Modeling and analysis of space-rotation error induced by phase-shifter in phase shifting interferometry

Based on the mathematical model that describes the end-rotation of piezoelectric actuator as phase-shifter, the space-rotation error is analyzed in theory. According to the model, phase-shifters of two different processing ways are tested on Twyman-Green interference system, respectively. By processing the fringe rotation and interval changes, the phase-shifter end rotation and its space-rotation error can be analysed. With this method, the detecting sensitivity for spatial displacement induced by phase-shifter end rotation reaches picometer order; under the driving voltage from 0 V to 100 V, the micro-displacement measurement precision in the phase shifting direction is better than λ/200, corresponding to the phase-shifting precision better than 0.06 rad.