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:
Dec. 31, 1996
Filed:
Dec. 15, 1994
Akira Kashiwakura, Yuuki-gun, JP;
Katsusuke Shimazaki, Kitasouma-gun, JP;
Masafumi Yoshihiro, Yuuki-gun, JP;
Shin-Itsu Kinoshita, Toride, JP;
Norio Oota, Kitasouma-gun, JP;
Hisanori Sugiyama, Tsukube, JP;
Hitachi Maxell, Ltd., Ibaraki-ken, JP;
Abstract
A magnetooptic recording medium which includes a substrate and a magnetooptic recording film thereon, the substrate having a surface comparted into a plurality of tracks on which magnetooptic recording signals are recorded, and a part of the tracks, selected from the plurality of tracks, including clusters of pre-pits wherein a variation of a change in light amount due to local birefringence in the vicinity of the pre-pits is not more than 20% with respect to a change in light amount in the absence of the local birefringence, when signals from the tracks with recorded magnetooptic recording signals are measured by changes in light amount on the basis of Kerr rotational angles of reflected light from the medium, which magnetooptic recording medium can be effectively used for a ZCAV system.