Method of recording information on a record carrier of the thermomagnetic type, and device for carrying out the method
US5126985A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1991 |
| Grant date | Jun 30, 1992 |
| Priority date | — |
| Expiry date | May 14, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B13/045
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
When information is recorded on a record carrier (1) of the thermomagnetic type, the thermomagnetic recording layer (4) is scanned by a magnetic field generated by a magnetic-field modulator (7). The magnetic field is modulated depending on an information signal (Vi). Moreover, the scanned portion of the record carrier (1) is at the same time locally heated by radiation pulses (10) generated by an optical scanning device (5). By means of radiation pulses (10) the record carrier is heated above a write temperature (Ts), above which temperature the magnetization of the record carrier assumes the direction dictated by the magnetic field. A synchronizing circuit (9) generates the control signal (Vm) for modulating the magnetic field and the control signal (Vr) for generating the radiation pulses, in such a way that at the end of the radiation pulses the field strength is sufficiently high for the heated area of the record carrier to be magnetized in the directio dictated by the magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.