Optical information medium
US6603733B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 2001 |
| Grant date | Aug 5, 2003 |
| Priority date | — |
| Expiry date | Mar 2, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/266
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information disk with an excellent mechanical precision is provided. Also provided is a multi-layer optical disk having a plurality of data layers wherein every data layer exhibits sufficient properties in reading. In addition, such multi-layer optical disk is provided at a low cost. The optical information comprises a disk-shaped substrate or a pair of disk-shaped substrates, and at least one annular data layer for storing at least recorded information and at least one annular resin layer disposed on said disk-shaped substrate or between said pair of disk-shaped substrates. In this medium, at least one of the substrate(s) has a configuration such that its surface facing toward the data layer is convex, and at least one of said resin layer(s) is formed such that it is thicker near its outer periphery compared to the region near its inner periphery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.