有限元法结合周期边界条件分析介质光栅衍射

Finite element method of solving diffraction problem of dielectric optical grating

应用周期边界条件建立了分析介质周期结构散射问题的有限元格式。求解域仅为周期结构的一个栅单元尺寸。分析计算了位相型透射光栅的衍射效率 ,栅单元结构分别为矩形和直角三角形。由于有限元方法的离散网格可以很好地匹配介质边界 。

The finite element formulation incorporated with periodic boundary condition is presented for solving diffraction problem of dielectric optical gratings. The method is applied to study the diffraction characteristics of transmission type optical gratings with rectangular and right triangle shapes in the case of incidence of TE polarization plane wave. The required computational resources are small since the size of space domain to be solved is about only a single cell of the dielectric periodic structure.