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:
Oct. 03, 2000
Filed:
Apr. 19, 1999
Koji Matsumoto, Kawasaki, JP;
Keiji Shono, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A magneto-optical recording medium composed of a plurality of magnetic layers including a rare earth metal and a transition metal as main components. The magneto-optical recording medium includes a magnetic reproducing layer having an easy axis of magnetization perpendicular to a film plane, and a magnetic control layer formed over the magnetic reproducing layer and having an easy axis of magnetization in a plane at a room temperature. A magnetic moment of the rare earth metal of the magnetic control layer being predominant over a magnetic moment of the transition metal of the magnetic control layer. The magnetic control layer includes at least Gd as the rare earth metal and Fe as the transition metal. The magneto-optical recording medium further includes a magnetic recording layer formed over the magnetic control layer and having an easy axis of magnetization perpendicular to the film plane. A Curie temperature Tc1 of the magnetic reproducing layer, a Curie temperature Tc2 of the magnetic control layer, and a Curie temperature Tc3 of the magnetic recording layer are related to satisfy Tc1>Tc2 and Tc3>Tc2. A coercive force Hc1 of the magnetic reproducing layer at the room temperature and a coercive force Hc3 of the magnetic recording layer at the room temperature are related to satisfy Hc3>Hc1.