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, 1993
Filed:
Jul. 01, 1991
Makoto Hino, Tokyo, JP;
Osamu Takase, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A method and an apparatus for processing an image signal generated in an image reading apparatus comprising a light source for illuminating a document, an optical system, and an optical detector for detecting a light which is reflected at a reading point on the document and passes through the optical system and for outputting an image signal corresponding to an amount of light detected thereby are disclosed. A secondary light source effect function which describes a degree that a light reflected at each point other than the reading point on the document affects the image signal corresponding to the reading point is obtained. The image signal output from the optical detector is corrected based on the secondary light source effect function and an image signal corresponding to each point so that a component corresponding to a light which is reflected at each point other than the reading point and affects the image signal corresponding to the reading point is eliminated from the image signal.