位相光栅的衍射级次

用矢量衍射理认讨论了位相光栅衍射级次的有限性及其与入射角的关系，得出的吉论与用光程方法得出的结果一致，作出了在不同入射角条件下各衍射级次的分布图，给出了求解各级衍射波方向的公式。

Diffractive Order of Phase Grating

The finiteness of diffractive order of the phase grating and the relations between the diffractive orders and the incident angle are discussed by means of the vector diffraction theory. The results are in correspondence with that attained by the optical path method. The distribuion of each diffractive order is illustrated at different incident angles and the diffractive direction of each diffraction wave are given. It is pointed out that while there only exist the zero-order reflection wave and the zero-order transmit in free space layer, the diffraction waves of higher diffractive orders may exist in the substrate layer.