Method for recovering phase distribution of phase shift interference figures and method for obtaining phase shift between two figures

Abstract

The invention discloses a method for recovering phase distribution of phase shift interference figures and a method for obtaining phase shift between the two figures. The method for obtaining the phase shift between the two figures comprises writing each interference figure in the form of a matrix and serving each interference figure as a column vector matrix; obtaining a background component through a low-pass filter; subtracting each column vector formed by the corresponding phase shift interference figure from the background component to obtain a pair of vectors and forming a subspace by the two vectors to achieve the vectorization of the interference figures, wherein an included angle is formed between the vectors; obtaining an orthogonal basis of the subspace through a basis in the subspace by a Schmidt orthogonalization method, further obtaining a corresponding standard orthogonal basis and obtaining an included angle formed between two original signals through the obtained standard orthogonal basis. According to the method for recovering the phase distribution of the phase shift interference figures and obtaining the phase shift between every two figures, the phase distribution between the two phase shift interference figures can be obtained and the changes of the phase shift can be further obtained through the series of phase shift interference figures.

Description

technical field [0001] The invention relates to the field of optical imaging, in particular to a method for obtaining the phase shift between two images based on the Schmidt quadrature method, and a method for restoring the phase distribution of the phase-shifted interferogram. Background technique [0002] In recent years, recovering the distribution of the phase to be measured from the interferogram of unknown phase shift is a hot spot in the research of phase recovery methods, mainly including Fourier transform method and iterative method based on least squares principle, arccosine method, principal component analysis methods, etc. [0003] Among them, the phase to be measured is recovered based on the Fourier transform method, which is to separate the real part and the imaginary part of the -1-order spectrum of the interferogram in the frequency domain by performing a spatial Fourier transform on a single interferogram. The cut function calculates the phase distribution...

AI Technical Summary

Problems solved by technology

[0010] The purpose of the present invention is to provide a method for recovering the phase distribution of a phase-shifted interferogram and obtaining the phase shift between two pictures, aiming at solving the existing method of recovering the phase distribution to be measured from an interferogram with an unknown phase shift Sensitivity to noise, large amount of calculation, or requiring at least one fringe change in the interferogram

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