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Optical system design for lens with large relative aperture 会议论文  OAI收割
applied optics and photonics, china: optical design and manufacturing technologies, aopc 2015, beijing, china, 2015-05-05
作者:  Zhang, Kaisheng;  Zhang, Zhi;  Zhang, Zhaohui;  Wang, Zefeng;  Yan, Aqi
收藏  |  浏览/下载：26/0  |  提交时间：2016/01/05
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
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：47/0  |  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.  
An improved fast parallel SPIHT algorithm and its FPGA implementation (EI CONFERENCE) 会议论文  OAI收割
2010 2nd International Conference on Future Computer and Communication, ICFCC 2010, May 21, 2010 - May 24, 2010, Wuhan, China
作者:  Jin L.-X.;  Tao H.-J.;  Wu Y.-H.
收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25
In view of the current stringent need to the real-time compression algorithm of the high-speed and high-resolution image  such as remote sensing or medical image and so on  in this paper  No List SPIHT (NLS) algorithm has been improved  and a fast parallel SPIHT algorithm is proposed  which is suitable to implement with FPGA. It can deal with all bit-planes simultaneously  and process in the speed of 4pixels/period  so the encoding time is only relative to the image resolution. The experimental results show that  the processing capacity can achieve 200MPixels/s  when the input clock is 50MHz  the system of this paper need 2.29ms to complete lossless compression of a 512x512x8bit image  and only requires 1.31ms in the optimal state. The improved algorithm keeps the high SNR unchanged  increases the speed greatly and reduces the size of the needed storage space. It can implement lossless or lossy compression  and the compression ratio can be controlled. It could be widely used in the field of the high-speed and high-resolution image compression. 2010 IEEE.  
Validation of soil moisture retrieval in arid and semi-arid areas 期刊论文  OAI收割
Shuikexue Jinzhan/Advances in Water Science, 2010, 卷号: 21, 期号: 2, 页码: 201-207
Li, Qin1, 2; Chen, Xi1; Veroustraete, Frank3; Bao, An-Ming1; Liu, Tie4; Wang, Jin-Lin1, 2
收藏  |  浏览/下载：37/0  |  提交时间：2011/08/19
Annular sub-aperture stitching interferometry for testing of large asphreical surfaces (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China
作者:  Zheng L.-G.;  Zhang X.-J.
收藏  |  浏览/下载：78/0  |  提交时间：2013/03/25
Annular subaperture stitching interferometric technology can test large-aperture  and the PV and RMS of residual error of the full aperture phase distribution is 0.027 and 0.0023  high numerical aperture aspheric surfaces with high resolution  the relative error of PV and RMS is -0.53% and -0.31%  respectively. The results conclude that this splicing model and algorithm are accurate and feasible. So it provides another quantitive measurement for test aspheric surfaces especially for large aperture aspheres besides null-compensation.  low cost and high efficiency without auxiliary null optics. In this paper  the basic principle and theory of the stitching method are introduced  the reasonable mathematical model and effective splicing algorithm are established based on simultaneous least-squares method and Zernike polynomial fitting. The translation errors are eliminated from each subaperture through the synthetical optimization stitching mode  it keeps the error from transmitting and accumulating. The numerical simulations have been carried on by this method. As results  the surface map of the full aperture after stitching is consistent to the input surface map  the difference of PV error and RMS error between them is -0.0074 and -0.00052 ( is 632.8nm)  respectively  
A study of time over threshold (TOT) technique for plastic scintillator counter 期刊论文  OAI收割
CHINESE PHYSICS C, 2008, 卷号: 32, 期号: 3, 页码: #REF!
作者:  
收藏  |  浏览/下载：98/0  |  提交时间：2016/04/12
A study of time over threshold (TOT) technique for plastic scintillator counter 期刊论文  OAI收割
中国物理C, 2008, 期号: 3, 页码: 186-190
作者:  Wu JJ(吴金杰);  Heng YK(衡月昆);  Sun ZJ(孙志嘉);  Wu C(吴冲);  Zhao YD(赵玉达)
收藏  |  浏览/下载：21/0  |  提交时间：2015/12/21
Research on the affect of differential-images technique to the resolution of infrared spatial camera (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China
Jin G.; An Y.; Qi Y.; Hu F.
收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25
The optical system of infrared spatial camera adopts bigger relative aperture and bigger pixel size on focal plane element. These make the system have bulky volume and low resolution. The potential of the optical systems can not be exerted adequately. So  one method for improving resolution of infrared spatial camera based on multi-frame difference-images is introduced in the dissertation. The method uses more than one detectors to acquire several difference images  and then reconstructs a new high-resolution image from these images through the relationship of pixel grey value. The technique of difference-images that uses more than two detectors is researched  and it can improve the resolution 2.5 times in theory. The relationship of pixel grey value between low-resolution difference-images and high-resolution image is found by analyzing the energy of CCD sampling  a general relationship between the enhanced times of the resolution of the detected figure with differential method and the least count of CCD that will be used to detect figure is given. Based on the research of theory  the implementation process of utilizing difference-images technique to improve the resolution of the figure was simulated used Matlab software by taking a personality image as the object  and the software can output the result as an image. The result gotten from the works we have finished proves that the technique is available in high-resolution image reconstruction. The resolution of infrared spatial camera can be improved evidently when holding the size of optical structure or using big size detector by applying for difference image technique. So the technique has a high value in optical remote fields.  
A new software method for accurate mass measurements of drugs on unit mass resolution mass spectrometer 期刊论文  OAI收割
Acta Pharmaceutica Sinica, 2007, 卷号: 42, 期号: 10, 页码: 1112-1114
作者:  LIU Ke;  MA Bin;  WANG Yongdong;  CHEN Xiaoyan;  ZHONG Dafang
  |  收藏  |  浏览/下载：23/0  |  提交时间：2019/01/08