Phase gradients from intensity gradients: a method of spatial carrier fringe pattern analysis.

In optical measurement, spatial carrier fringe pattern analysis is suitable for measuring dynamic events in real-time. This paper presents a novel technique for analyzing a spatial carrier fringe pattern. It estimates the local phase gradients at a pixel from its neighborhood, by use of statistics of the intensity gradients. Using the estimated phase gradients, the phase map of the fringe pattern is recovered by solving numerical partial derivative equations or using an adaptive spatial carrier phase shifting (SCPS) algorithm. Simulation and experimental results demonstrate this algorithm to be valid.