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Optimal PSF Estimation for Simple Optical System Using a Wide-Band Sensor Based on PSF Measurement 期刊论文  OAI收割
SENSORS, 2018, 卷号: 18, 期号: 10, 页码: 11
作者:  
Xu, Mingfei;  Pan, Yun;  Huang, Wei;  Zheng, Yunda
  |  收藏  |  浏览/下载:31/0  |  提交时间:2019/08/21
Real-time video compressing under DSP/BIOS (EI CONFERENCE) 会议论文  OAI收割
MIPPR 2009 - Medical Imaging, Parallel Processing of Images, and Optimization Techniques: 6th International Symposium on Multispectral Image Processing and Pattern Recognition, October 30, 2009 - November 1, 2009, Yichang, China
Chen Q.-P.; Li G.-J.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
This paper presents real-time MPEG-4 Simple Profile video compressing based on the DSP processor. The programming framework of video compressing is constructed using TMS320C6416 Microprocessor  the architecture level optimizations are used to improve software pipeline. The system used DSP/BIOS to realize multi-thread scheduling. The whole system realizes high speed transition of a great deal of data. Experimental results show the encoder can realize real-time encoding of 768*576  TDS510 simulator and PC. It uses embedded real-time operating system DSP/BIOS and the API functions to build periodic function  25 frame/s video images. 2009 Copyright SPIE - The International Society for Optical Engineering.  tasks and interruptions etcs. Realize real-time video compressing. To the questions of data transferring among the system. Based on the architecture of the C64x DSP  utilized double buffer switched and EDMA data transfer controller to transit data from external memory to internal  and realize data transition and processing at the same time  
Novel method for optimizing polishing tool-path in CCOS based on weighted-iterative algorithm (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Zhang X.-J.;  Wang X.;  Wang X.;  Wang X.;  Wang X.-K.
收藏  |  浏览/下载:39/0  |  提交时间:2013/03/25
In Computer Controlled Optical Surfacing (CCOS)  polishing tool-path is the base of solving other control parameters such as dwell time. In order to improve the fabrication results of polishing off-axis aspheric  a novel method to optimize the tool-path is discussed in this paper. The optimizing method named weighted-iterative algorithm is according to the balance principle of the particle system. The power factor of each dwell point represents the requirement of dwell density. Considering the factors which influence the polishing result  the power factors cosist of three elements include constant  error distribution and dwell distance of workpiece edge. The tool-path is solved by numerical iterative method. In the end  an error data is simulated with actual parameters using the matrix-based algorithm with two different tool-paths. The one is X-Y uniform spacing model and the other one is to optimize it based on the first. The comparison shows that the results of the optimized one are much better than traditional one  especially the rms convergence rate. Theory of the algorithm is simple and exercisable  and it satisfies practical requirement as well. 2009 SPIE.  
Optical system of large relative aperture and wide field using aspheric corrector for detecting (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Zhang J.;  Zhang J.;  Zhang J.;  Wang J.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
The magnitude requirement of space target detecting determines that the image of detecting telescope should have several performances: small spots  the wider field of view  small 80% encircled energy diameter and good MTF(Modulation transfer function). So the aperture and field of view of optical system have some demands accordingly. The larger aperture  the more extensive range which the telescope searches. Now most of ground telescopes whose apertures are from 500mm to 1000mm is on-axis optical system  the more energy that telescope collects and higher magnitude the telescope detects  so wide field of view becomes the most importance problem. To obtain large relative aperture and wide field of view  the paper introduces a catadioptric telescope with small aperture aspheric refractive corrector  whose conic surface will be used to remove the aberrations due to large relative aperture and wide field of view. As to the optical system  there is only one aspheric refractive corrector  and it is relatively easy for manufacturing because of its concave figure and normal material. The paper gives the example  and optimizes this optical system with ZEMAX program. And then the paper provides a specific analysis program for testing the aspheric refractive corrector. The aperture of this optical system is 750mm  and its relative aperture is 0.82  and the field of view is 3.6 diameter(diagonal). Its structure is simple and the image quality is also very good. 2009 SPIE.  
Design of high-resolution fourier transform lens (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Zhang L.;  Zhang L.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
With the development of optical information processing  high-resolution Fourier transform lens has often been used in holographic data storage system  spatial filtering and observation of particles. This paper studies the optical design method of high-resolution Fourier transform optical lenses system  which could be used in particles observation and holographic data storage system. According to Fourier transform relation between object and its frequency plane and the theory of geometrical optics  the system with working wavelength 532nm and resolution 3 m was designed based on ZEMAX. A multi-configuration method was adopted to optimize the system's lenses. In the optical system  a diaphragm was placed at the system's spectrum plane and the system demanded a low vacuum to cut down the influences of atmosphere and other particles. The result of finite element analysis indicated that the influences of vacuum pumping to optics spacing and mirror surface shape very minor  and the imaging quality not being affected. This system has many advantages  such as simple structure  good image quality and a high resolution of 3 m. So it has a wide application prospect and can be used both in holographic data storage system and particles observation.  
Design of dual-FOV refractive/diffractive LWIR optical system (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Wang L.-J.;  Zhang J.-P.;  Wang L.-J.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
An infrared-optical zoom system using binary element is proposed in this paper. The two main advantages of the zoom system introducing here are: bigger F-number and lower cost. The primary optical properties are: F/#=1  Second  Others  zoom ratio =1:4  binary element is used to correct the chromatical aberration by taking the advantage of negative dispersion characteristics and the cost of the system is lower than that of conventional ones with Zinc Selenide (Znse) material at the same level. In the binary element is rotational symmetric with one step which is easy to fabricate  in order to balance 5th spherical aberration  and dual field are 26.6 and 5.6respectively. Wider field of view is used for search and the smaller one is used for imaging details. This system uses un-cooled infrared detector with 320240 pixels and 45m pixel size. The F-number matches the sensitivity range of the detector array. Three aspects are considered during design process to make the system more satisfactory and more achievable. First  5th coma aberration and 5th astigmatic aberration  the manner of zoom is accomplished by exchanging tow lenses into the smaller field of view system layout. The lens exchange manner faces the requirement of simple system structure and good image quality in both focal points. It can also make the system more feasible in the alignment process than mechanical-zooming manner and optical-zooming manner  high-order asphere surfaces with 2th order to 10 th order are also hired in the system. Asphere surface is useful in compressing the system and improving optical system transmittance. This kind asphere surface is on industrial level featuring low cost and easy to fabricate. It is shown that good image quality can achieved by implementing five Germanium lenses and the transmittance of system is 72%. All aberrations are diffraction-limited  both spherical aberration and astigmatic aberration are corrected. When the field of view(FOV) is 26.6 and the focal length is 152mm  MTF at Nyquist frequency(11lp/mm) is great than 0.7. The spherical aberration is -0.0073. The coma aberration is 0.0978 and the astigmatic aberration is -0.013. When the field of view(FOV) is 5.6 and the focal length is 38mm  MTF at Nyquist frequency is great than 0.8 with spherical aberration -0.0046  the coma aberration 0.055 and astigmatic aberration 0.034.  
Self Imaging technique for refocusing an aerospace camera (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Li W.;  Li W.;  Wang X.;  Wang X.;  Wang X.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
A novel auto-focusing technique using a self imaging approach is developed for an aerospace camera having large aperture and long focus. Its optical system consists of an emitting system  receiving system  and two penta-prisms. Emitting system has three parts: a light source  beamsplitter  and aim slit. The receiving system includes a field lens  two separate lenses  and CCD. Using two little penta-prisms instead of a large planar mirror makes the autofocus system simple and compact. CCD was used as photoelectric converting device. A defocused signal is acquired by measuring the change of the two slit self-images position imaged on the CCD. A simple and compact construction of the auto-focusing system was proposed. The algorithm to calculate the moving of the slit-self images position was analyzed in order to achieve subpixel position estimation. The results of the experiments show a 10m focusing precision. The system demonstrates high resolution  easy adjustment and high reliability.