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:
Sep. 10, 1991
Filed:
Apr. 17, 1990
Shozo Saekusa, Ibaraki, JP;
Seiichi Katoh, Chigasaki, JP;
Akira Ikuma, Hiratsuka, JP;
Hiroshi Saito, Chigasaki, JP;
Isao Shimizu, Ibaraki, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An objective lens driving apparatus has a base provided with focusing permanent magnets and tracking permanent magnets, a supporting shaft mounted on the base, a lens holder for holding an objective lens at an extension thereof, with the lens holder being rotatably and slidably fitted onto the supporting shaft at a position of the center of gravity of the lens holder and being provided with focusing coils and tracking coils. A plurality of substantially identical elastic members are stretched between the base and the lens holder in a plane substantially perpendicular to the supporting shaft and in axisymmetrical relation with respect to Y-axis line joining the supporting shaft and the objective lens and X-axis line substantially perpendicular to the Y-axis. Each of the elastic members is a spring formed by a lead wire extending to the focusing and tracking coils. The springs are secured to the base through a fiscous elastic material.