Secondly, the analysis of the retro-diffraction in an EDG is given by using a Finite-Difference Time-Domain (FDTD) method combined with perfectly matched layers (PML) and a periodic boundary condition.

• 利用时域有限差分法对光栅的后向衍射效率进行了分析,比较了全内反射(TIR)光栅结构和普通光栅在后向衍射效率上的差别,及其适用范围。