光栅平动式光调制器光学特性分析

摘要

提出了一种基于微光机电系统的可用于投影显示及相关器件的新型光栅光调制器,介绍了其结构、工作原理和加工流程.对器件进行光学分析,优化和仿真,得出器件结构参数与光学特性之间关系.器件的可动光栅占空比e=0.5,光栅常数d=6 μm,长度L=39 μm,宽度w=36 μm,边距w0=1.5 μm时,理论上±1级衍射效率η=37.0%,对比度V=625;可动光栅与下电极在开态和关态时间距分别为0.65 μm和0.78 μm,器件单像素尺寸为51 μm×51 μm.%This paper presents a novel grating moving light modulator based on Micro Optical Electromechanical System(MOEMS) technology and introduces its structure,operation principle and fabrication process. The device can be used in projection display etc. The relationship between optical characteristics and geometrical parameters of this device is established through optical analysis, optimization and simulation,and the ±1st order diffraction efficiency η and contrast V are theoretically 37.0% and 625 respectively for e=0.5,d=6 μm,L=39 μm,w=36 μm,w0=1.5 μm and e,d,L,w and w0 are occupation ratio,grating constant, length,width and margin of the movable grating respectively, the gap between the movable grating and the underlying reflector are 0.65 μm and 0.78 μm respectively in on and off states, and the single pixel size of the device is 51 μm×51 μm.