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:
Mar. 27, 2001
Filed:
Jul. 23, 1998
Misao Fukuda, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
An optical disk apparatus which has first and second light-emitting elements for emitting laser beams, and records data on a recording medium with laser beams from the first and second light-emitting elements includes first and second recording abnormality detectors, first and second protective circuits, and abnormality signal synchronization circuits. The first and second recording abnormality detectors detect abnormalities of recording by the first and second light-emitting elements from beams reflected by the recording medium during execution of recording. The first and second protective circuits immediately stop recording being executed by the first and second light-emitting elements, and protect data on the recording medium when the first and second recording abnormality detectors detect abnormalities. The abnormality signal synchronization circuits inform the second and first protective circuits of abnormalities in synchronism with completion of recording being executed by the second and first light-emitting elements when the first and second recording abnormality detectors detect the abnormalities.