Optical disc with pit interval and depth for maximum visual effect
US6490239B1 · kind B1 · utility
11Cited by
10References
2Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 18, 2000 |
| Grant date | Dec 3, 2002 |
| Priority date | — |
| Expiry date | Oct 18, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B23/38
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disc has the effect of indicating characters and pictures formed thereon by making use of a diffraction phenomenon in areas formed with many pits. The value of the pit interval is selected to provide an improved optical disc capable of clearly indicating the characters and pictures. A relationship between pit interval and the light intensity of a diffracted light is calculated. In accordance with this calculation, the pit interval is set to be within a range from 570 nm to 1000 nm, thereby increasing the light intensity of the diffracted light, thus making it possible to clearly indicate characters and pictures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.