Liquid-Crystal-Based Optical Phased Array for Steering Lasers

A paper describes the basic design and concepts of tunable liquid-crystal polarization gratings with a nematic liquid crystal (LC) optical phase plate, with a large, continuous in- plane gradient that is variable, and its application to a beam steering device with high efficiency.To improve the important issue of tuning speed, there is a discussion of the dynamics of discrete changes in the phase profile, and also continuous changes in the phase profile through acquired data and numerical modeling. It is shown that a design based on liquid crystals whose dielectric anisotropy can change sign (as a function of frequency) allows continuous tuning with reasonable response times.