中文说明：该程序可以计算一维光栅的色散曲线，同时可以推广到一维光子晶体结构，研究光子晶体的色散及能带。该程序对于设计光栅器件，滤波器、反射器等大有帮助。另外一个小程序可以用于布儒斯特角的计算。
English Description：
The program can calculate the dispersion curve of one-dimensional grating, and can be extended to one-dimensional photonic crystal structure to study the dispersion and energy band of photonic crystal. The program is very helpful for designing grating devices, filters and reflectors. Another small program can be used to calculate Brewster angle.