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A theoretical method based on Fourier spectrum analysis for the focusing performances of the X-ray compound refractive lenses 总被引:1,自引:0,他引:1
It is important to predict the intensity distribution in focusing plane for designing the X-ray compound refractive lenses. On the basis of analyzing the structure of X-ray compound lenses and comparing it with Praunhofer diffraction system, it is concluded that the X-ray focusing system can be regarded as a kind of Praunhofer diffraction system. Therefore, a method based on Fourier spectrum analysis is presented to predict the intensity distribution in the focusing plane for the X-ray lenses. A brief analysis on the relationship between the parameters of X-ray lenses and their focusing performance is also given in this paper. 相似文献
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介绍了一种实时MPEG-2以太网传输系统的设计方案,它由硬件MPEG-2编/解码卡和基于ARM处理器的嵌入式系统卡构成,前者用于视音频的实时压缩编码和解码,后者将MPEG-2数据流进行IP封装和解封装,还分析了IP网络传输对接收端MPEG-2解码视音频的影响,并设计了一些测评方法对系统进行了相关测评. 相似文献
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Organic electroluminescent (EL) devices were firstly demonstrated in the 1960s, but great interest was not shown until 1987 that Tang and Vanslyke succeeded in developing an effective device using tris(8-hydroxyquin oline) aluminum (Alq3) as the emitter[1-4]. Since then, different kinds of organic dyes, chelate metal com- plex and polymers were synthesized to fabricate higher efficiency devices. Polymers containing rare earth have been used to fabricate the full-color devices because the ver… 相似文献
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声光可调滤波器(AOTF)是未来全光网络中实现波长路由选择的首选器件,为制作该器件必须首先完成驱动模块射频电路的设计.文章介绍了一种声光可调谐滤波器驱动系统的实现,该系统基于ARM7控制的用于中心波长为1500的波分复用光网络;基于频率合成芯片ADF4360-8以及ATMEL公司的AMR7芯片AT91SAM7S256.利用仿真软件ADIsimPLL配合设计芯片外围电路.以这种方式设计的射频电路覆盖了1500~1600 nm的光谱范围,能实现lnm的波长调谐,具有结构简单、操作方便、稳定性高等特点. 相似文献
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