Electrically Switchable Fresnel Lens Based on a Liquid Crystal Film with a Polymer Relief Pattern

Abstract

This investigation elucidates a Fresnel lens using a simple approach that is based on a homogeneously aligned liquid crystal (LC) film with a preformed polymer relief pattern. Experimental results demonstrate that the LC Fresnel lens has polarization-dependent and electrically switchable focusing features. The LC lens has the further advantages of a weak operated field (∼1.3 V/µm), and high diffraction efficiency (∼34%).