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:
Sep. 27, 2011
Filed:
Dec. 07, 2008
Sadao Fujita, Tokyo, JP;
Sadao Fujita, Tokyo, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
An image forming apparatus which is capable of eliminating influence of in-plane variation contained in secondary-color patches, which is caused by devices, in performing gradation correction. A first toner pattern having a uniform density (of gray) and a second toner pattern having gradation (of gray and black) are formed in a direction orthogonal to a direction of driving an image bearing member. Gradation correction data for converting an input image signal associated with the toner of black is formed, based on density information on the second toner pattern formed by the two toners, and density information on the second toner pattern formed by the toner of gray.