<title>Analysis of oblique fringes by fringe pattern matching</title>

Abstract

This paper presents a method for determining the slope and period of oblique and equi-spaced fringes by fringe pattern matching. In the method, two pairs of image patches in two different regions of a fringe pattern are selected for fringe pattern matching, and the phase shift between the fringes in the two selected regions of the fringe pattern is obtained from the two mismatch curves which are calculated from the mismatch function in fringe pattern matching. The slope and period of oblique fringes can be therefore determined using the distance between the two selected regions, the phase shift between the fringes in the regions, and the period of mismatch function with a subpixel resolution. The effect of image patch size on the determination of the slope and period of oblique fringes is also discussed based on a statistical analysis. The statistical analysis, computer simulation and experimentation results have shown that the determination of the slope of oblique and equi-spaced fringes by fringe pattern matching has the advantage of averaging noise due to the region-based matching.