中文摘要：

基于MOEMS（Micro—opto—electro-mechanical Systems）的光栅平动式光调制器依靠结构中的蟹型悬臂梁在静电力作用下的上下运动来改变可动光栅和下反射面的距离，从而实现对光能量的调制。本文依据傅里叶光学对光栅平动式光调制器（Grating Moving Light Modulator，GMLM）工作状态的光学特性进行了详细的理论分析和计算机仿真。分析了可动光栅的光栅周期数为偶数和奇数时，由于几何中心的不同，使得采用傅里叶光学分析时透过率函数不同的问题，并对GMLM衍射光能量的分布进行了详细的理论推导；重点讨论了GMLM结构中边框和蟹型悬臂梁对对比度的影响。结果表明，为了得到较高的对比度，应减小边框宽度、悬臂梁的宽度和长度，文章用图形给出了直观说明。

英文摘要：

The light modulator based on Micro-opto-electro-mechanical System（MEMS） has already become a research focus in projection display field. The structure of Grating Moving Light Modulator （GMLM） supported by four crab-cantilevers is composed of reflection plate, address electrode, four crab-cantilevers and grating plate. In this paper, the influence of crab-cantilevers on GMLM performance was analyzed. The diffraction intensity of GMLM was discussed with Fourier optics, while the grating period number was odd and even integer. Especially, the influence of frame and four crab-cantilevers on GMLM performance was analyzed in detail. The result indicates that frame and crab-cantilever size should be reduced in design for obtaining a higher constrast ratio. Moreover, the relationship between contrast ratio and important structure parameter is shown in figures.