光栅作为光通信系统中的色散型波分复用器,系统通常要求其在近掠入射条件下具有高衍射效率,传统设计方法给出的光栅闪耀角大,工艺上不易实现。基于光栅电磁场理论,提出用光栅互易定理计算光栅槽形初始值,结合衍射效率等高线法优化光栅槽形的设计方法—互易定理优化法。结果表明,C波段TM波-1级峰值衍射效率理论值为94.9%,测量值为92.1%。较传统光栅设计方法,互易定理优化法的应用降低了光通信光栅的制作难度,提高了衍射效率,为掠入射光栅的研制提供了更好的途径。 As a dispersive wavelength division multiplexer in optical communication system, the grating usually requires high diffraction efficiency under the condition of near-grazing incidence. The grating designed by the traditional design method has a large blaze angle and is difficult to be realized technically. Based on the theory of grating electromagnetic field, the initial value of grating groove shape was calculated by using the reciprocity theorem of grating, and the optimization method of reciprocity theorem was proposed based on the diffraction efficiency contour line method. The results show that the theoretical value of C-band TM-1 peak diffraction efficiency is 94.9% and the measured value is 92.1%. Compared with the traditional grating design method, the application of the reciprocity theorem optimization method reduces the production difficulty of the optical communication grating, improves the diffraction efficiency and provides a better way for the development of the grazing incidence grating.