Research on typical programmable diffractive optical elements based on liquid crystal spatial light modulator

Abstract

Referring to low designed freedom and high cost of conventional optical element, a method of realizing programmable diffractive optical elements which are based on liquid crystal spatial light modulator is studied. Firstly, liquid crystal spatial light modulator with pixels structured characteristics analyzed; secondly, the phase modulation functions of diffractive optical elements are encoded by computer and the corresponding calculating liquid crystal spatial light modulator programmable software for generating phase functions is developed; finally, the phase patterns of several typical diffractive optical elements (such as Fresnel phase lens, digital blazed grating, axilens) are displayed on liquid crystal on silicon, thus the corresponding diffraction patterns can be obtained. The experiment results verify the efficiency and accuracy of the method in the paper. Compared with conventional optical element, the proposed method can greatly improve the flexibility for fabricating the corresponding diffractive optical elements which are encoded by computer, which is suitable for various occasions for wavefront modulation.