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作者： Wang, Rongyang Yuan, Yonggang Li, Chao Zhang, Yan Li, Xiangyang State Key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China Key Laboratory of Infrared Imaging Materials and Detectors Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China

Three LED-based signal transmitting schemes were presented to build the transmitter of UV communication system. Microprogrammed Control Unit (MCU) was taken to generate digital driving signal and to accomplish modulation with Keil C51 development tool. The modulated signal with a certain pulse width was sent to a LED driving circuit. High power 365nm UV LED was adopted according to the trade-off between its scattering coefficient and price. Utilization of high power UV LED improved the integration density of printed circuit board (PCB), which was beneficial to assemble a beam shaping system. The whole transmitter was installed on a four-dimensional optical stage for system adjustments and measurements. The radiant optical power of UV LED was measured. Some issues about the PCB design were also discussed. The MCU output waveforms were demonstrated on an oscilloscope and the UV LED output optical pulse were verified by a Hamamatsu APD module. Different modulation data rates were investigated. Experimental result showed that this signal transmitter for UV communication system could transmit optical signal well and greatly shorten the system development cycle.

关键词： Modulation

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AlGaN-based material characterizations and recent development of related solar-blind ultraviolet detectors

AlGaN-based material characterizations and recent developmen...

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Photonics and Optoelectronics Meetings (POEM) 2009 - Solar Cells, Solid State Lighting, and Information Display Technologies

作者： Li, Xiangyang Xu, Jintong Zhang, Yan Yuan, Yonggang Chu, Kaihui Li, Chao Bao, Xichang Wang, Ling Key Laboratory of Infrared Imaging Materials and Detectors Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China State Key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China

ISBN: (纸本)9780819479075

Recently, AlGaN-based material and related devices have been investigated intensively because of their applications in ultraviolet solar-blind detectors, blue light-emitting diodes, UV laser diodes, and high-power-temperature devices. Due to intrinsic difficulty to grow high aluminum fraction material, achieving reasonable good quality of wafers is the key aspect to fabricate high performance solar-blind AlGaN-based detectors. Transmission spectra, XRD, and a two dimension transmission scanning system were employed to evaluate the properties of AlGaN-based material. Wet chemical etching process of n-type AlGaN in 20% aqueous KOH solutions was performed to reduce dry etching damages and the average leakage current. I-V characterization indicated that the average leakage current of the wet etching treated detectors was lower than that of the detectors without treatment by about one order of magnitude. Ti/Al/Ti/Au contact on n-type Al0.63Ga0.37N was optimized to get a low series resistance. 128128 solar-blind AlGaN UV Focal Plane Arrays (FPAs) were fabricated and the performance were characterized. A CTIA (capacitive-transimpedance) readout circuit architecture has been proven to be well suited for AlGaN detectors arrays. The results show that 128128 back-illuminated AlGaN PIN detector SNR is as high as 74 db at a speed of above 30 frames per second. © 2009 Copyright SPIE - The International Society for Optical Engineering.

关键词： Aluminum gallium nitride

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[POSTER] ORBFusion: Real-Time and Accurate Dense SLAM at Large Scale

[POSTER] ORBFusion: Real-Time and Accurate Dense SLAM at Lar...

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IEEE International Symposium on Mixed and Augmented Reality Workshops (ISMARW)

作者： Juting Dai Xinyi Tang Leif Oppermann Key Laboratory of Infrared System Detection and Imaging Technology Fraunhofer Institute for Applied Information Technology FIT University of Chinese Academy of Sciences Shanghai Institute of Technical Physics of The Chinese Academy of Sciences

ISBN: (纸本)9781538614549

We present a new SLAM system capable of producing high quality globally consistent surface reconstructions with accurate real-time tracking and localization abilities. The system works on an off the shelf laptop with a typical GPU. This paper proposes an approach to unify feature-based keyframe techniques with fused volumetric surface reconstruction methods to overcome both of their limitations. On one hand, feature-based keyframe SLAM techniques have reached a level of maturity and can guarantee accurate and real-time tracking and localization ability, but their raw RGB-D point clouds are too noisy. On the other hand, volumetric surface reconstruction methods can produce a dense surface reconstruction of the environment, which will be helpful for Augmented Reality (AR) applications and scene understanding. However, current dense SLAM systems have limited tracking ability, which is vital for the quality of surface reconstruction. Moreover most of the current dense SLAM systems have to run on a powerful desktop PC to guarantee realtime performance. By unifying the feature-based keyframe tracking ability and adopting a multi-threaded design, our system improves both the tracking ability and the real-time performance. We present results of a wide variety of aspects of our system and evaluate it using the widely used TUM RGB-D and ICL-NUIM Datasets. Our system achieves unprecedented performance in terms of trajectory estimation, surface reconstruction, real-time and computational performance in comparison to other start-of-the-art dense RGB-D SLAM systems.

关键词： Augmented reality

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A 320×256 readout circuit with wide dynamic range and high injection efficiency 5

A 320×256 readout circuit with wide dynamic range and high ...

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5th Symposium on Novel Optoelectronic detection technology and Application

作者： Ma, Ding Li, Xiang-Yang Zhang, Yan Liu, Fu-Hao State Key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai200083 China Key Laboratory of Infrared Imaging Materials and Detectors Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai200083 China

ISBN: (数字)9781510627130

ISBN: (纸本)9781510627123

A 320×256 readout integrated circuit (ROIC) with a pixel pitch of 30μm is presented for solar-blind AlGaN ultraviolet focal array plane (FPA). Capacitor feedback transimpendance amplifier (CTIA) has been selected as the input structure of the ROIC because of its excellent performance. A novel cascade amplifier with a symmetrical differential input stage is designed for input stage of CTIA, and an ultra-low capacitance with a value of 10fF is in the feedback loop of the amplifier as integral capacitor. Furthermore, the ROIC read out in a rolling shutter mode by using cascade D flip-flops. The ROIC has been fabricated 0.35μm 2P4M mixed signal CMOS process and interfaced with AlGaN solar-blind ultraviolet focal array plane (UVFPA). The test result shows that 320×256 AlGaN UVFPA has a wide dynamic range of 88.2dB with 5V power supply and has a high injection efficiency of 98.2%. © 2019 SPIE.

关键词： Timing circuits

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Response prediction for mechanical systems subject to combinationalstructural modifications

Response prediction for mechanical systems subject to combin...

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第八届国际振动工程会议

作者： Zengwei Wang Lei Ding Zhike Peng Xi Shi Key Laboratory of Infrared System Detection and Imaging Technology Chinese Academy of Sciences Shanghai Institute of Technical Physics Chinese Academy of Sciences State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

A method is proposed for predicting the dynamic response of mechanical systems subject to combinational structural modifications. It can be found that dynamic responses of mechanical systems subject to combinational structural modifications can be calculated from the variant transmissibility matrices of the one-modification system and the dynamic response of the base system, even though operational forces are unknown. The variant transmissibility is defined to relate the response of the modified system and that of the base system. The dynamic coupling between structural modifications to the system is also investigated. The achievements can be used to reduce the computational cost of determining the optimal combination of design *** benefits of the proposed method are illustrated and validated using the numerical example,finite element simulations and experimental case studies.

关键词： Response prediction for mechanical systems subject to combinationalstructural modifications

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Wet chemical etching of Al0.65Ga0.35N in aqueous KOH solutions

Wet chemical etching of Al0.65Ga0.35N in aqueous KOH solutio...

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Photonics and Optoelectronics Meetings (POEM) 2009 - Solar Cells, Solid State Lighting, and Information Display Technologies

作者： Xu, Jintong Chen, Jie Su, Zhiguo Zhang, Yan Li, Xiangyang Key Laboratory of Infrared Imaging Materials and Detectors Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China State Key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China

ISBN: (纸本)9780819479075

We have investigated wet chemical etching of Al0.65Ga0.35N in 20% (by weight) aqueous KOH solutions at 85, 95 and 102 °C. The etch rates were 0.48, 0.64 and 0.96 μm/min, respectively. Scanning electron microscope, atomic force microscopy, Auger electron spectroscopy and x-ray photoelectron spectroscopy were employed to characterize the surface morphology and stoichiometry before and after wet chemical etching. Experimental results show that aqueous KOH solutions can effectively etch Al0.65Ga 0.35N. SEM results show that the root-mean-square (rms) roughness increased from 16.189 to 50.496 nm. Degradation in surface smoothness is attributed to selective anisotropic wet chemical etching. The AES measurements show that after the untreated sample was wet chemical treated in a 20% KOH solution at 85 °C for 15 seconds, the oxide formed in the surface was removed and a lower content of oxide layer near the surface was formed and the N content is higher. XPS measurements show that the banding energies of Ga 3d shifted to low energy direction after the untreated sample was successively wet chemical treated. It indicated that the atom Ga tended to form Ga-N rather than Ga-O bonding on the surface after KOH solution treatment. The damage and oxide layer induced by dry etching processes was effectively removed by wet chemical treatment and the damage surface was refreshed. © 2009 Copyright SPIE - The International Society for Optical Engineering.

关键词： X ray photoelectron spectroscopy

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Fabrication of Tb/Eu co-doped borosilicate glasses for white-light LED and broadband photodetection

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Journal of Rare Earths 2025年

作者： Jia, Hong Wang, Yingying Long, Yi Niu, Xuying Zhou, Hui Yang, Jie Yuan, Yuquan Hu, Yanfei Xu, Xiaoyun Liu, Xiaofeng Peng, Feng Fang, Zaijin College of Physics and Electronic Information & Key Laboratory of Electromagnetic Transformation and Detection of Henan Province Luoyang Normal University Luoyang 471934 China Henan Academy of Sciences Institute of Applied Physics Co. Ltd. Zhengzhou 450000 China Research Center for Novel Solar-Blind Ultraviolet and Infrared Photoelectronic Detectors & Longmen Laboratory of Luoyang Luoyang 471000 China School of Physics and Electronic Engineering Sichuan University of Science & Engineering Zigong 643000 China Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Institute of Photonics Technology Jinan University Guangzhou 511443 China Department of Applied Physics College of Mathematics and Physics Chengdu University of Technology Chengdu 610059 China Guangzhou City University of Technology Guangzhou 510800 China School of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

We successfully prepared a series of rare-earth doped borosilicate glasses using the melt-quenching method, and carefully investigated the luminescent properties and the spectral modulation of Tb/Eu-codoped borosilicate glasses under UV (200–400 nm) excitation. The results show that the prepared samples have the characteristics of broadband response, excellent transparency and tunable luminescence. By adjusting the excitation wavelength, the emissions of Tb³⁺, Eu²⁺ and Eu³⁺ ions are observed, which exhibit yellow-green, blue, red color and multi-color even white emissions, respectively. Moreover, the energy transfer between Tb³⁺ and Eu³⁺ ions in the codoped glasses is confirmed. Tb³⁺ absorbs a large number of solar-blind light, transfers to Eu³⁺ and results in intense visible emission in a wide waveband range. This makes the Tb/Eu co-doped glass a desirable candidate for solar-blind light detections. The photodetection system was built and shows a strong and stable response to the UV light of 210–400 nm. Due to broad detection range, high sensitivity and stability, our results offer strong implications for the development of photodetection device for diverse applications. © 2025

关键词： Borosilicate glass Photodetectors Rare earth ions Tb/Eu co-doped

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Superposed probabilistically shaped QAM constellation design based on nonlinear coding for MIMO visible light communication systems

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Chinese Optics Letters 2024年第6期22卷 109-115页

作者： Xinyue Guo Meixia Lu Qibin Zheng Key Laboratory of Optical Technology and Instrument for Medicine Ministry of EducationSchool of Optical-Electrical and Computing EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China Laboratory of Radiation Detection and Medical Imaging School of Health Science and EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

In this study, we propose a superposed probabilistically shaped(PS) quadrature amplitude modulation(QAM) constellation scheme for multiple-input multiple-output visible light communication systems. PS QAM signals are generated from a nonlinear coding equation that converts uniformly distributed 8-level signals into PS 9-or 10-level signals, which are then mapped into PS 9QAM or 10QAM signals. Square-shaped 9QAM and trapezoid-shaped 10QAM constellations are introduced to maximize the minimum Euclidean distance(MED) of the superposed constellation. Finally, the PS 9QAM and 10QAM signals are superposed with the 4QAM signals in a flipped manner to obtain PS 36QAM or 40QAM signals at the receiver, *** exploit the temporal correlation of the resulting signal from nonlinear coding, we developed a detection algorithm based on Viterbi decoding. Experimental results confirmed the superiority of the proposed schemes by achieving a higher MED and stronger ability to resist nonlinearity. Compared with the traditional scheme, the peak-to-peak voltage dynamic ranges of the superposed 36QAM and 40QAM constellation schemes were improved by 52% and 48%, respectively.

关键词： visible light communication superposed constellation nonlinear coding

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Adversarial Examples Generation Through Attacking the 1 × 1 Convolution Operator

Adversarial Examples Generation Through Attacking the 1 × 1...

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2022 International Conference on Blockchain technology and Information Security, ICBCTIS 2022

作者： Wang, Yang Cao, Tieyong Yang, Jibin Zheng, Yunfei Fang, Zheng Yang, Zhen Institute of Command-and-Control Engineering Army Engineering University of Pla Jiangsu Nanjing China The Army Artillery and Defense Academy of Pla Jiangsu Nanjing China The Key Laboratory of Polarization Imaging Detection Technology Anhui Hefei China

ISBN: (数字)9781665496919

ISBN: (纸本)9781665496919

Convolution neural networks (CNN) are vulnerable to adversarial attack, which brings security risks to the application of convolutional neural networks in reality. Adversarial attacks are usually done by adding subtle perturbations in images to fool models to output wrong results. In black-box conditions, the transferability of attack method is mostly focused to fool more model. To enhance the transferability of adversarial attack, we proposed an attack method against the commonly used 1× 1 convolution operator (1ConvA, 1× 1 Convolution Attack), which exists in many convolutional networks for improving the complexity of the model and the gradient flow. Experiments on many CNNs demonstrate 1ConvA can generate adversarial examples with better transferability. © 2022 IEEE.

关键词： Convolution

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Model and Analysis of the top of Atmosphere’s Polarization Radiation Characteristics based on Ocean Scene 3

Model and Analysis of the top of Atmosphere’s Polarization ...

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3rd International Computing imaging Conference, CITA 2023

作者： Wu, Lingxia Zeng, Xianfang Wu, Yunzhi Huang, Qinchao Huang, Qiheng Army Academy of Artillery and Air Defense of PLA Hefei Anhui230031 China Anhui Provincial Key Laboratory of Polarization Imaging Detection Technology Hefei Anhui230031 China Anhui Water Conservancy Technical College China

ISBN: (纸本)9781510671409

In view of the problem of attenuation or polarization state change caused by atmospheric radiation transmission in the long-distance path transmission of target polarization information, the atmospheric polarization characteristics based on atmospheric vector radiative transmission are studied, and the polarization characteristic modeling is completed. First using rough sea surface Cox-Munk model and Fresnel reflection law to simulate the real sea surface radiation state, determine the environmental data needed for the simulation, then based on radiation transmission simulation tools analysis of atmospheric Rayleigh scattering and aerosol scattering influence on the polarization radiation state, finally with the sea surface radiation state coupling get atmospheric top polarization radiation state. In order to verify the correctness of the proposed modeling method, the modeling results of this method are compared with the data actually obtained by the polarization detector of DPC. The results show that the overall trend and consistency of the observed and simulated values are good. This method can effectively simulate the polarization characteristics of the sea atmosphere in sunny and cloudy weather, and provide good data support for the offshore polarization detection in sunny and cloudy weather conditions. © 2023 SPIE.

关键词： Surface waters

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