Patent ID: 8582180

Claim:
An image forming apparatus, having an image forming unit, capable of forming a gradation image, the image forming apparatus comprising: a density detection unit detecting a gradation image density of the gradation image formed by the image forming unit; a gradation correction control unit controlling a change of a gradation characteristic according to a detection result of the density detection unit; and a mechanism control unit controlling operation of the gradation correction control unit and controlling a change of a physical characteristic of the image forming unit according to the detection result of the density detection unit, wherein the mechanism control unit includes: a density difference calculation unit calculating a density difference between target image density of an image to be formed by the image forming unit and the image density; and a comparison judging unit comparing the density difference calculated by the density difference calculation unit with a reference value serving as a value in a prescribed range value from the target image density of the image density, and judging execution of the change of the gradation characteristic and the change of the physical characteristic where the density difference is greater than the reference value and judging the execution of the change of the gradation characteristic without changing the physical characteristic where the density difference is smaller than or equal to the reference value, wherein the mechanism control unit arranges the comparison judging unit to be active or inactive, wherein inactivation of the comparison judging unit can switch density correction process to a normal mode, and activation of the comparison judging unit can switch the density correction process to a shortening mode, wherein a switching selection between the normal mode and the shortening mode is switched by a user, wherein the density correction process in the shortening mode is performed in a case where density change corresponds to a predetermined condition, and wherein the density correction process in the shortening mode can be performed immediately after the density correction process in the normal mode is performed.