Study on the Birefringence Measurement Method by Using a Liquid Crystal Phase Shifter

Abstract

Since the anisotropy of the refractive index can be controlled by a low voltage and low electric power, the liquid crystal is extremely useful as a high-speed phase shifter that doesn't need any mechanical operation. In our study, we examined the phase shift interferometry system which can measure the 2-dimensional birefringence distribution by building the OCB liquid crystal cell, that is expected to be a high-speed response, into the polarizing microscope. As a result, it is found that the measurement precision of the phase difference about 10 nm is obtained by using the phase-shifting interferometry with four step algorithm.