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:
Jul. 20, 1993
Filed:
May. 21, 1991
Mitsuo Oshiba, Hachioji, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A data recording/reproducing apparatus for recording/reproducing data by use of a recording medium comprises a detector for receiving light beams from a predetermined portion of the recording medium and outputting a corresponding reproduction signal. A first measuring unit measures a time period during which an average level of the reproduction signal output from the detector exceeds a reference value, and outputs a first measurement signal. A second measuring unit measures the number of times, at which an interval of pits recorded on the recording medium meets a predetermined modulation rule, by use of the reproduction signal, and outputs a second measurement signal. A discriminating unit discriminates the recording state of the predetermined portion of the recording medium, on the basis of the first and second measurement signals.