Method for erasably recording data by viscoelastic shear deformation
US4780867A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 1986 |
| Grant date | Oct 25, 1988 |
| Priority date | — |
| Expiry date | Oct 2, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/24
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An erasable optical data storage medium has a polymer dual recording layer including an expansion layer bonded to a retention layer, each of the layers dyed to selectively absorb light in respective narrow wavelength bands. The retention layer has a glass transition temperature substantially above the glass transition temperature of the expansion layer, and is capable of undergoing substantial viscoelastic shear deformation while below its glass transition temperature. A first laser beam heats the expansion layer causing it to expand and cause viscoelastic deformation in the retention layer while the retention layer is below its glass transition temperature. A second laser beam is used to heat the retention layer above its glass transition temperature and relax the deformation, erasing the medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.