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:
Apr. 27, 1999
Filed:
Aug. 27, 1997
Taizo Takiguchi, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A driving device and a calibration method for an ablation write-once type optical disc in which the recording light volume can be calibrated accurately without using an over-power for positively recording data on the ablation write-once type optical disc. A playback output by an optical head 3 for recording/reproducing data by scanning an ablation write-once type optical disc 1 with a laser light beam is supplied to an optimum recording light volume decision unit 4. A light recording data controller 6 controls a laser driving controller 5 for controlling the laser light volume of an optical head 3 for recording two different recording patterns with different repetition periods with various recording light volumes. The optimum recording light volume decision unit 4 detects the asymmetry amount from the playback outputs of the two different recording patterns and determines an optimum recording light volume of the ablation write-once type optical disc 1 based on the asymmetry amounts at the various recording light volumes.