Algorithm for directly retrieving the phase difference: a generalization

Determination of phase difference is important in many applications of optical metrology. Algorithms for temporal phase difference measurement using the Fourier transform and phase shifting methods are available. These algorithms are first shown to be equivalent and then are generalized for spatial phase difference measurements and a spatial carrier phase shifting method. The efficiency of the algorithm is verified by two examples for slope and curvature determination. 2003 Society or Photo-Optical Instrumentation Engineers.