| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain an optical element which can prevent direct contact of an optical disk and an objective lens, and does not have an adverse affect on recording and reproduction of the optical disk even if a burr etc. occurs due to a protruded section. <P>SOLUTION: The optical element has an optical function section and a flange section. The optical function section has an NA value ≥0.7, and has a first optical function face and a second optical function face which face mutually, and a curvature of the first optical function face is smaller than that of the second optical function face. A plurality of concave parts or convex-parts are prepared on a face by the side of the first optical function face of the flange section, and a protective member comprising a material having elasticity is prepared on a face by the side of the first optical function face of the flange section. <P>COPYRIGHT: (C)2008,JPO&INPIT |
