简单结构超表面实现波长和偏振态同时复用全息显示新方法

A new method of implementing simultaneous multiplexing holographic display of wavelength and polarization state with simple structure metasurface

本文基于衍射光学设计理论,提出了仅用一种简单结构实现波长和偏振态同时复用全息显示新方法.构建了不同入射条件下超表面微元的结构参数与透过相位之间的映射关系,建立了科学的评价函数,优化得到超表面每个像素点处最优的单一结构超表面微元尺寸.仿真结果表明,本文设计的超表面实现了波长为532 nm的x线偏振光和波长为633 nm的y线偏振光入射显示不同形状字符的功能.

In this paper,we propose a new method to realize both polarization-multiplexing and wavelengthmultiplexing using a simple structure,which can realize hologram by the multiplexing of double wavelengths and double polarization in the visible band.Our design can reduce color cross-talk and have a higher diffraction efficiency.We design a transmission metasurface composed of simple rectangular cells.Firstly,we establish the relationship of structural parameters with the transmission phase under various incident conditions of light beams.Then we propose a fitness function that can optimize the structural parameters of the unit cell at each pixel point,which can display different images by 532 nm x-polarization and 633 nm y-polarization incident light beams respectively.Finally,finite difference time domain method is used to analyze the structure,and the holographic result fits the theoretical design very well.This work proposes using single metasurface structure to solve the problems of wavelength cross-talk appearing when using simple structures,and will have great importance in coding and anti-counterfeiting.