Patent ID: 11971675
Assignee: RICOH COMPANY, LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. An image forming apparatus, comprising:
a plurality of image bearers;
a plurality of motors to drive to rotate the plurality of image bearers in one-on-one correspondence; and
a reference position detector to detect a rotational position of each of the plurality of image hearers; and
processing circuitry to:
sense a density of a toner image formed on each of the plurality of image bearers;
form a predetermined image pattern and sense, based on a detection result of the reference position detector and a sensing result of the density of the toner image, density unevenness in a rotation cycle of each of the plurality of image bearers and a phase of the density unevenness with respect to a rotational position reference of each of the plurality of image bearers;
calculate, based on the phase of the density unevenness sensed, a target phase of each of the plurality of image bearers;
calculate, based on the rotational position detected by the reference position detector and the target phase calculated, a relative phase difference of each of the plurality of image bearers;
select, as a reference image bearer, an image bearer having a phase correction value that is minimum among the plurality of image bearers, based on a calculation result of the relative phase difference; and
control the rotational position of each of the other image bearers, except for the reference image bearer selected, of the plurality of image bearers with respect to the reference image bearer to the phase correction value, with the plurality of motors being driven.