Errors in two-directional spatial-carrier phase shifting method for closed fringe patterns analysis

摘要

Two-directional method was proposed for analysis of crossed or closed fringe patterns. This paper focuses on the analysis of closed fringe pattern and the major limitations for the N-point algorithms (standard five-point, modified five- and three-point algorithms). The limitations include the influence of the tilt of fringes, variations in the background intensity and contrast functions, the nonlinearities in a detection system, random noise. Computer simulation reveal the character and the magnitude of the major errors for all algorithms tested. The comparison of the results obtained is given and the advantages of using the modified five- and three-point algorithm are described.