| 摘要 |
PROBLEM TO BE SOLVED: To reduce a noise light beam generated between a convex spherical lens and an optical information recording medium. SOLUTION: On a optical information recording medium D1 side of the convex spherical lens 10, an antireflection means 11 is provided. The reflectance of a light beam can be suppressed at a low level by the antireflection means 11, and a reflected light component is hardly generated in an air gap G1. Thereby, multiple-beam reflection is not generated, and the noise light beam generated between the convex spherical lens 10 and the optical information recording medium D1 can be reduced. |
