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	Design of reimaging F/1.0 long-wavelength infrared optical system (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 A reimaging F/1.0 long-wavelength infrared optical system is proposed. The design has a flexible opto-mechanical layout. The design process is as follows. Firstly the catadioptric reimaging system consists of two reflecting mirrors and a relay lenses. Two reflecting mirrors make up of the first imaging system and are therefore free of chromatic aberrations while low dispersion lenses were used in the reimaging system so the optical system do not need achromatic design for a high image quality. Then to correct high-order aberrations resulting from large relative aperture more parameters need to be used with aspheric or diffractive surfaces due to modern optic technology development. Here aspheric is selected for easily manufacture. Finally the design is completed with the help of ZEMAX software. The effective focal length of the objective is 120mm and the field of view (FOV) is 4. The simulated final design shows adequate image quality and the modulation transfer function (MTF) is close to diffraction limit. The effect of the surrounding environmental temperature is analyzed using the concept of thermal defocusing and the thermal compensation is discussed. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	合成孔径激光成像雷达(Ⅲ):双向环路发射接收望远镜期刊论文 OAI收割光学学报, 2008, 卷号: 28, 期号: 7, 页码: 1405, 1410 刘立人收藏 \| 浏览/下载：1441/142 \| 提交时间：2009/09/18 合成孔径激光成像雷达 4-f system 望远镜 Defocusing 双向环路 Duplex circulator 4-f转像系统 Phase plate 离焦 Synthetic-aperture laser imaging radar 相位平板 Telescope
	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：33/0 \| 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.
	Energy transfer and red phosphorescence in strontium aluminates doped with Cr3+, Eu2+ and Dy3+ (EI CONFERENCE) 会议论文 OAI收割 Dielectrics in Emerging Technologies -and- Persistent Phosphors - International Symposia, May 15, 2005 - May 20, 2005, Quebec City, QC, Canada 作者: Wang X.; Wang X.; Wang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Cr3+ activated red (694 nm) long persistent phosphorescence originating from 2E-4A2 transition is observed in 4SrO·7Al2O3: Cr3+ Eu2+ Dy3+ system. It is demonstrated that the red phosphorescence is resulted from the conversion of Eu2+ activated blue phosphorescence through persistence energy transfer from Eu2+ to Cr3+. The excitation spectra of the 694 nm emission exhibit strong f-d band of Eu 2+ indicating the existence of the energy transfer. The dependence of lifetimes and intensities of the red and blue emissions on Cr3+ concentrations are studied. The intensity ratio of the red to blue emission bands obtained from photoluminescence spectra is in good agreement with that obtained from fluorescence lifetime measurements. The decay curves of the red phosphorescence at 694nm are also studied.
	Compound telescope (EI CONFERENCE) 会议论文 OAI收割 Novel Optical Systems Design and Optimization IX, August 15, 2006 - August 16, 2006, San Diego, CA, United states 作者: Liu H.; Liu H.; Sun Q.; Li F.; Liu H. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 Compound telescope is a new type of space optical system. It uses the concept of compound eyes and the property of diffractive lens. With the help of diffractive lens the diffractive optical system could become lighter weight lower cost and looser tolerance. And with the help of compound-eye configuration the field of view is expanded. A design example of compound diffractive optical system is given. It is composed of many diffractive telescope of F/4 200mm aperture 0.1 degrees field of view. It is shown that the whole system can approximately attain the diffraction limit over wide field of view.