Integrated optical pick-up device
US5060212A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 1988 |
| Grant date | Oct 22, 1991 |
| Priority date | — |
| Expiry date | Aug 15, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/1359
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pick-up device for use in an optical disc information recording/reproducing apparatus is provided. In the present optical pick-up device, the functions of two or more separate optical elements provided in the prior art structure are combined or integrated in a single element to reduce the total number of separate optical elements provided in the device. In particular, use is made of a diffraction grating rather than lenses and/or lenses are formed as holo lenses. A diffraction grating and a holo lens may be formed substantially in the shape of flat plates, to define an optical components can be put together to define an integrated subassembly, which reduces the total number of discrete elements, facilitates manufacturing and eliminates the necessity of adjustments among optical elements once set.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.