To suppress occurrence of a defective image when correcting the image width of an image formed on a recording sheet.
When correction unit image regions are watched in a sub scan direction, a correction unit image region on an odd-numbered stage from a top stage and a correction unit image region on an even-numbered stage from the top stage are partially overlapped. Thus, eccentricity P of a pixel that becomes a line deviation in the correction unit image region on the odd-numbered stage from the top stage and eccentricity Q of a pixel that becomes a line deviation in the correction unit image region on the even-numbered stage from the top stage are added, so that each of the eccentricity is complemented as shown by a curve R and the eccentricity of the line deviation in an overall image is relaxed.
MATSUZAKI YOSHIKI
GOTO OSAMU
KATO TAKESHI
ARAI YASUHIRO
KAZAMA TOSHIYUKI
