Electrically switchable continuous phase liquid crystal Fresnel zone plate
Zhiyu Xu·Stephen M. Morris·Tianxin Wang·Alec Xu·Nathan Spiller·Urban Mur·Martin J. Booth·Steve J. Elston·Camron Nourshargh
Abstract We present the design, fabrication, and characterization of continuous phase Fresnel zone plates (FZPs) using two-photon polymerization direct laser writing in a polymerizable nematic liquid crystal (LC) confined between glass substrates. Unlike conventional binary LC diffractive elements, our devices exhibit a smooth, continuous three-dimensional phase profile. Two devices were demonstrated with wrapped phase profiles of 2 π and 4 π radians, respectively. Polarized optical microscopy a