Apparatus and method for accessing data on multilayered optical media
US5784352A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 1997 |
| Grant date | Jul 21, 1998 |
| Priority date | — |
| Expiry date | Aug 19, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/141
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus and methods for accessing data on a multilayered optical storage medium. The apparatus uses the time-of-flight of illumination directed to and reflected by the layers of the optical medium to access data stored on a desired layer of the medium. More particularly, alterations in illumination reflected from the desired layer are detected to access data stored on the layer. In accordance with embodiments of the invention utilizing interferometric techniques, the time-of-flight of a reference illumination is adjusted to cause interference of the reference illumination with the illumination reflected from the layer which contains the data to be accessed. Alternatively, and in accordance with embodiments of the invention utilizing non-interferometric techniques, the time-of-flight of illumination reflected by the layer which contains the data to be accessed is selected to permit data stored on the desired layer to be accessed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.