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. 11, 2006
Filed:
Nov. 08, 1999
Katsusuke Shimazaki, Toride, JP;
Yuuji Yamazaki, Toride, JP;
Hikaru Mizutani, Minoh, JP;
Tsuyoshi Maro, Otokuni-gun, JP;
Kenji Ohta, Otokuni-gun, JP;
Hiroyoshi Takagi, Kameoka, JP;
Katsuhiro Takahashi, Kyoto, JP;
Katsusuke Shimazaki, Toride, JP;
Yuuji Yamazaki, Toride, JP;
Hikaru Mizutani, Minoh, JP;
Tsuyoshi Maro, Otokuni-gun, JP;
Kenji Ohta, Otokuni-gun, JP;
Hiroyoshi Takagi, Kameoka, JP;
Katsuhiro Takahashi, Kyoto, JP;
Hitachi Maxell, Ltd., Ibaraki, JP;
Abstract
An optical diskis provided with a hubat the central portion of a substratel. A relationship Y/X≧0.015, preferably Y/X≧0.05 is satisfied where X is the projected area of the substrateand Y is a contact area between the huband the substrate. As result, no slippage occurs between the huband the substrateeven when they are rotated at high speed than conventional. With this higher rotational speed, the data transfer rate is improved, and irregular rotation and the camming are suppressed, thereby reducing tracking errors and write/read errors.