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:
Aug. 04, 2009
Filed:
Jan. 26, 2005
Satoshi Iwasaki, Tamana, JP;
Shinji Matsumoto, Tamana, JP;
Hideyuki Fujishima, Fukuoka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
During recording with an optical disk apparatus, an objective lens is moved toward the inner circumference and outer circumference of an optical disk in the radial direction thereof and also moved upward and downward, and the quantity of reflected light is measured at that time. Quantities of reflected light are determined taking advantage of the characteristic of laser heat that it is most efficiently used to provide the smallest quantity of reflected light when the relationship between the optical disk surface and the objective lens is closest to perpendicularity and when they are at a distance at which the point in focus is most closely approached. An optimum tilt value and focus position are learned from the result of the determination to allow operations to be performed at the optimum tilt and the optimum position of the point in focus.