High-accuracy and high-efficiency calibration method for determining voltage-phase characteristics of LCVR based on a Wollaston prism

Abstract

Liquid crystal variable retarder (LCVR), as a promising and precision device in applications of light field modulations and manipulations, has been widely used to change the phase and thus the polarization state of light based on electronically controlled rotations of liquid crystal molecules. However, the LCVR usage inevitably involves an important task, i.e., the calibration, since the phase retardation of LCVR changes with the temperature of the environment and the wavelength of the incident light. In this paper, based on using a Wollaston prism, we propose an effective calibration method to tailor the voltage-phase characteristic curves of LCVR. In the experiment, given a wavelength of light to be calibrated, similar calibration results are always obtained, regardless of the angle of polarization (AoP) of the incident light and the angle of LCVR placement. Experimental results show that the root-mean-square error (RMSE) of the voltage-phase calibration is no more than 0.132 radian. Moreover, excellent robustness and efficiency of this LCVR calibration method are also demonstrated and verified.