| 摘要 |
PROBLEM TO BE SOLVED: To provide a grating having high optical use efficiency when guiding light with a different wavelength made incident from different two points onto the same point, and to provide an optical pickup provided with such a grating. SOLUTION: In a grating (10) on which a plurality of linear protrusions are arranged in parallel on a flat surface (11), the cross sections of the protrusions are almost triangular (12) when the protrusions are cut by a plane (the plane of Fig. (1)) perpendicular to the longitudinal direction of the protrusions. |
