本文以余弦光栅的衍射特性为基础，利用傅里叶分析法，讨论了刻划透射光栅的衍射场，得到的衍射场与利用传统干涉衍射分析法得到的光栅衍射规律相同，总结了光栅衍射场与光栅结构之间的定量关系，归纳了分析光栅衍射的统一方法，这对学生正确理解光栅衍射具有一定的意义.

 Based on the diffraction characteristics of cosine gratings, Fourier analysis is applied to discuss the diffraction pattern of a transmission grating. The diffraction field is the same as the grating diffraction law obtained by the traditional interference diffraction analysis method. The quantitative relationship between grating diffraction field and grating structure is summarized, and a unified method for analyzing grating diffraction is concluded, which is significant for students to correctly understand grating diffraction.