Calibration of phase liquid crystal spatial light modulators using high-order Taiji radial-shearing interferometry

Abstract

The modulation characteristics of liquid crystal spatial light modulators (LC-SLMs) are related to the incident wavelength. In order to load the grayscale image correctly, LC-SLMs must be calibrated before using. We propose high-order Chinese Taiji radial-shearing interferometry to calibrate the phase modulation curve of an LC-SLM, which is different from the conventional calibration method. The new method is proposed to establish the mapping relationship between LC-SLM grayscale and phase modulation by rotating multiple Airy spots, which are derived from radial-shearing interference through a high-order Chinese Taiji lens. Compared with the traditional interference fringes, one of the greatest advantages is that the function between the grayscale and rotation angle of the two Airy spots is established more easily. Moreover, it eliminates the complex data processing steps and has a high enough signal-to-noise ratio. The experimental results show that high-order Chinese Taiji radial-shearing interferometry is a very effective calibration method for LC-SLM.