Browse Prior Art Database

Variable Laser-Read-Power Level

IP.com Disclosure Number: IPCOM000058757D
Original Publication Date: 1988-Dec-01
Included in the Prior Art Database: 2005-Feb-15

Publishing Venue

IBM

Related People

Authors:
Haynes, MK Hunt, RA [+details]

Abstract

This technique described relates to Thermo-Magneto-Optic Storage of digital data on, for example, amorphous films of Rare-Earth transition- metal alloys. Information is stored by heating an area of the disk with a high-power optical laser spot in coincidence with a magnetic bias field whose polarity controls the direction of magnetization in the written mark. The data to be written controls the laser output pulses, so that marks are written only when the laser power is on at the high level. Erasure is performed prior to writing data by passing the area to be erased by a high-level laser spot in coincidence with a magnetic bias field whose polarity is reverse from that used in writing.