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条纹中心法是干涉测量技术中分析单幅干涉图的一种重要处理方法,该方法主要包括图像预处理、波前重构和样品表面形貌及参数的测量等三个部分。研究了条纹中心法的关键技术,特别是应用协方差矩阵法求解泽尼克多项式以进行波前重构的过程。提出了基于单幅干涉图自动波前重构的流程方法。最后应用该流程方法处理由泰曼-格林干涉系统采集的精密抛光铝制盘基片表面形成的一幅干涉图像。实验结果表明,该方法可以实现单幅干涉图的自动波前重构,干涉波前重构的拟合精度可达1.4686×10^-6nm,还可以自动获得精密抛光铝制盘基片表面的形貌及参数。 相似文献
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迈克耳孙干涉仪中附加光程差对干涉图样影响的讨论 总被引:8,自引:1,他引:7
用迈克耳孙干涉仪做物理光学实验,教学中出现了在常规中不能出现的奇异现象,本通过分析仪器中的附加光程差,对干涉图样形成的原因作了定性解释,并得出结论。 相似文献
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High-precision technique for in-situ testing of the PZT scanner based on fringe analysis 总被引:2,自引:0,他引:2
A technique based on fringe analysis is presented for the in-situ testing of the PZT scanner, including the end rotation analysis and displacement measurement. With the interferograms acquired in the Twyman-Green interferometer, the testing can be carried out in real time. The end rotation of the PZT scanner and its spatial displacement deviation are analyzed by processing the fringe rotation and interval changes; displacement of the PZT scanner is determined by fringe shift according to the algorithm of template-matching, from which the relation between the driving voltage and displacement is measured to calibrate the nonlinearity of the PZT scanner. It is shown by computer simulation and experiments that the proposed technique for in-situ testing of the PZT scanner takes a short time, and achieves precise displacement measurement as well as the end rotation angle and displacement deviation measurement. The proposed method has high efficiency and precision, and is of great practicality for in-situ calibration of the PZT scanner. 相似文献
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分析了EAST装置偏振干涉仪系统进行电子密度测量时存在的密度跳变信号,开发了密度跳变信号修正程序.结果表明,通过该程序跳变的电子密度数据可以得到有效的修正. 相似文献
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Over the last 20 years, dichromated gelatin has been considered to be the best holographic recording material. However, the non-reproducibility of results in relation to light sensitivity, for a large number of experimental factors, restricted the use of this material. In this work, we consider the refractive index modulation profile and its stability. We propose a mixed method using Kogelnik's coupled wave theory (an approximate theory) and an alternative theory of diffraction in modulated media (an exact theory). The aim of this contribution is to use this mixed method in order to study the evolution of the modulation profile in correlation with the modification of the chemical environment during the final stage of processing. In our study we compare the effect of different kinds of final processing baths on the refractive index modulation profile. In order to characterize our holograms we have developed an experimental set-up for diffractive elements analysis. The experimental results are compared with the theoretical ones. For the numerical study we have carried out a complete set of numerical computations by using our own programs. These programs are based on a complete and exact solution of the Maxwell equations. 相似文献
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Research on identifying the order of fringe pattern traces using angular scan and zone search method
A method for automatically identifying the order of fringe pattern traces is presented. It uses the simplified Otsu algorithm for obtaining the threshold, the angular scan in the range of 45~ for searching the trace positions, and the zone search technique for identifying different traces. Experimental results show that the proposed method may reliably obtain the order of fringe pattern traces orientating from almost 45° to 90°. 相似文献
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受制造技术、磨损以及污染等因素影响,对线纹尺大批量自动化检定技术的实现存在较大困难。在线纹尺特征的基础上,针对边缘对比度高但噪声严重的线纹尺,先边缘初定位将图像处理区域限制在线纹边缘区域,再边缘精定位,寻找边缘区域灰度变化最大的点,剔除不连续的边缘点后拟合边缘线,实现线纹中心线的提取。针对自身变形导致成像模糊的线纹尺,背景区域与线纹区域分别求取各列灰度均值,再利用最小二乘拟合直线求交点实现线纹中心线提取。对高等别三等标准线纹米尺多次检定,结果表明,同一刻线最大差值为1.4μm,标准差为0.66μm,提出的算法鲁棒性好,满足高等别线纹尺的检定要求。 相似文献
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根据垂直扫描干涉技术结合样品折射率与密度间的依赖关系,建立了低密度SiO2泡沫微球密度的检测方法,用Lorentz-Lorenz和Gladstone-Dale公式分析了SiO2泡沫微球折射率与密度间的依赖关系。实验结果和测量误差估计表明,利用垂直扫描干涉技术并结合Gladstone-Dale分析方法,可实现对低密度SiO2泡沫微球密度的精密检测,其测量误差好于5%。 相似文献