The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 14, 1992
Filed:
Jun. 23, 1989
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A method of magneto-optically recording and erasing information which comprises irradiating pulse-like laser beam onto a magneto-optical information storage medium including recording and bias layers which has perpendicular magnetic anisotropy and which are stacked one upon the other to apply coupling interaction which is mainly magnetostatic interaction to each other, and magnetization-reversing temperature of the bias layer being higher than that of the recording layer. When the recording laser beam is irradiated onto the medium, the beam-irradiated portion of the medium is heated to form a reversed magnetic domain in the bias layer, magnetization of the recording layer is reversed by first leakage magnetic field applied to the recording layer when beam-irradiated portion is then cooled, and magnetization of the bias layer is directed in same direction as that under initial state by second leakage magnetic field, applied to the bias layer. When the erasing layer beam is irradiated onto the medium, the beam-irradiated portion of the medium is heated to the magnetization-reversing temperature of the recording layer, and due to third leakage magnetic field applied to the recording layer at this time, the direction of magnetization of the recording layer is re-reversed.