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浏览/检索结果: 共8条，第1-8条 帮助 限定条件 专题：长春光学精密机械与物理研究所    第一署名单位    第一作者单位    通讯作者单位     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 The state of the art for liquid crystal adaptive optics in astronomical applications (EI CONFERENCE) 会议论文 2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China Hu L.; Xuan L.; Cao Z.; Mu Q.; Peng Z.; Liu Y.; Yao L.; Yang C.; Lu X.; Xia D. L. M. 收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25 In this paper  we summarize the researches of liquid crystal (LC) adaptive optics(AO) in astronomical applications. Dual frequency and nematic LC materials were reported to be used in astronomical observations. However  nematic LC with its simple producing and driving method and multi-gray-level is promising in the application. We have investigated the nematic LC AO system and promoted its application for nearly ten years. Here  we reported our newest nematic LC AO system with bandwidth result of 3dB is 54.4 Hz  0dB bandwidth is 79.1Hz. 2012 IEEE.   A brightness and color correction method of LED display based on CCD camera (EI CONFERENCE) 会议论文 2012 International Applied Mechanics, MechatronicsAutomation and System Simulation Meeting, AMMASS 2012, June 24, 2012 - June 26, 2012, Hangzhou, China Zhao Z.; Wang R. 收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25 The correction methods of LED displays are aiming to address the uniform issues which includes brightness aspect and color aspect. The correction method use a 33 correction coefficients matrix to reshape the pulse width of each LED. To calculate the correction coefficients  a linear system is established  which includes a color CCD and a LED display. And a correction algorithm is introduced based on the color CCD. This algorithm describes the relationships of the main color components of a LED  when the gray level of a LED is increasing or decreasing  the three main color components would change according to the correction coefficients. The results shows that the correction based on this algorithm improved the performance of LED displays. (2012) Trans Tech Publications  Switzerland.   Study on sub-pixel techniques for accurate image measurement of displacement (EI CONFERENCE) 会议论文 2011 2nd International Conference on Advanced Measurement and Test, AMT 2011, June 24, 2011 - June 26, 2011, Nanchang, China Xie Z.; Zhang X. 收藏  |  浏览/下载：12/0  |  提交时间：2013/03/25 The high resolving power camera was often used to improve the precision of measuring system although its price is high  because the accuracy of image measure was limited by the pixel resolving ability of camera. A method of one dimension gray level quadrature sub-pixel to detect edge was presented. This method was applied to measure the displacement of measuring head on 3-coordinate measuring machine. The data of test was shown that this system can distinguish displacement 0.001mm. it is higher accuracy than pixel level. So this method is convenient and fast  fit to track and measure the moving object. It is obvious that this method can save the cost of hardware.   Sort optimization algorithm of median filtering based on FPGA (EI CONFERENCE) 会议论文 2010 International Conference on Machine Vision and Human-Machine Interface, MVHI 2010, April 24, 2010 - April 25, 2010, Kaifeng, China Lu Y.; Jiang L.; Dai M.; Li S. 收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25 The traditional sorting algorithm of median filtering is optimized according to the hardware structure features of FPGA. FPGA is used to acquire the data parallelly for comparing the data of the same column in the median filtering window. Comparing results shared by adjacent filter window are saved temporarily to match the new round of median filtering by using FPGA internal resources. This method can reduce the comparing times from current 21 down to 13  and improve the algorithm efficiency nearly 40%.The experimental results prove that the optimized algorithm can filter a 1K1K gray-level image in about 20ms  which ensure the proposed algorithm can be applied in the real-time image median filtering system. 2010 IEEE.   The registration of aerial infrared and visible images (EI CONFERENCE) 会议论文 2010 International Conference on Educational and Information Technology, ICEIT 2010, September 17, 2010 - September 19, 2010, Chongqing, China Sun M.; Bao Z.; Liu J.; Wang Y.; Quan Y. 收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25 In order to solve the registration problem of different source image existed on aerial image fusion  algorithms based on Particle Swarm Optimization (PSO) are applied as search strategy in this paper  and Alignment Metric (AM) is used as judgment. This study has realized the different source image registration of infrared and visible light with high speed  high accuracy and high reliability. Basically  with little restriction of gray level properties  a new alignment measure is applied  which can efficiently measure the image registration extent and tolerate noise well. Even more  the intelligent optimization algorithm - Particle Swarm Optimization (PSO) is combined to improve the registration precision and rate of infrared and visible light. Experimental results indicate that  the study attains the registration accuracy of pixel level  and every registration time is cut down over 40 percent compared to traditional method. The match algorithm based on AM  solves the registration problem that greater differences between different source images are existed on gray and characteristic. At the same time  the adoption of combining the intelligent optimization algorithms significantly improves the searching efficiency and convergence speed of the algorithms  and the registration result has higher accuracy and stability  which builds up solid foundation for different source image fusion. The method in this paper has a magnificent effect  and is easy for application and very suitable for engineering use. 2010 IEEE.   Gray level correction algorithm of LED display panel based on least squares approximation (EI CONFERENCE) 会议论文 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Sun Z.-Y.; Chang F.; Wang R.-G.; Zheng X.-F. 收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25 Aiming at the problem that the linear characteristic of LED display panel is not compatible with the non-linear characteristic of image data  this leads to appear the large deviation during grayscale rendition  the gray level correction algorithm based on least squares approximation is provided. First  the necessity of gray level correction is analyzed. Then  the gray level correction algorithm model is constructed according to the principle of latest squares approximation. Next  realization steps are described in accordance with this constructed algorithm model. Finally  this algorithm is implemented in a LED display panel  whose resolution is 128128. Experimental results show that this algorithm is able to reduce the deviation obviously during grayscale rendition and the problem of gray level deformation can be resolved perfectly because the linear relation between image data after correcting and gray level is good which satisfies the linear characteristic of LED display panel. 2010 IEEE.   The deviation of color matching algorithm in the field of full-color LED display (EI CONFERENCE) 会议论文 2009 2nd International Congress on Image and Signal Processing, CISP'09, October 17, 2009 - October 19, 2009, Tianjin, China Hao Y.-R.; Wang Y.; Zhang X.; Wang R.-G.; Chen Y.; Ding T.-F. 收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25 In this paper  a color gamut transformation method which transformed the different color gamut into a same one has been proposed. In the transforming process  the deviation which was arose from the quantization error and the truncation error were existing. If the deviation was out of the color tolerance  the uniformity of the screen color will be deteriorated. Firstly  the color tolerance of vision was calculated by the color-difference formula. Secondly  in the full-color LED display experiments  it was analyzed that the tri -color tolerance values are respectively 2.5  2.8 and 1.3. According to the tri -color tolerance values and the color difference formula  the express of the quantization precision  gray value and the color difference was set up. Finally the gray-scale range of the color uniformity was analyzed by the collected data  it was concluded that the uniformity of the display was satisfied the requirement of the visual when the range of the gray level was [11  14]  and when the range was [1  11]  the value of the color difference was also reduced significantly. 2009 IEEE.   High-accuracy real-time automatic thresholding for centroid tracker (EI CONFERENCE) 会议论文 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China Zhang Y.; Wang Y. 收藏  |  浏览/下载：26/0  |  提交时间：2013/03/25 Many of the video image trackers today use the centroid as the tracking point. In engineering  we can get several key pairs of peaks which can include the target and the background around it and use the method of Otsu to get intensity thresholds from them. According to the thresholds  it give a great help for us to get a glancing size  a target's centroid is computed from a binary image to reduce the processing time. Hence thresholding of gray level image to binary image is a decisive step in centroid tracking. How to choose the feat thresholds in clutter is still an intractability problem unsolved today. This paper introduces a high-accuracy real-time automatic thresholding method for centroid tracker. It works well for variety types of target tracking in clutter. The core of this method is to get the entire information contained in the histogram  we can gain the binary image and get the centroid from it. To track the target  so that we can compare the size of the object in the current frame with the former. If the change is little  such as the number of the peaks  the paper also suggests subjoining an eyeshot-window  we consider the object has been tracked well. Otherwise  their height  just like our eyes focus on a target  if the change is bigger than usual  position and other properties in the histogram. Combine with this histogram analysis  we will not miss it unless it is out of our eyeshot  we should analyze the inflection in the histogram to find out what happened to the object. In general  the impression will help us to extract the target in clutter and track it and we will wait its emergence since it has been covered. To obtain the impression  what we have to do is turning the analysis into codes for the tracker to determine a feat threshold. The paper will show the steps in detail. The paper also discusses the hardware architecture which can meet the speed requirement.  the paper offers a idea comes from the method of Snakes