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:
Dec. 07, 2010
Filed:
Jan. 19, 2007
Kaoru Okamoto, Tokyo, JP;
Jun Sumioka, Kawasaki, JP;
Masakuni Yamamoto, Yamato, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A method of reproducing multilevel information using a light spot. The multilevel information is recorded by defining virtual cells at regular intervals on tracks of an optical information recording medium and varying sizes of information pits in the cells. The method includes the steps of obtaining cell boundary values, each of the cell boundary values being obtained by performing sampling when the center of the light spot reaches a boundary between adjacent cells, calculating cell boundary value metrics on the basis of the cell boundary values and prestored reference values for the cell boundary values, calculating path metrics on the basis of the cell boundary value metrics, selecting a path metric having a minimum value of the path metrics, and reproducing the multilevel information on the basis of the path metric having the minimum value of the path metrics.