Image forming apparatus including rotatable magnetic field generating means and control means for controlling image tone

摘要

An image forming apparatus capable of forming a tone image including an image bearing member; electrically independent plural electrodes; a rotatable magnetic field generator having plural magnetic poles to supply magnetic toner particles to a region between the image bearing member and the recording electrodes; a detector for detecting the positions of the magnetic poles of the magnetic field generator; and a controller, responsive to an output of the detector, for controlling application timing of a voltage on the recording electrodes.