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:
Oct. 05, 2010
Filed:
Mar. 08, 2010
Jun Sumioka, Kawasaki, JP;
Masakuni Yamamoto, Yamato, JP;
Kaoru Okamoto, Ohta-ku, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical information reproducing method of reproducing multivalued information recorded on a track of an optical information medium having a recording/reproducing region, which has virtual cells arranged thereon at regular spacings, the multivalued information being recorded thereon by changing a length of an information pit in a track direction or an area of the information pit in a cell with the use of a light spot, and the multivalued information being reproduced by detecting the level of a multistage reproduced signal from the information pit. The method includes sampling reproduced signals in the multivalued information recorded in two continuous cells with an M-value (M<N), which are arranged at each of the plurality of cells recorded by an N-value (N≧3) on the track, and detecting an intercell value, and obtaining a phase error for producing a reproduction clock on the basis of the detected intercell value, a previously derived ideal value of the intercell value, and a previously derived gradient of the reproduced signal in the vicinity of the ideal value of the cell center value.