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. 19, 2003
Filed:
Dec. 01, 1998
Kei Tanaka, Hamamatsu, JP;
Minoru Saito, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
Information recording area of an optical disk is divided radially into a plurality of recording areas with a boundary area interposed therebetween. The boundary area is formed as either a high-reflection area that presents a higher reflection light level than the divided recording areas or a low-reflection area that presents a lower reflection light level than the divided recording areas. When an instruction is given to move an optical head from a current point to the target point over the optical disk, a seek operation is performed up to the start point of one of the divided recording areas that contains the target point, while detecting, on the basis of a variation in the reflection light level, the boundary area located between another one of the divided recording areas that contains the current point and the divided recording area containing the target point. Then, a further seek operation is performed up to the target point by calculating a distance, from the start point of the divided recording area containing the target point, to the target point. With this arrangement, a method is provided which can perform an appropriate seek operation at high speed even on an optical disk that mixedly includes areas of different recording densities.