Phase demodulation from a spatial carrier fringe pattern by spatial-temporal fringes method

Abstract

Phase extraction from a single fringe pattern is a valuable but challenging task. In this paper, a spatial carrier phase-shifting algorithm based on spatial-temporal fringes method is proposed to demodulate the phase from a single carrier interfergram. Firstly, two phase-shifted fringe patterns are composed from the original interferogram shifting by several pixels their starting position. Secondly, these two phase shift fringes are fused into one spatial-temporal fringes (STF) image. Then, the modulating phase is calculated from the frequency spectrum of the STF image. Meanwhile, the main factors, such as the level of random noise, the carrier frequency values and angle of fringe pattern are analyzed and discussed in the simulations, and experimental results are given to demonstrate the validity of the proposed method. The proposed method is effective, accurate and immune to external disturbance and vibration, which greatly promotes the application in the on-line detection fields.