Topographic Imaging by Wavelet Correlation Method

小波相关法地形成像

• 批准号: 07650042
• 负责人: ITOH Masahide
• 金额: $ 1.73万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07650042/
• 关键词: Wavelet Correlation; dettect measurement; Whitetight interterometer; Scatter light; non-contact measurement

In the interferometry using incoherent light source, the interference fringes are generated only at the part of zero optical path difference between two arms of interferometer. Generally, because the indefiniteness of the wavelengths exists in the coherent interferometric measurement, the position of the isolated point is not able to be determined. The absolute position of the scattered seed can be measured from the position of the reference mirror where the interference fringes is generated by the sample and the mobile reference mirror. The interference method by such a low coherence light source is called as a wavefront correlation method.In this study, we made Twyman-Green type interference meter. To improve more precision, it is examined about the phase shift method, that is commonly used in coherent interferometry. We analyzed about the points when applying the method to the interference method which used incoherent light source.As the application of this study, we measured an absolute height of the block gage in the order of the few cm. The data is compared with the result of fractional technique using the numerous wavelength light source, and we evaluated an error. In case of living sample, because of the small S/N ratio of the interference fringes, we analyze the technique of wavelet conversion, sepstrum conversion and/or correlation method We also examined the possibility to use a semiconductor laser as the brighter light source. We performed to move about 50nm wavelength in the system of Littoman arrangement. Using this light source, more accurate measurement may be realized by scanning the wavelength in real-time.

在使用非相干光源的干涉测量中，干涉条纹仅在干涉仪两臂之间的零光程差部分产生。通常，相干干涉测量由于存在波长的不确定性，无法确定孤立点的位置。散射种子的绝对位置可以从参考镜的位置测量，其中样品和移动参考镜产生干涉条纹。这种低相干光源的干涉方法称为波前相关法。在本研究中，我们制作了Twyman-Green型干涉仪。为了提高精度，对相干干涉测量中常用的相移法进行了研究。我们分析了将该方法应用于使用非相干光源的干涉方法时的要点。作为本研究的应用，我们测量了几厘米量级的块规的绝对高度。将数据与使用多种波长光源的分数技术的结果进行比较，并评估误差。在活体样本的情况下，由于干涉条纹的信噪比较小，我们分析了小波转换、七谱转换和/或相关方法的技术。我们还研究了使用半导体激光器作为更亮光源的可能性。我们在Littoman排列的系统中进行了约50nm波长的移动。利用该光源，通过实时扫描波长可以实现更精确的测量。

项目成果

M.Itoh et al: "Broad-band light-wave correlation topography using wavelef-transform" Optical Review. 2. 135-138 (1995)

M.Itoh 等人：“使用小波变换的宽带光波相关地形”光学评论。

N. Yoshikawa, et al: "Interporation of reunstructed image in houriet Transtern" Opt. Commun.119. 33-40 (1995)

N. Yoshikawa 等人：“在houriet Transtern 中重构图像的插入”Opt。

H.Huany et al: "Optial module for modified signed-digit computing pased encoding and pattern recognition" Optial Review. 2. 255-258 (1995)

H.Huany 等人：“用于修改符号数字计算的编码和模式识别的光学模块”光学评论。

H. Huang, et al.: "Optical module for modifiedsigned-digit compatingbased encordiug and pattern recognition" Opt. Rev.2. 255 (1995)

H. Huang 等人：“基于修改符号数字计算的编码和模式识别的光学模块”

M.Itoh et al: "Broad-band light-wave correlation topography using wavelet transform" Optical Review. Vol.2. 135-138 (1995)

M.Itoh 等人：“使用小波变换的宽带光波相关地形”光学评论。