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:
Jan. 22, 2002
Filed:
Sep. 01, 1999
Yuji Tawaragi, Saitama-ken, JP;
Pioneer Corporation, Tokyo-to, JP;
Abstract
A pre-pit signal detecting apparatus is used in an information recording apparatus for recording record information onto a record medium on which record control information for controlling a recording operation is recorded in advance by forming a pre-pit on the record medium, and detects a pre-pit signal corresponding to the pre-pit when the information recording apparatus records the record information onto the record medium. The pre-pit signal detecting apparatus is provided with: an extracting device, to which a reproduction signal of the record medium is inputted, for extracting and outputting a predetermined signal component, which is used for detecting the pre-pit signal, out of the inputted reproduction signal; an input controlling device for inputting a standard signal, which is set in advance, to the extracting device in place of the reproduction signal before the pre-pit signal is detected and inputting the reproduction signal to the extracting device when the pre-pit signal is detected; a phase difference detecting device for comparing the standard signal outputted by the extracting device with the standard signal inputted by the input controlling device, and for detecting a phase difference generated between the compared standard signals due to an extracting operation of the extracting device before the pre-pit signal is detected; and a pre-pit detecting device for detecting the pre-pit signal on the basis of the extracted predetermined signal component while canceling the detected phase difference.