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. 25, 1987
Filed:
Dec. 05, 1985
Yoshio Miura, Yokohama, JP;
Yukio Fukui, Machida, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In the case where an information signal is optically recorded on the tracks of a disc-like recording medium, the apparatus of the invention confirms that no information signal is recorded on the track prior to recording the information signal in order to prevent the overlap recording of the information signal. This apparatus has a track jump pulse generating circuit and an RF signal detecting circuit and the light spot sequentially moves to the adjacent tracks by a plurality of times during one rotation of the track. The presence or absence of an RF signal is detected from each track and the presence or absence of the recorded track is checked at a high speed.