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:
Jan. 15, 1991
Filed:
Aug. 10, 1989
Kazuo Horikawa, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
Shading is eliminated in an image read-out apparatus wherein a light beam is deflected by a rotating polygon mirror which has a plurality of reflecting surfaces, a surface which has an image recorded thereon is two-dimensionally scanned with the deflected light beam, and light which is emitted by the scanned surface and which carries information about the image is detected and converted into an image signal by a photoelectric read-out device. The shading elimination method comprises the steps of storing the characteristics of the shading with respect to the respective reflecting surfaces, the shading being caused by nonuniformity in the intensity of the light beam, nonuniformity in the speed at which the surface is scanned with the light beam, nonuniformity in how the photoelectric read-out device, detects light which is emitted by said surface, or the like. Fluctuations in the image signal, which are caused by the shading, are eliminated with respect to the respective reflecting surfaces on the basis of the shading characteristics which correspond to the respective reflecting surfaces.