| 摘要 |
<P>PROBLEM TO BE SOLVED: To secure the reliability of inspection inexpensively without needing complicated operation in the inspection of an objective lens for an optical recording medium. <P>SOLUTION: In an inspection method of the objective lens for the optical recording medium, a parallel flat plate for inspection instead of a protective layer of the optical recording medium is inserted in an optical path of light condensed by the objective lens when the objective lens of the optical recording medium which is so designed that light emitted from a light source is condensed in a prescribed position of the optical recording medium via a light transmissible protective layer of the optical recording medium is inspected. As the parallel flat plate for inspection, the one made of a plastic material and having ≤40 nm birefringence or ≤0.1% water absorption is used. <P>COPYRIGHT: (C)2011,JPO&INPIT |
