| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus that can increase the amount of discharge current without increasing a peak-to-peak voltage Vpp to provide suitable charging.SOLUTION: An image forming apparatus applies, to a contact charging member, a charging bias Bc that takes a rectangular waveform before reaching a discharge start voltage Vth and takes a triangular waveform during the half period after reaching the discharge start voltage Vth, so as to charge the surface of a photoreceptor. The discharge time Tc of the charging bias Bc is longer than the discharge time Ts of a sine wave bias Bs. The image forming apparatus extends the discharge time without increasing the minimum voltage Vmin of the charging bias Bc, so as to avoid an increase in cost of a power source device. |
