台阶光栅衍射效率的傅里叶分析

Fourier analysis to diffraction efficiency of step gratings

用傅里叶方法对台阶光栅衍射效率进行了分析，得出任意台阶数，任意台阶高度的二元光栅任意级次的衍射效率公式。针对二台阶光栅分析了台阶高度，台阶宽度，不同波长对＋１级衍射效率的影响，理论图像清晰，结果简单明了。

Using Fourier transfer,we extend the transparent index function of step grating into Fourier series and derived the expression of diffraction efficiency.The expression shows that the diffraction efficiency is the function of width ratio ξ ,height ratio γ and wavelength ratio σ .As a example,we give the calculation results of diffraction efficiency of 2 level step grating.