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. 30, 1994
Filed:
Nov. 23, 1992
Katsuya Watanabe, Suita, JP;
Masayuki Shibano, Izumisano, JP;
Hiroyuki Yamaguchi, Hirakata, JP;
Yasuaki Edahiro, Hirakata, JP;
Mitsuro Moriya, Ikomo, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In a tracking control apparatus, a tracking error signal having a level of a positional shift of a beam of light projected through an optical head onto a recording medium is detected based on a reflected light from the recording medium, and the optical head is controlled so that a beam of light scans on the track to be recorded or reproduced based on the tracking error signal. Offset values of the tracking error signal on adjustment tracks which are predetermined among a plurality of tracks of the recording medium are detected, and then coefficients of a predetermined approximate equation approximately representing an offset value characteristic on the track based on the detected offset values are calculated. Further, an offset value corresponding to the track to be recorded or reproduced is calculated based on the first approximate equation with the calculated coefficients, and an offset value of the tracking error signal is corrected based on the calculated offset value.