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	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：31/0 \| 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
	The effect on tolerance distributing of an off-axis three mirror anastigmatic optical system with wavefront coding technology (EI CONFERENCE) 会议论文 OAI收割 Optical System Alignment and Tolerancing II, August 10, 2008 - August 11, 2008, San Diego, CA, United states 作者: 收藏 \| 浏览/下载：53/0 \| 提交时间：2013/03/25 The wavefront coding technology is known as a system-level technology which can extend the depth of focus of optical system by innovative optical design and image restoration. This technology can control misfocus related aberrations including misfocus astigmatism and Petzval curvature temperature-related misfocus in digital imaging systems. It can also help optical system tolerate more residual error in optical manufacturing and alignment besides misfocus. The brief introduction of wavefront coding technology and the wavefront coded TMA system under research is presented respectively in part 1 and part 2. The "MTF similarity" is defined to describe the relationship among MTF at different position or different fields in the third part. It is also shown in this part that the MTF similarity of wavefront coded system is much higher than the normal system within a large range. In part 4 comparison between the origin system and the new system with wavefront coding technology is provided after multiple errors are introduced from which it can be observed that the system with wavefront coding technology can tolerate much bigger error than origin system. The error tolerance is re-distributed according to a new criterion based on MTF similarity. If the MTF similarity is less than a certain value it can be regarded that the system can tolerate the residual error. The new error tolerance is displayed and it is shown that the wavefront coding technology can also loosen the error distributing besides extended the depth of focus.
	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：46/0 \| 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.
	Controllable atom localization via double-dark resonances in a tripod system 期刊论文 OAI收割 j. opt. soc. am. b-opt. phys., 2006, 卷号: 23, 期号: 10, 页码: 2180, 2184 Cheng Dong-chao; 钮月萍; 李儒新; 龚尚庆收藏 \| 浏览/下载：1192/149 \| 提交时间：2009/09/18 AUTLER-TOWNES MICROSCOPY QUANTUM INTERFERENCE POSITION MEASUREMENT HETERODYNE MEASUREMENT NONLINEAR OPTICS 4-LEVEL SYSTEM MOVING ATOMS SINGLE-ATOM FIELD TRANSPARENCY
	Quantum interference effects of two coherent population trapping states on the atomic spectral lines of a F-e=0 -> F-g=1 transition 期刊论文 OAI收割 j. phys. b-at. mol. opt. phys., 2005, 卷号: 38, 期号: 11, 页码: 1719, 1726 Hu ZF; Wang Y; Du CG; Wang YZ 收藏 \| 浏览/下载：1151/169 \| 提交时间：2009/09/18 DARK RESONANCES 4-LEVEL SYSTEM TRANSPARENCY VELOCITY LIGHT
	Nonlinear effects of third-and fifth-order on polarization beats in a four-level system 期刊论文 OAI收割 CHINESE PHYSICS, 2000, 卷号: 9, 期号: 8, 页码: 606 Zhang, YP; Lu, KQ; Wu, HC; Xu, J; Fu, PM 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/09/24 ULTRAFAST MODULATION SPECTROSCOPY PHASE-CONJUGATION GEOMETRY 4-LEVEL SYSTEM SUSCEPTIBILITY 3RD-ORDER GLASSES