconductor radiation detector, the radiation is measured only with the one-step process. The electron-hole pairs are generated from the radiation interaction inside the semiconductor detector, and these electrons and charged ions are directly collected to get the signal. The energy resolution of the semiconductor detector is generally better than that of the scintillator. At present, the commonly used semiconductors as the radiation detector are Si and Ge. However, these semiconductor detectors have weak points. That is, one needs thick material to measure the high energy radiation because of the relatively low atomic number of the composite material. In Ge case, the dark current of the detector is large at room temperature because of the small band-gap energy. Recently the compound semiconductor detectors have been extensively studied to overcome these problems. In this paper, we will briefly summarize the recent research topics about the compound semiconductor detector. We will introduce the research activities of our group, too

  11. Microtextured Silicon Surfaces for Detectors, Sensors & Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Carey, JE; Mazur, E


    With support from this award we studied a novel silicon microtexturing process and its application in silicon-based infrared photodetectors. By irradiating the surface of a silicon wafer with intense femtosecond laser pulses in the presence of certain gases or liquids, the originally shiny, flat surface is transformed into a dark array of microstructures. The resulting microtextured surface has near-unity absorption from near-ultraviolet to infrared wavelengths well below the band gap. The high, broad absorption of microtextured silicon could enable the production of silicon-based photodiodes for use as inexpensive, room-temperature multi-spectral photodetectors. Such detectors would find use in numerous applications including environmental sensors, solar energy, and infrared imaging. The goals of this study were to learn about microtextured surfaces and then develop and test prototype silicon detectors for the visible and infrared. We were extremely successful in achieving our goals. During the first two years of this award, we learned a great deal about how microtextured surfaces form and what leads to their remarkable optical properties. We used this knowledge to build prototype detectors with high sensitivity in both the visible and in the near-infrared. We obtained room-temperature responsivities as high as 100 A/W at 1064 nm, two orders of magnitude higher than standard silicon photodiodes. For wavelengths below the band gap, we obtained responsivities as high as 50 mA/W at 1330 nm and 35 mA/W at 1550 nm, close to the responsivity of InGaAs photodiodes and five orders of magnitude higher than silicon devices in this wavelength region.

  12. Feldspar, Infrared Stimulated Luminescence

    DEFF Research Database (Denmark)

    Jain, Mayank


    This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars.......This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars....

  13. Lead salt resonant cavity enhanced detector with MEMS mirror (United States)

    Felder, F.; Fill, M.; Rahim, M.; Zogg, H.; Quack, N.; Blunier, S.; Dual, J.


    We describe a tunable resonant cavity enhanced detector (RCED) for the mid-infrared employing narrow gap lead-chalcogenide (IV-VI) layers on a Si substrate. The device consists of an epitaxial Bragg reflector layer, a thin p-n+ heterojunction with PbSrTe as detecting layer and a micro-electro-mechanical system (MEMS) micromirror as second mirror. Despite the thin absorber layer the sensitivity is even higher than for a conventional detector. Tunability is achieved by changing the cavity length with a vertically movable MEMS mirror. The device may be used as miniature infrared spectrometer to cover the spectral range from 30 μm.

  14. Extragalactic infrared astronomy

    International Nuclear Information System (INIS)

    Gondhalekar, P.M.


    The paper concerns the field of Extragalactic Infrared Astronomy, discussed at the Fourth RAL Workshop on Astronomy and Astrophysics. Fifteen papers were presented on infrared emission from extragalactic objects. Both ground-(and aircraft-) based and IRAS infrared data were reviewed. The topics covered star formation in galaxies, active galactic nuclei and cosmology. (U.K.)

  15. WISE: The Wide-field Infrared Survey Explorer (United States)

    Eisenhardt, Peter R.; Wright, E. L.; Benford, D.; Blain, A.; Cohen, M.; Cutri, R.; Gautier, T. N.; Jarrett, T.; Kirkpatrick, J. D.; Leisawitz, D.; Lonsdale, C.; Mainzer, A.; Mather, J.; McLean, I.; McMillan, R.; Mendez, B.; Padgett, D.; Ressler, M.; Skrutskie, M.; Stanford, S. A.; Walker, R.


    WISE will map the entire sky at 3.3, 4.7, 12 and 23 microns with sensitivities of 0.12, 0.16. 0.65, and 2.6 mJy. WISE will find the most luminous galaxies in the universe, the closest stars to the Sun, and detect most main belt asteroids larger than 3 km. WISE will be placed into a Sun-synchronous polar orbit on a Delta 7320-10 rocket, rotating at a constant rate while a scan mirror freezes the line of sight during each exposure, covering the sky in 6 months following a one month checkout. Orbit to orbit overlap provides 8 or more exposures at each location. The instrument, provided by the Space Dynamics Laboratory, includes an all-reflective aluminum telescope with a 40 cm primary built by SSG-Tinsley, a solid hydrogen cryostat built by Lockheed-Martin's Advanced Technology Center, and 1024x1024 pixel Si:As and HgCdTe arrays built by DRS and Teledyne. Dichroic beamsplitters allow simultaneous images in the four bands over a 47'x47' field of view with 5" resolution to be obtained every 11 seconds. Ball Aerospace is providing the spacecraft, including a 500W fixed solar array, Li-ion battery, two star trackers, reaction wheels, and torque rods. The 50 GB per day of images are losslessly compressed, stored in flash memory, and downlinked at 100 Mbps four times per day using a fixed antenna and TDRSS satellites. The Infrared Processing and Analysis Center will process the data and deliver the image atlas and source catalog, with a preliminary release 6 months after the survey, and a final release 2 years after the survey. JPL manages the project for UCLA PI Ned Wright, and conducts mission operations. Education and Public Outreach is provided by UC Berkeley's Space Science Laboratory. WISE hardware is presently being integrated and tested, with launch scheduled in November 2009.

  16. The Martian Oasis Detector (United States)

    Smith, P. H.; tomasko, M. G.; McEwen, A.; Rice, J.


    public and Congress providing an attainable goal for both robotic and manned missions. The instrument required to detect an active oasis is a high spatial resolution (few tens of meters) Short Wavelength Infrared (SWIR) spectrometer coupled with a high resolution camera (five m/pixel). This combination creates too large a data volume to possibly return data for the entire Martian Surface; therefore it has been designed as one of the first in a new generation of 'smart' detectors, called the Mars Oasis Detector (MOD).

  17. Drift Chambers detectors; Detectores de deriva

    Energy Technology Data Exchange (ETDEWEB)

    Duran, I; Martinez laso, L


    We present here a review of High Energy Physics detectors based on drift chambers. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysed, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author) 115 refs.

  18. Mica fission detectors

    International Nuclear Information System (INIS)

    Wong, C.; Anderson, J.D.; Hansen, L.; Lehn, A.V.; Williamson, M.A.


    The present development status of the mica fission detectors is summarized. It is concluded that the techniques have been refined and developed to a state such that the mica fission counters are a reliable and reproducible detector for fission events

  19. Simulating detectors dead time

    International Nuclear Information System (INIS)

    Rustom, Ibrahim Farog Ibrahim


    Nuclear detectors are used in all aspects of nuclear measurements. All nuclear detectors are characterized by their dead time i.e. the time needed by a detector to recover from a previous incident. A detector dead time influences measurements taken by a detector and specially when measuring high decay rate (>) where is the detector dead time. Two models are usually used to correct for the dead time effect: the paralayzable and the non-paralayzable models. In the current work we use Monte Carlo simulation techniques to simulate radioactivity and the effect of dead time and the count rate of a detector with a dead time =5x10 - 5s assuming the non-paralayzable model. The simulation indicates that assuming a non -paralayzable model could be used to correct for decay rate measured by a detector. The reliability of the non-paralayzable model to correct the measured decay rate could be gauged using the Monte Carlo simulation. (Author)

  20. Forward tracking detectors

    Indian Academy of Sciences (India)

    Abstract. Forward tracking is an essential part of a detector at the international linear collider (ILC). The requirements for forward tracking are explained and the proposed solutions in the detector concepts are shown.

  1. Type II superlattice technology for LWIR detectors (United States)

    Klipstein, P. C.; Avnon, E.; Azulai, D.; Benny, Y.; Fraenkel, R.; Glozman, A.; Hojman, E.; Klin, O.; Krasovitsky, L.; Langof, L.; Lukomsky, I.; Nitzani, M.; Shtrichman, I.; Rappaport, N.; Snapi, N.; Weiss, E.; Tuito, A.


    SCD has developed a range of advanced infrared detectors based on III-V semiconductor heterostructures grown on GaSb. The XBn/XBp family of barrier detectors enables diffusion limited dark currents, comparable with MCT Rule-07, and high quantum efficiencies. This work describes some of the technical challenges that were overcome, and the ultimate performance that was finally achieved, for SCD's new 15 μm pitch "Pelican-D LW" type II superlattice (T2SL) XBp array detector. This detector is the first of SCD's line of high performance two dimensional arrays working in the LWIR spectral range, and was designed with a ~9.3 micron cut-off wavelength and a format of 640 x 512 pixels. It contains InAs/GaSb and InAs/AlSb T2SLs, engineered using k • p modeling of the energy bands and photo-response. The wafers are grown by molecular beam epitaxy and are fabricated into Focal Plane Array (FPA) detectors using standard FPA processes, including wet and dry etching, indium bump hybridization, under-fill, and back-side polishing. The FPA has a quantum efficiency of nearly 50%, and operates at 77 K and F/2.7 with background limited performance. The pixel operability of the FPA is above 99% and it exhibits a stable residual non uniformity (RNU) of better than 0.04% of the dynamic range. The FPA uses a new digital read-out integrated circuit (ROIC), and the complete detector closely follows the interfaces of SCD's MWIR Pelican-D detector. The Pelican- D LW detector is now in the final stages of qualification and transfer to production, with first prototypes already integrated into new electro-optical systems.

  2. HIBP primary beam detector

    International Nuclear Information System (INIS)

    Schmidt, T.W.


    A position measuring detector was fabricated for the Heavy Ion Beam Probe. The 11 cm by 50 cm detector was a combination of 15 detector wires in one direction and 63 copper bars - .635 cm by 10 cm to measure along an orthogonal axis by means of a current divider circuit. High transmission tungsten meshes provide entrance windows and suppress secondary electrons. The detector dimensions were chosen to resolve the beam position to within one beam diameter

  3. The OSMOND detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Dalgliesh, R. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Duxbury, D.M., E-mail: [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Helsby, W.I. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Holt, S.A.; Kinane, C.J. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Marsh, A.S. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire, OX11 0DE (United Kingdom); Rhodes, N.J.; Schooneveld, E.M. [ISIS Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom); Spill, E.J.; Stephenson, R. [Technology Dept. Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Oxfordshire, OX11 0QX (United Kingdom)


    The development and testing of the Off Specular MicrOstrip Neutron Detector (OSMOND) is described. Based on a microstrip gas chamber the aim of the project was to produce a high counting rate detector capable of replacing the existing rate limited scintillator detectors currently in use on the CRISP reflectometer for off specular reflectometry experiments. The detector system is described together with results of neutron beam tests carried out at the ISIS spallation neutron source.

  4. Ultrafast stimulated Raman spectroscopy in the near-infrared region

    International Nuclear Information System (INIS)

    Takaya, Tomohisa


    A number of electronic transitions in the near-infrared wavelength region are associated with migration or delocalization of electrons in large molecules or molecular systems. Time-resolved near-infrared Raman spectroscopy will be a powerful tool for investigating the structural dynamic of samples with delocalized electrons. However, the sensitivity of near-infrared spontaneous Raman spectrometers is significantly low due to an extremely small probability of Raman scattering and a low sensitivity of near-infrared detectors. Nonlinear Raman spectroscopy is one of the techniques that can overcome the sensitivity problems and enable us to obtain time-resolved Raman spectra in resonance with near-IR transitions. In this article, the author introduces recent progress of ultrafast time-resolved near-infrared stimulated Raman spectroscopy. Optical setup, spectral and temporal resolution, and applications of the spectrometer are described. (author)

  5. Influence Of Nonuniformity On Infrared Focal Plane Array Performance (United States)

    Milton, A. F.; Barone, F. R.; Kruer, M. R.


    It is well known that detector response nonuniformity results in pattern noise with staring sensors that is a severe problem in the infrared due to the low intrinsic contrast of IR imagery. The pattern noise can be corrected by electronic processing; however, the ability to correct for pattern noise is limited by the interaction of interscene and intrascene variability with the dynamic range of the processor (number of bits) and, depending upon the algorithm used, by nonlinearities in the detector response. This paper quantifies these limitations and describes the interaction of detector gain nonuniformity and detector nonlinearities. Probabilistic models are developed to determine the maximum sensitivity that can be obtained using a two-point algorithm to correct a nonlinear response curve over a wide temperature range. Curves that permit a prediction of the noise equivalent differential temperature (NEAT) under varying circumstances are presented. A piecewise linear approach to dealing with severe detector response nonlinearities is presented and analyzed for its effectiveness.

  6. WORKSHOP: Scintillating fibre detectors

    International Nuclear Information System (INIS)



    Scintillating fibre detector development and technology for the proposed US Superconducting Supercollider, SSC, was the subject of a recent workshop at Fermilab, with participation from the high energy physics community and from industry. Sessions covered the current status of fibre technology and fibre detectors, new detector applications, fluorescent materials and scintillation compositions, radiation damage effects, amplification and imaging structures, and scintillation fibre fabrication techniques

  7. Shielded regenerative neutron detector

    International Nuclear Information System (INIS)

    Terhune, J.H.; Neissel, J.P.


    An ion chamber type neutron detector is disclosed which has a greatly extended lifespan. The detector includes a fission chamber containing a mixture of active and breeding material and a neutron shielding material. The breeding and shielding materials are selected to have similar or substantially matching neutron capture cross-sections so that their individual effects on increased detector life are mutually enhanced

  8. The CAPRICE RICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Basini, G. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Codino, A.; Grimani, C. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica]|[INFN, Sezione Univ. `Tor Vergata` Rome (Italy); Cafagna, F. [Bari Univ. (Italy)]|[INFN, Bari (Italy); Golden, R.L. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Brancaccio, F.; Bocciolini, M. [Florence Univ. (Italy)]|[INFN, Florence (Italy); Barbiellini, G.; Boezio, M. [Trieste Univ. (Italy)]|[INFN, Trieste (Italy)


    A compact RICH detector has been developed and used for particle identification in a balloon borne spectrometer to measure the flux of antimatter in the cosmic radiation. This is the first RICH detector ever used in space experiments that is capable of detecting unit charged particles, such as antiprotons. The RICH and all other detectors performed well during the 27 hours long flight.

  9. Self powered neutron detectors

    International Nuclear Information System (INIS)

    Gopalan, C.S.; Ramachandra Rao, M.N.; Ingale, A.D.


    Two types of self powered neutron detectors used for in-core flux measurements are described. The characteristics of the various detectors, with emitters Rh, V, Co, Py are presented. Details about the fabrication of these detectors are given. (A.K.)

  10. The JADE muon detector

    International Nuclear Information System (INIS)

    Allison, J.; Armitage, J.C.M.; Baines, J.T.M.; Ball, A.H.; Bamford, G.; Barlow, R.J.; Bowdery, C.K.; Chrin, J.T.M.; Duerdoth, I.P.; Glendinning, I.; Greenshaw, T.; Hassard, J.F.; Hill, P.; King, B.T.; Loebinger, F.K.; Macbeth, A.A.; McCann, H.; Mercer, D.; Mills, H.E.; Murphy, P.G.; Prosper, H.B.; Rowe, P.; Stephens, K.


    The JADE muon detector consists of 618 planar drift chambers interspersed between layers of hadron absorber. This paper gives a detailed description of the construction and operation of the detector as a whole and discusses the properties of the drift chambers. The muon detector has been operating successfully at PETRA for five years. (orig.)

  11. Economical stabilized scintillation detector

    International Nuclear Information System (INIS)

    Anshakov, O.M.; Chudakov, V.A.; Gurinovich, V.I.


    An economical scintillation detector with the stabilization system of an integral type is described. Power consumed by the photomultiplier high-voltage power source is 40 mW, energy resolution is not worse than 9%. The given detector is used in a reference detector of a digital radioisotope densimeter for light media which is successfully operating for several years

  12. Gas filled detectors

    International Nuclear Information System (INIS)

    Stephan, C.


    The main types of gas filled nuclear detectors: ionization chambers, proportional counters, parallel-plate avalanche counters (PPAC) and microstrip detectors are described. New devices are shown. A description of the processes involved in such detectors is also given. (K.A.) 123 refs.; 25 figs.; 3 tabs

  13. HP Ge planar detectors

    International Nuclear Information System (INIS)

    Gornov, M.G.; Gurov, Yu.B.; Soldatov, A.M.; Osipenko, B.P.; Yurkowski, J.; Podkopaev, O.I.


    Parameters of planar detectors manufactured of HP Ge are presented. The possibilities to use multilayer spectrometers on the base of such semiconductor detectors for nuclear physics experiments are discussed. It is shown that the obtained detectors including high square ones have spectrometrical characteristics close to limiting possible values. 9 refs.; 3 figs.; 1 tab

  14. New Generation of Superconducting Nanowire Single-Photon Detectors

    Directory of Open Access Journals (Sweden)

    Goltsman G.N.


    Full Text Available We present an overview of recent results for new generation of infrared and optical superconducting nanowire single-photon detectors (SNSPDs that has already demonstrated a performance that makes them devices-of-choice for many applications. SNSPDs provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, SNSPDs are also compatible with an integrated optical platform as a crucial requirement for applications in emerging quantum photonic technologies. By embedding SNSPDs in nanophotonic circuits we realize waveguide integrated single photon detectors which unite all desirable detector properties in a single device.

  15. Infrared microspectroscopy with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Carr, G.L.; Williams, G.P. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source


    Infrared microspectroscopy with a high brightness synchrotron source can achieve a spatial resolution approaching the diffraction limit. However, in order to realize this intrinsic source brightness at the specimen location, some care must be taken in designing the optical system. Also, when operating in diffraction limited conditions, the effective spatial resolution is no longer controlled by the apertures typically used for a conventional (geometrically defined) measurement. Instead, the spatial resolution depends on the wavelength of light and the effective apertures of the microscope`s Schwarzchild objectives. The authors have modeled the optical system from the synchrotron source up to the sample location and determined the diffraction-limited spatial distribution of light. Effects due to the dependence of the synchrotron source`s numerical aperture on wavelength, as well as the difference between transmission and reflection measurement modes, are also addressed. Lastly, they examine the benefits (when using a high brightness source) of an extrinsic germanium photoconductive detector with cone optics as a replacement for the standard MCT detector.

  16. Mid infrared MEMS FTIR spectrometer (United States)

    Erfan, Mazen; Sabry, Yasser M.; Mortada, Bassem; Sharaf, Khaled; Khalil, Diaa


    In this work we report, for the first time to the best of our knowledge, a bulk-micromachined wideband MEMS-based spectrometer covering both the NIR and the MIR ranges and working from 1200 nm to 4800 nm. The core engine of the spectrometer is a scanning Michelson interferometer micro-fabricated using deep reactive ion etching (DRIE) technology. The spectrum is obtained using the Fourier Transform techniques that allows covering a very wide spectral range limited by the detector responsivity. The moving mirror of the interferometer is driven by a relatively large stroke electrostatic comb-drive actuator. Zirconium fluoride (ZrF4) multimode optical fibers are used to connect light between the white light source and the interferometer input, as well as the interferometer output to a PbSe photoconductive detector. The recorded signal-to-noise ratio is 25 dB at the wavelength of 3350 nm. The spectrometer is successfully used in measuring the absorption spectra of methylene chloride, quartz glass and polystyrene film. The presented solution provides a low cost method for producing miniaturized spectrometers in the near-/mid-infrared.

  17. The Far-Infrared Surveyor (FIS) for AKARI

    NARCIS (Netherlands)

    Kawada, Mitsunobu; Baba, Hajime; Barthel, Peter D.; Clements, David; Cohen, Martin; Doi, Yasuo; Figueredo, Elysandra; Fujiwara, Mikio; Goto, Tomotsugu; Hasegawa, Sunao; Hibi, Yasunori; Hirao, Takanori; Hiromoto, Norihisa; Jeong, Woong-Seob; Kaneda, Hidehiro; Kawai, Toshihide; Kawamura, Akiko; Kester, Do; Kii, Tsuneo; Kobayashi, Hisato; Kwon, Suk Minn; Lee, Hyung Mok; Makiuti, Sin'itirou; Matsuo, Hiroshi; Matsuura, Shuji; Mueller, Thomas G.; Murakami, Noriko; Nagata, Hirohisa; Nakagawa, Takao; Narita, Masanao; Noda, Manabu; Oh, Sang Hoon; Okada, Yoko; Okuda, Haruyuki; Oliver, Sebastian; Ootsubo, Takafumi; Pak, Soojong; Park, Yong-Sun; Pearson, Chris P.; Rowan-Robinson, Michael; Saito, Toshinobu; Salama, Alberto; Sato, Shinji; Savage, Richard S.; Serjeant, Stephen; Shibai, Hiroshi; Shirahata, Mai; Sohn, Jungjoo; Suzuki, Toyoaki; Takagi, Toshinobu; Takahashi, Hidenori; Thomson, Matthew; Usui, Fumihiko; Verdugo, Eva; Watabe, Toyoki; White, Glenn J.; Wang, Lingyu; Yamamura, Issei; Yamauchi, Chisato; Yasuda, Akiko


    The Far-Infrared Surveyor (FIS) is one of two focal-plane instruments on the AKARI satellite. FIS has four photometric bands at 65, 90, 140, and 160 mu m, and uses two kinds of array detectors. The FIS arrays and optics are designed to sweep the sky with high spatial resolution and redundancy. The

  18. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.


    The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

  19. The ATLAS Pixel Detector

    CERN Document Server

    Huegging, Fabian


    The contruction of the ATLAS Pixel Detector which is the innermost layer of the ATLAS tracking system is prgressing well. Because the pixel detector will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability for all parts, combined with a low material budget. The final detector layout, new results from production modules and the status of assembly are presented.

  20. The charge collection in single side silicon microstrip detectors

    CERN Document Server

    Eremin, V V; Roe, S; Ruggiero, G; Weilhammer, Peter


    The transient current technique has been used to investigate signal formation in unirradiated silicon microstrip detectors, which are similar in geometry to those developed for the ATLAS experiment at LHC. Nanosecond pulsed infrared and red lasers were used to induce the signals under study. Two peculiarities in the detector performance were observed: an unexpectedly slow rise to the signal induced in a given strip when signals are injected opposite to the strip, and a long duration of the induced signal in comparison with the calculated drift time of charge carriers through the detector thickness - with a significant fraction of the charge being induced after charge carrier arrival. These major effects and details of the detector response for different positions of charge injection are discussed in the context of Ramo's theorem and compared with predictions arising from the more commonly studied phenomenon of signal formation in planar pad detectors.

  1. Temperature effects on radiation damage in plastic detectors

    International Nuclear Information System (INIS)

    Mendoza A, D.


    The objective of present work was to study the temperature effect on radiation damage registration in the structure of a Solid State Nuclear Track Detector of the type CR-39. In order to study the radiation damage as a function of irradiation temperature, sheets of CR-39 detectors were irradiated with electron beams, simulating the interaction of positive ions. CR-39 detectors were maintained at a constant temperature from room temperature up to 373 K during irradiation. Two techniques were used from analyzing changes in the detector structure: Electronic Paramagnetic Resonance (EPR) and Infrared Spectroscopy (IR). It was found by EPR analysis that the amount of free radicals decrease as irradiation temperature increases. The IR spectrums show yield of new functional group identified as an hydroxyl group (OH). A proposed model of interaction of radiation with CR-39 detectors is discussed. (Author)

  2. A DBN based anomaly targets detector for HSI (United States)

    Ma, Ning; Wang, Shaojun; Yu, Jinxiang; Peng, Yu


    Due to the assumption that Hyperspectral image (HSI) should conform to Gaussian distribution, traditional Mahalanobis distance-based anomaly targets detectors perform poor because the assumption may not always hold. In order to solve those problems, a deep learning based detector, Deep Belief Network(DBN) anomaly detector(DBN-AD), was proposed to fit the unknown distribution of HSI by energy modeling, the reconstruction errors of this encode-decode processing are used for discriminating the anomaly targets. Experiments are implemented on real and synthesized HSI dataset which collection by Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS). Comparing to classic anomaly detector, the proposed method shows better performance, it performs about 0.17 higher in Area Under ROC Curve (AUC) than that of Reed-Xiaoli detector(RXD) and Kernel-RXD (K-RXD).

  3. Analysis of periodically patterned metallic nanostructures for infrared absorber (United States)

    Peng, Sha; Yuan, Ying; Long, Huabao; Liu, Runhan; Wei, Dong; Zhang, Xinyu; Wang, Haiwei; Xie, Changsheng


    With rapid advancement of infrared detecting technology in both military and civil domains, the photo-electronic performances of near-infrared detectors have been widely concerned. Currently, near-infrared detectors demonstrate some problems such as low sensitivity, low detectivity, and relatively small array scale. The current studies show that surface plasmons (SPs) stimulated over the surface of metallic nanostructures by incident light can be used to break the diffraction limit and thus concentrate light into sub-wavelength scale, so as to indicate a method to develop a new type of infrared absorber or detector with very large array. In this paper, we present the design and characterization of periodically patterned metallic nanostructures that combine nanometer thickness aluminum film with silicon wafer. Numerical computations show that there are some valleys caused by surface plasmons in the reflection spectrum in the infrared region, and both red shift and blue shift of the reflection spectrum were observed through changing the nanostructural parameters such as angle α and diameters D. Moreover, the strong E-field intensity is located at the sharp corner of the nano-structures.

  4. Theory of deep level trap effects on generation-recombination noise in HgCdTe photoconductors

    International Nuclear Information System (INIS)

    Iverson, A.E.; Smith, D.L.


    We present a theory of the effect of deep level centers on the generation-recombination (g-r) noise and responsivity of an intrinsic photoconductor. The deep level centers can influence the g-r noise and responsivity in three main ways: (i) they can shorten the bulk carrier lifetime by Shockley--Read--Hall recombination; (ii) for some values of the capture cross sections, deep level densities, and temperature, the deep levels can trap a significant fraction of the photogenerated minority carriers. This trapping reduces the effective minority carrier mobility and diffusivity and thus reduces the effect of carrier sweep out on both g-r noise and responsivity; (iii) the deep level centers add a new thermal noise source, which results from fluctuations between bound and free carriers. The strength of this new noise source decreases with decreasing temperature at a slower rate than band-to-band thermal g-r noise. Calculations have been performed for a X = 0.21, n-type Hg/sub 1-x/Cd/sub x/Te photoconductor using the parameters of a commonly occurring deep level center in this material. We find that for typical operating conditions photoconductive detector performance begins to degrade as the deep level density begins to exceed 10 16 cm -3

  5. Thin film encapsulated 1D thermoelectric detector in an IR microspectrometer

    NARCIS (Netherlands)

    Wu, H.; Emadi, A.; De Graaf, G.; Wolffenbuttel, R.F.


    A thermopile-based detector array for use in a miniaturized Infrared (IR) spectrometer has been designed and fabricated using CMOS compatible MEMS technology. The emphasis is on the optimal of the detector array at the system level, while considering the thermal design, the dimensional constraints

  6. MSM optical detector on the basis of II-type ZnSe/ZnTe superlattice

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetzov, P. I., E-mail:; Averin, S. V., E-mail:; Zhitov, V. A.; Zakharov, L. Yu.; Kotov, V. M. [Russian Academy of Sciences, Kotel’nikov Institute of Radioengineering and Electronics (Fryazino Branch) (Russian Federation)


    On the basis of a type-II ZnSe/ZnTe superlattice, a MSM (metal—semiconductor–metal) photodetector is fabricated and investigated. The detector features low dark currents and a high sensitivity. The spectral characteristic of the detector provides the possibility of the selective detection of three separate spectral portions of visible and near-infrared radiation.

  7. Radiation detectors laboratory

    International Nuclear Information System (INIS)

    Ramirez J, F.J.


    The National Institute for Nuclear Research has established a Radiation detector laboratory that has the possibility of providing to the consultants on the handling and applications of the nuclear radiation detectors. It has special equipment to repair the radiation detectors used in spectroscopy as the hyper pure Germanium for gamma radiation and the Lithium-silica for X-rays. There are different facilities in the laboratory that can become useful for other institutions that use radiation detectors. This laboratory was created to satisfy consultant services, training and repairing of the radiation detectors both in national and regional levels for Latin America. The laboratory has the following sections: Nuclear Electronic Instrumentation; where there are all kind of instruments for the measurement and characterization of detectors like multichannel analyzers of pulse height, personal computers, amplifiers and nuclear pulse preamplifiers, nuclear pulses generator, aleatories, computer programs for radiation spectra analysis, etc. High vacuum; there is a vacuum escape measurer, two high vacuum pumps to restore the vacuum of detectors, so the corresponding measurers and the necessary tools. Detectors cleaning; there is an anaerobic chamber for the detectors handling at inert atmosphere, a smoke extraction bell for cleaning with the detector solvents. Cryogenic; there are vessels and tools for handling liquid nitrogen which is used for cooling the detectors when they required it. (Author)

  8. GeSn Based Near and Mid Infrared Heterostructure Detectors (United States)


    prestigious journals. 15.  SUBJECT TERMS Plasmonic Enhancement, Metal Nanostructures, CMOS, Photodetectors, Germanium-Tin Diode, IR Focal Plane Array...following features: (1) ease of manufacture in a foundry via a simple epitaxial structure, (2) end- fire coupling into on-chip transparent Ge or Si

  9. Monolithic Silicon Microbolometer Materials for Uncooled Infrared Detectors (United States)


    2012 11/03/2012 2.00 3.00 Mingliang Zhang, D. Drabold. Comparison of the Kubo formula, the microscopic response method, and the Greenwood formula...structure with four layers.................................................. 37 Figure 2-12. (a) Cartoon and (b) graph of TLM pattern used to calculate before and after annealing. This sample was used to calculate the average grain size and average stress. This film was prepared with 60 SCCM

  10. High-energy detector (United States)

    Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY


    The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

  11. Infrared microscope inspection apparatus (United States)

    Forman, Steven E.; Caunt, James W.


    Apparatus and system for inspecting infrared transparents, such as an array of photovoltaic modules containing silicon solar cells, includes an infrared microscope, at least three sources of infrared light placed around and having their axes intersect the center of the object field and means for sending the reflected light through the microscope. The apparatus is adapted to be mounted on an X-Y translator positioned adjacent the object surface.

  12. High speed infrared radiation thermometer, system, and method (United States)

    Markham, James R.


    The high-speed radiation thermometer has an infrared measurement wavelength band that is matched to the infrared wavelength band of near-blackbody emittance of ceramic components and ceramic thermal barrier coatings used in turbine engines. It is comprised of a long wavelength infrared detector, a signal amplifier, an analog-to-digital converter, an optical system to collect radiation from the target, an optical filter, and an integral reference signal to maintain a calibrated response. A megahertz range electronic data acquisition system is connected to the radiation detector to operate on raw data obtained. Because the thermometer operates optimally at 8 to 12 .mu.m, where emittance is near-blackbody for ceramics, interferences to measurements performed in turbine engines are minimized. The method and apparatus are optimized to enable mapping of surface temperatures on fast moving ceramic elements, and the thermometer can provide microsecond response, with inherent self-diagnostic and calibration-correction features.

  13. Ensuring long-term stability of infrared camera absolute calibration. (United States)

    Kattnig, Alain; Thetas, Sophie; Primot, Jérôme


    Absolute calibration of cryogenic 3-5 µm and 8-10 µm infrared cameras is notoriously instable and thus has to be repeated before actual measurements. Moreover, the signal to noise ratio of the imagery is lowered, decreasing its quality. These performances degradations strongly lessen the suitability of Infrared Imaging. These defaults are often blamed on detectors reaching a different "response state" after each return to cryogenic conditions, while accounting for the detrimental effects of imperfect stray light management. We show here that detectors are not to be blamed and that the culprit can also dwell in proximity electronics. We identify an unexpected source of instability in the initial voltage of the integrating capacity of detectors. Then we show that this parameter can be easily measured and taken into account. This way we demonstrate that a one month old calibration of a 3-5 µm camera has retained its validity.

  14. Using a CO2 laser for PIR-detector spoofing

    NARCIS (Netherlands)

    Schleijpen, R.; Putten, F.J.M. van


    This paper presents experimental work on the use of a CO2 laser for triggering of PIR sensors. Pyro-electric InfraRed sensors are often used as motion detectors for detection of moving persons or objects that are warmer than their environment. Apart from uses in the civilian domain, also

  15. Far infrared supplement: Catalog of infrared observations, second edition

    International Nuclear Information System (INIS)

    Gezari, D.Y.; Schmitz, M.; Mead, J.M.


    The Far Infrared Supplement: Catalog of Infrared Observations summarizes all infrared astronomical observations at far infrared wavelengths (5 to 1000 microns) published in the scientific literature from 1965 through 1986. The Supplement list contain 25 percent of the observations in the full Catalog of Infrared Observations (CIO), and essentially eliminates most visible stars from the listings. The Supplement is thus more compact than the main catalog, and is intended for easy reference during astronomical observations. The Far Infrared Supplement (2nd Edition) includes the Index of Infrared Source Positions and the Bibliography of Infrared Astronomy for the subset of far infrared observations listed

  16. Mid-Infrared Lasers (United States)

    National Aeronautics and Space Administration — Mid infrared solid state lasers for Differential Absorption Lidar (DIAL) systems required for understanding atmospheric chemistry are not available. This program...

  17. Influence of material and geometry on the performance of superconducting nanowire single-photon detectors

    CERN Document Server

    Henrich, Dagmar


    Superconducting Nanowire Single-Photon Detectors offer the capability to detect electromagnetic waves on a single photon level in a wavelength range that far exceeds that of alternative detector types. However, above a certain threshold wavelength, the efficiency of those detectors decreases stronlgy, leading to a poor performance in the far-infrared range. Influences on this threshold are studied and approaches for improvement are verified experimentally by measurement of the device performance.

  18. Laser and beta source setup characterization of 3D-DDTC detectors fabricated at FBK-irst

    Energy Technology Data Exchange (ETDEWEB)

    Zoboli, A. [INFN, Sezione di Padova (Gruppo Collegato di Trento), and Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, Via Sommarive, 14, I-38050 Povo (Trento) (Italy)], E-mail:; Dalla Betta, G.-F. [INFN, Sezione di Padova (Gruppo Collegato di Trento), and Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, Via Sommarive, 14, I-38050 Povo (Trento) (Italy); Boscardin, M. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi, Via Sommarive, 18, I-38050 Povo (Trento) (Italy); Bosisio, L. [Dip. di Fisica e INFN, Universita di Trieste, I-34127, Trieste (Italy); Eckert, S.; Kuehn, S.; Parzefall, U. [Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany); Piemonte, C.; Ronchin, S.; Zorzi, N. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi, Via Sommarive, 18, I-38050 Povo (Trento) (Italy)


    We report on the functional characterization of the first batch of 3D Double-Sided Double Type Column (3D-DDTC) detectors fabricated at FBK, Trento. This detector concept represents the evolution of the previous 3D-STC detectors towards full 3D detectors, and is expected to achieve a performance which is comparable to standard 3D detectors, but with a simpler fabrication process. Measurements were performed on detectors in the microstrip configuration coupled to the ATLAS ABCD3T binary readout. This paper reports spatially resolved signal efficiency tests made with a pulsed infrared laser setup and charge collection efficiency tests made with a Beta source.

  19. Laser and beta source setup characterization of 3D-DDTC detectors fabricated at FBK-irst

    International Nuclear Information System (INIS)

    Zoboli, A.; Dalla Betta, G.-F.; Boscardin, M.; Bosisio, L.; Eckert, S.; Kuehn, S.; Parzefall, U.; Piemonte, C.; Ronchin, S.; Zorzi, N.


    We report on the functional characterization of the first batch of 3D Double-Sided Double Type Column (3D-DDTC) detectors fabricated at FBK, Trento. This detector concept represents the evolution of the previous 3D-STC detectors towards full 3D detectors, and is expected to achieve a performance which is comparable to standard 3D detectors, but with a simpler fabrication process. Measurements were performed on detectors in the microstrip configuration coupled to the ATLAS ABCD3T binary readout. This paper reports spatially resolved signal efficiency tests made with a pulsed infrared laser setup and charge collection efficiency tests made with a Beta source.

  20. Nuclear radiation detectors

    International Nuclear Information System (INIS)

    Kapoor, S.S.; Ramamurthy, V.S.


    The present monograph is intended to treat the commonly used detectors in the field of nuclear physics covering important developments of the recent years. After a general introduction, a brief account of interaction of radiation with matter relevant to the processes in radiation detection is given in Chapter II. In addition to the ionization chamber, proportional counters and Geiger Mueller counters, several gas-filled detectors of advanced design such as those recently developed for heavy ion physics and other types of studies have been covered in Chapter III. Semiconductor detectors are dealt with in Chapter IV. The scintillation detectors which function by sensing the photons emitted by the luminescence process during the interaction of the impinging radiation with the scintillation detector medium are described in Chapter V. The topic of neutron detectors is covered in Chapter VI, as in this case the emphasis is more on the method of neutron detection rather than on detector type. Electronic instrumentation related to signal pulse processing dealt with in Chapter VII. The track etch detectors based on the visualization of the track of the impinging charge particle have also been briefly covered in the last chapter. The scope of this monograph is confined to detectors commonly used in low and medium energy nuclear physics research and applications of nuclear techniques. The monograph is intended for post-graduate students and those beginning to work with the radiation detectors. (author)

  1. Detectors for Particle Radiation (United States)

    Kleinknecht, Konrad


    This textbook provides a clear, concise and comprehensive review of the physical principles behind the devices used to detect charged particles and gamma rays, and the construction and performance of these many different types of detectors. Detectors for high-energy particles and radiation are used in many areas of science, especially particle physics and nuclear physics experiments, nuclear medicine, cosmic ray measurements, space sciences and geological exploration. This second edition includes all the latest developments in detector technology, including several new chapters covering micro-strip gas chambers, silicion strip detectors and CCDs, scintillating fibers, shower detectors using noble liquid gases, and compensating calorimeters for hadronic showers. This well-illustrated textbook contains examples from the many areas in science in which these detectors are used. It provides both a coursebook for students in physics, and a useful introduction for researchers in other fields.

  2. Silicon Telescope Detectors

    CERN Document Server

    Gurov, Yu B; Sandukovsky, V G; Yurkovski, J


    The results of research and development of special silicon detectors with a large active area ($> 8 cm^{2}$) for multilayer telescope spectrometers (fulfilled in the Laboratory of Nuclear Problems, JINR) are reviewed. The detector parameters are listed. The production of totally depleted surface barrier detectors (identifiers) operating under bias voltage two to three times higher than depletion voltage is described. The possibility of fabrication of lithium drifted counters with a very thin entrance window on the diffusion side of the detector (about 10--20 $\\mu$m) is shown. The detector fabrication technique has allowed minimizing detector dead regions without degradation of their spectroscopic characteristics and reliability during long time operation in charge particle beams.

  3. Physics of scintillation detectors

    International Nuclear Information System (INIS)

    Novotny, R.


    The general concept of a radiation detector is based on three fundamental principles: sensitivity of the device to the radiation of interest which requires a large cross-section in the detector material, detector response function to the physical properties of the radiation. As an example, a scintillation detector for charged particles should allow to identify the charge of the particle, its kinetic energy and the time of impact combined with optimum resolutions. Optimum conversion of the detector response (like luminescence of a scintillator) into electronical signals for further processing. The following article will concentrate on the various aspects of the first two listed principles as far as they appear to be relevant for photon and charged particle detection using organic and inorganic scintillation detectors. (orig.)

  4. On infrared divergences

    International Nuclear Information System (INIS)

    Parisi, G.


    The structure of infrared divergences is studied in superrenormalizable interactions. It is conjectured that there is an extension of the Bogoliubov-Parasiuk-Hepp theorem which copes also with infrared divergences. The consequences of this conjecture on the singularities of the Borel transform in a massless asymptotic free field theory are discussed. The application of these ideas to gauge theories is briefly discussed. (Auth.)

  5. Apparatus and method for transient thermal infrared spectrometry (United States)

    McClelland, John F.; Jones, Roger W.


    A method and apparatus for enabling analysis of a material (16, 42) by applying a cooling medium (20, 54) to cool a thin surface layer portion of the material and to transiently generate a temperature differential between the thin surface layer portion and the lower portion of the material sufficient to alter the thermal infrared emission spectrum of the material from the black-body thermal infrared emission spectrum of the material. The altered thermal infrared emission spectrum of the material is detected by a spectrometer/detector (28, 50) while the altered thermal infrared emission spectrum is sufficiently free of self-absorption by the material of the emitted infrared radiation. The detection is effected prior to the temperature differential propagating into the lower portion of the material to an extent such that the altered thermal infrared emission spectrum is no longer sufficiently free of self-absorption by the material of emitted infrared radiation, so that the detected altered thermal infrared emission spectrum is indicative of the characteristics relating to the molecular composition of the material.

  6. The Infrared Astronomical Satellite (IRAS) mission (United States)

    Neugebauer, G.; Habing, H. J.; Van Duinen, R.; Aumann, H. H.; Beichman, C. A.; Baud, B.; Beintema, D. A.; Boggess, N.; Clegg, P. E.; De Jong, T.


    The Infrared Astronomical Satellite (IRAS) consists of a spacecraft and a liquid helium cryostat that contains a cooled IR telescope. The telescope's focal plane assembly is cooled to less than 3 K, and contains 62 IR detectors in the survey array which are arranged so that every source crossing the field of view can be seen by at least two detectors in each of four wavelength bands. The satellite was launched into a 900 km-altitude near-polar orbit, and its cryogenic helium supply was exhausted on November 22, 1983. By mission's end, 72 percent of the sky had been observed with three or more hours-confirming scans, and 95 percent with two or more hours-confirming scans. About 2000 stars detected at 12 and 25 microns early in the mission, and identified in the SAO (1966) catalog, have a positional uncertainty ellipse whose axes are 45 x 9 arcsec for an hours-confirmed source.

  7. The atlas detector

    International Nuclear Information System (INIS)

    Perrodo, P.


    The ATLAS detector, one of the two multi-purpose detectors at the Large Hadron Collider at CERN, is currently being built in order to meet the first proton-proton collisions in time. A description of the detector components will be given, corresponding to the most up to date design and status of construction, completed with test beam results and performances of the first serial modules. (author)

  8. Cherenkov water detector NEVOD (United States)

    Petrukhin, A. A.


    A unique multipurpose Cherenkov water detector, the NEVOD facility, uses quasispherical measuring modules to explore all the basic components of cosmic rays on Earth's surface, including neutrinos. Currently, the experimental complex includes the Cherenkov water detector, a calibration telescope system, and a coordinate detector. This paper traces the basic development stages of NEVOD, examines research directions, presents the results obtained, including the search for the solution to the 'muon puzzle', and discusses possible future development prospects.

  9. Noble Gas Detectors

    CERN Document Server

    Aprile, Elena; Bolozdynya, Alexander I; Doke, Tadayoshi


    This book discusses the physical properties of noble fluids, operational principles of detectors based on these media, and the best technical solutions to the design of these detectors. Essential attention is given to detector technology: purification methods and monitoring of purity, information readout methods, electronics, detection of hard ultra-violet light emission, selection of materials, cryogenics etc.The book is mostly addressed to physicists and graduate students involved in the preparation of fundamental next generation experiments, nuclear engineers developing instrumentation

  10. Study on Silicon detectors

    International Nuclear Information System (INIS)

    Gervino, G.; Boero, M.; Manfredotti, C.; Icardi, M.; Gabutti, A.; Bagnolatti, E.; Monticone, E.


    Prototypes of Silicon microstrip detectors and Silicon large area detectors (3x2 cm 2 ), realized directly by our group, either by ion implantation or by diffusion are presented. The physical detector characteristics and their performances determined by exposing them to different radioactive sources and the results of extensive tests on passivation, where new technological ways have been investigated, are discussed. The calculation of the different terms contributing to the total dark current is reported

  11. The solenoidal detector collaboration silicon detector system

    International Nuclear Information System (INIS)

    Ziock, H.J.; Gamble, M.T.; Miller, W.O.; Palounek, A.P.T.; Thompson, T.C.


    Silicon tracking systems (STS) will be fundamental components of the tracking systems for both planned major SSC experiments. The STS is physically a small part of the central tracking system and the calorimeter of the detector being proposed by the Solenoidal Detector Collaboration (SDC). Despite its seemingly small size, it occupies a volume of more than 5 meters in length and 1 meter in diameter and is an order of magnitude larger than any silicon detector system previously built. The STS will consist of silicon microstrip detectors and possibly silicon pixel detectors. The other two components are an outer barrel tracker, which will consist of straw tubes or scintillating fibers; and an outer intermediate angle tracker, which will consist of gas microstrips. The components are designed to work as an integrated system. Each componenet has specific strengths, but is individually incapable of providing the overall performance required by the physics goals of the SSC. The large particle fluxes, the short times between beam crossing, the high channel count, and the required very high position measurement accuracy pose challenging problems that must be solved. Furthermore, to avoid degrading the measurements, the solutions must be achieved using only a minimal amount of material. An additional constraint is that only low-Z materials are allowed. If that were not difficlut enough, the solutions must also be affordable

  12. Bursting Smoke as an Infrared Countermeasure


    Amarjit Singh; P. J. Kamale; S. A. Joshi; L. K. Bankar


    This paper describes the experimental setup for the evaluation of bursting smoke for anti-infrared role using SR-5000 spectroradiometer and a source of IR radiation (8-13 micrometer) using cadmium-mercury-telluride (CMI) detector cooled by liquid nitrogen. The particle size and shape of the powders used in the bursting smokes were determined microscopically using Carl Zeiss Jena Neophot- 21. Highest attenuation of 97 -lOO percent was produced for about 12 s using a mixture of bronze fl...

  13. Infrared solar physics from the South Pole (United States)

    Deming, Drake


    Infrared (IR) observations of the sun could greatly benefit from the quality of the South Pole as an IR site, and the potential for multi-day sequences of uninterrupted observations. A nearly continuous picture of the evolution of the magnetic field in solar active regions could be obtained using vector magnetographs, especially vector magnetographs which incorporate IR array detectors. Observations of the sun over a range of wavelengths in the IR continuum could also be used to study the vertical propagation characteristics of the solar p-mode oscillations.

  14. Near-infrared scintillation of liquid argon

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, T. [Fermilab; Escobar, C. O. [Campinas State U.; Lippincott, W. H. [Fermilab; Rubinov, P. [Fermilab


    Since the 1970s it has been known that noble gases scintillate in the near infrared (NIR) region of the spectrum (0.7 $\\mu$m < $\\lambda$; < 1.5$\\mu$m). More controversial has been the question of the NIR light yield for condensed noble gases. We first present the motivation for using the NIR scintillation in liquid argon detectors, then briefly review early as well as more recent efforts and finally show encouraging preliminary results of a test performed at Fermilab.

  15. Multi-channel near infrared spectroradiometer

    International Nuclear Information System (INIS)

    Joseph, G.B.; Biddles, B.J.; D'silva, R.A.; Picot, A.J.; Ackerman, M.J.


    A multichannel spectroradiometer has been developed by Sira Ltd. for the study of rapidly varying events in the near infrared. The instrument is being used in the examination of gun flashes, rocket motor exhaust efflux analysis and ordnance or pyrotechnic flash studies. The spectral range of about 1.4 to 5.2 microns is covered in two bands with the first order dispersion from a pair of ruled blazed gratings being imaged onto a pair of detector arrays. Data may be logged at a rate of 1000 complete spectra per second

  16. Infrared laser scattering system for plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Muraoka, K; Hiraki, N; Kawasaki, S [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics


    The possibility of observing the collective scattering of infrared laser light from plasmas is discussed in terms of the laser power requirement, the necessary optical system and the detector performance, and is shown to be feasible with the present day techniques to get the ion temperature by means of a CO/sub 2/ laser on theta pinch plasmas. Based on this estimate, the construction of the TEA CO/sub 2/ laser and the preparations of the optical components have been started and some preliminary results of these are described.

  17. Infrared laser scattering system for plasma diagnostics

    International Nuclear Information System (INIS)

    Muraoka, Katsunori; Hiraki, Naoji; Kawasaki, Shoji


    The possibility of observing the collective scattering of infrared laser light from plasmas is discussed in terms of the laser power requirement, the necessary optical system and the detector performance, and is shown to be feasible with the present day techniques to get the ion temperature by means of a CO 2 laser on theta pinch plasmas. Based on this estimate, the construction of the TEA CO 2 laser and the preparations of the optical components have been started and some preliminary results of these are described. (auth.)

  18. LHCb Detector Performance

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Geraci, Angelo; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, V.V.; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Pessina, Gianluigi; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilschut, Hans; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander


    The LHCb detector is a forward spectrometer at the Large Hadron Collider (LHC) at CERN. The experiment is designed for precision measurements of CP violation and rare decays of beauty and charm hadrons. In this paper the performance of the various LHCb sub-detectors and the trigger system are described, using data taken from 2010 to 2012. It is shown that the design criteria of the experiment have been met. The excellent performance of the detector has allowed the LHCb collaboration to publish a wide range of physics results, demonstrating LHCb's unique role, both as a heavy flavour experiment and as a general purpose detector in the forward region.

  19. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration


    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS (A Toroidal LHC Apparatus). The ALFA system is composed by four stations installed in the LHC tunnel 240 m away from the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronics for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  20. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration


    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS/LHC. The ALFA system is composed by two stations installed in the LHC tunnel 240 m away from each side of the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronic for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  1. The LHC detector challenge

    CERN Document Server

    Virdee, Tejinder S


    The Large Hadron Collider (LHC) from CERN, scheduled to come online in 2007, is a multi-TeV proton-proton collider with vast detectors. Two of the more significant detectors for LHC are ATLAS and CMS. Currently, both detectors are more than 65% complete in terms of financial commitment, and the experiments are being assembled at an increasing pace. ATLAS is being built directly in its underground cavern, whereas CMS is being assembled above ground. When completed, both detectors will aid researchers in determining what lies at the high-energy frontier, in particular the mechanism by which particles attain mass. (Edited abstract).

  2. Apparatus and method for transient thermal infrared emission spectrometry (United States)

    McClelland, John F.; Jones, Roger W.


    A method and apparatus for enabling analysis of a solid material (16, 42) by applying energy from an energy source (20, 70) top a surface region of the solid material sufficient to cause transient heating in a thin surface layer portion of the solid material (16, 42) so as to enable transient thermal emission of infrared radiation from the thin surface layer portion, and by detecting with a spectrometer/detector (28, 58) substantially only the transient thermal emission of infrared radiation from the thin surface layer portion of the solid material. The detected transient thermal emission of infrared radiation is sufficiently free of self-absorption by the solid material of emitted infrared radiation, so as to be indicative of characteristics relating to molecular composition of the solid material.

  3. Preparation of bubble damage detectors

    International Nuclear Information System (INIS)

    Tu Caiqing; Guo Shilun; Wang Yulan; Hao Xiuhong; Chen Changmao; Su Jingling


    Bubble damage detectors have been prepared by using polyacrylamide as detector solid and freon as detector liquid. Tests show that the prepared detectors are sensitive to fast neutrons and have proportionality between bubble number and neutron fluence within a certain range of neutron fluence. Therefore, it can be used as a fast neutron detector and a dosimeter

  4. Test of the TRAPPISTe monolithic detector system (United States)

    Soung Yee, L.; Álvarez, P.; Martin, E.; Cortina, E.; Ferrer, C.


    A monolithic pixel detector named TRAPPISTe-2 has been developed in Silicon-on-Insulator (SOI) technology. A p-n junction is implanted in the bottom handle wafer and connected to readout electronics integrated in the top active layer. The two parts are insulated from each other by a buried oxide layer resulting in a monolithic detector. Two small pixel matrices have been fabricated: one containing a 3-transistor readout and a second containing a charge sensitive amplifier readout. These two readout structures have been characterized and the pixel matrices were tested with an infrared laser source. The readout circuits are adversely affected by the backgate effect, which limits the voltage that can be applied to the metal back plane to deplete the sensor, thus narrowing the depletion width of the sensor. Despite the low depletion voltages, the integrated pixel matrices were able to respond to and track a laser source.

  5. Methods of manufacturing a detector device

    International Nuclear Information System (INIS)

    Wotherspoon, J.T.M.


    In the manufacture of an infra-red radiation detector device, a body of rho-type cadmium mercury telluride is bombarded with ions to etch away a part of the body and to produce from the etched-away part of the body an excess concentration of mercury which acts as a dopant source converting an adjacent part of the body into n-type material. The energy of the bombarding ions is less than 30 keV, and by appropriately choosing the ion dose this conversion can be effected over a depth considerably greater than the penetration depth of the ions. A p-n junction can be fabricated in this way for a photovoltaic detector. The conductivity type conversion may even be effected through the body thickness. The etching and conversion can be localised by masking part of the body surface against the ion bombardment. (author)

  6. High resolution imaging detectors and applications

    CERN Document Server

    Saha, Swapan K


    Interferometric observations need snapshots of very high time resolution of the order of (i) frame integration of about 100 Hz or (ii) photon-recording rates of several megahertz (MHz). Detectors play a key role in astronomical observations, and since the explanation of the photoelectric effect by Albert Einstein, the technology has evolved rather fast. The present-day technology has made it possible to develop large-format complementary metal oxide–semiconductor (CMOS) and charge-coupled device (CCD) array mosaics, orthogonal transfer CCDs, electron-multiplication CCDs, electron-avalanche photodiode arrays, and quantum-well infrared (IR) photon detectors. The requirements to develop artifact-free photon shot noise-limited images are higher sensitivity and quantum efficiency, reduced noise that includes dark current, read-out and amplifier noise, smaller point-spread functions, and higher spectral bandwidth. This book aims to address such systems, technologies and design, evaluation and calibration, control...

  7. ALICE Photon Multiplicity Detector

    CERN Multimedia

    Nayak, T


    Photon Multiplicity Detector (PMD) measures the multiplicity and spatial distribution of photons in the forward region of ALICE on a event-by-event basis. PMD is a pre-shower detector having fine granularity and full azimuthal coverage in the pseudo-rapidity region 2.3 < η < 3.9.

  8. New detector concepts

    International Nuclear Information System (INIS)

    Kemmer, J.; Lutz, G.


    On the basis of the semiconductor drift chamber many new detectors are proposed, which enable the determination of energy, energy loss, position and penetration depth of radiation. A novel integrated transistor-detector configuration allows non destructive repeated readout and amplification of the signal. The concept may be used for the construction of one or two-dimensional PIXEL arrays. (orig.)

  9. Stanford's big new detector

    International Nuclear Information System (INIS)



    A detector constructed for the Standford Linear Collider is described. It consists of a central drift chamber in the field of a surrounding superconducting solenoid. Furthermore included are a Cherenkov ring imaging detector for particle identification and a liquid argon calorimeter. (HSI).

  10. CMS Detector Posters

    CERN Multimedia


    CMS Detector posters (produced in 2000): CMS installation CMS collaboration From the Big Bang to Stars LHC Magnetic Field Magnet System Trackering System Tracker Electronics Calorimetry Eletromagnetic Calorimeter Hadronic Calorimeter Muon System Muon Detectors Trigger and data aquisition (DAQ) ECAL posters (produced in 2010, FR & EN): CMS ECAL CMS ECAL-Supermodule cooling and mechatronics CMS ECAL-Supermodule assembly

  11. Pixel detector readout chip

    CERN Multimedia


    Close-up of a pixel detector readout chip. The photograph shows an aera of 1 mm x 2 mm containing 12 separate readout channels. The entire chip contains 1000 readout channels (around 80 000 transistors) covering a sensitive area of 8 mm x 5 mm. The chip has been mounted on a silicon detector to detect high energy particles.

  12. Drift chamber detectors

    International Nuclear Information System (INIS)

    Duran, I.; Martinez Laso, L.


    A review of High Energy Physics detectors based on drift chambers is presented. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysied, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author)

  13. Drift Chambers detectors

    International Nuclear Information System (INIS)

    Duran, I.; Martinez laso, L.


    We present here a review of High Energy Physics detectors based on drift chambers. The ionization, drift diffusion, multiplication and detection principles are described. Most common drift media are analysed, and a classification of the detectors according to its geometry is done. Finally the standard read-out methods are displayed and the limits of the spatial resolution are discussed. (Author) 115 refs

  14. Solid state track detectors

    International Nuclear Information System (INIS)

    Reuther, H.


    This paper gives a survey of the present state of the development and the application of solid state track detectors. The fundamentals of the physical and chemical processes of the track formation and development are explained, the different detector materials and their registration characteristics are mentioned, the possibilities of the experimental practice and the most variable applications are discussed. (author)

  15. LHCb detector performance

    NARCIS (Netherlands)

    Aaij, R.; Adeva, B.; Adinol, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Onderwater, C. J. G.; Pellegrino, A.; Wilschut, H. W.


    The LHCb detector is a forward spectrometer at the Large Hadron Collider (LHC) at CERN. The experiment is designed for precision measurements of CP violation and rare decays of beauty and charm hadrons. In this paper the performance of the various LHCb sub-detectors and the trigger system are

  16. The LDC detector concept

    Indian Academy of Sciences (India)

    Abstract. In preparation of the experimental program at the international linear collider (ILC), the large detector concept (LDC) is being developed. The main points of the LDC are a large volume gaseous tracking system, combined with high precision vertex detector and an extremely granular calorimeter. The main design ...

  17. Detector Systems at CLIC

    CERN Document Server

    Simon, Frank


    The Compact Linear Collider CLIC is designed to deliver e+e- collisions at a center of mass energy of up to 3 TeV. The detector systems at this collider have to provide highly efficient tracking and excellent jet energy resolution and hermeticity for multi-TeV final states with multiple jets and leptons. In addition, the detector systems have to be capable of distinguishing physics events from large beam-induced background at a crossing frequency of 2 GHz. Like for the detector concepts at the ILC, CLIC detectors are based on event reconstruction using particle flow algorithms. The two detector concepts for the ILC, ILD and SID, were adapted for CLIC using calorimeters with dense absorbers limiting leakage through increased compactness, as well as modified forward and vertex detector geometries and precise time stamping to cope with increased background levels. The overall detector concepts for CLIC are presented, with particular emphasis on the main detector and engineering challenges, such as: the ultra-thi...

  18. Future particle detector systems

    International Nuclear Information System (INIS)

    Clark, Allan G.


    Starting with a short summary of the major new experimental physics programs, we attempt to motivate the reasons why existing general-purpose detectors at Hadron Colliders are what they are, why they are being upgraded, and why new facilities are being constructed. The CDF and ATLAS detectors are used to illustrate these motivations. Selected physics results from the CDF experiment provide evidence for limitations on the detector performance, and new physics opportunities motivate both machine and detector upgrades. This is discussed with emphasis on the improved physics reach of the CDF experiment at the Fermilab Tevatron (√(s)=2 TeV). From 2005, the Large Hadron Collider (LHC) at CERN will become operational at a collision energy of √(s)=14 TeV, seven times larger than at the Tevatron Collider. To exploit the physics capability of the LHC, several large detectors are being constructed. The detectors are significantly more complex than those at the Tevatron Collider because of physics and operational constraints. The detector design and technology of the aspects of the large general-purpose detector ATLAS is described

  19. Developments on RICH detectors

    International Nuclear Information System (INIS)

    Besson, P.; Bourgeois, P.


    The RICH (ring imaging Cherenkov) detector which is dedicated to Cherenkov radiation detection is described. An improvement made by replacing photo sensible vapor with solid photocathode is studied. A RICH detector prototype with a CsI photocathode has been built in Saclay and used with Saturne. The first results are presented. (A.C.)

  20. ALICE Silicon Strip Detector

    CERN Multimedia

    Nooren, G


    The Silicon Strip Detector (SSD) constitutes the two outermost layers of the Inner Tracking System (ITS) of the ALICE Experiment. The SSD plays a crucial role in the tracking of the particles produced in the collisions connecting the tracks from the external detectors (Time Projection Chamber) to the ITS. The SSD also contributes to the particle identification through the measurement of their energy loss.

  1. Miniaturized multi channel infrared optical gas sensor system (United States)

    Wöllenstein, Jürgen; Eberhardt, Andre; Rademacher, Sven; Schmitt, Katrin


    Infrared spectroscopy uses the characteristic absorption of the molecules in the mid infrared and allows the determination of the gases and their concentration. Especially by the absorption at longer wavelengths between 8 μm and 12 μm, the so called "fingerprint" region, the molecules can be measured with highest selectivity. We present an infrared optical filter photometer for the analytical determination of trace gases in the air. The challenge in developing the filter photometer was the construction of a multi-channel system using a novel filter wheel concept - which acts as a chopper too- in order to measure simultaneously four gases: carbon monoxide, carbon dioxide, methane and ammonia. The system consists of a broadband infrared emitter, a long path cell with 1.7m optical path length, a filter wheel and analogue and digital signal processing. Multi channel filter photometers normally need one filter and one detector per target gas. There are small detection units with one, two or more detectors with integrated filters available on the market. One filter is normally used as reference at a wavelength without any cross-sensitivities to possible interfering gases (e.g. at 3.95 μm is an "atmospheric window" - a small spectral band without absorbing gases in the atmosphere). The advantage of a filter-wheel set-up is that a single IR-detector can be used, which reduces the signal drift enormously. Pyroelectric and thermopile detectors are often integrated in these kinds of spectrometers. For both detector types a modulation of the light is required and can be done - without an additional chopper - with the filter wheel.

  2. The GDH-Detector

    CERN Document Server

    Helbing, K; Fausten, M; Menze, D; Michel, T; Nagel, A; Ryckbosch, D; Speckner, T; Vyver, R V D; Zeitler, G


    For the GDH-Experiment at ELSA, the helicity dependent total photoabsorption cross-section is to be determined. These measurements will be performed with the newly developed GDH-Detector which is presented here. The concept of the GDH-Detector is to detect at least one reaction product from all possible hadronic processes with almost complete acceptance concerning solid angle and efficiency. This is realized by an arrangement of scintillators and lead. The overall acceptance for hadronic processes is better than 99%. The electromagnetic background is suppressed by about five orders of magnitude by means of a threshold Cherenkov detector. In dedicated tests, it has been demonstrated that all individual components of the GDH-Detector fulfill the design goals. Measurements of unpolarized total photoabsorption cross-sections were performed to ensure that the complete GDH-Detector is operational.

  3. Introduction to detectors

    CERN Document Server

    Walenta, Albert H


    Concepts for momentum measurements,particle identification and energy measurements (calorimeters) as well for imaging applications in medecine, biology and industry (non destructive testing) will be put into relation to the specific detection princip In particular the resolution for position, time, energy and intensity measurement and the efficiency will be discussed. Signal extraction,electronic signal processing and principles of information capture will close the logic circle to the input : the radiation properties.The lecture will provide some sources for data tables and small demonstration computer programs f The basic detector physics as interaction of radiation with matter, information transport via free charges,photons and phonons and the signal formation will be presented in some depth with emphasis on the influence on specific parameters for detector The lecture will cover the most popular detector principles, gas detectors (ion chambers,MPWC's and MSGC's), semiconductor detectors scintillators and ...

  4. ATLAS ITk Pixel detector

    CERN Document Server

    Gemme, Claudia; The ATLAS collaboration


    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenge to the ATLAS tracker. The current inner detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation level are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLA Pixel detector developments as well as the various layout options will be reviewed.

  5. Undepleted silicon detectors

    International Nuclear Information System (INIS)

    Rancoita, P.G.; Seidman, A.


    Large-size silicon detectors employing relatively low resistivity material can be used in electromagnetic calorimetry. They can operate in strong magnetic fields, under geometric constraints and with microstrip detectors a high resolution can be achieved. Low noise large capacitance oriented electronics was developed to enable good signal-to-noise ratio for single relativistic particles traversing large area detectors. In undepleted silicon detectors, the charge migration from the field-free region has been investigated by comparing the expected peak position (from the depleted layer only) of the energy-loss of relativistic electrons with the measured one. Furthermore, the undepleted detectors have been employed in a prototype of Si/W electromagnetic colorimeter. The sensitive layer was found to be systematically larger than the depleted one

  6. Charged corpuscular beam detector

    Energy Technology Data Exchange (ETDEWEB)

    Hikawa, H; Nishikawa, Y


    The present invention relates to a charged particle beam detector which prevents transient phenomena disturbing the path and focusing of a charged particle beam travelling through a mounted axle. The present invention provides a charged particle beam detector capable of decreasing its reaction to the charge in energy of the charged particle beam even if the relative angle between the mounted axle and the scanner is unstable. The detector is characterized by mounting electrically conductive metal pieces of high melting point onto the face of a stepped, heat-resistant electric insulating material such that the pieces partially overlap each other and individually provide electric signals, whereby the detector is no longer affected by the beam. The thickness of the metal piece is selected so that an eddy current is not induced therein by an incident beam, thus the incident beam is not affected. The detector is capable of detecting a misaligned beam since the metal pieces partially overlap each other.

  7. Real-time imaging systems for superconducting nanowire single-photon detector arrays

    Energy Technology Data Exchange (ETDEWEB)

    Hofherr, Matthias


    Superconducting nanowire singe-photon detectors (SNSPD) are promising detectors in the field of applications, where single-photon resolution is required like in quantum optics, spectroscopy or astronomy. These cryogenic detectors gain from a broad spectrum in the optical and infrared range and deliver low dark counts and low jitter. This work provides a piece of deeper physical understanding of detector functionality in combination with highly engineered readout development. A detailed analysis focuses on the intrinsic detection mechanism of SNSPDs related to the detection in the infrared regime and the evolution of dark counts. With this fundamental knowledge, the next step is the development of a multi-pixel readout at cryogenic conditions. It is demonstrated, how two auspicious multi-pixel readout concepts can be realized, which enables statistical framing like in imaging applications using RSFQ electronics with fast framing rates and the readout of a detector array with continuous real-time single-photon resolution.

  8. Life-finding detector development at NASA GSFC using a custom H4RG test bed (United States)

    Mosby, Gregory; Rauscher, Bernard; Kutyrev, Alexander


    Chemical species associated with life, called biosignatures, should be visible in exoplanet atmospheres with larger space telescopes. These signals will be faint and require very low noise (~e-) detectors to robustly measure. At NASA Goddard we are developing a single detector H4RG test bed to characterize and identify potential technology developments needed for the next generation's large space telescopes. The vacuum and cryogenic test bed will include near infrared light sources from integrating spheres using a motorized shutter. The detector control and readout will be handled by a Leach controller. Detector cables have been manufactured and test planning has begun. Planned tests include testing minimum read noise capabilities, persistence mitigation strategies using long wavelength light, and measuring intrapixel variation which might affect science goals of future missions. In addition to providing a means to identify areas of improvement in detector technology, we hope to use this test bed to probe some fundamental physics of these infrared arrays.

  9. The Solenoidal Detector Collaboration silicon detector system

    International Nuclear Information System (INIS)

    Ziock, H.J.; Gamble, M.T.; Miller, W.O.; Palounek, A.P.T.; Thompson, T.C.


    Silicon tracking systems will be fundamental components of the tracking systems for both planned major SSC experiments. Despite its seemingly small size, it occupies a volume of more than 5 meters in length and 1 meter in diameter and is an order of magnitude larger than any silicon detector system previously built. This report discusses its design and operation

  10. CDF [Collider Detector at Fermilab] detector simulation

    International Nuclear Information System (INIS)

    Freeman, J.


    The Collider Detector at Fermilab (CDF) uses several different simulation programs, each tuned for specific applications. The programs rely heavily on the extensive test beam data that CDF has accumulated. Sophisticated shower parameterizations are used, yielding enormous gains in speed over full cascade programs. 3 refs., 5 figs

  11. Calibration Improvements in the Detector-to-Detector Differences for the MODIS Ocean Color Bands (United States)

    Li, Yonghong; Angal, Amit; Wu, Aisheng; Geng, Xu; Link, Daniel; Xiong, Xiaoxiong


    The Moderate Resolution Imaging Spectroradiometer (MODIS), a major instrument within NASAs Earth Observation System missions, has operated for over 16 and 14 years onboard the Terra and Aqua satellites, respectively. Its reflective solar bands (RSB) covering a spectral range from 0.4 to 2.1 micrometers are primarily calibrated using the on-board solar diffuser(SD), with its on-orbit degradation monitored using the Solar Diffuser Stability Monitor. RSB calibrations are supplemented by near-monthly lunar measurements acquired from the instruments space-view port. Nine bands (bands 8-16) in the visible to near infrared spectral range from 0.412 to 0.866 micrometers are primarily used for ocean color observations.During a recent reprocessing of ocean color products, performed by the NASA Ocean Biology Processing Group, detector-to-detector differences of up to 1.5% were observed in bands 13-16 of Terra MODIS. This paper provides an overview of the current approach to characterize the MODIS detector-to-detector differences. An alternative methodology was developed to mitigate the observed impacts for bands 13-16. The results indicated an improvement in the detector residuals and in turn are expected to improve the MODIS ocean color products. This paper also discusses the limitations,subsequent enhancements, and the improvements planned for future MODIS calibration collections.

  12. Scientific detectors for astronomy 2005 Explorers of the Photon Odyssey

    CERN Document Server

    Beletic, Jenna E; Amico, Paola


    Every three years, the leading experts in detectors for astronomy gather together to exchange information and form professional relationships. This series of meetings is entitled Scientific Detectors for Astronomy. The meeting has been held six times, with the last four publishing hardcover proceedings. Nearly all leading astronomical observatories and manufacturers attend this meeting, with participants from every continent of the world. The 2005 meeting in Taormina, Italy was attended by 127 professionals who develop and use the highest quality detectors for wavelengths from x-ray to sub-mm, with emphasis on optical and infrared detectors. The meeting consisted of overview talks, technical presentations, poster sessions and roundtable discussions. In addition, a strong cultural programme exposed the participants to the host region while fostering the enhancement of professional relationships. These proceedings capture the technical content and the spirit of the 2005 workshop. The 87 papers cover a wide rang...

  13. Ultra Low Noise Infrared Detector Amplifier for Next Generation Standoff Detector (United States)


    some mismatches. The formation of a heterojunction for the channel entails creating a sufficient degree of difference between the bandgap of the...metal oxide (MOS) capacitor, thereby isolating the ground from dc. EPIR Technologies, Inc. Proprietary Information – Exempt From FOIA 67 Figure

  14. Infrared emission from protostars

    International Nuclear Information System (INIS)

    Adams, F.C.; Shu, F.H.


    The emergent spectral energy distribution at infrared to radio wavelengths is calculated for the simplest theoretical construct of a low-mass protostar. It is shown that the emergent spectrum in the infrared is insensitive to the details assumed for the temperature profile as long as allowance is made for a transition from optically thick to optically thin conditions and luminosity conservation isenforced at the inner and outer shells. The radiation in the far infrared and submillimeter wavelengths depends on the exact assumptions made for grain opacities at low frequencies. An atlas of emergent spectral energy distributions is presented for a grid of values of the instantaneous mass of the protostar and the mass infall rate. The attenuated contribution of the accretion shock to the near-infrared radiation is considered. 50 references

  15. Additive Manufacturing Infrared Inspection (United States)

    Gaddy, Darrell; Nettles, Mindy


    The Additive Manufacturing Infrared Inspection Task started the development of a real-time dimensional inspection technique and digital quality record for the additive manufacturing process using infrared camera imaging and processing techniques. This project will benefit additive manufacturing by providing real-time inspection of internal geometry that is not currently possible and reduce the time and cost of additive manufactured parts with automated real-time dimensional inspections which deletes post-production inspections.

  16. Development and Production of Array Barrier Detectors at SCD (United States)

    Klipstein, P. C.; Avnon, E.; Benny, Y.; Berkowicz, E.; Cohen, Y.; Dobromislin, R.; Fraenkel, R.; Gershon, G.; Glozman, A.; Hojman, E.; Ilan, E.; Karni, Y.; Klin, O.; Kodriano, Y.; Krasovitsky, L.; Langof, L.; Lukomsky, I.; Nevo, I.; Nitzani, M.; Pivnik, I.; Rappaport, N.; Rosenberg, O.; Shtrichman, I.; Shkedy, L.; Snapi, N.; Talmor, R.; Tessler, R.; Weiss, E.; Tuito, A.


    XB n or XB p barrier detectors exhibit diffusion-limited dark currents comparable with mercury cadmium telluride Rule-07 and high quantum efficiencies. In 2011, SemiConductor Devices (SCD) introduced "HOT Pelican D", a 640 × 512/15- μm pitch InAsSb/AlSbAs XB n mid-wave infrared (MWIR) detector with a 4.2- μm cut-off and an operating temperature of ˜150 K. Its low power (˜3 W), high pixel operability (>99.5%) and long mean time to failure make HOT Pelican D a highly reliable integrated detector-cooler product with a low size, weight and power. More recently, "HOT Hercules" was launched with a 1280 × 1024/15- μm format and similar advantages. A 3-megapixel, 10- μm pitch version ("HOT Blackbird") is currently completing development. For long-wave infrared applications, SCD's 640 × 512/15- μm pitch "Pelican-D LW" XB p type II superlattice (T2SL) detector has a ˜9.3- μm cut-off wavelength. The detector contains InAs/GaSb and InAs/AlSb T2SLs, and is fabricated into focal plane array (FPA) detectors using standard production processes including hybridization to a digital silicon read-out integrated circuit (ROIC), glue underfill and substrate thinning. The ROIC has been designed so that the complete detector closely follows the interfaces of SCD's MWIR Pelican-D detector family. The Pelican-D LW FPA has a quantum efficiency of ˜50%, and operates at 77 K with a pixel operability of >99% and noise equivalent temperature difference of 13 mK at 30 Hz and F/2.7.

  17. ATLAS Detector Interface Group

    CERN Multimedia

    Mapelli, L

    Originally organised as a sub-system in the DAQ/EF-1 Prototype Project, the Detector Interface Group (DIG) was an information exchange channel between the Detector systems and the Data Acquisition to provide critical detector information for prototype design and detector integration. After the reorganisation of the Trigger/DAQ Project and of Technical Coordination, the necessity to provide an adequate context for integration of detectors with the Trigger and DAQ lead to organisation of the DIG as one of the activities of Technical Coordination. Such an organisation emphasises the ATLAS wide coordination of the Trigger and DAQ exploitation aspects, which go beyond the domain of the Trigger/DAQ project itself. As part of Technical Coordination, the DIG provides the natural environment for the common work of Trigger/DAQ and detector experts. A DIG forum for a wide discussion of all the detector and Trigger/DAQ integration issues. A more restricted DIG group for the practical organisation and implementation o...

  18. The HERMES recoil detector

    International Nuclear Information System (INIS)

    Airapetian, A.; Belostotski, S.


    For the final running period of HERA, a recoil detector was installed at the HERMES experiment to improve measurements of hard exclusive processes in charged-lepton nucleon scattering. Here, deeply virtual Compton scattering is of particular interest as this process provides constraints on generalised parton distributions that give access to the total angular momenta of quarks within the nucleon. The HERMES recoil detector was designed to improve the selection of exclusive events by a direct measurement of the four-momentum of the recoiling particle. It consisted of three components: two layers of double-sided silicon strip sensors inside the HERA beam vacuum, a two-barrel scintillating fibre tracker, and a photon detector. All sub-detectors were located inside a solenoidal magnetic field with an integrated field strength of 1Tm. The recoil detector was installed in late 2005. After the commissioning of all components was finished in September 2006, it operated stably until the end of data taking at HERA end of June 2007. The present paper gives a brief overview of the physics processes of interest and the general detector design. The recoil detector components, their calibration, the momentum reconstruction of charged particles, and the event selection are described in detail. The paper closes with a summary of the performance of the detection system.

  19. Smile detectors correlation (United States)

    Yuksel, Kivanc; Chang, Xin; Skarbek, Władysław


    The novel smile recognition algorithm is presented based on extraction of 68 facial salient points (fp68) using the ensemble of regression trees. The smile detector exploits the Support Vector Machine linear model. It is trained with few hundreds exemplar images by SVM algorithm working in 136 dimensional space. It is shown by the strict statistical data analysis that such geometric detector strongly depends on the geometry of mouth opening area, measured by triangulation of outer lip contour. To this goal two Bayesian detectors were developed and compared with SVM detector. The first uses the mouth area in 2D image, while the second refers to the mouth area in 3D animated face model. The 3D modeling is based on Candide-3 model and it is performed in real time along with three smile detectors and statistics estimators. The mouth area/Bayesian detectors exhibit high correlation with fp68/SVM detector in a range [0:8; 1:0], depending mainly on light conditions and individual features with advantage of 3D technique, especially in hard light conditions.

  20. The HERMES recoil detector

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Aschenauer, E.C. [DESY, Zeuthen (Germany); Belostotski, S. [B.P. Konstantinov Petersburg Nuclear Physics Insitute, Gatchina (Russian Federation)] [and others; Collaboration: HERMES Recoil Detector Group


    For the final running period of HERA, a recoil detector was installed at the HERMES experiment to improve measurements of hard exclusive processes in charged-lepton nucleon scattering. Here, deeply virtual Compton scattering is of particular interest as this process provides constraints on generalised parton distributions that give access to the total angular momenta of quarks within the nucleon. The HERMES recoil detector was designed to improve the selection of exclusive events by a direct measurement of the four-momentum of the recoiling particle. It consisted of three components: two layers of double-sided silicon strip sensors inside the HERA beam vacuum, a two-barrel scintillating fibre tracker, and a photon detector. All sub-detectors were located inside a solenoidal magnetic field with an integrated field strength of 1Tm. The recoil detector was installed in late 2005. After the commissioning of all components was finished in September 2006, it operated stably until the end of data taking at HERA end of June 2007. The present paper gives a brief overview of the physics processes of interest and the general detector design. The recoil detector components, their calibration, the momentum reconstruction of charged particles, and the event selection are described in detail. The paper closes with a summary of the performance of the detection system.

  1. Detectors for Tomorrow's Instruments (United States)

    Moseley, Harvey


    Cryogenically cooled superconducting detectors have become essential tools for a wide range of measurement applications, ranging from quantum limited heterodyne detection in the millimeter range to direct searches for dark matter with superconducting phonon detectors operating at 20 mK. Superconducting detectors have several fundamental and practical advantages which have resulted in their rapid adoption by experimenters. Their excellent performance arises in part from reductions in noise resulting from their low operating temperatures, but unique superconducting properties provide a wide range of mechanisms for detection. For example, the steep dependence of resistance with temperature on the superconductor/normal transition provides a sensitive thermometer for calorimetric and bolometric applications. Parametric changes in the properties of superconducting resonators provides a mechanism for high sensitivity detection of submillimeter photons. From a practical point of view, the use of superconducting detectors has grown rapidly because many of these devices couple well to SQUID amplifiers, which are easily integrated with the detectors. These SQUID-based amplifiers and multiplexers have matured with the detectors; they are convenient to use, and have excellent noise performance. The first generation of fully integrated large scale superconducting detection systems are now being deployed. I will discuss the prospects for a new generation of instruments designed to take full advantage of the revolution in detector technology.

  2. A New Virtual Point Detector Concept for a HPGe detector

    International Nuclear Information System (INIS)

    Byun, Jong In; Yun, Ju Yong


    For last several decades, the radiation measurement and radioactivity analysis techniques using gamma detectors have been well established. Especially , the study about the detection efficiency has been done as an important part of gamma spectrometry. The detection efficiency depends strongly on source-to-detector distance. The detection efficiency with source-to-detector distance can be expressed by a complex function of geometry and physical characteristics of gamma detectors. In order to simplify the relation, a virtual point detector concept was introduced by Notea. Recently, further studies concerning the virtual point detector have been performed. In previous other works the virtual point detector has been considered as a fictitious point existing behind the detector end cap. However the virtual point detector position for the front and side of voluminous detectors might be different due to different effective central axis of them. In order to more accurately define the relation, therefore, we should consider the virtual point detector for the front as well as side and off-center of the detector. The aim of this study is to accurately define the relation between the detection efficiency and source-to-detector distance with the virtual point detector. This paper demonstrates the method to situate the virtual point detectors for a HPGe detector. The new virtual point detector concept was introduced for three area of the detector and its characteristics also were demonstrated by using Monte Carlo Simulation method. We found that the detector has three virtual point detectors except for its rear area. This shows that we should consider the virtual point detectors for each area when applying the concept to radiation measurement. This concept can be applied to the accurate geometric simplification for the detector and radioactive sources.

  3. 32x32 HgCdTe/CCD infrared camera for the 2-5 micron range

    International Nuclear Information System (INIS)

    Monin, J.L.; Vauglin, I.; Sibille, F.


    The paper presents a complete infrared camera system, based on a high electron capacity detector (HgCdTe/CCD), that has been used under high background conditions to generate astronomical images. The performance of the system and some results are presented, and the use of such a detector in astronomy is discussed. 8 references

  4. Development of transition edge superconducting bolometers for the SAFARI Far-Infrared spectrometer on the SPICA space-borne telescope

    NARCIS (Netherlands)

    Mauskopf, P.; Morozov, D.; Glowacka, D.; Goldie, D.; Withington, S.; Bruijn, M.; De Korte, P.; Hoevers, H.; Ridder, M.; Van der Kuur, J.; Gao, J.R.


    We describe the optimization of transition edge superconducting (TES) detectors for use in a far-infrared (FIR) Fourier transform spectrometer (FTS) mounted on a cryogenically cooled space-borne telescope (e.g. SPICA). The required noise equivalent power (NEP) of the detectors is approximately 10?19

  5. Detectors - Electronics; Detecteurs - Electronique

    Energy Technology Data Exchange (ETDEWEB)

    Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J. [Lab. de Physique Corpusculaire, Caen Univ., 14 (France)


    The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X {yields} e{sup -} converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the {sup 3}He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

  6. Quartz substrate infrared photonic crystal (United States)

    Ghadiri, Khosrow; Rejeb, Jalel; Vitchev, Vladimir N.


    This paper presents the fabrication of a planar photonic crystal (p2c) made of a square array of dielectric rods embedded in air, operating in the infrared spectrum. A quartz substrate is employed instead of the commonly used silicon or column III-V substrate. Our square structure has a normalized cylinder radius-to-pitch ratio of r/a = 0.248 and dielectric material contrast ɛr of 4.5. We choose a Z-cut synthetic quartz for its cut (geometry), and etching properties. Then a particular Z-axis etching process is employed in order to ensure the sharp-edged verticality of the rods and fast etching speed. We also present the computer simulations that allowed the establishment of the photonic band gaps (PBG) of our photonic crystal, as well as the actual measurements. An experimental measurement have been carried out and compared with different simulations. It was found that experimental results are in good agreement with different simulation results. Finally, a frequency selective device for optical communication based on the introduction of impurity sites in the photonic crystal is presented. With our proposed structure Optical System on a Chip (OsoC) with micro-cavity based active devices such as lasers, diodes, modulators, couplers, frequency selective emitters, add-drop filters, detectors, mux/demuxes and polarizers connected by passive waveguide links can be realized.

  7. Layered semiconductor neutron detectors (United States)

    Mao, Samuel S; Perry, Dale L


    Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

  8. Lithium germanium detectors reactivation

    International Nuclear Information System (INIS)

    Nicolai, J.A.; Marti, G.V.; Riso, J.M.; Gimenez, C.R.


    A convenient method to regenerate the characteristics of damaged Ge(li) detectors, that has been applied in the authors' laboratory, is described. The procedure consists in warming-up the crystal in its cryostat to temperatures between 10 deg C and 30 deg C above room temperature, in order to clean its surface. Subsequent cooling down to liquid nitrogen temperature, followed by one or more clean-up drifting processes, are applied to the crystals. This paper summarizes the results obtained with several detectors; this method was applied successfully to 15 detectors more. (author) [es

  9. The AGILE anticoincidence detector

    International Nuclear Information System (INIS)

    Perotti, F.; Fiorini, M.; Incorvaia, S.; Mattaini, E.; Sant'Ambrogio, E.


    AGILE is a γ-ray astrophysics space mission which will operate, starting from 2006, in the 30 MeV-50 GeV energy range with imaging capability also in the 15-45 keV energy band. In order to achieve the required detection sensitivity, all AGILE detectors are surrounded by an anticoincidence detector aimed at charged particle background rejection with an inefficiency as low as 10 -4 . In this work, the design and the structure of this anticoincidence detector are presented, as well as its performances in terms of charged particles detection inefficiency as derived from extensive calibrations performed at CERN PS

  10. Liquid ionizing radiaion detector

    International Nuclear Information System (INIS)

    deGaston, A.N.


    A normally nonconducting liquid such as liquid hydrocarbon is encased between a pair of electrodes in an enclosure so that when the liquid is subjected to ionizing radiation, the ion pairs so created measurably increase the conductivity of the fluid. The reduced impedance between the electrodes is detectable with a sensitive ohm-meter and indicates the amount of ionizing radiation. The enclosure, the electrodes and the fluid can be constructed of materials that make the response of the detector suitable for calibrating a large range of radiation energy levels. The detector is especially useful in medical applications where tissue equivalent X ray detectors are desired

  11. Ionization detectors, ch. 3

    International Nuclear Information System (INIS)

    Sevcik, J.


    Most measuring devices used in gas chromatography consist of detectors that measure the ionization current. The process is based on the collision of a moving high-energy particle with a target particle that is ionised while an electron is freed. The discussion of the conditions of the collision reaction, the properties of the colliding particles, and the intensity of the applied field point to a unified classification of ionisation detectors. Radioactive sources suitable for use in these detectors are surveyed. The slow-down mechanism, recombination and background current effect are discussed

  12. The Clover detector

    Energy Technology Data Exchange (ETDEWEB)

    Beck, F A; Byrski, Th; Durien, D; Duchene, G; France, G de; Kharraja, B; Wei, L [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Butler, P; Jones, G; Jones, P [Liverpool Univ. (United Kingdom). Oliver Lodge Lab.; Hannachi, F [Daresbury Lab. (United Kingdom)


    The EUROGAM Phase I device is almost running for experiments and new technical developments are in progress for its second phase. For example, a composite Ge detector should enable: a very large photopeak efficiency with good energy and timing resolutions; and, the covering, with Ge, of a large portion of 4{pi}-Str. The Clover detector, proposed by the CRN, Strasbourg, is one of this new generation of Ge detectors. It is currently developed in France by the EUROGAM collaboration. The design, the technical characteristics of the counter and the first results of the prototype tests are discussed in this contribution. (author). 1 ref., 2 tabs., 2 refs.

  13. Fuel rod leak detector

    International Nuclear Information System (INIS)

    Womack, R.E.


    A typical embodiment of the invention detects leaking fuel rods by means of a radiation detector that measures the concentration of xenon-133 ( 133 Xe) within each individual rod. A collimated detector that provides signals related to the energy of incident radiation is aligned with one of the ends of a fuel rod. A statistically significant sample of the gamma radiation (γ-rays) that characterize 133 Xe is accumulated through the detector. The data so accumulated indicates the presence of a concentration of 133 Xe appropriate to a sound fuel rod, or a significantly different concentration that reflects a leaking fuel rod

  14. The HOTWAXS detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E.; Derbyshire, G.E. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Diakun, G. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Duxbury, D.M. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)], E-mail:; Fairclough, J.P.A. [Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF (United Kingdom); Harvey, I.; Helsby, W.I. [Science and Technology Facilities Council, Daresbury Laboratory, Keckwick Lane, Daresbury, Warrington WA4 4AD (United Kingdom); Lipp, J.D.; Marsh, A.S.; Salisbury, J. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Sankar, G. [Royal Institution of GB, 21 Albemarle Street, London W1S 4BS (United Kingdom); Spill, E.J.; Stephenson, R. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Terrill, N.J. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom)


    The development and testing of the HOTWAXS position-sensitive X-ray detector for Synchrotron Radiation Sources is described. Funded from a facility development grant, the aim of the project was to produce a high counting rate, parallax-free photon counting detector to be used in the combined studies of X-ray absorption fine structure and X-ray diffraction (XAFS/XRD), and also in the technique of small angle and wide angle X-ray scattering (SAXS/WAXS). The detector system is described together with results of experiments carried out at the Daresbury Laboratory Synchrotron Radiation Source.

  15. The HOTWAXS detector

    International Nuclear Information System (INIS)

    Bateman, J.E.; Derbyshire, G.E.; Diakun, G.; Duxbury, D.M.; Fairclough, J.P.A.; Harvey, I.; Helsby, W.I.; Lipp, J.D.; Marsh, A.S.; Salisbury, J.; Sankar, G.; Spill, E.J.; Stephenson, R.; Terrill, N.J.


    The development and testing of the HOTWAXS position-sensitive X-ray detector for Synchrotron Radiation Sources is described. Funded from a facility development grant, the aim of the project was to produce a high counting rate, parallax-free photon counting detector to be used in the combined studies of X-ray absorption fine structure and X-ray diffraction (XAFS/XRD), and also in the technique of small angle and wide angle X-ray scattering (SAXS/WAXS). The detector system is described together with results of experiments carried out at the Daresbury Laboratory Synchrotron Radiation Source

  16. Semiconductor ionizino. radiation detectors

    International Nuclear Information System (INIS)


    Spectrometric semiconductor detectors of ionizing radiation with the electron-hole junction, based on silicon and germanium are presented. The following parameters are given for the individual types of germanium detectors: energy range of detected radiation, energy resolution given as full width at half maximum (FWHM) and full width at one tenth of maximum (FWTM) for 57 Co and 60 Co, detection sensitivity, optimal voltage, and electric capacitance at optimal voltage. For silicon detectors the value of FWHM for 239 Pu is given, the sensitive area and the depth of the sensitive area. (E.S.)

  17. Microfluidic Scintillation Detectors

    CERN Multimedia

    Microfluidic scintillation detectors are devices of recent introduction for the detection of high energy particles, developed within the EP-DT group at CERN. Most of the interest for such technology comes from the use of liquid scintillators, which entails the possibility of changing the active material in the detector, leading to an increased radiation resistance. This feature, together with the high spatial resolution and low thickness deriving from the microfabrication techniques used to manufacture such devices, is desirable not only in instrumentation for high energy physics experiments but also in medical detectors such as beam monitors for hadron therapy.

  18. Training detector as simulator of alpha detector

    International Nuclear Information System (INIS)

    Tirosh, D.; Duvniz, E.; Assido, H.; Barak, D.; Paran, J.


    Alpha contamination is a common phenomena in radiation research laboratories and other sites. Training staff to properly detect and control alpha contamination, present special problems. In order to train health physics personnel, while using alpha sources, both the trainers and the trainees are inevitably exposed to alpha contamination. This fact of course, comes in conflict with safety principles. In order to overcome these difficulties, a training detector was developed, built and successfully tested. (authors)

  19. Multi electrode semiconductors detectors

    CERN Document Server

    Amendolia, S R; Bertolucci, Ennio; Bosisio, L; Bradaschia, C; Budinich, M; Fidecaro, F; Foà, L; Focardi, E; Giazotto, A; Giorgi, M A; Marrocchesi, P S; Menzione, A; Ristori, L; Rolandi, Luigi; Scribano, A; Stefanini, A; Vincelli, M L


    Detectors with very high space resolution have been built in this laboratory and tested at CERN in order to investigate their possible use in high energy physics experiments. These detectors consist of thin layers of silicon crystals acting as ionization chambers. Thin electrodes, structured in strips or in more fancy shapes are applied to their surfaces by metal coating. The space resolution which could be reached is of the order of a few microns. An interesting feature of these solid state detectors is that they can work under very high or low external pressure or at very low temperature. The use of these detectors would strongly reduce the dimensions and the cost of high energy experiments. (3 refs).

  20. Multi electrode semiconductor detectors

    International Nuclear Information System (INIS)

    Amendolia, S.R.; Batignani, G.; Bertolucci, E.; Bosisio, L.; Budinich, M.; Bradaschia, C.; Fidecaro, F.; Foa, L.; Focardi, E.; Giazotto, A.; Giorgi, M.A.; Marrocchesi, P.S.; Menzione, A.; Ristori, L.; Rolandi, L.; Scribano, A.; Stefanini, A.; Vincelli, M.L.


    Detectors with very high space resolution have been built in the laboratory and tested at CERN in order to investigate their possible use in high energy physics experiments. These detectors consist of thin layers of silicon crystals acting as ionization chambers. Thin electrodes, structured in strips or in more fancy shapes are applied to their surfaces by metal coating. The space resolution which could be reached is of the order of a few microns. An interesting feature of these solid state detectors is that they can work under very high or low external pressure or at very low temperature. The use of these detectors would strongly reduce the dimensions and the cost of high energy experiments. (Auth.)

  1. Inverter ratio failure detector (United States)

    Wagner, A. P.; Ebersole, T. J.; Andrews, R. E. (Inventor)


    A failure detector which detects the failure of a dc to ac inverter is disclosed. The inverter under failureless conditions is characterized by a known linear relationship of its input and output voltages and by a known linear relationship of its input and output currents. The detector includes circuitry which is responsive to the detector's input and output voltages and which provides a failure-indicating signal only when the monitored output voltage is less by a selected factor, than the expected output voltage for the monitored input voltage, based on the known voltages' relationship. Similarly, the detector includes circuitry which is responsive to the input and output currents and provides a failure-indicating signal only when the input current exceeds by a selected factor the expected input current for the monitored output current based on the known currents' relationship.

  2. Sensitive detectors in HPLC

    International Nuclear Information System (INIS)



    Detection of sample components in HPLC is difficult for many reasons; the key difficulty is the mobile phase which usually has properties similar to the solute. A variety of detectors have been developed for use in HPLC based on one of the above approaches; however, the search is still continuing for an ideal or universal detector. A universal detector should have the following characteristics: (1) responds to all solutes or has predictable specificity; (2) high detectability and the same predictable response; (3) fast response; (4) wide range of linearity; (5) unaffected by changes in temperature and mobile-phase flow; (6) responds independently of the mobile phase; (7) makes no contribution to extracolumn band broadening; (8) reliable and convenient to use; (9) nondestructive to the solute; (10) provides qualitative information on the detected peak. Unfortunately, no available HPLC detector possesses all these properties. 145 refs

  3. OPAL detector electromagnetic calorimeter

    CERN Multimedia


    Half of the electromagnetic calorimeter of the OPAL detector is seen in this photo. This calorimeter consists of 4720 blocks of lead glass. It was used to detect and measure the energy of photons, electrons and positrons by absorbing them.

  4. Accurate and independent spectral response scale based on silicon trap detectors and spectrally invariant detectors

    International Nuclear Information System (INIS)

    Gran, Jarle


    The study aims to establish an independent high accuracy spectral response scale over a broad spectral range based on standard laboratory equipment at a moderate cost. This had to be done by a primary method, where the responsivity of the detector is linked to fundamental constants. Summary, conclusion and future directions: In this thesis it has been demonstrated that an independent spectral response scale from the visual to the IR based on simple relative measurements can be established. The accuracy obtained by the hybrid self-calibration method demonstrates that state of the art accuracy is obtained with self-calibration principles. A calculable silicon trap detector with low internal losses over a wide spectral range is needed to establish the scale, in addition to a linear, spectrally independent detector with a good signal to noise ratio. By fitting the parameters in the responsivity model to a purely relative measurement we express the spectral response in terms of fundamental constants with a known uncertainty This is therefore a primary method. By applying a digital filter on the relative measurements of the InGaAs detectors in the infrared reduces the standard deviation by 30 %. In addition, by optimising the necessary scaling constant converting the relative calibration to absolute values, we have managed to establish an accurate and cost efficient spectral response scale in the IR. The full covariance analysis, which takes into account the correlation in the absolute values of the silicon detector, the correlation caused by the filter and the scaling constant, shows that the spectral response scale established in the infrared with InGaAs detectors is done with high accuracy. A similar procedure can be used in the UV, though it has not been demonstrated here. In fig. 10 the responsitivities of the detectors (a) and their associated uncertainties (b) at the 1 sigma level of confidence is compared for the three publications. We see that the responsivity

  5. Detector Control System for the ATLAS Forward Proton detector

    CERN Document Server

    Czekierda, Sabina; The ATLAS collaboration


    The ATLAS Forward Proton (AFP) is a forward detector using a Roman Pot technique, recently installed in the LHC tunnel. It is aiming at registering protons that were diffractively or electromagnetically scattered in soft and hard processes. Infrastructure of the detector consists of hardware placed both in the tunnel and in the control room USA15 (about 330 meters from the Roman Pots). AFP detector, like the other detectors of the ATLAS experiment, uses the Detector Control System (DCS) to supervise the detector and to ensure its safe and coherent operation, since the incorrect detector performance may influence the physics results. The DCS continuously monitors the detector parameters, subset of which is stored in data bases. Crucial parameters are guarded by alarm system. A detector representation as a hierarchical tree-like structure of well-defined subsystems built with the use of the Finite State Machine (FSM) toolkit allows for overall detector operation and visualization. Every node in the hierarchy is...

  6. New detector techniques

    CERN Document Server

    Iarocci, Enzo


    The intense R&D effort being carried out in view of LHC has given rise in a relatively short time to a wide spectrum of new detector concepts and technologies. Subject of the lectures will be some of the most interesting new ideas and developments, in the field of noble liquid, crystal and scintillating fiber trackers. The emphasis will be on the basic aspects of detector operation.

  7. The Micro Wire Detector

    International Nuclear Information System (INIS)

    Adeva, B.; Gomez, F.; Pazos, A.; Pfau, R.; Plo, M.; Rodriguez, J.M.; Vazquez, P.; Labbe, J.C.


    We present the performance of a new proportional gas detector. Its geometry consists of a cathode plane with 70x70 μm 2 apertures, crossed by 25 μm anode strips to which it is attached by 50 μm kapton spacers. In the region where the avalanche takes place, the anode strips are suspended in the gas mixture as in a standard wire chamber. This detector exhibits high rate capability and large gains, introducing very little material. (author)

  8. Calibration of germanium detectors

    International Nuclear Information System (INIS)

    Bjurman, B.; Erlandsson, B.


    This paper describes problems concerning the calibration of germanium detectors for the measurement of gamma-radiation from environmental samples. It also contains a brief description of some ways of reducing the uncertainties concerning the activity determination. These uncertainties have many sources, such as counting statistics, full energy peak efficiency determination, density correction and radionuclide specific-coincidence effects, when environmental samples are investigated at close source-to-detector distances

  9. Lepton detector workshop summary

    International Nuclear Information System (INIS)

    Imlay, R.; Iwata, S.; Thorndike, A.


    The study group met from June 7 to 11, 1976, with the dual purpose of reviewing an earlier Lepton Detector report in order to resolve some of the remaining design problems and of considering possible alternatives. Since the role of this group was primarily that of providing a critique of the earlier work, the reader is referred to that earlier paper for the general motivation and design of the detector. Problems studied at this session are described

  10. Liquid xenon detector engineering

    International Nuclear Information System (INIS)

    Chen, E.; Chen, M.; Gaudreau, M.P.J.; Montgomery, D.B.; Pelly, J.D.; Shotkin, S.; Sullivan, J.D.; Sumorok, K.; Yan, X.; Zhang, X.; Lebedenko, V.


    The design, engineering constraints and R and D status of a 15 m 3 precision liquid xenon, electromagnetic calorimeter for the Superconducting Super Collider are discussed in this paper. Several prototype liquid xenon detectors have been built, and preliminary results are described. The design of a conical 7 cell by 7 cell detector capable of measuring fully contained high energy electron showers is described in detail

  11. The LUCID-2 Detector

    CERN Document Server

    Sbarra, Carla; The ATLAS collaboration


    LUCID-2 (LUminosity Cherenkov Integrating Detector) is the upgrade of the main detector dedicated to luminosity measurements in ATLAS. Most changes were motivated by the number of interactions per bunch-crossing and the 25 ns bunch-spacing expected in LHC RUN II (2015-2018). Both fast online information used by LHC for luminosity optimisation and levelling in ATLAS, and per-bunch data to be used offline, come from LUCID-2

  12. FERMILAB: Collider detectors -2

    International Nuclear Information System (INIS)



    Last month's edition (April, page 12) included a status report on data collection and preliminary physics results from the 'newcomer' DO detector at Fermilab's Tevatron proton-antiproton collider. This time the spotlight falls in the Veteran' CDF detector, in action since 1985 and meanwhile significantly upgraded. Meanwhile the Tevatron collider continues to improve, with record collision rates

  13. Microsonic detector (MSD)

    International Nuclear Information System (INIS)

    Bober, J.T.; Haridas, P.; Oh, S.H.; Pless, I.A.; Stoughton, T.B.


    The microsonic detector (MSD) has good spatial resolution, moderate flux capacity, moderate event rate, and small volume. The MSD is a super clean bubble chamber driven at 10-50 KHz. It would be used in experiments as a vertex detector to detect short lived particles. Its characteristics--active volume, density, absorption length, radiation length, and spatial resolution--are given. The setup is schematicized, and a photograph of a 130 MeV/C photon bremsstrahlung beam is given

  14. Development of the infrared instrument for gas detection (United States)

    Chen, Ching-Wei; Chen, Chia-Ray


    MWIR (Mid-Wave Infrared) spectroscopy shows a large potential in the current IR devices market, due to its multiple applications, such as gas detection, chemical analysis, industrial monitoring, combustion and flame characterization. It opens this technique to the fields of application, such as industrial monitoring and control, agriculture and environmental monitoring. However, a major barrier, which is the lack of affordable specific key elements such a MWIR light sources and low cost uncooled detectors, have held it back from its widespread use. In this paper an uncooled MWIR detector combined with image enhancement technique is reported. This investigation shows good results in gas leakage detection test. It also verify the functions of self-developed MWIR lens and optics. A good agreement in theoretical design and experiment give us the lessons learned for the potential application in infrared satellite technology. A brief discussions will also be presented in this paper.

  15. A Photovoltaic InAs Quantum-Dot Infrared Photodetector

    International Nuclear Information System (INIS)

    Guang-Hua, Tang; Bo, Xu; Li-Wen, Jiang; Jin-Xia, Kong; Ning, Kong; De-Chun, Liang; Ping, Liang; Xiao-Ling, Ye; Peng, Jin; Feng-Qi, Liu; Yong-Hai, Chen; Zhan-Guo, Wang


    A photovoltaic quantum dot infrared photodetector with InAs/GaAs/AlGaAs structures is reported. The detector is sensitive to normal incident light. At zero bias and 78K, a clear spectral response in the range of 2–7 μm has been obtained with peaks at 3.1, 4.8 and 5.7 μm. The bandgap energies of GaAs and Alo.2Gao.sAs at 78K are calculated and the energy diagram of the transitions in the Quantum-Dot Infrared Photodetector (QDIP) is given out. The photocurrent signals can be detected up to 110K, which is state-of-the-art for photovoltaic QDIP. The photovoltaic effect in our detector is a result of the enhanced band asymmetry as we design in the structure

  16. Characteristics of radiation temperature and radiosity coefficient by means of infrared radiometer. Sekigai hoshakei ni yoru zairyo hyomen no hosha tokusei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Y; Kaminaga, F [Ibaraki University, Ibaraki (Japan). Faculty of Engineering; Ishii, T; Sato, K [Ibaraki University, Ibaraki (Japan); Kurokawa, T [NEC San-ei Instrumentsu Ltd., Tokyo (Japan)


    A radiation thermometer was applied to the measurement and analysis of radiation temperature of the material surface. In this paper, the characteristics of the radiation temperature and the radiosity coefficient of gray body materials are investigatied. An infrared radiometer was used, which detects radiation energy in the region between 8 and 13{mu}m of wavelength. This infared radiometer has a Hg-Cd-Te photon radiation sensor. The variation of emissivity was measured for the four kinds of non-metalic materials, i.e., graphite, carbon fiber composite, Si-SiC ceramic, and black paint spread on an aluminum plate. As a result, the relationship between material temperature and radiation energy was made clear. Furthermore, the space-dependent variation of the radiation temperature and the radiosity coefficient was derived from the two-dimensional CRT image of the infrared radiometer. Consequently, the emmisivity variation gave a maximum for the carbon fiber composite surface rich in irregularity, and decreased in the order of graphite, Si-SiC, and black paint. 7 refs., 15 figs.

  17. Protecting detectors in ALICE

    International Nuclear Information System (INIS)

    Lechman, M.; Augustinus, A.; Chochula, P.; Di Mauro, A.; Stig Jirden, L.; Rosinsky, P.; Schindler, H.; Cataldo, G. de; Pinazza, O.; Kurepin, A.; Moreno, A.


    ALICE (A Large Ion Collider Experiment) is one of the big LHC (Large Hadron Collider) experiments at CERN in Geneva. It is composed of many sophisticated and complex detectors mounted very compactly around the beam pipe. Each detector is a unique masterpiece of design, engineering and construction and any damage to it could stop the experiment for months or even for years. It is therefore essential that the detectors are protected from any danger and this is one very important role of the Detector Control System (DCS). One of the main dangers for the detectors is the particle beam itself. Since the detectors are designed to be extremely sensitive to particles they are also vulnerable to any excess of beam conditions provided by the LHC accelerator. The beam protection consists of a combination of hardware interlocks and control software and this paper will describe how this is implemented and handled in ALICE. Tools have also been developed to support operators and shift leaders in the decision making related to beam safety. The gained experiences and conclusions from the individual safety projects are also presented. (authors)

  18. Radiation detectors for reactors

    International Nuclear Information System (INIS)

    Balagi, V.


    Detection and measurement of radiation plays a vital role in nuclear reactors from the point of view of control and safety, personnel protection and process control applications. Various types of radiation are measured over a wide range of intensity. Consequently a variety of detectors find use in nuclear reactors. Some of these devices have been developed in Electronics Division. They include gas-filled detectors such as 10 B-lined proportional counters and chambers, fission detectors and BF 3 counters are used for the measurement of neutron flux both for reactor control and safety, process control as well as health physics instrumentation. In-core neutron flux instrumentation employs the use detectors such as miniature fission detectors and self-powered detectors. In this development effort, several indigenous materials, technologies and innovations have been employed to suit the specific requirement of nuclear reactor applications. This has particular significance in view of the fact that several new types of reactors such as P-4, PWR and AHWR critical facilities, FBTR, PFBR as well as the refurbishment of old units like CIRUS are being developed. The development work has sought to overcome some difficulties associated with the non-availability of isotopically enriched neutron-sensing materials, achieving all-welded construction etc. The present paper describes some of these innovations and performance results. (author)

  19. Detectors for CBA

    International Nuclear Information System (INIS)

    Baggett, N.; Gordon, H.A.; Palmer, R.B.; Tannenbaum, M.J.


    We discuss some current approaches to a large solid angle detector. An alternative approach for utilizing the high rate of events at CBA is to design special purpose detectors for specific physics goals which can be pursued within a limited solid angle. In many cases this will be the only way to proceed, and then high luminosity has a different significance. The total rate in the restricted acceptance is less likely to be a problem, while the need for high luminosity to obtain sufficient data is obvious. Eight such experiments from studies carried out in the community are surveyed. Such experiments could be run on their own or in combination with others at the same intersection, or even with a large solid angle detector, if a window can be provided in the larger facility. The small solid angle detector would provide the trigger and special information, while the facility would provide back-up information on the rest of the event. We consider some possibilities of refurbishing existing detectors for use at CBA. This discussion is motivated by the fact that there is a growing number of powerful detectors at colliding beam machines around the world. Their builders have invested considerable amounts of time, money and ingenuity in them, and may wish to extend the useful lives of their creations, as new opportunities arise

  20. GANIL beam profile detectors

    International Nuclear Information System (INIS)

    Tribouillard, C.


    In the design phase of GANIL which started in 1977, one of the priorities of the project management was equipping the beamlines with a fast and efficient system for visualizing the beam position, thus making possible adjustment of the beam transport lines optics and facilitating beam control. The implantation of some thirty detectors was foreseen in the initial design. The assembly of installed detectors (around 190) proves the advantages of these detectors for displaying all the beams extracted from GANIL: transfer and transport lines, beam extracted from SISSI, very high intensity beam, secondary ion beams from the production target of the LISE and SPEG spectrometers, different SPIRAL project lines. All of these detectors are based on standard characteristics: - standard flange diameter (DN 160) with a standard booster for all the sensors; - identical analog electronics for all the detectors, with networking; - unique display system. The new micro-channel plate non-interceptive detectors (beam profile and ion packet lengths) make possible in-line control of the beam quality and accelerator stability. (author)

  1. Basic Radiation Detectors. Chapter 6

    Energy Technology Data Exchange (ETDEWEB)

    Van Eijk, C. W.E. [Faculty of Applied Sciences, Delft University of Technology, Delft (Netherlands)


    Radiation detectors are of paramount importance in nuclear medicine. The detectors provide a wide range of information including the radiation dose of a laboratory worker and the positron emission tomography (PET) image of a patient. Consequently, detectors with strongly differing specifications are used. In this chapter, general aspects of detectors are discussed.

  2. Frontier detectors for frontier physics

    International Nuclear Information System (INIS)

    Cervelli, F.; Scribano, A.


    These proceedings contain the articles presented at the named meeting. These concern developments of radiation detectors and counting techniques in high energy physics. Especially considered are tracking detectors, calorimeters, time projection chambers, detectors for rare events, solid state detectors, particle identification, and optical readout systems. See hints under the relevant topics. (HSI)

  3. The ALICE forward multiplicity detector

    DEFF Research Database (Denmark)

    Holm Christensen, Christian; Gulbrandsen, Kristjan; Sogaard, Carsten


    The ALICE Forward Multiplicity Detector (FMD) is a silicon strip detector with 51,200 strips arranged in 5 rings, covering the range $-3.4......The ALICE Forward Multiplicity Detector (FMD) is a silicon strip detector with 51,200 strips arranged in 5 rings, covering the range $-3.4...

  4. Progress in semiconductor drift detectors

    International Nuclear Information System (INIS)

    Rehak, P.; Walton, J.; Gatti, E.


    Progress in testing semiconductor drift detectors is reported. Generally better position and energy resolutions were obtained than resolutions published previously. The improvement is mostly due to new electronics better matched to different detectors. It is shown that semiconductor drift detectors are becoming versatile and reliable detectors for position and energy measurements

  5. Infrared source test

    Energy Technology Data Exchange (ETDEWEB)

    Ott, L.


    The purpose of the Infrared Source Test (IRST) is to demonstrate the ability to track a ground target with an infrared sensor from an airplane. The system is being developed within the Advance Technology Program`s Theater Missile Defense/Unmanned Aerial Vehicle (UAV) section. The IRST payload consists of an Amber Radiance 1 infrared camera system, a computer, a gimbaled mirror, and a hard disk. The processor is a custom R3000 CPU board made by Risq Modular Systems, Inc. for LLNL. The board has ethernet, SCSI, parallel I/O, and serial ports, a DMA channel, a video (frame buffer) interface, and eight MBytes of main memory. The real-time operating system VxWorks has been ported to the processor. The application code is written in C on a host SUN 4 UNIX workstation. The IRST is the result of a combined effort by physicists, electrical and mechanical engineers, and computer scientists.

  6. Detectors on the drawing board

    CERN Document Server

    Katarina Anthony


    Linear collider detector developers inside and outside CERN are tackling the next generation of detector technology. While their focus has centred on high-energy linear collider detectors, their innovative concepts and designs will be applicable to any future detector.   A simulated event display in one of the new generation detectors. “While the LHC experiments remain the pinnacle of detector technology, you may be surprised to realise that the design and expertise behind them is well over 10 years old,” says Lucie Linssen, CERN’s Linear Collider Detector (LCD) project manager whose group is pushing the envelope of detector design. “The next generation of detectors will have to surpass the achievements of the LHC experiments. It’s not an easy task but, by observing detectors currently in operation and exploiting a decade’s worth of technological advancements, we’ve made meaningful progress.” The LCD team is curr...

  7. Powerful infrared emitting diodes

    Directory of Open Access Journals (Sweden)

    Kogan L. M.


    Full Text Available Powerful infrared LEDs with emission wavelength 805 ± 10, 870 ± 20 and 940 ± 10 nm developed at SPC OED "OPTEL" are presented in the article. The radiant intensity of beam diode is under 4 W/sr in the continuous mode and under 100 W/sr in the pulse mode. The radiation power of wide-angle LEDs reaches 1 W in continuous mode. The external quantum efficiency of emission IR diodes runs up to 30%. There also has been created infrared diode modules with a block of flat Fresnel lenses with radiant intensity under 70 W/sr.

  8. Fine-scale spatial response of CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Brunett, B.A.; Van Scyoc, J.M.; Hilton, N.R.; Lund, J.C.; James, R.B.; Schlesinger, T.E.


    Several studies have suggested that the uniformity of Cadmium Zinc Telluride (CZT) detectors play an important role in their performance when operated as gamma-ray spectrometers. However the detailed gamma response of simple planar detectors as a function of position over the device area is largely unknown. To address this issue the authors have built a system capable of measuring the detector response with a resolution of ∼250 (micro)m. The system consists of a highly collimated (∼200 (micro)m) photon source (<150 kev) scanned over the detector using a computer controlled two-axis translation stage. Fifteen samples configured as planar detectors were examined with the new apparatus. The material grade of the detectors examined varied from counter to select discriminator. Two classes of spatial response variation were observed and are presented here. Infrared (IR) transmission images were also acquired for each sample and correlation between features in the pulse height spectrum and crystalline defects were observed

  9. Far infrared through millimeter backshort-under-grid arrays (United States)

    Allen, Christine A.; Abrahams, John; Benford, Dominic J.; Chervenak, James A.; Chuss, David T.; Staguhn, Johannes G.; Miller, Timothy M.; Moseley, S. Harvey; Wollack, Edward J.


    We are developing a large-format, versatile, bolometer array for a wide range of infrared through millimeter astronomical applications. The array design consists of three key components - superconducting transition edge sensor bolometer arrays, quarter-wave reflective backshort grids, and Superconducting Quantum Interference Device (SQUID) multiplexer readouts. The detector array is a filled, square grid of bolometers with superconducting sensors. The backshort arrays are fabricated separately and are positioned in the etch cavities behind the detector grid. The grids have unique three-dimensional interlocking features micromachined into the walls for positioning and mechanical stability. The ultimate goal of the program is to produce large-format arrays with background-limited sensitivity, suitable for a wide range of wavelengths and applications. Large-format (kilopixel) arrays will be directly indium bump bonded to a SQUID multiplexer circuit. We have produced and tested 8×8 arrays of 1 mm detectors to demonstrate proof of concept. 8×16 arrays of 2 mm detectors are being produced for a new Goddard Space Flight Center instrument. We have also produced models of a kilopixel detector grid and dummy multiplexer chip for bump bonding development. We present detector design overview, several unique fabrication highlights, and assembly technologies.

  10. Detectors for proton counting. Si-APD and scintillation detectors

    International Nuclear Information System (INIS)

    Kishimoto, Shunji


    Increased intensity of synchrotron radiation requests users to prepare photon pulse detectors having higher counting rates. As detectors for photon counting, silicon-avalanche photodiode (Si-APD) and scintillation detectors were chosen for the fifth series of detectors. Principle of photon detection by pulse and need of amplification function of the detector were described. Structure and working principle, high counting rate measurement system, bunch of electrons vs. counting rate, application example of NMR time spectroscopy measurement and comments for users were described for the Si-APD detector. Structure of scintillator and photomultiplier tube, characteristics of scintillator and performance of detector were shown for the NaI detector. Future development of photon pulse detectors was discussed. (T. Tanaka)

  11. Magnesium borate radiothermoluminescent detectors

    International Nuclear Information System (INIS)

    Kazanskaya, V.A.; Kuzmin, V.V.; Minaeva, E.E.; Sokolov, A.D.


    In the report the technology of obtaining polycrystalline magnesium borate activated by dysprosium is described briefly and the method of preparing the tabletted detectors from it is presented. The dependence of the light sum of the samples on the proportion of the components and on the sintering regime has shown that the most sensitive material is obtained at the proportion of boric anhydride and magnesium oxide 2.2-2.4 and at the dysprosium concentration about 1 milligram-atom per gram molecule of the base. The glow curve of such a material has a simple form with one peak the maximum of which is located at 190-200 0 C. The measurement of the main dosimetric characteristics of the magnesium borate tabletted detectors and the comparison with similar parmaeters of the lithium fluoride tabletted detectors have shown that at practically identical effective number the former detectors have the following substantial advantages: the sensitivity is ten-twenty times as large, they are substantially more technological on synthesis of the radiothermoluminophor and during the production of the tabletted detectors, they have a simple glow curve, they do not require the utilization of the thermocycling during the use. (author)

  12. HPGe detector shielding adjustment

    International Nuclear Information System (INIS)

    Trnkova, L.; Rulik, P.


    Low-level background shielding of HPGe detectors is used mainly for environmental samples with very low content of radionuclides. National Radiation Protection Institute (SURO) in Prague is equipped with 14 HPGe detectors with relative efficiency up to 150%. The detectors are placed in a room built from materials with low content of natural radionuclides and equipped with a double isolation of the floor against radon. Detectors themselves are placed in lead or steel shielding. Steel shielding with one of these detectors with relative efficiency of 100% was chosen to be rebuilt to achieve lower minimum detectable activity (MDA). Additional lead and copper shielding was built up inside the original steel shielding to reduce the volume of the inner space and filled with nitrogen by means of evaporating liquid nitrogen. The additional lead and copper shielding, consequent reduction of the inner volume and supply of evaporated nitrogen, caused a decrease of the background count and accordingly MDA values as well. The effect of nitrogen evaporation on the net areas of peaks belonging to radon daughters is significant. The enhanced shielding adjustment has the biggest influence in low energy range, what can be seen in collected data. MDA values in energy range from 30 keV to 400 keV decreased to 0.65-0.85 of original value, in energy range from 400 keV to 2 MeV they fell to 0.70-0.97 of original value. (authors)

  13. ATLAS muon detector

    CERN Multimedia

    Muon detectors from the outer layer of the ATLAS experiment at the Large Hadron Collider. Over a million individual detectors combine to make up the outer layer of ATLAS. All of this is exclusively to track the muons, the only detectable particles to make it out so far from the collision point. How the muon’s path curves in the magnetic field depends on how fast it is travelling. A fast muon curves only a very little, a slower one curves a lot. Together with the calorimeters, the muon detectors play an essential role in deciding which collisions to store and which to ignore. Certain signals from muons are a sure sign of exciting discoveries. To make sure the data from these collisions is not lost, some of the muon detectors react very quickly and trigger the electronics to record. The other detectors take a little longer, but are much more precise. Their job is to measure exactly where the muons have passed, calculating the curvature of their tracks in the magnetic field to the nearest five hundredths of a ...

  14. Lepton detector workshop summary

    International Nuclear Information System (INIS)

    Imlay, R.; Iwata, S.; Jacobs, S.


    A discussion is given of the initial detector design, focusing on the cost estimates and on the inner detector modules. With regard to inner modules, the rate problem was examined for the closest elements, and the question whether one should use argon or lead-liquid scintillator calorimeters was discussed. New designs which involved major modifications to the lepton detector are considered. The major motivations for alternative designs were twofold. One was that the original detector looked quite expensive, and a study of the tradeoff of money versus physics had not really been done yet. The second point was that, since the physics region to be explored was totally new ground, one would like to leave as many options open as possible and build a detector that was as flexible as possible. A scaled-down version of the original design, which was strongly favored by this study, appears to save an appreciable amount of money with a small decrease in the initial physics scope. The more modular designs seem quite attractive, but not enough time was spent to demonstrate feasibility

  15. The infrared retina

    International Nuclear Information System (INIS)

    Krishna, Sanjay


    As infrared imaging systems have evolved from the first generation of linear devices to the second generation of small format staring arrays to the present 'third-gen' systems, there is an increased emphasis on large area focal plane arrays (FPAs) with multicolour operation and higher operating temperature. In this paper, we discuss how one needs to develop an increased functionality at the pixel level for these next generation FPAs. This functionality could manifest itself as spectral, polarization, phase or dynamic range signatures that could extract more information from a given scene. This leads to the concept of an infrared retina, which is an array that works similarly to the human eye that has a 'single' FPA but multiple cones, which are photoreceptor cells in the retina of the eye that enable the perception of colour. These cones are then coupled with powerful signal processing techniques that allow us to process colour information from a scene, even with a limited basis of colour cones. Unlike present day multi or hyperspectral systems, which are bulky and expensive, the idea would be to build a poor man's 'infrared colour' camera. We use examples such as plasmonic tailoring of the resonance or bias dependent dynamic tuning based on quantum confined Stark effect or incorporation of avalanche gain to achieve embodiments of the infrared retina.

  16. The benefit of limb cloud imaging for infrared limb sounding of tropospheric trace gases


    G. Heinemann; P. Preusse; R. Spang; S. Adams


    Advances in detector technology enable a new generation of infrared limb sounders to measure 2-D images of the atmosphere. A proposed limb cloud imager (LCI) mode will detect clouds with a spatial resolution unprecedented for limb sounding. For the inference of temperature and trace gas distributions, detector pixels of the LCI have to be combined into super-pixels which provide the required signal-to-noise and information content for the retrievals. This study examines the extent to which tr...

  17. History of British infrared astronomy since the Second World War

    International Nuclear Information System (INIS)

    Jennings, R.E.


    In this review, the author describes the development of British infrared astronomy, from its beginnings around 1960 to the present time. The paper outlines the various techniques available and the different wavelength ranges which can be covered by these techniques e.g. balloons, mountain-based telescopes, the AAT in Australia, the 60-inch flux-collector on Tenerife, and the UKIRT telescope on Hawaii, and finally the IRAS satellite. The main groups involved in the British infrared work are UCL, Imperial College, and QMC, together with cooperative programmes with the Netherlands and the USA. The scientific results which have been obtained with these installations include studies of the relict radiation, HII regions, thermal radiation from dust and grains, and a dust shell around the star Vega, to mention but a few, interferometry, photometry and spectroscopy are also discussed, as in the long awaited development of infrared detector arrays. (UK)

  18. Spectral classification by the near infrared photometric parameters

    International Nuclear Information System (INIS)

    Tignanelli, H.L.; Feinstein, A.


    From the analysis of the measurements of KM-type stars done in the near infrared (1 to 3.5 microns: the JHKL bands of Johnsons's system), with an 83 cm reflector and a PbS detector at La Plata Observatory, we try to establish a new photometric classification system that discriminates luminosity class by means of certain parameters defined by infrared colours and infrared magnitudes. Data compiled and homogenized by J.Koornneef of southern bright stars in those bands were also included. The results give us information about the spectral types and reddening of those stars. We also indicate how to calculate the radiation excess that those stars could have. (author)

  19. Biological infrared microspectroscopy at the National Synchrotron Light Source

    International Nuclear Information System (INIS)

    Miller, Lisa M.; Carr, G. Lawrence; Williams, Gwyn P.; Sullivan, Michael; Chance, Mark R.


    Beamline U2B at the National Synchrotron Light Source has been designed and built as an infrared beamline dedicated to the study of biomedical problems. In 1997, the horizontal and vertical acceptances of Beamline U2B were increased in order to increase the overall flux of the beamline. A wedged, CVD diamond window separates the UHV vacuum of the VUV ring from the rough vacuum of the beamline. The endstation consists of a Nicolet Magna 860 step-scan FTIR and a NicPlan infrared microscope. The spectrometer is equipped with beamsplitter/detector combinations that permit data collection in the mid-and far-infrared regions. We have also made provisions for mounting an external detector (e.g. bolometer) for far infrared microspectroscopy. Thus far, Beamline U2B has been used to (1) perform chemical imaging of bone tissue and brain cells to address issues related to bone disease and epilepsy, respectively, and (2) examine time-resolved protein structure in the sub-millisecond folding of cytochrome c

  20. Automated vehicle detection in forward-looking infrared imagery. (United States)

    Der, Sandor; Chan, Alex; Nasrabadi, Nasser; Kwon, Heesung


    We describe an algorithm for the detection and clutter rejection of military vehicles in forward-looking infrared (FLIR) imagery. The detection algorithm is designed to be a prescreener that selects regions for further analysis and uses a spatial anomaly approach that looks for target-sized regions of the image that differ in texture, brightness, edge strength, or other spatial characteristics. The features are linearly combined to form a confidence image that is thresholded to find likely target locations. The clutter rejection portion uses target-specific information extracted from training samples to reduce the false alarms of the detector. The outputs of the clutter rejecter and detector are combined by a higher-level evidence integrator to improve performance over simple concatenation of the detector and clutter rejecter. The algorithm has been applied to a large number of FLIR imagery sets, and some of these results are presented here.