Magneto-optical recording medium having intermediate layer of in-plane magnetization
US6147939A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1998 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Mar 2, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10593
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magneto-optical memory medium according to the present invention comprises a reproducing layer, which has in-plane magnetization at room temperature and perpendicular magnetization when heated to above a predetermined temperature by a reproducing light beam; a recording layer, which is magnetostatically coupled to the reproducing layer; and an in-plane magnetized layer, provided adjacent to the recording layer, which has a Curie temperature at the above-mentioned predetermined temperature. In this medium, at temperatures below the predetermined temperature, signals recorded at high density in the recording layer are masked, and the above-mentioned magnetostatic coupling is suppressed, by magnetic masking by the in-plane magnetized layer. At temperatures above the predetermined temperature, however, within a domain forming part of the in-plane magnetized layer, the recording layer and the reproducing layer are magnetostatically coupled, and a recording bit of the recording layer is copied and expanded to a magnetic domain in the reproducing layer. Accordingly, with this medium, by reproducing from an expanded magnetic domain of the reproducing layer, even information from recordin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.