Optical head assembly
US6125092A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1998 |
| Grant date | Sep 26, 2000 |
| Priority date | — |
| Expiry date | Aug 7, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/22
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical assembly comprises a light emitting device and an objective lens for converging light emitted from the light emitting device onto an optical recording medium. A first diffraction grating is included in which a first grating pattern is formed for diffracting said light emitted from the light emitting device to guide it to the objective lens. Also included are a light receiving element and a second diffraction grating in which a second grating pattern is formed for diffracting returning light from the optical recording medium to guide it to the light receiving element. First alignment marks are provided to either the first or second grating for aligning the diffraction grating having the marks with another element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.