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	Double Domain Guided Real-Time Low-Light Image Enhancement for Ultra-High-Definition Transportation Surveillance 期刊论文 OAI收割 IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS, 2024, 页码: 13 作者: Qu, Jingxiang; Liu, Ryan Wen; Gao, Yuan; Guo, Yu; Zhu, Fenghua \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2024/07/03 Intelligent transportation system (ITS) transportation surveillance low-light image enhancement ultra-high-definition (UHD) double domain guidance
	A real-time ultra-low light color imaging system based on FPGA 会议论文 OAI收割 Kuala Lumpur, Virtual, Malaysia, 2021-06-12 作者: Hua, Wang; He, Bian; Lei, Yang; Hui, Zhang; Zhong, CaoJian \| 收藏 \| 浏览/下载：63/0 \| 提交时间：2021/11/08 imaging system real-time ultra-low light
	ROIC for HgCdTe e-APD FPA 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2013: Low-Light-Level Technology and Applications,, Beijing, 2013-06-27 - 收藏 \| 浏览/下载：21/0 \| 提交时间：2014/11/11 e-APD ROIC linear-mode ultra-low light imaging passive/active imaging
	ROIC for gated 3D imaging LADAR receiver 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging:Infrared Imaging and Applications, Beijing, 2013-06-25 - 收藏 \| 浏览/下载：15/0 \| 提交时间：2014/11/11 e-APD ROIC linear-mode active imaging ultra-low light imaging 3D-LADAR
	Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：61/0 \| 提交时间：2013/03/25 The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope the structure should have high stiffness and high reliability and light weight. Compared with invar aluminum alloy and titanium alloy carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages such as ultra-light weight high stiffness and dimensional stability etc. The optimization method and the baffle design can be helpful to other coaxial telescopes such as Cassegrain Gregorian and their subdivisions. 2012 IEEE.
	Research on automatic Hartmann test of membrane mirror (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang P. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror the surface configuration must be tested. However membrane mirror's shape is always changed by variable voltages on the electrodes and the optical properties of membrane materials using in our experiment are poor so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source CCD camera splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Tandem electroabsorption modulators integrated with DFB laser by ultra-low-pressure selective-area-growth MOCVD for 10 GHz optical short pulse generation 期刊论文 OAI收割 semiconductor science and technology, 2005, 卷号: 20, 期号: 8, 页码: 882-885 Zhao, Q; Pan, JQ; Zhang, J; Zhou, GT; Wu, J; Wang, LF; Wang, W 收藏 \| 浏览/下载：119/47 \| 提交时间：2010/03/17 摘要: A novel device of tandem MQW EAMs monolithically integrated with a DFB laser is fabricated by an ultra-low-pressure (22 mbar) selective area growth MOCVD technique. Experimental results exhibit superior device characteristics with low threshold of 19 mA output light power of 4.5 mW and over 20 dB extinction ratio when coupled to a single mode fibre. Moreover over 10 GHz modulation bandwidth is developed with a driving voltage of 2 V. Using this sinusoidal voltage driven integrated device 10 GHz repetition rate pulse with an actual width of 13.7 ps without any compression elements is obtained.