CORC

浏览/检索结果: 共4条,第1-4条 帮助

限定条件                    
已选(0)清除 条数/页:   排序方式:
Remote Sensing Image Restoration with Modulation Transfer Function Compensation Technology In-orbit 会议论文
Conference Location, 2013
Mu X.; Xu S. Y.; Li G. X.; Hu J.
收藏  |  浏览/下载:13/0  |  提交时间:2014/05/22
Design and demonstration of micro multi-step mirrors and light source in micro FTIR (EI CONFERENCE) 会议论文
6th IEEE International Conference on Nano/Micro Engineered and Molecular Systems, NEMS 2011, February 20, 2011 - February 23, 2011, Kaohsiung, Taiwan
Liang Z.; Fu J.; Feng C.; Liang J.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
To obtain high resolution  high signal-to-noise ratio (SNR)  high reliability and real time in wide spectral range  we study the space modulation Micro Fourier Transform Spectrometer (FTS) based on multi-step mirrors covering the spectral range of 3-5m and 8-12 m in theory and experiment. The influences of spectrum reconstruction caused by the diffraction and extended light source in Fourier Transform Infrared Spectrometer (FTIR) are analyzed. A method to reduce the noises in spectrum reconstruction and the relationship between coherent intensity and solid angle of light source are discussed. An extended light source with suitable size is chosen  considering the requirement of SNR and spectrum resolving power in the optical design. Furthermore  the fabrication of micro multi-step mirrors  which is the core part of FTS  is investigated. Three methods for fabricating multi-step micro mirrors are demonstrated. 2011 IEEE.  
High precision test method for dynamic imaging of space camera (EI CONFERENCE) 会议论文
2010 IEEE International Conference on Advanced Computer Control, ICACC 2010, March 27, 2010 - March 29, 2010, 445 Hoes Lane - P.O.Box 1331, Piscataway, NJ 08855-1331, United States
Zheng G.-F.; Ma S.-F.; Sun J.-G.; Jin L.-X.; Zhang K.
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/25
A test method for dynamic imaging of space TDICCD (Time Delay and Integration Charge Coupled Devices) camera was presented in this paper. The test method adopted the PLL (Phase Locked Loop) technology and CMAC (Cerebella Model Articulation Controller) friction compensation as control strategy. Furthermore  According to this method  a test system for dynamic imaging of space TDICCD camera was designed and implemented. The system simulated the movement of the ground objects relative to the space aerocraft  to validate the capability of image speed match and the dynamic imaging quality of TDICCD camera. The design adopted a precision turntable and a drift turntable to simulate the movement around the earth and the drift motion in different latitude due to the rotation of earth  of the aerocraft. The turntables were drived by permanent magnet torque motor which was powered by PWM (Pulse Width Modulation). The system adopted DSP (Digital Signal Processor) as the control core and reached a very high performance. The experimental results showed that the steady speed error was better than 0.01 % and the instantaneous speed error reached 0.0267%. The precision of the test system designed met the requirement for dynamic imaging of TDICCD camera. 2010 IEEE.  
A new method of image reconstruction with high resolution in X-ray coded aperture imaging (EI CONFERENCE) 会议论文
Laser-Generated, Synchrotron, and Other Laboratory X-Ray and EUV Sources, Optics, and Applications II, August 2, 2005 - August 4, 2005, San Diego, CA, United states
Hu J.; Cheng L.; Wu X.; Sun Y.; Bai Y.
收藏  |  浏览/下载:19/0  |  提交时间:2013/03/25
In the processing diagnosis of the inertia confinement fusion (ICF)  the ring coded aperture imaging technique is applied in order to gain high space and time resolutions simultaneously. The key of acquiring high spatial resolution is how to obtain a point spread function of an imaging system. The common method is the firsthand projection method which is an approximate one. The x-ray diffraction effect is neglected in the method  so the resolution of reconstructed image is decreased. We have derived the point spread function (PSF) of the ring coded aperture from scalar diffraction theory. And the Wiener filter is fabricated on the basis of the PSF. In National Key Laboratory of Laser Fusion  at China Academy of Engineering Physics  the imaging experiment on the diagnosis of ICF is completed using the ring coded aperture plate with inner diameter d1 = 250m and outer diameter d2 = 260m . The obtained coded image is processed by the Wiener filter which diffractive effect is considered. The processed results have shown that resolution and modulation contrast of acquired image are evidently better than the results obtained by the firsthand projection method.  


©版权所有 ©2017 CSpace - Powered by CSpace