基于严格耦合波理论分析了光栅面形误差对亚波长金属光栅偏振器偏振性能的影响.通过对数值结果的分析发现,光栅圆角误差、光栅侧壁倾斜误差和光栅表面粗糙误差对光栅的TM透射效率影响不大,但它们使得光栅的消光比明显降低.因此,面形误差使得光栅的偏振性能明显降低.理论分析表明,顶角为直角、侧壁垂直和表面光滑的理想矩形光栅结构的偏振性能最好.

The effects caused by grating profile error on the polarization performance of sub-wavelength wire-grid polarizer were analyzed based on RCWT.The analysis of numerical value shown that rounded corners,sidewalls slope and surfaces roughness do not have a significant effect on the TM transmission efficiency,but they have a great effect on the extinction ratio.Therefore grating profile error has a negative effect on the polarization performance of the sub-wavelength wire-grid polarizer.The results show that sub-wavelength wire-grid polarizers perform best when they have sharp corners,vertical sidewalls and smooth surfaces.