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:
Apr. 25, 2000
Filed:
May. 09, 1997
Kazumi Kuwata, Tokyo, JP;
Kouji Hayashi, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An image forming apparatus according to the present invention comprises a scanner for optically scanning and reading a draft image, an image processing circuit for converting input image signals from this scanner to output image signals by referring to an image signal conversion table and outputting the converted signals, a laser optical system for writing image information on a photosensitive drum in response to the output image signals, developing units for forming images with toner, an image signal generating means for generating a plurality of gradation patterns, and a CPU which prepares and selectors an image signal conversion table according to read signals for gradation patterns read by the scanner; wherein a read signal for a gradation pattern comprises a plurality of signals with different spectral sensitivity respectively, and said image forming apparatus has a RAM to store calibration factors for the plurality of factors with different spectral sensitivity respectively and calibrates read signals according to a calibration factor from the RAM.