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. 06, 1981
Filed:
Oct. 05, 1979
Yuji Togami, Isehara, JP;
Nippon Hoso Kyokai, Tokyo, JP;
Abstract
A recording medium consists of a composite amorphous magnetic material layer comprising a rare earth metal and an iron family metal, the composition ratio thereof being nonuniform in the perpendicular direction. Because of the nonuniform composition ratio, a minute magnetic domain can be formed stably, so that thermo magnetic recording at extremely high density and sensitivity can be effected. Where GdFe is employed as a suitable material, the thickness of a portion of the magnetic layer, which portion has a larger perpendicular magnetic anisotropy caused by the nonuniform composition ratio, is increased preferably in comparison with the other portion. Uniform thermo magnetic recording can be performed on the large area medium by covering the same with a transparent dielectric material layer having nonuniform thickness.