Calibration for phase-shifting polarizer array in the simultaneous phase-shifting interferometer

Simultaneous phase-shifting technology is used to capture several interferograms with certain phase intervals in different spacial positions at the same time. It can be applied to dynamic measurement because of its simultaneous interferograms-capturing characteristic. In order to guarantee the precision of the spacial phase-shifting, a method for calibrating the phase-shifting values of the polarizer array is proposed to fulfill the need. Based on the simultaneous phase-shifting interferometer, two methods by use of PZT and Soleil-Babinet compensator are utilized to obtain the phase differences of the neighbouring interferograms and the transmission direction differences of the corresponding polarizers. The experimental results indicate the average transmission direction error of the phase-shifting polarizer array is less than 1°, which can guarantee phase-shifting precision in the simultaneous phase-shifting interferometry.