Method and apparatus for controlling thickness of a layer of an optical data storage device by measuring an optical property of the layer
US4676646A · kind A · utility
20Cited by
2References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1985 |
| Grant date | Jun 30, 1987 |
| Priority date | — |
| Expiry date | Oct 15, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/25715
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a method and apparatus for depositing material on a substrate by periodically measuring an optical property of a region thereof, thereby obtaining a substantially continuous profile of the property for that region. The measured value of the property is compared with a predetermined value, and when the two values are substantially equal, deposition is terminated, thereby resulting in correct and reproductible layer thicknesses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.