Improved Phase Unwrapping of Shift Interferometer Using Precision XY-scanner

Abstract

A phase shift interferometer with an improved phase unwrapping is presented. The nanometer resolution XY stage is integrated into the standard temporal phase shifting interferometer. The nanometer resolution XY stage is used to position specimen in subpixel of CCD detector, therefore CCD detectors sampling frequency is made high. This paper presents spatial sampling of CCD and two scanning algorithms, whose simulation and experiment results are also presented. The results show that the scanning algorithms make CCD detector's sampling frequency high, and phase unwrapping is improved also.