There are some kinds of troubles in the processing, for example, a phase unwrapping process, an accuracy of analysis, and so on, in the case that the spatial fringe analysis method based on the moire technique is applied to a noisy fringe image. In this paper, the digital filter technique and the filter based on the probability process are applied to the spatial fringe analysis method in order to solve these problems. In the simulation for the model of the fringe image, the results show that the spatial fringe analysis method using the digital filter is strongly robust against noise, and that the method with the Kalman filter can smoothly and accurately detect the phase map for the object with a continuous phase distribution. Furthermore, the method is applied to analyze a speckle fringe image from ESPI. The results show that spatial fringe analysis method based on the moire technique can analyze accurately the phase of a speckle fringe image with only single image. The proposed method can be anticipated as the technology which accelerates the use of the ESPI.
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