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	Research on station mode for attitude determination of multiple targets (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computational and Information Sciences, ICCIS2010, December 17, 2010 - December 19, 2010, Chengdu, Sichuan, China 作者: Zhao L.; Wang J.; Li M. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 A key problem of attitude determination system is how to locate CMOS cameras and deal with relations among them. In this paper several kinds of multi-CMOS station mode are introduced. Fundamental principles and classification of station mode directly affect on measurement parameters of system. No matter what mode is designed the ultimate goal is to extend Effective Viewing Field (EVF) increase capture ratio of objects and increase measurement precision. Station mode introduced in this paper is made of CMOS cameras because of low cost high speed frame frequency and low power consumption CMOS cameras were putted near from object tested. So sequences of image are legible which are convenient for analysis of three dimensional(3D) attitude. 2010 IEEE.
	Micro-motion exposure method based on PZT piezoelectric ceramics (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China 作者: Meng Z.; Meng Z. 收藏 \| 浏览/下载：105/0 \| 提交时间：2013/03/25 There mainly is laser digital photofinishing technique and digital photofinishing technique based on LCD consisting of TFT and LCOS in the digital photofinishing field at the present time. The former have a good many merit such as wide color gamut high processing rate large output size and high brightness but his cost is very high his maintain technique being comparatively complex that result in difficult use for people. The utilization ratio of the latter is low because of lower resolution and lower aperture ratio for LCD but the digital photofinishing based on LCD have lower cost and higher utilization ration being suitable for people's current standard of living. Considering above mentioned problem a micro-motion exposure method based on PZT piezoelectric ceramics used in digital image photofinishing is presented. The two-dimension micro-motion exposure system consisting of PZT piezoelectric ceramics LCD panel polarizing film and spring strip is designed. By means of PZT piezoelectric ceramics the LCD panel is removed about the one half of the pixel size of the LCD panel for four times from the original place at the same time imaging system is exposed four times at the printing paper. The software is used to control the time synchronization the exposure time and motion range of the LCD panel. The system has advantages such as shorter response time than 0.1seconds lesser motion error than 0.01 microns high stability and repeatability. Experimental results show that the proposed micro-motion exposure method improve the picture brightness and enlarge output size at the meantime reducing the cost of the system. 2009 SPIE.
	Application of CMOS APS star tracker with large FOV in attitude and angular velocity determination (EI CONFERENCE) 会议论文 OAI收割 Advanced Sensor Systems and Applications III, November 12, 2007 - November 14, 2007, Beijing, China Lu D.; Guang J.; Shaoju W.; Tao C. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 The paper deals with the spacecraft attitude determination problem using a new kind of star tracker with large FOV based on CMOS APS. Star tracker has been developed since 1970s and proved to be the most accurate sensor ever used in the spacecraft attitude determination systems. But the traditional CCD star tracker also has some disadvantages such as small FOV high power consumption low sample rate and low working angular rate limit which prevent the use of CCD star tracker in attitude large angle maneuvering process. The new kind of star tracker based on CMOS APS has no such disadvantages and is more applicable on modern low-cost agile small satellites. Its higher sample rate and working angular rate limit over traditional CCD star tracker make it more adapt for spacecraft angular velocity determination. Because of the large FOV of the star tracker the mathematical model of traditional CCD star tracker with a small FOV is not appropriate. So a new mathematical model was quoted to fit the star tracker with a large FOV. An alternative adaptive algorithm was also introduced in the paper. It can help the EKF algorithm work lacking of accurate covariance of the observation noise. An optimal estimation algorithm was used to estimate the angular velocity directly from the star tracker measurements. Mathematic simulation results indicate the CMOS APS star tracker can give accurate attitude information and estimated angular rate. The method can be used as the chief attitude determination system design of low-cost satellite without gyros or be used as a backup strategy in the event of gyro failures to enhance the reliability of the attitude determination system.
	Support technique of ultra thin mirror in space optics (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, November 2, 2005 - November 5, 2005, Xian, China 作者: Ren J.-Y.; Gao M.-H. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 With the development of space optical system the technique of ultra thin mirror come forth and is paid more attention because of less difficulty in machining low cost lightweight no disassembly during detecting and maintaining. The key technique takes advantage of deformation of ultra thin mirror as the influence of environment to adjust the surface figure. Its accuracy meets requirement. An analysis method is based on finite element analysis (FEA) and many items including the amount of support points the way of arrangement the optimum design of support component are studied. The finite element method was used to analyze the mirror and some different mirror support schemes. The principal aim of the mirror analysis is to get numbers of support points and the ways of the support. There are three schemes including 12-6-1 12-8-1 and 16-8-1 models. Deformation of deadweight is calculated under the three conditions. The way of 16-8-1 is more suitable than the designs of other two. The support subassembly is amended to meet with the mirror surface RMS in the range of 30m. Deformation of the mirror with support structure has been calculated. The result is 16.52nm lower than a quarter of the wavelength which indicates the feasibility of the support scheme applied to mirror. Theoretical result for the best way of support is presented. The result of analysis shows that requirement surface figure could be met through adjusting support points. It predicts feasibility of the support technique and provides theoretical value for active adjustment in the laboratory. At present support and adjusting experiment of ultra thin mirror is being carried on.
	Packaging technology of polymer/Si arrayed waveguide grating and their environmental stability (EI CONFERENCE) 会议论文 OAI收割 2005 6th International Conference on Electronics Packaging Technology, August 30, 2005 - September 2, 2005, Dameisha, Shenzhen, China 作者: Zhang Y.; Zhang X.; Zhang X.; Zhang X.; Wang F. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 Future optical communication systems will use more of the exceptional high bandwidth of optical fiber. Wavelength division multiplexing (WDM) systems are well suited to transport terabits of information via the fiber[1]. Multiplexers/ demultiplexers (MUX/DEMUX) are essential components for dense WDM systems. Several different kinds of multiplexer types have been developed in the past: (a) interference filters (b) fiber gratings and (c) planar lightwave circuit (PLC) MUX/DEMUXers[2 3]. The planar fabrication process of the last mentioned PLCs allows the realization of high performance filters with a large number of wavelength channels. Further an integration with other optical elements seems to be possible. Arrayed waveguide gratings (AWG) are a special kind of PLC-MUX/DEMUXers which are very attractive components for WDM systems because of their great flexibility in filter design[4 5]. Basically an AWG is an optical spectrograph built in planar waveguide technique. Typically AWGs works in a high grating order (50-250). For AWG multiplexer applications in communications systems a precise wavelength controllability and wavelength stability with long term is demanded. Recently a polymeric (especially fluorinated polymer with low optical absorption loss in the infrared region) AWG has attracted much attention because of its easy fabrication low cost possibility and a potential of integration with other polymer devices[6]. Standard AWGs however show a change of center wavelength with temperature. A method to prevent this temperature drift is to package the AWG together with a temperature controller in order to tune and fix the desired filter-wavelength. In this paper a 32-channel AWG was fabricated using a cross-linkable fluorinated poly (ether ether ketone) (FPEEK) its package technology and environmental stability were also discussed. 2005 IEEE.