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Optimized design and research for cylindrical electrically controlled box of space camera 会议论文
7th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, AOMATT 2014, April 26, 2014 - April 29, 2014, Harbin, China
Wang H.-P.; Li Y.-C.; Dong J.-H.; Guo Q.-F.; Wang K.; Wang Y.-J.
收藏  |  浏览/下载:13/0  |  提交时间:2015/04/27
Laser cleaning of neutral attenuator plate based on low power laser diode 会议论文
2nd International Conference on Energy, Environment and Sustainable Development, EESD 2012, October 12, 2012 - October 14, 2012, Jilin, China
Gan X.; Chen Y.; Li L.
收藏  |  浏览/下载:16/0  |  提交时间:2014/05/15
Laser cleaning of neutral attenuator plate based on low power laser diode (EI CONFERENCE) 会议论文
2nd International Conference on Energy, Environment and Sustainable Development, EESD 2012, October 12, 2012 - October 14, 2012, Jilin, China
Gan X.; Chen Y.; Li L.
收藏  |  浏览/下载:19/0  |  提交时间:2013/03/25
Laser cleaning is a non-contact  green and environmental cleaning method  which can effectively remove particulate contaminations of sizes as small as 0.1 m without damage to the optics. But most laser cleaning devices are large and heavy  also expensive due to using large lasers such as CO2 laser  YAG Laser etc. In this work a low power LD was tried to clean fingerprint and dust contaminated on the surface of the attenuator glasses plates. In the laser cleaning experiment with low power diode the fingerprint grease can be efficient to be cleaned  but there is no evident effect for cleaning inorganic dust. The cleaning different degree of fingerprint contaminations was investigated at the variable laser parameters  including laser power and irradiation time. An optical microscope was used to analyze the cleaning effect. The results show that low power LD can effectively remove the fingerprint on the surface of absorptive-type attenuator glass plates. On the premise that the attenuator optics glasses are not damaged  the cleaning area increases with the increase of radiation time and laser power. The cleaning area doesn't change much with the variation of laser frequency when the other parameters are the same. (2013) Trans Tech Publications  Switzerland.  
Lightweight design of large scale theodolite's turntable based on topology optimization of continuum structure (EI CONFERENCE) 会议论文
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
San X.; Wang Y.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
In order to solve the problem that the weight of large scale theodolite's casting or steel plate welded structure is too heavy  lightweight design of large scale turntable based on topology optimization of continuum structure is investigated. Topology optimization could have better optimization efficiency because it can provide the optimized distribution of material and gain optimized structure in conceptual design phase of the structural design. In order to obtain lightweight and high stiffness structure  a truss turntable based on topology optimization of continuum structure is presented  and the validity of this lightweight structure is examined by finite element analysis. Comparing to the traditional welding steel turntable  the lightweight turntable  without changing the static displacement  can lose 386.48 kg(lightweight ratio is 26.7%)  and its first-order natural frequency raises from 167.02Hz to 173.71Hz. Meanwhile  in other aspects this turntable also has better performance than traditional structure. 2012 IEEE.  
Research on load-bearing characteristics of precision air-bearing rotary stage (EI CONFERENCE) 会议论文
3rd international Conference on Manufacturing Science and Engineering, ICMSE 2012, March 27, 2012 - March 29, 2012, Xiamen, China
Lin J.; Wang L.; Gao M.; Ran T.
收藏  |  浏览/下载:103/0  |  提交时间:2013/03/25
Air-bearing is a core component of air-bearing rotary stage. The weakness that the air-bearing has the low load capacity and stiffness has been concerned about by domestic and foreign scholars. So how to improve the load capacity and stiffness has become a serious problem. In order to improve the load capacity and stiffness of the air-bearing rotary stage  in this paper  we improved structure of Zhang Wenjie and others' high-precision direct-drive air-bearing rotary stage. The gas film of air-bearing has been meshed by GAMBIT software  and we use FLUENT software to obtain the carrying capacity features of the gas film. Finally  the structural static force of the precision air-bearing rotary stage will be analyzed by ANSYS software. The analysis results show that: the structural design of the precision air-bearing rotary stage is reasonable  and this structure can provide a larger range of loads. Even in heavy load conditions  a larger deformation will not occur any more. It has a good practical value  and also can be widely used in high precision equipments. (2012) Trans Tech Publications.  
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载:37/0  |  提交时间:2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
The research of control strategy on AOD furnace tilting system (EI CONFERENCE) 会议论文
2010 International Conference on Logistics Systems and Intelligent Management, ICLSIM 2010, January 9, 2010 - January 10, 2010, Harbin, China
Ma H. T.; You W.; Chen T.
收藏  |  浏览/下载:12/0  |  提交时间:2013/03/25
Blind channel estimation of MIMO-OFDM based on FDPM (EI CONFERENCE) 会议论文
5th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2009, September 24, 2009 - September 26, 2009, Beijing, China
Gang W.; Ming Z.; Hua C.
收藏  |  浏览/下载:12/0  |  提交时间:2013/03/25
The replacement of dry heat in generic reliability assurance requirements for passive optical components (EI CONFERENCE) 会议论文
ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China
Ren X.; Qian L.; Zhang G.
收藏  |  浏览/下载:11/0  |  提交时间:2013/03/25
According to Generic Reliability Assurance Requirements for Passive Optical Components GR-1221-CORE (Issue 2  January 1999)  reliability determination test of different kinds of passive optical components which using in uncontrolled environments is taken. The test condition of High Temperature Storage Test (Dry Test) and Damp Test is in below sheet. Except for humidity condition  all is same. In order to save test time and cost  after a sires of contrast tests  the replacement of Dry Heat is discussed. Controlling the Failure mechanism of dry heat and damp heat of passive optical components  the contrast test of dry heat and damp heat for passive optical components (include DWDM  CWDM  Coupler  Isolator  mini Isolator) is taken. The test result of isolator is listed. Telcordia test not only test the reliability of the passive optical components  but also test the patience of the experimenter. The cost of Telcordia test in money  manpower and material resources  especially in time is heavy burden for the company. After a series of tests  we can find that Damp heat could factually test the reliability of passive optical components  and equipment manufacturer in accord with component manufacture could omit the dry heat test if damp heat test is taken first and passed.  
Theoretical analysis of 980nm high power Vertical External-cavity Surface-emitting Semiconductor Laser (VECSEL) (EI CONFERENCE) 会议论文
ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China
He C.-F.; Lu G.-G.; Shan X.-N.; Sun Y.-F.; Li T.; Qin L.; Yan C.-L.; Ning Y.-Q.; Wang L.-J.
收藏  |  浏览/下载:15/0  |  提交时间:2013/03/25
By using bottom-emitting structure  we will develop laser diode (LD) pumped 980 nm VECSEL with active region of InGaAs/GaAsP/AlGaAs system. Because the thickness of barrier layer and absorption layer exceed that of quantum well  single well approximation model (KP method) can be used to calculate the band structure of VECSEL. The Schrodinger equation of finite deep potential well can be adopted to calculate the energy level structures of electron  heavy and light holes. According to the transition selection rule  we theoretically obtained the emitting wavelength of VECSEL and calculated quasi-Femi energy of valence band and conduction band based on the analysis of energy level structure of electron and holes. By analyzing the gain of strained quantum wells  we calculated the gain of VECSEL using transition matrix elements of electron  heavy and light holes. We give out the threshold gain  output power and other characteristic parameters. We will study the configuration of VECSEL and pumping scheme. We designed external cavity mirror  active region and bottom-emitting structure. A LD-pumped vertical external cavity surface-emitting laser whose output power is greater than 1.0 W can be predicted.  


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