Optical information recording apparatus, optical recording medium, and method or judging tracking polarity of optical recording medium
US6122243A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 26, 1998 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | Feb 26, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10515
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A tracking groove comprising a land area and a groove area is previously provided on a substrate of an optical disk, and a prepit is previously provided on a boundary line between the land area and the groove area of the tracking groove. When information is recorded on both the land and groove areas, a half-split photodetector split into two parts by a splitting line perpendicular to the radial direction of the optical disk is used as a photoreceiver for receiving light reflected from the optical disk. The photoreceivers are switched so that light reflected from the prepit is reproduced as a signal in any one of the two photodetectors. This enables reproduction signals derived from light reflected from the prepit to be reproduced at a good S/N ratio, thus realizing an optical information recording apparatus which bas a simple construction and enables information to be recorded on both the land and groove areas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.