When the polarization of the probe beam changes from p-polarized to s-polarized, the grating diffracts s-polarized +1 st order and p-polarized -1 st order, respectively.

• 当探测光为垂直方向振动的线偏振光时,衍射级中只观察到零级和负一级衍射,无正一级衍射,并且衍射级的偏振态与探测光的偏振态相互正交。