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:
Apr. 20, 1999
Filed:
Oct. 10, 1997
Applicant:
Inventors:
Yoichi Tsuchiya, Hashima, JP;
Hitoshi Terasaki, Gifu, JP;
Shuichi Ichiura, Hashima, JP;
Toshio Ito, Hashima, JP;
Yasuyuki Kano, Hashima, JP;
Yoshimoto Yamaguchi, Gifu, JP;
Seizo Kato, Ogaki, JP;
Osamu Ota, Ibi-gun, JP;
Assignee:
Sanyo Electric Co., Ltd., Moriguchi, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
3692754 ; 3692753 ;
Abstract
A high density optical disc having a track pitch of 0.85 .mu.m, a shortest pit length of 0.49 .mu.m, a pit depth of 100 nm, and a pit width of 0.35 .mu.m is rotated at a linear velocity of 2.4-2.8 m/s such that the same is optically reproduced by a laser beam having a wavelength of 635 nm which is converged to a spot size of 0.9 .mu.m by an objective lens having a numerical aperture of 0.6. Accordingly, data is read from the optical disc at a transfer rate of 5.6 Mbps.