Flying type optical head integrally formed with light source and photodetector and optical disk apparatus with the same
US5715226A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1995 |
| Grant date | Feb 3, 1998 |
| Priority date | — |
| Expiry date | Jun 2, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/3432
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The optical head is arranged such that a semiconductor laser and a photodetector are formed via a buffer layer on the same substrate; and an opening portion is formed in the substrate under the semiconductor laser and the photodetector. This optical head is further arranged by that the opening portion is filled with a first transparent layer; a diffraction grating is formed on a lower surface of the first transparent layer; a second transparent layer is stacked on a lower surface of the first transparent layer; and a condenser lens is formed on a lower surface of the transparent layer. In this optical head, laser light emitted from the semiconductor laser is penetrated through the substrate, the first transparent layer, the diffraction grating, and the second transparent layer, and condensed toward a place just under the condenser lens by the condenser lens, thereby forming a light spot on an optical storage medium positioned apart from the condenser lens, whereas reflection light reflected from the optical storage medium is penetrated through the condenser lens and the second transparent layer, diffracted by the diffraction grating toward a light receiving plane of the photodetect…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.