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	Structural design of zoom system based on linear motor 会议论文 OAI收割 Beijing, China, 2019-07-07 作者: Yang, Xiaofan; Yang, Hongtao \| 收藏 \| 浏览/下载：37/0 \| 提交时间：2020/03/04 Zoom camera Structural design Optimization analysis Optical axis angle
	Effect of gimbal point displacement on optical axis pointing precision in an image seeker (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 A concentric glass spherical dome was usually chosen as the transparent window mounted in front of the optical lens in an image seeker. However optical ray had to change its direction when propagating through the dome due to refraction unless passing through the center of the dome which demanded gimbal point coincide with the center of the dome exactly. In fact gimbal point displacement could not be eliminating due to fabrication assembly and vibration therefore the optical axis pointing error generated. In this paper the effect of gimbal point displacement on optical axis pointing precision in an image seeker was analyzed and the theoretical expression of the optical axis pointing error was derived based on geometric optics and the error dynamics was explored by numerical. Take a visible light image seeker as a case the thickness of concentric glass spherical dome was 8mm and the inner radius was 72mm and the optical axis pointing errors varying dynamically with the look angle and the gimbal point displacement were shown in graph. When the gimbal displacement was 0.11mm the maximum optical axis pointing error was 0.054mrad that is equal to the instantaneous field of view (IFOV) corresponding to the camera system whose focal length was 120mm and pixel size was 6.5m. Furthermore with the gimbal displacement increasing the optical axis pointing error increased linearly. The analyzed results provided a theoretical basis for the displacement range which had to be limited strictly in the gimbal design process. 2011 IEEE.
	The research of H mixed sensitivity method for line-of-sight stabilization for Carrier-Based theodolite (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 Hua C. L.; Bin G. H.; Mei Z. S. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 In view of the requirements of isolating disturbances and stabilizing optical axis of Carrier-Based theodolite A two-axis stabilizated platform system with the rate gyro was designed The expressions of line-of-sight add-angle velocity begotten by ship-swaying is introduced The principles of selection of weighting of fuctions are brought and adopting H Mixed Sensitivity Method in the velocity Stabilization-loop. 2010 IEEE.
	The method on the measurement of the aircraft attitude by the spatial cosines relationship of the single station and planes to the intersection the multi-station of electro-optical theodolite (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 Zhao L.-R.; Cao Y.-G. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 In order to realize the aircraft attitude measurement The paper advances electro-optical theodolite methods of measuring the aircraft attitude by using the spatial cosines relationship the single station theodolite and how to use intersection of the multi-station theodolite. The single station theodolite was introduced in a measured distance from the aircraft posture information. An exhaustive approach was used to access to the aircraft axis of the feature points and the location in the space was used to obtain space posture parameters. The multi-station theodolite was introduced to get the information of the aircraft flight attitude by method of using planes to the intersection. Two-dimensional image to obtain objective axis by fitting algorithm using Hough transform. And then Calculate the vertical distance of the origin to the target of the central axis and the origin to the target of the central axis of the angle between the normal and the X-axis obtaining the linear equation in the two-dimensional plane. Two-dimensional axis of the target image and the camera system's optical center only identified a space plane. The aircraft yaw axis angle and pitch angle can be obtained by getting the space axis using plains to the intersection method. Experimental results show that attitude angle error of the single station theodolite is less than 1 when its distance is less than 6000m and attitude angle error of the multi-station theodolite is less than 0.6 when its intersection angle is between 30 and 150. In this paper according to test result of precision comparing the mathematical model is correct and the algorithm is reasonable in extracting effective parameters of the aircraft's attitude. 2010 IEEE.
	Influence of spatial temperature distribution on high accuracy interferometric metrology (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: Yang H.; Zhang J.; Zhang J.; Zhang J.; Yan F. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 We calculate the influence of temperature change on the refractive index of air establish a model of air temperature distribution and analyze the effect of different temperature distribution on the high accuracy interferometric metrology. First a revised Edlen formula is employed to acquire the relation between temperature and refractive index of air followed by introducing the fixed temperature gradient distribution among the spatial grid within the optical cavity between the reference flat and the test flat of the Fizeau interferometer accompanied by a temperature change random function within each grid. Finally all the rays through the air layer with different incident angles are traced by Matlab program in order to obtain the final output position angle and OPD for each ray. The influence of different temperature distribution and the length of the optical cavity in on the testing accuracy can be analyzed through the RMS value that results from repeatable rays tracing. As a result the horizontal distribution (vertical to optical axis) has a large effect on the testing accuracy. Thus to realize the high accuracy figure metrology the horizontal distribution of temperature must be rigorously controlled as well as to shorten the length of the optical cavity to a large extent. The results from our simulation are of great significant for the accuracy analysis of interferometric testing and the research of manufacturing a interferometer. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Small roll angle measurement based on auto-collimation and moire fringe (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology - Optoelectronic Measurement Technology and Systems, October 19, 2009 - October 22, 2009, Shanghai, China Bai X.-G.; Cai S.; Qiao Y.-F.; Dai M. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 A novel method for small roll angle measurement based on auto-collimation and moire fringe is presented. A right-angle prism is used as an indicator of small roll angle around the optical axis and a CCD is used to collect moire fringes that are generated by scale grating image which is reflected by prism and index grating. Any small roll angle of the prism will change the include angle of the grating pair and meanwhile induce a change in the moire fringe period. The relationship between roll angle and period of moire fringes is established. The period data is obtained by image processing. The experimental result certifies that the principle of small angle measurement method based on auto-collimation and moire fringe is correct and feasible. The measuring error is smaller than 0.2 within 7 range compared with 0.2 autocollimator. 2009 SPIE.