Simulation analysis of a reorientation of liquid crystal molecules in a liquid crystal lens with Fresnel structure

Abstract

Liquid crystals (LCs) possess great potential for tunable optical elements such as lenses and deflectors. We have recently developed a novel LC lens device based on a Fresnel structure. In these devices, high-resistivity and insulating thin films are placed such that a saw-tooth distribution of voltage is formed in the LC layer. In this study, we numerically analyze the reorientation of the LC director and the resulting optical phase retardation in Fresnel-type and standard-type LC lenses, and compare their performance. In particular, we consider the molecular twist induced in the LC layer by the in-plane component of the voltage distribution, and investigate its dependence on the device structure.