optical pickup apparatus
US5764613A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Apr 30, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup apparatus is constructed of an objective lens for condensing a light beam emitted from a light source toward an optical recording medium, and a convex lens arranged between the optical recording medium and the objective lens in which a surface thereof upon which the luminous flux projected from the objective lens is incident is a convex spherical surface with a radius of curvature which is a predetermined value, and another surface thereof which is located near and opposite to a surface portion of the optical recording medium which is a plane. With this arrangement, a tolerance with respect to decentering of the convex lens in connection with the optical axis of the objective lens is increased, so that an occurrence of aberration is reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.