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. 17, 2000
Filed:
Jun. 10, 1999
Applicant:
Inventors:
Hiroshi Ohsawa, Ichihara, JP;
Hiroyuki Watanabe, Ichihara, JP;
Assignee:
Showa Denko K.K., Chiba, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; B29D / ;
U.S. Cl.
CPC ...
264-133 ; 21912169 ; 264-137 ; 264400 ; 4251744 ; 425810 ;
Abstract
A magnetic recording medium having a substrate disc with microscopic bumps formed by focusing a laser beam, wherein spacings D between adjacent bumps in the circumferential direction of the disc are varied so that formula (1) is satisfied: