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	Influences of group velocity dispersion on ultrafast pulse shaping in time lens 期刊论文 OAI收割 PHYSICA SCRIPTA, 2019, 卷号: 94, 期号: 12 作者: Xie, Peng; Wen, Yu; Wan, Zishen; Wang, Yishan \| 收藏 \| 浏览/下载：177/0 \| 提交时间：2019/09/27 group velocity dispersion time lens signal processing integrated optics
	Design and analysis of auto-focus assembly for spaceborne remote sensing camera (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronics, Communications and Control, ICECC 2011, September 9, 2011 - September 11, 2011, Ningbo, China 作者: Chen W.; Gao X. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Spaceborne remote sensing camera may be out of focus when the environment and photographic distance changes. In order to get higher ground sampled distance for the camera based on the experience gained from the development of a remote sensing camera working principle of auto-focus assembly control system was discussed. Time of waveform extraction was reduced. It sets force an auto-focus assembly that uses cam and line guide rail in order to move the lens group. The motion error of the auto-focus assembly was difficult to be eliminated and would affect on the focusing accuracy of the spaceborne remote sensing camera directly. So it was analyzed at both ends of the focusing structure. The CCD detector can keep stable when the remote sensing camera is imaging. The motion error was tested to verify the validity of the simulation result and it is less than 0.01mm. Its accuracy meets using demand. The focusing method of moving focal plane is suitable for spaceborne remote sensing camera. 2011 IEEE.
	The research on distortion measurement and compensation technology in photoelectricity measurement system (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Hong F.; Mujun X.; Zhiqian W. 收藏 \| 浏览/下载：15/0 \| 提交时间：2013/03/25 The distortion made by optical lens largely affect the measurement accuracy of the large field of view photoelectricity measurement system according to the theory of aberration in the photoelectricity system this paper design a series of distortion measurement devices in connection with the process of distortion correction in photoelectricity system establish the related mathmatics model make the real time distortion correction by the method of software compensation. The experimental results demonstrate the method decrease the measurement error made by the photoelectricity system distortion after the compensation in tatal field of view the systematic measurement error is less than 0.5 picture element. 2010 IEEE.
	New LED illumination optical engine for micro-projection display (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China 作者: Meng Z.; Meng Z. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 A new optical engine consisting of LEDs rectangular CPC rectangular lens array and micro display chip DMD is designed by using of KOLA illumination algorithm for micro-projection display. Detail description and analysis of the rectangular CPC and rectangular lens array are provided. The influence due to the size of rectangular CPC and rectangular lens array is analysed for illuminance uniformity on the DMD chip and light energy efficiency of the optical engine system by software ZEMAX. Based on the analysis of parameter of rectangular lens array the size of rectangular lens array more decrease the illumination uniformity. Experimental results show that the proposed illumination light optical engine can obtain perfect rectangular focula with higher light uniformity more than 90 % and higher energy efficiency of 40 % to meet the needs of micro-projection display at the same time the designed illumination optical engine compared with other uniformizing light algorithm have advantages such as: lesser capacity high illumination uniformity. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Development and radiance calibration of three-waveband camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photonics and Optoelectronics, SOPO 2010, June 19, 2010 - June 21, 2010, Chengdu, China 作者: Wang J.; Liu Y.; Liu Y.; Sun Q.; Liu Y. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 An imaging system with three-waveband sharing one lens and an area CCD was developed. By rotating different filters into the beam path the required waveband was selected. The optical system which can image in ultraviolet visible and near infrared region was designed and the signal collecting system was integrated. The optical design and system integration have some advantages such as low cost small size and light in weight. To obtain a high imaging quality the radiation calibration is carried out in order to establish the relation between the average grey level of output image and the input radiance from the integrating sphere. According to the calibration data in experiments the radiation dynamic range and the best working point of the system are determined. The experiment result shows that the dynamic range of the image system is maximal when the exposure time is 8ms in ultraviolet 0.5ms in visible and 0.125ms in near infrared region. 2010 IEEE.
	Modeling and analysis of dialyte-lens auto-focusing technology for theodolite (EI CONFERENCE) 会议论文 OAI收割 2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China Wu L.-T.; Qiao Y.-F.; Wu D.-K.; Cai S. 收藏 \| 浏览/下载：14/0 \| 提交时间：2013/03/25 In order to realize real-time auto-focusing for theodolite lens-apart method was designed with the corresponding math model built and analyzed. An Object beam splitted after the first image surface of the theodolite traveled through two dialyte lens and then was imaged on CCD. The distance between two spots when exactly focused was set as the calibration value and the relationship between defocus distance and spot offset was given. The influence of tracking center shift and divergence angle etc. on focusing accuracy was analyzed. Compared with the traditional focusing method this scheme has a higher accuracy faster calculation higher tolerance for environment temperature and a simpler construction. The experiment result exhibited a resolution higher than 0.056mm which shows a bright engineering application prospect for this method. 2009 SPIE.
	Autofocusing technique based on image processing for remote-sensing camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2007 - Image Processing, September 9, 2007 - September 12, 2007, Beijing, China 作者: Wang X.; Xu S.-Y.; Wang X.; Wang X. 收藏 \| 浏览/下载：14/0 \| 提交时间：2013/03/25 The key to the auto-focusing technique based on image processing is the selection of focus measure reflecting image definition. Usually the measures derived are on the premise of the images acquired with the same scene. As for the remote-sensing camera working in linear CCD push-broom imaging mode the premise doesn't exist because the scenes shot are different at any moment which brings about difficulties to the selection of the focus measure. To evaluate the image definition the focus measure based on blur estimation for rough adjustment is proposed to estimate the focused position by only two different lens positions which greatly saves the auto-focusing time. Another evaluation function based on edge sharpness is developed to find best imaging position in the narrow range. Simulations show that the combination of the two measures has the advantages of rapid reaction and high accuracy.
	Research on the nonuniformity correction of linear TDI CCD remote camera (EI CONFERENCE) 会议论文 OAI收割 Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China Ya-xia L.; Zhi-hang H. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 Many applications such as industrial inspection and overhead reconnaissance benefit from line scanning architectures where time delay integration (TDI) significantly improves sensitivity[5]. Images with linear response have become the backbone of the imaging industry. But each pixel of the TDI CCD has unique light sensitivity characteristics. Because these characteristics and the lens of the optical system affect camera's linearization and its performance they must be removed through calibration. The process by which a CCD image is calibrated is known as nonuniformity correction. This paper discusses several methods of nonuniformity correction[2]. The first is one-point correction technique which requires only one calibration point. This approach is to shift each curve toward the nominal curve by subtracting the offset from or adding the offset to the average. The second is two-point correction technique which requires two calibration points. Each point is rotated and aligned so that all the detectors have the same response under the same radiance. The third is multipoint correction. It is recommended that more calibration points be implemented at appropriate regions of the response curve. Depend on the linear photoelectric response of the TDI CCD we use two-point calibration and the standard deviations for the images are given before and after the correction.
	Study on optical parts of MOEMS optical switch with low insertion loss (EI CONFERENCE) 会议论文 OAI收割 MEMS/MOEMS Technologies and Applications II, November 10, 2004 - November 12, 2004, Beijing, China 作者: Wang W.; Wang L.; Wang L.; Wang L.; Chen W. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 We study insertion losses of optical switch when the laser beam is propagating during the free space between two single mode fibers (SMFs) and the related assemblage challenges Then a new packaging structure is developed for the hybrid-integration of free-space MOEMS (micro-opto-electro-mechanical systems) chip with a silicon micromachined submount to improve alignment accuracy. The submount is designed to accommodate various free-space MOEMS chips with minimal active optical alignment thus reducing the packaging cost. The silicon submount has a central recess to place the MOEMS chip in sixteen V-grooves for optical fibers and micropits for micro ball lenses all bulk micromachined at the same time by a single anisotropic wet etching step. A corner compensation technique is employed to prevent erosion of the convex corners where different geometries meet. Through this assembling method the fiber micro ball lens can be aligned preciously thus reduced lateral and angular misalignment between them. Then total insertion losses can be decreased.