Optical disk and optical disk apparatus
US7778143B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2005 |
| Grant date | Aug 17, 2010 |
| Priority date | — |
| Expiry date | Apr 12, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/24082
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disk according to the present invention includes: a substrate in a disk shape; guide grooves arranged at a pitch p in a radial direction of the substrate, each of the guide grooves being formed so as to extend in a circumferential direction of the substrate; and a pre-pit formed in a space between the guide grooves so as to extend along the guide groove. The optical disk is configured so that an address signal assigned to each location on a signal surface is indicated by the arrangement of the pre-pit in accordance with a predetermined rule. The pre-pit is composed of a pair of pre-pits formed on respective sides of the guide groove. The pair of pre-pits are arranged so as to be displaced in the circumferential direction so that a distance between inner edges of the respective pre-pits in the circumferential direction is smaller than the pitch p of the guide grooves. An optical disk apparatus of the present invention detects light reflected from the optical disk configured as above, calculates a differential phase detection signal, and detects an address signal using the differential phase detection signal. According to this optical disk apparatus, an address signal can …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.