Optical disc and apparatus for manufacturing a master disc therefor
US6882615B2 · kind B2 · utility
2Cited by
3References
2Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 29, 2001 |
| Grant date | Apr 19, 2005 |
| Priority date | — |
| Expiry date | Apr 26, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31776
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A master-disc-manufacturing apparatus includes an electron-beam emitting portion for emitting an electron beam, an electron-beam converging portion for converging an electron beam, a retarding voltage applying portion for applying a substrate with a negative potential having a magnitude of decelerating the electron beam, and a vacuum atmosphere producing portion for evacuating a chamber to produce a vacuum atmosphere therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.