Patent ID: 6999690

Claim:
An image forming apparatus comprising: an image bearing member; charging means, to which a voltage including an AC voltage is applied, for charging the image bearing member; control means for controlling a peak-to-peak voltage of the AC voltage; developing means for developing an electrostatic latent image formed on the image bearing member with a developer; and residual charge eliminating means for conducting charge elimination on the image bearing member, wherein the control means controls the peak-to-peak voltage of the AC voltage which is applied to the charging means during an image forming period, on the basis of both an AC current flowing when applying the AC voltage having a voltage level of the peak-to-peak voltage that is less than twice the discharge start voltage Vth of the image bearing member to the charging means during a non-image forming period and another AC current flowing when applying the AC voltage having a voltage level of the peak-to-peak voltage that is equal to or more than twice the discharge start voltage Vth of the image bearing member to the charging means during a non-image forming period, and wherein the residual charge eliminating means conducts charge elimination on an area on the image bearing member that passes through a charging position of the charging means when applying the AC voltage having a voltage level of the peak-to-peak voltage that is less than twice the discharge start voltage Vth of the image bearing member to the charging means.