Patent ID: 8073347
Filing Date: 2011-12-06
Classification: G03G

Abstract:
1. An image forming apparatus comprising: an image holder; a latent image forming unit that forms an electrostatic latent image containing an image portion and a background portion on the image holder; a developing unit that develops the electrostatic latent image formed on the image holder with toner, the developing unit including a developer holder that is disposed to face the image holder and holds developer containing the toner and carrier, and a developer container that contains the developer to be supplied to the developer holder; a replenishing unit that replenishes new developer to the developing unit; a discharge unit that discharges from the developing unit the developer contained in the developing unit; a calculation unit that calculates an image area coverage of a toner image formed on the image holder; an obtaining unit that obtains a potential difference between the developer holder and the image portion on the image holder; and a controller that increases a discharge amount of the developer to be discharged from the developing unit by the discharge unit when the image area coverage calculated by the calculation unit is smaller than a predetermined reference image area coverage, and the potential difference obtained by the obtaining unit is larger than a predetermined reference potential difference.