Patent ID: 7327977

Claim:
An image forming apparatus wherein a plurality of image forming stations are arranged along a moving direction of a transfer medium and form toner images having different colors from each other, an optical sensor detects the toner images which are formed as registration patterns on a surface of the transfer medium at space intervals along the moving direction and outputs a signal, and correction of color registration offset is performed by correcting the registration offset between/among the plural colors based on the output signal from the optical sensor which detects the registration pattern images, the apparatus comprising: a surface condition acquisition unit which acquires a surface condition of the transfer medium based on base information acquired by the optical sensor detecting a surface segment of the transfer medium, the surface segment being located between two adjoining registration pattern images, wherein the surface condition is acquired by detecting the surface segment after the registration patterns are formed on the surface of the transfer medium; and a correction control unit which controls the correction of color registration offset based on the surface condition of the transfer medium acquired by the surface condition acquisition unit.