“Significant breakthroughs have been made in the field of liquid crystal polarizing gratings. The research team successfully designed and implemented a three-layer structure liquid crystal polarizer grating, and conducted in-depth research on its diffraction characteristics and coupling in optical waveguides. Through theoretical calculations and experimental verification, the diffraction efficiency of the device can reach over 80% at 450 nm, 532 nm, and 633 nm, demonstrating excellent optical waveguide coupling performance. This research achievement not only enriches the theoretical system of liquid crystal polarizing gratings, but also provides new possibilities for the application of optical waveguide coupling devices, which is of great significance for promoting technological progress in related fields.”