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

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.