Increased intensity optical recording medium with adjacent grooves of different optical depth and a method and apparatus for reproducing the same
US5553051A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1995 |
| Grant date | Sep 3, 1996 |
| Priority date | — |
| Expiry date | Mar 10, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/00454
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical recording medium on which information is recorded by irradiating the medium with a light spot to cause a characteristic change of an actual reflection factor, the optical recording medium including grooves of different optical depths which extend in a direction in which the light spot is moved relative to the medium and which are alternately and periodically formed in a direction perpendicular to the relative movement direction of the light spot so that a plurality of grooves thereof can be covered by the light spot, and mark recording regions provided on the flat surfaces between the grooves, the pitch of the flat surfaces between the grooves being selected to be substantially half the diameter of the light spot, thus increasing the recording density and preventing the cross-talk. A method and apparatus for reproducing the information recorded on the medium are provided. Of the reflected and diffracted light distribution obtained by irradiating the light spot on the optical recording medium, the intensity change of the 0-order and third-order interference regions on the shallow groove's side are detected in the form of electrical signals, and information signals corresp…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.