Patent ID: 8249474

Claim:
An image forming apparatus comprising: a latent image carrier; a developing device to supply toner to the latent image carrier and develop a latent image formed on a surface of the latent image carrier with the toner to form a toner image; a transfer device to either directly transfer the toner image formed on the surface of the latent image carrier onto a recording medium, or to primarily transfer the toner image from the latent image carrier onto an intermediate transfer body and then secondarily transfer the toner image from the intermediate transfer body onto a recording medium; a post-transfer imaging unit to photograph, at magnification, the surface of the latent image carrier after transfer of the toner image from the latent image carrier onto either the recording medium or the intermediate transfer body, or a surface of the intermediate transfer body after transfer of the toner image from the intermediate transfer body onto the recording medium; and a control unit to control one or more image forming conditions based on a quantified value for residual toner of a detection pattern obtained by forming the detection pattern and photographing a portion of the surface of the latent image carrier or the intermediate transfer body on which the detection pattern is formed after transfer of the detection pattern from the latent image carrier onto the recording medium or the intermediate transfer body or after transfer of the detection pattern from the intermediate transfer body onto the recording medium using the post-transfer imaging unit, the quantified value representing the amount of residual toner of the detection pattern attached to either the surface of the latent image carrier or the intermediate transfer body based on a photographed image of the detection pattern, wherein the control unit divides the image photographed by the post-transfer imaging unit into multiple ranges, classifies each of the multiple ranges into a toner portion and a non-toner portion, and quantifies the residual toner of the detection pattern based on a size of the ranges classified as the toner portion.