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:
Nov. 20, 2012
Filed:
Mar. 19, 2009
Noboru Onojima, Saitama, JP;
Shingo Matsuzaki, Gunma, JP;
Noboru Onojima, Saitama, JP;
Shingo Matsuzaki, Gunma, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
An objective-lens-driving apparatus comprising: a base opposed to a signal surface of an optical disc; an objective-lens holder including an objective lens, first and second focusing coils arranged across the objective lens in a tracking direction of the disc, first and second tracking coils arranged across the first-focusing coil in a tangential direction of the disc, and third and fourth tracking coils arranged across the second-focusing coil in the tangential direction, the objective-lens holder being supported on the base movably in a focusing direction of the disc and the tracking direction; and first to fourth magnets arranged on the base to be respectively opposed in the tangential direction to the first to fourth tracking coils, the first and second magnets each having two poles polarized in the tracking direction, magnetization widths of the two poles with respect to the first-focusing coil in the tracking direction being different from each other.