Method for manufacturing optical memory disc
US4457794A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1983 |
| Grant date | Jul 3, 1984 |
| Priority date | — |
| Expiry date | Jun 23, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/2432
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Proposed is a method for manufacturing an optical memory disc having a pregrooved substrate and a recording film on the pregrooved substrate. In the step of depositing the recording film on the pregrooved substrate, light is incident on the pregrooved substrate, and at least one of exposure amounts of light reflected by and light transmitted through the pregrooved substrate and the recording film while the recording film is being deposited on the pregrooved substrate is measured. When one of the exposure amounts of light reflected by and light transmitted through the pregrooved substrate and the recording film has reached the corresponding preset exposure amount, the deposition of the recording film is stopped.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.