Magneto-optical recorder with compensation for variation in applied magnetic field intensity on a recording medium
US4982389A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 19, 1988 |
| Grant date | Jan 1, 1991 |
| Priority date | — |
| Expiry date | Jan 19, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10571
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magneto-optical recorder comprising an optical head for projecting a light beam on a magneto-optical recording medium so as to form a light spot thereon, a magnetic head disposed at a predetermined distance from the optical head and applying a magnetic field modulated according to information to be recorded to the magneto-optical recording medium; and light intensity controlling means for varying the intensity of the light spot, responding to at least one of a focusing error signal indicating deviations of the light spot from the magneto-optical recording medium and a position signal indicating the relative position of the magneto-optical recording medium and the optical head, wherein, even if the intensity of the magnetic field applied to the recording medium varies, depending on vertical oscillations of the recording medium or on the position of the light spot, influences of variations in the intensity of the applied magnetic field are compensated by varying the intensity of the light spot so that fluctuations in the amount of recorded signals and imperfect erasing are suppressed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.