Simultaneous polarization Mirau interferometer based on pixelated polarization camera

We propose a polarization Mirau interferometer using the pixelated polarization camera to acquire the four phase-shifted interferograms simultaneously by which motionless phase shift can be realized. A wire-grid polarizer is employed as the polarization beam splitter to realize the adjustable fringe contrast. Due to the limited contrast ratio of split orthogonally polarized beams with a wire grid polarizer, the corresponding calibration method by superposition of exchanged transmitted and reflected beams is proposed to obtain the uniform fringe contrast in four phase-shifted interferograms. The accuracy of the proposed system is demonstrated experimentally, and a precision better than 1/500 wavelength is achieved. The proposed system provides a feasible way to obtain the instantaneous measurement with minimizing environmental disturbance.