提出一种基于小波匹配滤波和傅里叶变换技术的干涉图条纹数/条纹间距的提取方法。该方法是先对粒子场干涉条纹图和粒子掩模图像，利用Mexican Hat小波分别提取其边缘图像，对所得到的边缘图像进行2D相关运算得到粒子的中心位置。根据粒子的中心坐标及粒子图像形状大小提取出单个粒子干涉图像。再对每个粒子干涉图像进行傅里叶变换，利用修正Rife方法提取条纹频率，得到粒子干涉条纹数/条纹间距，其测量精度可达到亚像素精度，并进行了模拟和实验测量。当重叠系数γ<11.62%时，算法识别率高于90%，频率提取误差小于0.0185%。对51.1 μm的标准粒子测量的不确定性为±0.41 μm，绝对误差1.31 μm。研究结果表明了该算法的可行性。

A method of extracting the number of fringes/fringe spacing of interferogram based on wavelet matched filtering and Fourier transform technique is proposed. The edge images of the interference pattern of particle and the particle mask image are detected respectively by Mexican Hat wavelet and the center of particle can be extracted through the 2D correlation operation for the two edge images obtained. Then the interference pattern of each particle can be achieved using the center coordinate, shape and size of the particle image. The fringe counting/fringe spacing of the interferogram of a particle is obtained by Fourier transform and the modified Rife algorithm, and sub-pixel accuracy of the extracted frequency is acquired. The performance of the method is demonstrated using simulation and experimental measurements. The simulation results are that the recognition ratio is more than 90% and the extracted frequency error is less than 0.0185% for the overlap coefficient γ<11.62%. The measurement uncertainty is ±0.41 μm and the absolute error is 1.31 μm for the standard particles of diameter of 51.1 μm. The research results show that the algorithm presented in this paper is feasible.