Patent ID: 7630100
Filing Date: 2009-12-08
Classification: H04N

Abstract:
1. A color image forming apparatus which comprises, in correspondence with colors, image forming units, each of which has a photosensitive member as an image carrier, an exposure unit that forms an electrostatic latent image by irradiating the photosensitive member with a light beam modulated according to a color signal, a developing unit that visualizes the electrostatic latent image formed on the photosensitive member by the exposure unit, and a transfer unit that transfers each color image visualized by the developing unit onto a transfer material, the apparatus comprising: a color discrepancy amount storage unit configured to store information of a color discrepancy amount of each of the image forming units, which is measured in advance; a first color discrepancy correcting unit configured to perform color discrepancy correction in a pixel unit by performing coordinate conversion of bitmap data to be printed based on the information of the color discrepancy amount stored in said color discrepancy amount storage unit; and a second color discrepancy correcting unit configured to perform color discrepancy correction in less than a pixel unit by performing tone correction of the bitmap data corrected by said first color discrepancy correcting unit based on the information of the color discrepancy amount stored in said color discrepancy amount storage unit.