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. 09, 2005
Filed:
Feb. 05, 2002
Masahiro Kato, Tokorozawa, JP;
Naoharu Yanagawa, Tokorozawa, JP;
Tatsuhiro Yone, Tokorozawa, JP;
Yuko Muramatsu, Tokorozawa, JP;
Shinji Suzuki, Tokorozawa, JP;
Masahiro Kato, Tokorozawa, JP;
Naoharu Yanagawa, Tokorozawa, JP;
Tatsuhiro Yone, Tokorozawa, JP;
Yuko Muramatsu, Tokorozawa, JP;
Shinji Suzuki, Tokorozawa, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
A pre-pit detecting apparatus which, when a light beam is radiated onto an optical recording medium having a recording surface with pre-pits repeatedly formed between tracks, receives light reflected by the recording surface with first and second light receiving faces, obtains the push-pull signal corresponding to the light receiving signals for the first and second light receiving faces, and binarizes the push-pull signal by using a threshold value to generate a pre-pit detection signal. It is judged which area of a plurality of areas including at least a not-yet-recorded area corresponds to a position of the recording surface where the light beam is radiated is performed to judge. Then the threshold value is set in accordance with the judgement result.