High density optical storage and retrieval using the electromagnetic absorption spectrum to represent multiple bit information
US6479214B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Apr 23, 1996 |
| Grant date | Nov 12, 2002 |
| Priority date | — |
| Expiry date | May 22, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/146
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus for retrieving information stored on an optical disk as colored dots, using an array of laser diodes emitting multiple wavelengths. Colored dots store more information than pits and spaces on optical disks because each colored dot represents a multiple-bit code of information rather than a single bit. The optical disk reader directs multiple wavelength diode laser beams to the disk surface. The reflected beams are then separated using an array of dichroic filters, and sent to light sensors. The light sensors identify the intensity of each of the reflected frequencies and determine the wavelength combination being reflected from the optical disk, which corresponds to a multiple-bit code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.