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:
Jul. 23, 2002
Filed:
Nov. 16, 1998
Satoru Oonuki, Toride, JP;
Masafumi Yoshihiro, Kitasouma-gun, JP;
Nobuyuki Nagai, Tsukuba-gun, JP;
Katsusuke Shimazaki, Kitasouma-gun, JP;
Hiroyuki Awano, Noda, JP;
Hiroshi Shirai, Kitasouma-gun, JP;
Norio Ohta, Tsukuba-gun, JP;
Satoshi Sumi, Gifu, JP;
Atsushi Yamaguchi, Ogaki, JP;
Other;
Abstract
A magneto-optical recording medium has, in order from the laser irradiation side, a second auxiliary magnetic film first auxiliary magnetic film and magneto-optical recording film First and second auxiliary magnetic films and change from in-plane magnetization to perpendicular magnetization when their respective critical temperatures T and T are exceeded. The Curie temperatures T , T and T of the magneto-optical recording film and the first and the second auxiliary magnetic films and their critical temperatures T and T satisfy the relationship: room temperature<T <T <T , T ,T . The first auxiliary magnetic layer has a film thickness greater than the thickness of the magnetic wall. In response to irradiation by the reproducing light beam, recording magnetic domain of magneto-optical recording film is transferred, with size reduction, to first auxiliary magnetic film and is then transferred, with magnification, to second auxiliary magnetic film This is ideal for reproduction of a high-density recording medium since an amplified reproduction signal is obtained from magnified magnetic domains