Frequency-shifting method for phase retrieval from fringe patterns

Abstract

A novel frequency-shifting method for phase retrieval from fringe patterns is proposed. It needs two fringe patterns. In the second fringe pattern, a low frequency carrier is introduced. The low carrier frequency is used to open only fringe patches near critical points rather than the whole fringe pattern. The windowed Fourier ridges algorithm is used to retrieve the phase, which is able to characterize the density of the fringe patterns so that critical points can be recognized. The method is verified by a simulation example.