Image forming apparatus, developing device, and image forming unit

Abstract

An image forming apparatus includes a latent image bearer configured to bear a latent image and a developing device configured to develop the latent image on the latent image bearer with developer. The developing device includes a plurality of developer bearers configured to bear the developer. The image forming apparatus further includes a rotation position detector configured to detect a rotation position of at least one of the plurality of developer bearers, a common power source configured to apply a developing bias to each of the plurality of developer bearers, and circuitry configured to cause the common power source to periodically vary the developing bias. The circuitry is configured to cause the plurality of developer bearers to rotate in a same rotation period; and vary an output value of the developing bias in a same period as the rotation period based on a detection result by the rotation position detector.

Dependencies are inferred from the claim text.