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:
Jan. 17, 2012
Filed:
Apr. 20, 2007
Yuuichi Kuze, Osaka, JP;
Katsuya Watanabe, Nara, JP;
Shinichi Yamada, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An object of this invention is to measure the tilt quantity of, and perform a tilt control on, an optical disc accurately without depending on the rotation control method. An optical disc drive includes: a motor for rotating an optical disc; an optical system for irradiating the optical disc with a light beam; a moving mechanism for moving the optical system along the radius of the optical disc; a focus control section for controlling movement of the optical system perpendicularly to the optical disc based on drive values, thereby focusing the light beam onto a storage layer of the optical disc; and a tilt control section for measuring the tilt quantities of the storage layer at multiple different radial locations on the optical disc based on drive values for the respective radial locations when the focus control section focuses the light beam there. When the tilt control section measures the tilt quantities, the motor keeps the rotational frequency of the optical disc constant and the tilt control section uses the drive values obtained at the respective radial locations.