Patent ID: 8878885
Filing Date: 2014-11-04
Classification: G03G

Abstract:
1. An image forming apparatus comprising: an exposure unit configured to perform exposure depending on image data thereby forming a latent image based on the image data on a photoreceptor; a sheet-linear-velocity setting unit configured to variably set, according to a type of a sheet used in printing, a sheet linear velocity indicating speed at which the sheet is conveyed; an image-formation-rate changing unit configured to change, according to the sheet linear velocity set by the sheet-linear-velocity setting unit, an image formation rate indicating a cycle of image formation of the exposure unit; a detecting unit configured to detect a misregistration correction pattern image formed on an image carrier driven at predetermined speed; a first correcting unit configured to correct, when printing is performed with a first sheet linear velocity indicating a reference sheet linear velocity, misregistration according to a result of detection of the misregistration correction pattern image by the detecting unit; and a second correcting unit configured to correct, when the sheet-linear-velocity setting unit sets a second sheet linear velocity indicating a sheet linear velocity other than the first sheet linear velocity, an adjustment amount which has been used in the misregistration correction performed by the first correcting unit, according to a ratio between a first coefficient and a second coefficient, the first coefficient indicating a ratio of an actual image formation rate at the first sheet linear velocity to an ideal image formation rate, and the second coefficient indicating a ratio of an actual image formation rate at the second sheet linear velocity to an ideal image formation rate.