Liquid crystal polarization gratings with wide incidence angle and high diffraction efficiency

Liquid Crystal Polarization Gratings (LCPGs) are highly efficient and versatile liquid crystal devices frequently employed in diverse technologies including light field regulation, beam polarization, and laser radar. A three-layer multi-twist structure of LCPG was prepared using a 266 nm laser interference exposure method, resulting in two types of LCPGs with periods of 7μm and 15μm respectively. Subsequent testing with a 1064 nm wavelength laser and comparison with simulations revealed that the polarization grating can sustain high diffraction efficiency within an incident angle of ±30° at the 1064 nm wavelength. This research paves a way for the applications such as laser radar and beam polarization.

液晶偏振光栅（Liquid Crystal Polarization Gratings，LCPGs）是一类高效且多功能的液晶器件，广泛应用于光场调控、光束偏振、激光雷达等诸多技术领域。本研究采用266nm激光干涉曝光法制备了三层多扭曲结构的LCPGs，得到周期分别为7μm与15μm的两类光栅。后续通过1064nm波长激光开展测试，并与仿真结果对比后发现，该光栅在1064nm波长、入射角±30°的范围内可维持较高的衍射效率。本研究为激光雷达、光束偏振等相关应用开辟了可行路径。