Magnetooptical recording medium allowing overwriting with two or more magnetic layers and recording method utilizing the same
US5132945A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1990 |
| Grant date | Jul 21, 1992 |
| Priority date | — |
| Expiry date | Jan 30, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10591
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetooptical recording medium provided with a first magnetic layer and a second magnetic layer having a higher Curie point and a lower coercive force than the first magnetic layer and being exchange coupled with the first magnetic layer satisfies the relation: ##EQU1## wherein H.sub.H is the coercive force of the first magnetic layer; H.sub.L is the coercive force of the second magnetic layer; M.sub.2 is the saturation magnetization of the second magnetic layer; h is the thickness thereof; and .sigma..sub.w is the magnetic wall energy between the first and second magnetic layers and a method of recording information on the same.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.