基于三角形收缩法改进的分数傅里叶变换估计牛顿环参数

; Aiming at a slower rate when the fractional Fourier transform is used for the estimation of Newton rings parameters, the method based on the triangle shrinkage of the improved fractional Fourier transform is proposed by analyzing the distribution law of the maximum value of the amplitude in the fractional domain of the Newton rings fringe images and the corresponding angle ol rotation. The experimental results show that the method is feasible, and the processing time is less than Is for the fringe images with an image size less than 640 X 640 pixels. With the increase of the image size, the number of fringes contained in the fringe image increases, and the relative error of the estimated value of the radius of curvature decreases. The processing time is still able to meet the practical needs of engineering. When processing the image of 1080 X 1080 pixels, the relative error of the estimated value is 0. 001%, and the processing time is 3. 31 s. The method estimates the 720 X 720 pixels Gaussian noise-damaged Newton ring interferometrie fringe image in an average time of 1. 28 s, which is about 1/700 of the traditional fractional Fourier transform time.