一种解调阴影叠栅条纹的新方法

THE FREQUENCY SHIFTING TECHNOLOGYTHE FREQUENCY SHIFTING TECHNOLOGY IN SHADE MORIE FRINGE

本文提出了一种叠栅条纹解调技术，我们称它为频移叠栅法，它不同于相移叠栅法，前者改变了叠栅条纹分布的频率，后者只是改变了叠栅条纹的相位．本文从阴影叠栅图分布的基本公式出发，借助于相移阴影叠栅法的思想推导并得出了频移阴影叠栅法的公式，在此基础上给出了特定条件下的实用公式．同时也分析了其相位图，将其主值范围从0～π拓展到0～2π，解决了其去包裹中正负号确定问题．最后给出了实验结果，并分析和模拟了由于频移的不准确给测量结果带来的影响．

A new method is presented to extract quantitative information of Moire fringes. It is different from the method of phase shift. Instead of changing the phase of Moire fringe,it changes the frequency of the Moire fringe. The theoretical formula is introduced for a special relationship of three frequency. For unwrapping the phase image, the first step is to expend the cosine value range from (0,π) to (0, 2π)to avoid the problem, of decide'plus'or'minus'. The experiment result is given and theeffect of the error of relationship of the position of light source on measuring results are also discussed.