Patent ID: 6442355
Filing Date: 2002-08-27
Classification: G03G

Abstract:
A developer density controlling apparatus comprising:first detecting means for detecting information corresponding to a density of a toner in a developer in a developer container; second detecting means for detecting information corresponding to a density of a toner image; and control means for controlling a replenishing amount of the toner with which said developer container is replenished on the basis of an output of said first detecting means and a target value; wherein said apparatus includes a first mode for changing the target value in accordance with the output of said first detecting means and an output of said second detecting means, and a second mode for not changing the target value in accordance with the output of said first detecting means and the output of said second detecting means, wherein a number of an image forming operations effected between a detecting operation and next detecting operation, which are effected by said second detecting means, is larger in the second mode than in the first mode.