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. 29, 2000
Filed:
Jul. 09, 1997
Sony Corporation, Tokyo, JP;
Abstract
A disc playback apparatus for playing back a disc on which data have been recorded under a CLV control is provided with a CLV control section for performing a CLV control, a speed comparator and a reference clock generator for performing a CAV control, a changeover switch for switching between the CLV control and the CAV control, and a CPU for setting a switching point of the changeover switch and controlling the switching of the changeover switch. According to another aspect of the invention, switching is made between a playback with a CLV servo control and a playback with a CAV servo control in accordance with the reproduction scanning position in the disc radial direction. In particular, a difference between disc rotation speeds at the disc innermost and outermost tracks is made smaller than that in a case where a playback is performed at a specific linear velocity over the disc entire area. According to a further aspect of the invention, regions are set by dividing the disc entire area in the disc radial direction. A judgment is made of a region to which a current reproduction scanning position belongs, and control is made so as to switch the playback linear velocity in accordance with the region thus determined. In particular, a difference between disc rotation speeds at the disc innermost and outermost tracks is made smaller than that in a case where the linear velocity is not changed over the disc entire area.