Abnormality detection of a recording medium in a magneto-optical recording system
US5341359A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 1992 |
| Grant date | Aug 23, 1994 |
| Priority date | — |
| Expiry date | Sep 16, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/20
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magneto-optical recording and/or reading-out apparatus can record and read out information on and from a magneto-optical recording medium by the use of a laser beam. The apparatus includes a reflected beam detector, a comparator operatively coupled with the reflected beam detector, and a judgment unit operatively coupled with the comparator. The reflected beam detector detects the quantity of a laser beam reflected from the magneto-optical recording medium during recording. The comparator compares the quantity of the reflected laser beam with at least one reference value during the recording, thereby detecting an abnormality in the reflected laser beam. The judgment unit judges whether an area of the magneto-optical recording medium which has caused the abnormality is practically usable, in accordance with an output from the comparator and data to be recorded on this area.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.