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. 26, 2001
Filed:
Aug. 05, 1999
Young-Do Choi, Seoul, KR;
L G Electronics Inc, Seoul, KR;
Abstract
An apparatus and method for automatically controlling the focusing of a compact disc player (CDP) performs more reliable automatic control operation upon abnormal conditions of a disc, such as a scratch and dust. The automatic focus controlling apparatus includes a pickup assembly for reading recorded data from a disc; and RF signal converter for converting the output signal read by the pickup assembly into an RF signal; a signal separator for separating a signal corresponding to a 3T component from the RF signal; a phase comparator for comparing the separated 3T signal with a predetermined frequency to provide a phase difference value; and a controller for controlling a focusing operation of an objective lens based on the phase difference value to provide a focus control signal.