Electronic speckle pattern interferometry based on spatial fringe analysis method
Electronic speckle pattern interferometry based on spatial fringe analysis method
复制标题
基于空间条纹分析方法的电子散斑干涉测量
DOI：
10.1117/12.445547
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
S. Yokozeki
中科院分区：
文献类型：
--
作者：
Y. Arai;S. Yokozeki
通过讨论散斑图信号在傅里叶域上的空间频率分布，结合实验和计算机模拟结果，研究了散斑大小对测量精度的影响。研究发现，条纹图像的噪声元和信号元在空间频率域的分布位置关系与测量精度有关。从这些讨论中，我们可以得出如下结论：当散斑尺寸大于CCD的像素尺寸时，散斑图中的噪声元素增加，从而降低了测量精度。另一方面，在散斑尺寸小于像素尺寸的情况下，CCD的单个像素中存在许多散斑。因此，由于CCD的每个像素的输出与一个像素中的每个散斑的强度被平均，散斑强度的这种平均效应将导致测量精度的降低。结果表明，当散斑尺寸与CCD像素尺寸相同时，该方法的测量精度最大。
The influence of the speckle size to the measurement accuracy is investigated by discussing the spatial frequency distribution of the signal of specklegrams on the Fourier domain with the results of experiments and computer simulations. It is found out that the relationship of the location between the distribution of noise element and of signal element of fringe images in the spatial frequency domain is related to the measurement accuracy. From these discussions, we would conclude as follows: the measurement accuracy is decreased, because the noise element in the specklegram increases when the speckle size is bigger than the size of the pixel of the CCD. On the other hand, there are many speckles in single pixel of the CCD in the case that the speckle size is smaller than the size of the pixel. Consequently, because the output of each pixel of the CCD is averaged with the intensity of each speckle in one pixel, this averaging effect of the intensities of speckles would bring the decrease of the measuring accuracy. The results show that the measurement accuracy of this method is maximized in the case that the speckle size is as large as the pixel size of the CCD.