Patent ID: 7672602

Claim:
A developing unit that supplies toner from a developing roller to an electrostatic latent image formed on an image carrier, and creates a visual image, the developing unit comprising: a forced consumption unit that causes a forced consumption of a quantity of forcedly consumed toner, the forced consumption occurring when a proportion of a number of pixels used for forming a maximum effective-width of a first electrostatic latent image formed on the image carrier is equal to, or less than, a threshold value, wherein the forced consumption unit determines a first quantity of forcedly consumed toner, the first quantity of forcedly consumed toner corresponding to a difference between a quantity of toner corresponding to a number of pixels of the first electrostatic latent image and a first predetermined quantity of toner, the forced consumption unit causes a correction in the first quantity of forcedly consumed toner based on an average image area ratio for a plurality of images, the corrected first quantity of forcedly consumed toner corresponding to a difference between a quantity of toner corresponding to an average number of pixels for the plurality of images and a second predetermined quantity of toner, and the forced consumption unit adds, to the developing roller, the corrected first quantity of forcedly consumed toner to a quantity of toner to be supplied in forming on the image carrier a next electrostatic latent image.