推导了两种常用等步长相移算法的调制度表达式,提出一种新的调制度分析方法。该方法用于等步长相移法中基于加权最小二乘法的相位展开,能够充分利用调制度信息,构造二值和小数权重,从而增强相位展开过程对多种干扰因素的免疫力。实验结果说明了该方法的有效性和实用性。最后比较了二值权重和小数权重在加权最小二乘法的相位展开中的性能表现。

A new method of analysis of intensity modulation is proposed for phase unwrapping of equal-step phase-shifting interferometry. By analyzing the intensity modulation of interference speckle patterns, a variety of noise, inconsistence and invalid data area can be identified. A binary and decimal weight can be constructed by this method for weighted phase unwrapping that utilizes least-squares approach and enhances the immunity of phase unwrapping from kinds of disturbing factor. The application of this method to Carré algorithm and Stoilov algorithm is discussed. The experimental result shows the validity and praticality of this method. A comparison of the performance of binary and decimal weight in weighted least-squares phase unwrapping is provided.