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:
Sep. 24, 1996
Filed:
Sep. 13, 1993
Akira Matsueda, Tachikawa, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A clock detection device, for an information recording/reproducing apparatus, which detects whether or not data is present on a recording medium with the edge of a data reproduction clock, which is obtained by reproducing clock information for use in synchronizing with the data recorded on the recording medium to reproduce data on the medium. A plurality of read-clock generating cell groups for generating reading clocks and write-clock generating cell groups for generating writing clocks are disposed in such a manner that the reading clocks and writing clocks have a phase difference of 90 degrees. Among the write-clock generating cell group, reproduction signals having phases which are different from each other by 180 degrees can be obtained from even-numbered cells and odd-numbered cells. By obtaining the sum of the reproduction signals from the odd-numbered cells and that of the reproduction signals from the even-numbered cell, and by subtracting the two sum signals, a writing clock is obtained.