| 摘要 |
PROBLEM TO BE SOLVED: To independently diffract two linearly polarized components orthogonal to each other and to separate and detect the highly symmetrical two polarized components by constructing a polarized separation element in such a manner that only a specified linearly polarized component is diffracted and two polarized diffraction gratings transmitting a linearly polarized component orthogonal to the same are stacked to be orthogonal to each other. SOLUTION: Polarized diffraction gratings 41 and 42 diffracting only linearly polarized light beams orthogonal to the gratings are arranged to be orthogonal to each other and made active on two incident linearly polarized light beams. By the polarized diffraction grating 41, only the polarized components orthogonal to the grating generate diffracted light beams. But in the polarized diffracting grating 42, the components are transmitted without being diffracted. On the other hand, the polarized components transmitted without being diffracted in the polarized diffraction grating 41 are diffracted by the polarized diffraction grating 42. Thus, 5 light beams including 0-order light are generated after passing through the polarized diffracting gratings 41 and 42, two opposing diffracted light beams among them are linearly polarized light beams of the same polarizing direction, and adjacent diffracted light beams become linearly polarized light beams orthogonal to each other. |
