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. 02, 2005
Filed:
Feb. 18, 2004
Yasuhito Soma, Hirakata, JP;
Akira Matsubara, Kameoka, JP;
Kazuhiko Kouno, Takatsuki, JP;
Abstract
The present invention provides an optical disc apparatus which solves a problem that the tracking control takes off when an objective lens is displaced in the tracking direction due to its weight. In this optical disc apparatus, a spot position detectorgenerates a spot position signal which indicates a position of a light spot on a light receiving element, and supplies the signal to a traverse loop filterand a spot position loop filter. A controllersupplies an output from the spot position loop filterto a tracking actuator, before supplying an output from the traverse loop filterto a traverse motor, previously moves the light spot near the center of the light receiving element, and starts the traverse control in a state where a value of the spot position signal at starting of the traverse control is reduced.