Research on the deflection characteristics of non-mechanical beams of liquid crystal phase retardation cascade polarization gratings

According to the research status of fast beam pointing and scanning in space laser communication, this paper verifies the cascade of liquid crystal tunable phase retarder and polarization grating, and realizes the fast scanning and pointing of the beam according to the polarization and diffraction characteristics of light, and analyzes the relationship between voltage and delay,the voltage regulation accuracy is 0.001V, and verifies whether the spot intensity can be used in space laser communication, and realizes the fast pointing of four spots of ±6° and ±2°. The pointing accuracy is 30.49μrad, the beam divergence angle is about 0.0169°, connected to the diffraction grating, and the wavelength tuning of 1525nm-1600nm realizes 4.062° scanning of a single beam, 16.06° scanning in one dimension, and the wavelength tuning accuracy about 0.01nm, which has certain research significance for space laser communication and lidar.