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:
Aug. 03, 2004
Filed:
Sep. 01, 2000
Yoshiaki Hara, Hitachinaka, JP;
Takahiko Sugawara, Atsugi, JP;
Yutaka Shimizu, Atsugi, JP;
Takuya Uzumaki, Atsugi, JP;
Atsushi Tanaka, Atsugi, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A magnetic recording medium with a high recording density has a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer successively deposited as the recording layer on a non-magnetic substrate. The recording layer is heated in concentric circular shapes to divide it into regions in which the magnetic interactions between the ferromagnetic layers exhibit ferromagnetism and regions that exhibit anti-ferromagnetism. The ferromagnetic regions are used for recording tracks, and the anti-ferromagnetic regions function as guard bands. In this manner track density is increased without roughening the surface of the recording medium.