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:
Mar. 04, 1997
Filed:
Oct. 24, 1994
Applicant:
Inventor:
Kazuo Ohtani, Kodaira, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06K / ;
U.S. Cl.
CPC ...
382271 ;
Abstract
An image reading apparatus includes an image sensing unit for photoelectrically reading an original image, and outputting an image signal, a converter unit for converting the image signal from the image sensing unit into density data representing density levels of a plurality of steps, a detection unit for detecting frequencies of appearance in units of density levels of the density data from the converter unit, and a correction unit for correcting the density levels expressed by the density data from the converter unit on the basis of the frequencies of appearance detected by the detection unit.