中国科学院机构知识库网格系统: 检索

浏览/检索结果: 共3条，第1-3条

帮助

条数/页：排序方式：
	Improved method of target detection on optoelectronic hybrid joint transform correlator in cluttered scences (EI CONFERENCE) 会议论文 OAI收割 2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China 作者: Yang L.; Yang L. 收藏 \| 浏览/下载：38/0 \| 提交时间：2013/03/25 A classical joint transform correlator (JTC) usually yields large correlation sidelobes as well as a large correlation peak width strong zero-order peak and low diffraction efficiency which make the detection ability of JTC lower. To overcome these difficulties firstly a joint power spectrum (JPS) subtraction technique in Fourier plane was proposed where reference image power spectrum and object image power spectrum are subtracted from the JPS before inverse Fourier-transform operation it is obvious that the modified JPS removes the zero-order term. Secondly a fringe-adjusted filter (FAF) was presented to suppress sidelobes and noises. The modified JPS is multiplied by a FAF before the inverse Fourier-transform operation to obtain the cross-correlation peak. Computer simulations demonstrated the improved method can obviously remove zero-order diffraction and effectively suppress the sidelobes and noises compared with classic JTC and then improve the detection ability for JTC. Experimental results presented the sharp correlation peak and also confirmed the method effectiveness. (2012) Trans Tech Publications Switzerland.
	Study on the fabrication of blazed grating with sub-micrometer space on aluminum film (EI CONFERENCE) 会议论文 OAI收割 12th International Manufacturing Conference in China, IMCC2006, September 21, 2006 - September 23, 2006, Xi'an, China Lun S.; Hao D.; Qi X. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 The saw tooth grooves of blazed grating ruled by ruling engine are formed by diamond tool which presses on the aluminum film evaporated on the substrate of optical glass or metal. The real shape of ruled saw tooth groove is different from that of the ideal groove and the ruling process indicates that there are the zero order planes similar to the flat tops on the grating grooves. The results of Fourier analysis for the real ruled grating featuring the zero order plane structure shows that the flat top width is an important factor for grating efficiency. Additionally bigger pressure value loaded on the diamond tool and bigger lateral pressure value on the aluminum film will be benefit to the improvement of grating diffraction efficiency. Based on the grating interferometer the high precision positioning control system of ruling engine guarantees the accuracy of the grooves space. High density blazed grating whose space is 0.83p.m is manufactured and its' grooves spaces are very equidistant and uniform under the view field of AFM. And the infrared blazed grating whose diffraction efficiency in the first order is up to 97 percent is ruled successfully also.
	Elimination of zero-order diffraction in digital holography 期刊论文 OAI收割 opt. eng., 2002, 卷号: 41, 期号: 10, 页码: 2434, 2437 Liu C; Li YZ; Cheng XT; Liu ZG; Bo F; 朱健强收藏 \| 浏览/下载：1487/293 \| 提交时间：2009/09/18 digital holography zero-order diffraction Laplacian