检索结果-内蒙古大学图书馆

infrared and photoelectronic imagers and detector devices

作者： Li, J. Choi, K.K. Tsui, D.C. Department of Electrical Engineering Princeton University Princeton NJ 08544 U.S. Army Research Laboratory Adelphi MD 20783

The versatility of quantum well infrared photodetector (QWIP) structures allows for voltage tunable detection. However, the existing designs generally suffer from limited range of tunability and substantial spectral cross-talk. In this work, we demonstrated a QWIP structure, which is capable of detecting four widely separated and narrowly peaked individual bands under different bias. The detection peaks range from mid-wavelength to long-wavelength and are centered at 4.5, 5.3, 8.3, and 10.4 μm, respectively, with Δλ/λ < 0.14. With f/1.2 optics, the detector is BLIP at 100K, 80K, 60K and 50K respectively for the increasing wavelengths. This four-color detector consists of two stacks of voltage tunable materials that are separated by a middle contact layer. Each material is designed to detect at two specific wavelengths depending on the bias polarity. In the present design, the upper stack switches between 5.3 μm and 10.4 μm, while the bottom stack switches between 4.5 μm and 8.3 μm. By applying different bias to the top and bottom contacts relative to the common middle contact, the optical signal for each color can be readout at the two contacts sequentially. The tunable material is made of repeated unit cells, and each unit cell contains two different superlattices separated by a thick barrier. Based on this design, the detection peaks can be randomly selected between 3 μm and 20 μm, and each peak can vary from narrow band to broadband. The present detector design thus improves the QWIP technology in multi-color detection.

关键词： Semiconductor quantum wells

来源：评论

学校读者我要写书评

暂无评论

A new multi-spectral detector of crop growth condition based on fiber optics

A new multi-spectral detector of crop growth condition based...

引用

infrared and photoelectronic imagers and detector devices

作者： Zhang, Xijie Li, Minzan Zhang, Yane Key Laboratory of Modern Precision Agriculture System Integration Research China Agricultural University Ministry of Education Beijing 100083 China

A multi-spectral detector was developed to evaluate crop growth condition. The detector mainly consists of three parts, a fiber, two sensors, and a MCU. Since two wavelengths were usually used to form an index to evaluate crop growth condition, the fiber was designed to be in "Y" type in order to measure crop reflectance at two different wavelengths. The fiber collect reflect light in one side from crop leaf or canopy and the collected light was divided into two parts and introduced to two sensors. The sensor is composed of a light guiding pipe, an inlet, two gaskets, an interferential filter, a photoelectric cell, and others. It can form a closed space in the center in order to measure reflecting light without external noise. Two different filters were used in two sensors with different special transmission wavelengths so that the reflect lights at wanted wavelengths could be obtained. The MCU was used to amplify signal, display measurement, and record data. It can calculate an evaluation index of crop growth condition from measured reflectance by an embedded evaluation model. It can also transmit data to PC or other storage device. Performance test was conducted. The wavelengths of two interferential filters were selected as 527 nm and 762 nm based on the result of field test. The result shows that the detector can measure the spectral reflectance of crop leaf in high sensitivity and accuracy. And the Normalized Difference Color Index calculated from the reflectance can be used to evaluate crop growth condition well.

关键词： Fiber optics

来源：评论

学校读者我要写书评

暂无评论

Perspectives on dualband infrared focal plane array efforts

Perspectives on dualband infrared focal plane array efforts

引用

conference on infrared Systems and photoelectronic Technology

作者： LeVan, PD USAF Res Lab AFRL VSSS Kirtland AFB NM 87117 USA

ISBN: (纸本)0819455016

Over the years there has been considerable investments in dualband infrared focal plane array (FPA) technology. Both quantum well photodetector and HgCdTe photovoltaic approaches have now achieved dualband-imaging capability. The fruits of these investments are being realized with FPAs that approach levels of performance and maturity sufficiently high to meet end-user needs. Dualband FPAs were developed primarily in support of conceptual surveillance, acquisition and tracking scenarios for a variety of target types. These dualband FPAs may be considered the functional equivalent of dual-channel imagers comprising a dichroic beamsplitter and two distinct FPAs. The volume and cooling requirements of the dual-channel imagers are appreciable relative to the single, dualband FPA. Novel spectral imaging concepts are also enabled with the current dual band, and future multi-waveband, FPA technologies.

关键词： infrared detector focal plane array dualband imaging

来源：评论

学校读者我要写书评

暂无评论

Data collection with a dual-band infrared hyperspectral imager

Data collection with a dual-band Infrared hyperspectral imag...

引用

infrared and photoelectronic imagers and detector devices

作者： Smith, Dale J. Gupta, Neelam U.S. Army Research Laboratory 2800 Powder Mill Road Adelphi MD 20783 United States

A novel dual-band hyperspectral imaging system has been used to collect field test data for robotics vision applications. The imaging system can collect full scene hyperspectral images in both the long-wave infrared (LWIR) band (8-10.5 μm) and the mid-wave infrared (MWIR) band (4-5.25 μm) simultaneously. The imager uses a specially designed Ge diffractive lens with a dual-band 320×240 HgCdTe infrared focal plane array (FPA) cooled with a Sterling cooler. The stacked FPA consists of two layers: the top one sensitive in the MWIR region and the bottom one sensitive in the LWIR region. The diffractive lens is designed to focus a first order, single-color (i.e., 8.0 μm) image in the LWIR onto the bottom layer of the FPA while at the same time focusing a second order single-color (i.e., 4.0 μm) image in the MWIR onto the top layer of the FPA. Images at different wavelengths are acquired by moving the lens along its optical axis. Moving the lens over the entire range during data collection allows sequential collection of spectral images in each band resulting in the collection of two complete image cubes. The focal length of the lens is 75 mm at 9 μm. The spectral resolution of the imager is 0.1 μm at the 9 μm wavelength. In general, 128 narrow wavelength bands are collected in each of the two broad spectral regions. After data collection, the images are processed to remove noise, contributions from unfocused wavelengths, and magnification differences. A description of the imager, data collection, noise removal, post-processing, and analysis are presented.

关键词： Image sensors

来源：评论

学校读者我要写书评

暂无评论

Optical properties of quantum dot infrared photodetector with dot in an asymmetric well structure

Optical properties of quantum dot infrared photodetector wit...

引用

infrared and photoelectronic imagers and detector devices

作者： Lim, J.Y. Shin, J.C. Song, J.D. Choi, W.J. Lee, J.I. Yang, H.S. Choe, J.W. Nano Device Research Center KIST P.O.Box 131 Cheongryan Seoul 130-650 Korea Republic of Thin-Film Semiconductor Lab. Dept. of Physics Chung-Ang Univ. Seoul 156-756 Korea Republic of Semiconductor Device Lab. Dept. of Physics Kyunghee Univ. SuWon 449-701 Korea Republic of

We have investigated the device characteristics of quantum dot infrared phto detector (QDIP) utilizing InAs QDs in an In0.15Ga 0.85As quantum well structure. Device characteristics, such as dark current, photoluminescence (PL), and photocurrent spectra, have been measured. Two peak positions were measured at 163 and 219 meV in photocurrent spectrum. The photo-current of the peak at 163 meV was larger than that at 219 meV. The full width at half maximum (FWHM) of the peak at 163 meV was 18 meV, which was attributed to bound-to-bound transition. In0.15Ga0.85As layers were believed to contribute to induce bound-to-bound transition energy (163 meV). The activation energies of electrons in an InGaAs QDs were determined to be 171 meV and 221 meV from temperature-dependent integrated PL intensities. These activation energies from PL measurement are quite well matched to peak IR detection energies of 163 meV and 219 meV from the photo-current spectrum. This result implies that one can estimate the peak IR detection wavelength of QDIP from PL measurements of QDIP structure before its fabrication and measurement.

关键词： Semiconductor quantum dots

来源：评论

学校读者我要写书评

暂无评论

The development and application of single-photon detectors

The development and application of single-photon detectors

引用

conference on infrared Systems and photoelectronic Technology III

作者： Zhang, Xuejiao Wan, Junli Yan, Chaojun Dong, Fangmin China Three Gorges Univ. (China)

ISBN: (纸本)9780819472755

The development and application of single-photon detectors are introduced. The operating principles of photomultiplier tube (PMT), avalanche photodiode (APD) and superconducting, single-photon detector (SSPD) are expounded. The characteristic, advantages and disadvantages of them are discussed. Then give a view for the perspective and the development of these devices. In the above types of single-photon detectors, the PMT can't detect photon in near-infrared while the APD has great advantage on it, so it is the most preponderant detector in the single-photon detection. The capability of SSPD are excelled the former single-photon detectors, besides, it can detect the arriving time and energy of the photon, so it has great potential in the astronomical observation and the high-speed quantum communication and so on.

关键词： Single-photon detector PMT APD SSPD

来源：评论

学校读者我要写书评

暂无评论

Pyroelectric sensor arrays for detection and thermal imaging

Pyroelectric sensor arrays for detection and thermal imaging

引用

conference on infrared Technology and Applications XXXIX

作者： Holden, Anthony J. InfraRed Integrated Syst Ltd Pk Circle Northampton NN49BG England

ISBN: (纸本)9780819494955

Penetration of uncooled (room temperature operation) thermal detector arrays into high volume commercial products depends on very low cost technology linked to high volume production. A series of innovative and revolutionary developments is now allowing arrays based on bulk pyroelectric ceramic material to enter the consumer marketplace providing everything from sophisticated security and people monitoring devices to hand held thermal imagers and visual IR thermometers for preventative maintenance and building inspection. Although uncooled resistive microbolometer detector technology has captured market share in higher cost thermal imager products we describe a pyroelectric ceramic technology which does not need micro electro-mechanical systems (MEMS) technology and vacuum packaging to give good performance. This is a breakthrough for very low cost sensors and imagers. Recent developments in a variety of products based on pyroelectric ceramic arrays are described and their performance and applicability compared and contrasted with competing technologies.

关键词： Pyroelectric Arrays Pyroelectric Ceramic Thermal imagers Thermal detectors People Counters infrared detector arrays Visual Thermometer

来源：评论

学校读者我要写书评

暂无评论

Uncooled long wavelength infrared photon detectors

Uncooled long wavelength infrared photon detectors

引用

conference on Quantum Sensing and Nanophotonic devices

作者： Piotrowski, J Rogalski, A Vigo Syst Ltd PL-01397 Warsaw Poland

ISBN: (纸本)081945267X

At present, uncooled thermal detector focal plane arrays are successfully used in staring thermal imagers. However, the performance of thermal detectors is modest, they suffer from slow response and they are not very useful in applications requiring multispectral detection. In the paper, a number of concepts to improve performance of photon detectors operating at room temperature are presented. Several types of detector materials are considered: HgCdTe, Sb-based III-V ternary alloys, and type-II InAs/GaSb superlattice. Initial efforts were concentrated on photoconductors and photoelectromagnetic detectors. Recently, advanced heterojunction photovoltaic detectors have been developed. It is shown that uncooled HgCdTe photovoltaic detector can achieve detectivity of 10(9) cmHz(1/2)W(-1) at the 8-9 mum range. Potentially the devices can be assembled in large focal plane arrays. This will enable obtaining of NEDT of less than 0.1 K for staring thermal imagers operating with f/1 optics and 30 s(-1) frame rate.

关键词： Sensors Photodetectors Thermography Mercury cadmium telluride Long wavelength infrared Resistance Photodiodes infrared sensors Photoresistors Semiconductors

来源：评论

学校读者我要写书评

暂无评论

3D simulation of detector parameters for backside illuminated InSb 2-D arrays

3D simulation of detector parameters for backside illuminate...

引用

conference on infrared Systems and photoelectronic Technology II

作者： Fishman, Tal Nahum, Vered Saguy, Erez Calahorra, Zippora Shtrichman, Itay SemiConductor Devices SCD IL-31021 Haifa Israel

ISBN: (纸本)9780819468086

Accurate and reliable numerical simulation tools are necessary for the development of advanced semiconductor devices. SCD is using the Silvaco Atlas simulation tool to simultaneously solve the Poisson, Continuity and transport equations for 3D detector structures. In this work we describe a set of systematic experiments performed in order to calibrate the Atlas simulation to SCD's backside illuminated InSb focal plane arrays (FPA) realized with planar technology. From these experiments we extract physical parameters such as diffusion length, surface recombination velocity, and SRH lifetime. The actual and predicted performance (e.g. dark-current and MTF) of present and future detectors is presented. We have studied arrays with pitch in the range of 15 to 30 mu m. We find that the MTF width is inversely proportional to the pitch. Thus, the spatial resolution of the detector improves with decreasing pixel size as expected. Using the Atlas simulation we predict the performance of planar InSb arrays with smaller pixel dimensions, e.g., 12 and 10 mu m.

关键词： infrared detector InSbFPA MTF device simulation

来源：评论

学校读者我要写书评

暂无评论

InAs/GaSb superlattice infrared detectors

引用

infrared PHYSICS & TECHNOLOGY 2013年 59卷 6-11页

作者： Rehm, Robert Masur, Michael Schmitz, Johannes Daumer, Volker Niemasz, Jasmin Vandervelde, Thomas DeMeo, Dante Luppold, Wolfgang Wauro, Matthias Woerl, Andreas Rutz, Frank Scheibner, Ralf Ziegler, Johann Walther, Martin Fraunhofer Inst Angew Festkorperphys IAF D-79108 Freiburg Germany AIM Infrarot Module GmbH D-74072 Heilbronn Germany Tufts Univ Dept Elect & Comp Engn Renewable Energy & Appl Photon Labs Medford MA 02155 USA

Future heterojunction InAs/GaSb superlattice (SL) detector devices in the long-wavelength infrared regime (LWIR, 8-12 mu m) require an accurate bandstructure model and a successful surface passivation. In this study, we have validated the superlattice empirical pseudopotential method developed by Dente and Tilton over a wide range of bandgap energies. Furthermore, dark current data for a novel dielectric surface passivation for LWIR devices is presented. Next, we present a technique for high-resolution, full-wafer mapping of etch pit densities on commercial (100) GaSb substrates, which allows to study the local correlation between threading dislocations in the substrate and the electro-optical pixel performance. Finally, recent performance data for 384 x 288 dual-color InAs/GaSb superlattice imagers for the mid-wavelength infrared (MWR, 3-5 mu m) is given. (c) 2013 Elsevier B.V. All rights reserved.

关键词： InAs/GaSb superlattice infrared focal plane array Dual-color MWIR LWIR Superlattice empirical pseudopotential method

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：