Patent ID: 7072597

Claim:
An image forming apparatus comprising: image forming means for applying toner to an electrostatic latent image formed on a latent image carrier thereby developing the electrostatic latent image with the toner into a toner image; and density detecting means for detecting a toner density of the toner image formed as a patch image, characterized in that each patch image is formed under each different image forming condition varied stepwise by varying stepwise a density control factor affecting image density and then, the density control factor is optimized based on the detection results of the densities of the patch images given by the density detecting means and on a variation rate of the detection results against the density control value, wherein either one of a value of the density control factor providing a toner density of the patch image substantially equal to a predetermined density target value and a value of the density control factor associated with the variation rate substantially equal to a predetermined effective variation rate is selected as the optimum value thereof according to the state of the apparatus, and wherein out of the value of the density control factor providing the toner density of the patch image substantially equal to the predetermined density target value and the value of the density control factor associated with the variation rate substantially equal to the predetermined effective variation rate, the value providing a lower image density is selected as the optimum value thereof.