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:
Apr. 11, 2006
Filed:
Apr. 07, 2003
Akihiko Shimizu, Kanagawa, JP;
Akihiko Shimizu, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A multi-value data recording and reproducing device is provided that can accurately eliminate interference among codes through waveform equalization when reproducing information from a reproduction signal having levels multi-valued through modulation of the areas of recording marks on an optical information recording medium. This multi-value data recording and reproducing device is embodied by a multi-value data detecting circuit that varies the sizes of the recording marks in accordance with multi-value data (0, 1, 2, . . . , (m−1): m being an integer of 3 or greater) on the optical information recording medium, and detects the multi-value data through predetermined signal processing on signals obtained by scanning the recording marks with an optical spot. This multi-value data detecting circuit includes: a predictor that predictively determines the multi-value data; a delay unit that delays the predetermined signal processing by the period of time required for the predictive determination by the predictor; and a determiner that determines the multi-value data through waveform equalization based on predictive data that are the predictive determination results from the predictor.