Method and apparatus for thermo magnetic recording/erasing information with preselected magnetic field switching
US4712203A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1985 |
| Grant date | Dec 8, 1987 |
| Priority date | — |
| Expiry date | Jun 12, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B19/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for processing information on a recording member having a recording film capable of recording and erasing information in accordance with the change of a magnetizing direction, by utilizing a light induced thermo-magnetic effect, in which before the intensity of the laser light is switched at the high level eliminating the magnetization of the recording film in order to effect the recording and erasing operations by focusing the laser light on the recording film as a light spot, a magnetic field with the predetermined direction according to the recording and erasing operations is previously applied on the recording film, whereby the recording and erasing operations of the magnetized information can be effected with high speed and stably by applying the normal magnetic field in the direction according to the recording and erasing operations respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.