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:
Feb. 03, 2009
Filed:
Jun. 14, 2005
Kousei Sano, Osaka, JP;
Yoshiaki Komma, Hirakata, JP;
Sadao Mizuno, Ibaraki, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An optical head which is capable of realizing a stable tracking control, even if the rotational center of an information recording medium is not located on the extension line of the transfer directions of a light-concentrating element, includes: a semiconductor laser which emits a beam of light; an objective lens which concentrates the beam of light on an optical disk; a transfer mechanism which transfers the objective lens between the outermost circumference and the innermost circumference of the recording area of the optical disk along the optical disk; and a photo-detector which detects a beam of light that returns from the optical disk. The photo-detector includes a plurality of areas which are divided by a division line. The division line is set parallel to the tangential directions of the track in a predetermined position on the transfer line of the objective lens between the outermost circumference and the innermost circumference of the recording area, and the plurality of areas are divided, by a lateral division line which intersects the division line, into a first area on which a beam of light that mainly includes a tracking component is incident and a second area on which a beam of light that does not include the tracking component is incident.