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.

Date of Patent:
Jan. 18, 2005

Filed:

Jan. 29, 2003
Applicant:

Chikashi Yoshinaga, Gunma, JP;

Inventor:

Chikashi Yoshinaga, Gunma, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 708 ; G11B 7085 ; G11B 709 ;
U.S. Cl.
CPC ...
Abstract

The height of a tracking coil in an objective lens driving device having a cover over a magnetic circuit is freed from limitations imposed by the cover, so that an effective length of the tracking coil can be ensured. Magnetsgenerating an effective flux and facing yokesfacing the magnets are provided such that effective edges of a focusing coiland a tracking coilare located in an air gap. A coveris provided over the top surface of the magnetsand the facing yokes. The coverhas a notch formed for exposing the tracking coilso as to avoid limiting the height of the tracking coil, thereby securing an appropriate effective length of the tracking coilwithin the effective flux.


Find Patent Forward Citations

Loading…