采用了Ｈａｎｓｅｎ矢量波函数理论研究半圆形金属光栅的衍射效率问题。该方法适用于任意入射方向，任意偏振态入射场衍射问题的研究。结果表明，当入射光为ｐ或ｓ型偏振光时，其结果与文献［１］的结果相同 The Hansen vector wave function theory was used to study the diffraction efficiency of semicircular metal grating. The proposed method is suitable for the diffraction problem of incident light in any incident direction and in any polarization state. The results show that when the incident light is p or s-polarized light, the result is the same as the result of [1]