Adaptive asynchronous algorithm for fringe pattern demodulation

Abstract

We present a spatial adaptive asynchronous algorithm for fringe pattern demodulation. The proposed algorithm is based on the standard five-step asynchronous method with the one modification that we select the best sample spacing for each point of the fringe pattern. As we show, the frequency response of any asynchronous method depends on the sample spacing. This interesting behavior is used to select the best sample spacing as the one that gives the biggest response for each location. The overall result is a spatial demodulation algorithm with an improved frequency response compared to the existing ones. We show the feasibility of the proposed method with theoretical analysis as well as experimental results.