| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polarization diffraction grating reduced in weight and space as compared with a bulk PBS, and increased in diffraction efficiency. <P>SOLUTION: In a diffraction grating having a periodic, irregular sectional shape, when a medium of a projection and that of a recess are set to be the medium 1 and the medium 2, respectively, an refractive index to s polarization of the medium 1 and an refractive index to p polarization of the medium 1 are set to be n1s and n1p, respectively, and the refractive index of the medium 2 is set to be n2, the relationship of n1s>n2>n1p is met, thus obtaining the plane type polarization diffraction grating 1 of which weight and space are reduced and efficiency is increased as compared with the bulk PBS. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
