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:
Jun. 12, 2001
Filed:
Oct. 16, 1998
Sony Corporation, Tokyo, JP;
Abstract
A malfunction during focussing pull-in in an optical disc recording/reproducing apparatus is to be prevented. To this end, the optical disc recording/reproducing apparatus includes an optical pickup,having an objective lens,and a biaxial actuator, a photodetector for generating tracking error signals from the return light of the laser light illuminated on the optical disc and a position sensor for detecting the position of the objective lens relative to the optical disc. The optical disc recording/reproducing apparatus also includes an actuator driving circuit for controlling the servo operation of a biaxial actuator,, based on the tracking error signals, so that the converging point of the light beam will be on the signal recording surface of the optical disc, and a pull-in range decision unit for outputting a permission signal according permission for the servo operation when the position of the objective lens,is within a preset range.