Patent ID: 7453480

Claim:
An image forming apparatus for forming a color image on the basis of arbitrary image information for a color image, the apparatus comprising: (a) an image forming device having an image forming member for forming the color image through a superposition of component color images on the basis of the arbitrary image information; (b) a first detector for detecting a density of the color image formed by the image forming device; (c) a second detector for detecting a position of the color image formed by the image forming device; and (d) a controller for controlling the image forming device on the basis of output signals of the first and second detectors, wherein the controller controls the second detector so as to detect a density of a patch image for a correction of a color density, and corrects a binary coding reference value to be used for detecting positions of mark images for a registration of component color images on the basis of a detected density signal of the patch image outputted from the second detector.