光学仪器, 2018, 40 (1): 1, 网络出版: 2018-04-09
基于傅里叶变换的数字散斑照相测量
Displacement measurement of digital speckle photography based on Fourier transform
摘要
提出了基于傅里叶变换的双曝光散斑场的全场数字化测量。对双曝光散斑图进行傅里叶变换得到条纹图以灰度归一法和相位构造法将其优化,获取低噪声、高对比度的散斑干涉条纹。平面位移的测量实验结果表明,数字散斑照相技术适合计算机进行自动条纹识别和位移场计算,能得到较为精确的水平位移值,可实现变形场的精准测量。
Abstract
A whole-field digital measurement based on Fourier transform is proposed to realize double exposure speckle field.The bar chart received from double exposure specklegram through Fourier transform is optimized by grayscale normalization and phase construction to get a speckle interference fringe with low noise and high contrast.The experimental result of measuring plane displacement shows that digital speckle photography is suitable for automatic stripe identification and calculation of displacement field by computer to get accurate results of plane displacement,which can achieve the precise measurement of the deformation field.
曾媛, 钱晓晨, 顾页妮, 韩朝霞, 陶春先. 基于傅里叶变换的数字散斑照相测量[J]. 光学仪器, 2018, 40(1): 1. ZENG Yuan, QIAN Xiaochen, GU Yeni, HAN Zhaoxia, TAO Chunxian. Displacement measurement of digital speckle photography based on Fourier transform[J]. Optical Instruments, 2018, 40(1): 1.