Patent ID: 7515857

Claim:
An image forming apparatus for forming a superposed image by writing an electrostatic latent image on an image carrier by scanning-type write means, forming a toner image by developing said electrostatic latent image using toner, and transferring said toner image to an intermediate transfer body, comprising: fluctuation amount detection means for detecting the fluctuation amount of said intermediate transfer body from a reference position in the direction orthogonal to the running direction of said intermediate transfer body (hereinafter referred to as a main scanning direction); start position data correction means for correcting start position data that expresses the write start position in the main scanning direction of said write means in accordance with fluctuation amount data that expresses the fluctuation amount detected by said fluctuation amount detection means; and detection position altering means for altering said predetermined detection position when the amount of change of the fluctuation amount data in adjacent detection positions of said predetermined detection position is larger than a predetermined value.