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conference on Technologies for Optical Countermeasures VII

作者： Bigotta, Stefano Eichhorn, Marc Inst Franco Allemand Rech St Louis ISL F-68301 St Louis France

ISBN: (纸本)9780819483546

Er(3+):YAG eye-safe laser emitting at 1.6 mu m is an interesting source for various applications such as remote sensing, ranging, designation and free-space communications for two main reasons: its emitting wavelength lies in a region of high atmospheric transmission and high sensor sensitivity and the resonant pumping into the (4)I(13/2) upper laser manifold ensures highly efficient operation. The recent availability of internal grating stabilized narrow linewidth, high-power laser diodes in the 1.53 mu m range, makes this laser even more appealing. The only shortcoming to be solved for a really efficient resonantly diode pumped Er(3+):YAG laser is how to have a good overlap between the pump radiation and the laser cavity mode. Indeed, due to up-conversion processes among the Er(3+) ions, to achieve efficient lasers it is necessary to use low doped samples. This requires the use of rods with lengths of several cm that are not compatible with the low beam quality of the diode lasers. In this work, we report on a resonantly diode pumped Q-switched Er(3+):YAG laser with a crystalline fibre-like geometry emitting at 1.64 mu m. In this scheme, the pump radiation is confined into a 60 mm long crystal with a diameter of 1.2 mm thanks to the multiple total internal reflections (TIR) that occur on the barrel surface, allowing efficiently pumping of such a long crystal. A maximum output power of more than 14 W in continuous wave mode and pulse energies of 8 mJ in Q-switching mode have been observed, when pumped with similar to 40 W of absorbed power. Even if these values are still far from the performances reported using hybrid fibre-bulk laser scheme, these results clearly show that TIR-based Er(3+):YAG fibre-shaped crystalline rod laser is a promising technology for the development of efficient high-power and high-energy eye-safe laser. Finally, the effect of thermal lensing on such crystalline fibre geometry is discussed.

关键词： lasers diode-pumped lasers erbium lasers solid-state

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THE MODELLING OF A CAPACITIVE MICROsensor FOR BIOSENSING applications

THE MODELLING OF A CAPACITIVE MICROSENSOR FOR BIOSENSING APP...

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3rd South African conference on sensors, MEMS, and Electro-Optical Systems (SMEOS)

作者： Bezuidenhout, P. H. Schoeman, J. Joubert, T. H. Univ Pretoria Dept Elect Engn & Comp Engn ZA-0002 Pretoria South Africa CSIR Mat Sci & Mfg Pretoria South Africa

ISBN: (纸本)9781628413243

Microsensing is a leading field in technology due to its wide application potential, not only in bio-engineering, but in other fields as well. Microsensors have potentially low-cost manufacturing processes, while a single device type can have various uses, and this consequently helps with the ever-growing need to provide better health conditions in rural parts of the world. Capacitive biosensors detect a change in permittivity (or dielectric constant) of a biological material, usually within a parallel plate capacitor structure which is often implemented with integrated electrodes of an inert metal such as gold or platinum on a microfluidic substrate typically with high dielectric constant. There exist parasitic capacitance components in these capacitive sensors, which have large influence on the capacitive measurement. Therefore, they should be considered for the development of sensitive and accurate sensing devices. An analytical model of a capacitive sensor device is discussed, which accounts for these parasitic factors. The model is validated with a laboratory device of fixed geometry, consisting of two parallel gold electrodes on an alumina (Al2O3) substrate mounted on a glass microscope slide, and with a windowed cover layer of poly-dimethyl-siloxane (PDMS). The thickness of the gold layer is 1 mu m and the electrode spacing is 300 mu m. The alumina substrate has a thickness of 200 mu m, and the high relative permittivity of 11.5 is expected to be a significantly contributing factor to the total device capacitance. The 155 mu m thick PDMS layer is also expected to contribute substantially to the total device capacitance since the relative permittivity for PDMS is 2.7. The wideband impedance analyser evaluation of the laboratory device gives a measurement result of 2pF, which coincides with the model results;while the handheld RLC meter readout of 4pF at a frequency of 10kHz is acceptable within the measurement accuracy of the instrument. This validated model w

关键词： capacitive biosensor parasitic capacitances capacitive microsensor microsensor

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A unifying interface abstraction for accelerated computing in sensor nodes

A unifying interface abstraction for accelerated computing i...

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Electronic System Level Synthesis conference (ESLsyn)

作者： Srikrishna Iyer Jingyao Zhang Yaling Yang Patrick Schaumont Department of Electrical and Computer Engineering Virginia Polytechnic Institute and State University Blacksburg VA USA

Hardware-software co-design techniques are very suitable to develop the next generation of sensornet applications, which have high computational demands. By making use of a low-power FPGA, the peak computational performance of a sensor node can be improved without significant degradation of the standby power dissipation. In this contribution, we present a methodology and tool to enable hardware/software codesign for sensor node application development. We present the integration of nesC, a sensornet programming language, with GEZEL, an easy-to-use hardware description language. We describe the hardware/software interface at different levels of abstraction: at the level of the design language, at the level of the co-simulator, and in the hardware implementation. We use a layered, uniform approach that is particularly suited to deal with the heterogeneous interfaces typically found on small embedded processors. We illustrate the strengths of our approach by means of a prototype application: the integration of a hardware-accelerated crypto-application in a nesC application.

关键词： Hardware Field programmable gate arrays Program processors Computer architecture Kernel Synchronization

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Small HgCdTe infrared detector arrays from UWA

Small HgCdTe infrared detector arrays from UWA

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conference on Optoelectronic and Microelectronic Materials and Devices

作者： J. Antoszewski C.A. Musca J.M. Dell L. Faraone M. Wagener I. Switala R. Oermann School of Electrical Electronic & Computer Engineering University of Western Australia Crawley WA Australia Defence Science and Technology Organisation Edinburgh SA Australia

Single infrared detectors and small arrays find widespread applications in spectroscopy, radiometry, scanning imaging systems, target tracking etc. The technology of such devices based on mercury cadmium telluride (HgCdTe), the material of choice for high performance infrared detectors, has been a subject of intensive research in many countries. Projects conducted in this field at The University of Western Australia resulted in the development of a technology that allows the fabrication of state of the art photovoltaic infrared detectors with n- on p-junctions obtained by plasma induced type conversion using reactive ion etching (RIE). Using this technology, small arrays have been fabricated, flip chip bonded to readout/fanout, packaged and tested. The arrays comprised of 8 /spl times/ 8 photodiodes with 50 /spl mu/m /spl times/ 50 /spl mu/m size and 100 /spl mu/m pitch, passivated with thermally evaporated CdTe/ZnS double layer. The best arrays are 100% operational and highly uniform. In this paper properties of these detector arrays are presented and analysed.

关键词： Infrared detectors sensor arrays Spectroscopy Radiometry Optical imaging Target tracking Cadmium compounds Conducting materials Fabrication Photovoltaic systems

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Terahertz Imaging with a Quantum Cascade Laser and a Pixelless Imaging Chip

Terahertz Imaging with a Quantum Cascade Laser and a Pixelle...

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IEEE International conference on Plasma Science (ICOPS)

作者： Zhanglong Fu Dixiang Shao Wenjian Wan Zhiyong Tan Zhenzhen Zhang Liangliang Gu Juncheng. Cao Key Laboratory of Terahertz Solid-State Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China

ISBN: (纸本)9781728153087

Terahertz imaging has drawn a widely attention for the potential applications in deep space exploration, material analysis, medical imaging, security screening, and situation awareness in fire disasters nowadays 1–5 . However, lack of large-format (many-pixels) sensor arrays, especially the fast imaging arrays, is one of the major hurdles for the proliferation of THz sensing methodologies and related applications 5 . Therefore, we fabricated a pixel-less photo-type terahertz imager based on the frequency up-conversion technique to realize the real-time and fast THz imaging. The device is composed of a terahertz quantum well photodetector (THz QWP) and a near-infrared light emitting diode (LED) that grown in sequence on the same substrate with molecular beam epitaxy. In such an integrated device (THz QWP-LED), electronics of the THz QWP in the bound state were excited to the continuous state to form photocurrent by absorbing of THz photonics, and it drives the LED to emit near-infrared light. The chip has a peak response of ∼0.5 A/W at 4.8 THz and a noise equivalent power (NEP) of ∼ pW/Hz 0.5 . We setup terahertz imaging systems to base on a quantum cascade laser (QCL) and a THz QWP-LED. The systems has an imaging resolution of ∼ $100\ \mu\ \mathrm{m}$ and a capacity of fast imaging within 10 µs. This device opens a new way to realize high performance real-time and fast terahertz imaging.

关键词： Terahertz wave imaging Light emitting diodes Real-time systems Space exploration sensors Plasmas Security

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Design of Tunnel Construction Monitoring and Surface Subsidence Warning System Based on ARIMA Model

Design of Tunnel Construction Monitoring and Surface Subside...

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Advances in Electrical Engineering and Computer applications( AEECA), 2020 IEEE International conference on

作者： Feng Tang Yi Ren Qing Zhu Jian He Guifu Xia Chongqing Engineering Quality and Safety General Office of Housing and Urban-Rural Development China Chongqing Airport Group Co. Ltd. China China Construction Third Engineering Bureau Group Co. Ltd. Wuhan China

ISBN: (纸本)9798350355260

Aiming at the demand of high precision monitoring in urban tunnel construction, this paper proposes a computer aided monitoring system based on autoregressive comprehensive moving average autoregressive model. The system incorporates advanced sensor arrays and machine learning algorithms to achieve real-time data acquisition, analysis and early warning of settlement changes during tunnel construction. The experimental results show that the maximum settlement value of the system at the monitoring point SZY-ZL4 is -3mm and the minimum settlement value is -13mm, while the maximum settlement value of the monitoring point SZY-ZL2 is 0mm and the minimum settlement value is -3mm, showing a high degree of monitoring accuracy and cost-effectiveness. By using the average autoregressive model in time series analysis and data mining technology, this study can accurately predict the settlement trend in tunnel construction and give early warning in time. The computer aided monitoring system provides a scientific and efficient safety state assessment and early warning strategy for tunnel construction safety.

关键词： Accuracy Costs Deformation Computational modeling Alarm systems Market research Safety Monitoring Surface treatment sensor arrays

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Tactile mapping of palpable abnormalities for breast cancer diagnosis

Tactile mapping of palpable abnormalities for breast cancer ...

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IEEE International conference on Robotics and Automation (ICRA)

作者： Y. Wang C. Nguyen R. Srikanchana Z. Geng M.T. Freedman Department of Electrical Engineering and Computer Science Catholic University of America Washington D.C. DC USA Catholic University of America Washington DC US Genex Technologies Inc. Kensington MD USA Department of Radiology and the Lombardi Cancer Center George town University Washington D.C. DC USA

This paper presents the development of a prototype tactile mapping device (TMD) system comprised mainly of a tactile sensor array probe, a 3D camera and a force/torque sensor, which can provide the means to produce tactile maps of the breast lumps during a breast palpation. Focusing on the key tactile topology features from breast palpation such as spatial location, size and shape of the detected lesion, and the force levels used to demonstrate the palpable abnormalities, these maps can record the results of clinical breast examination with a set of pressure distribution profiles and force sensor measurements due to detected lesion. These maps will serve as an objective documentation of palpable lesions for future comparative examinations. Preliminary results of simulated experiments and limited pre-clinical evaluations of the TMD prototype have pilot-tested our hypothesis and provided solid promising data showing the feasibility of the TMD in real clinical applications.

关键词： Breast cancer sensor arrays Force sensors Lesions Tactile sensors Shape measurement Force measurement Prototypes Probes Cameras

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Charge Transfer Speed Analysis in Pinned Photodiode CMOS Image sensors based on a Pulsed Storage-Gate Method

Charge Transfer Speed Analysis in Pinned Photodiode CMOS Ima...

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European solid state Device Research conference

作者： Alice Pelamatti Vincent Goiffon Aziouz Chabane Pierre Magnan Cédric Virmontois Olivier Saint-Pé Michel Breart de Boisanger Institut Supérieur de 1'Aéronautique et de l'Espace (ISAE) Université de Toulouse Image Sensor Research Team Toulouse 31055 France. Centre National d'Etudes Spatiales (CNES) Toulouse 31400 France Airbus Defence and Space Toulouse 31030 France

ISBN: (纸本)9781467371360

I. INTRODUCTION DRIVEN by low noise applications, Pinned Photodiode (PPD) [1]-[3] CMOS Image sensors (CIS) have recently become the main image sensors technology for both commercial and scientific applications. The PPD (schematized in Fig. la) consists in a buried photodiode, where the surface p+ implant, also referred to as pinning-implant, pins the surface at the substrate potential. This peculiar structure not only reduces the dark current (by isolating the PPD from the charges generated at the SiO_2-Si interface), but also limits the maximum PPD potential, often referred to as pinning voltage [4], which corresponds to the full depletion condition. The presence of this "potential floor" enables true charge transfer from the PPD to the collection node (or to another buried channel), whereas in standard photodiodes only charge sharing between two capacitances is possible. The combination of these unique features has led in the last decade to the development of several PPD-based detectors for high speed applications, such as Time of Flight (ToF) applications [5]-[8], which require high speed readout of small packets of photocharges. One of the main challenges involved in PPD-based high speed detectors is to reach the best temporal resolution by maximizing the charge transfer speed from the photogeneration site to the collection node. The transfer speed becomes even more critical for applications, such as space imaging applications, which require pixel pitches of several tens of μm (for example for optics-related constraints [9]).

关键词： CIS reach best temporal

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development of X-ray/gamma-ray imaging spectrometers using reach-through APD arrays

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JOURNAL OF INSTRUMENTATION 2012年第3期7卷 C03038-C03038页

作者： Nakamori, T. Enomoto, T. Toizumi, T. Tokoyoda, K. Yatsu, Y. Kawai, N. Kataoka, J. Ishikawa, Y. Kawai, T. Kawabata, N. Matsunaga, Y. Waseda Univ Res Inst Sci & Engn Shinjuku Ku Tokyo Japan Tokyo Inst Technol Fac Sci & Engn Meguro Ku Tokyo 152 Japan Hamamatsu Photon KK Solid State Div Hamamatsu Shizuoka Japan

We present spectroscopic capability of a position sensitive detector using a large area reach-through avalanche photodiode (APD) array, mainly for astronomical applications. It is quite important to obtain wide band spectra of high energy astrophysical phenomena simultaneously in order to probe emission processes or structures. Especially observations of transient objects, such as gamma-ray bursts of active galactic nuclei, require detectors with wide energy band coverage for the sake of an efficient spectroscopy within limited time windows. An APD is a compact semiconductor photon sensor with an internal gain which is often up to similar to 100. A reach-through type APD has a thicker depletion layer thus higher efficiency for direct X-ray detection compared to a reverse type APD. We have developed 1-dimensional reach-through APD arrays which consist of 8 and 16 segments with a pixel size of 2.2x16 and 1.1x16 mm(2). We demonstrated quite uniform gain and energy resolution for 5.9 keV X-ray over the pixels of these arrays. Subsequently we constructed X-ray/gamma-ray detector using the APD array optically coupled to a conventional CsI(T1) scintillator which demonstrated energy coverage typically from 1 keV to 1 MeV.

关键词： Imaging spectroscopy X-ray detectors and telescopes Gamma detectors

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Bottom-up fabrication approaches to large area novel plasmonic materials

Bottom-up fabrication approaches to large area novel plasmon...

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中国光学学会2010年光学大会

作者：王振林 Department of Physics and National Laboratory of Solid State Microstructures Nanjing University

Recent research effort towards fabricating novel metal nanoparticles （NPs） and their ordered arrays have been motivated by the emergence of *** particular,tuning the size,morphology,composition,and the separation of metal NPs has allowed us to engineer both individual nanoparticles and collective properties of plasmonic crystals for specific *** we present our recent development of bottom-up growth methods and demonstrate convenience for the preparation of such plasmonic *** implementation of physical,chemical,or electrochemical deposition of a metal in combination with micromolding on two-dimensional colloidal crystals,ordered metallic NPs with a variety of morphologies can be created with a nanometer spatial tuning *** prepared novel plasmonic crystals could find applications in optics,optoelectronics,materials science,sensing and biophysics.

关键词： Surface plasmons plasmonic crystal colloidal crystal light transmission resonance plasmonic sensor

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