Patent ID: 6123418
Filing Date: 2000-09-26
Classification: B41J,G03G

Abstract:
An image forming apparatus comprising:a supporting means for supporting the developer;an opposing electrode disposed facing the supporting means;a control electrode disposed between the supporting means and the opposing electrode and having a plurality of gates which form passage for the developer particles; anda controlling means which generates a predetermined potential difference between the supporting means and the opposing electrode and, by varying a potential applied to the control electrode, controls passage of the gates for the developer so as to form an image on a recording medium arranged between the control electrode and the opposing electrode, wherein the controlling means performs control in such a manner that a gate-facing area of the developer on the supporting means from which the developer jumps toward the gate becomes greater than an area of a pixel dot resultantly formed on the recording medium, and a duration t within which the potential causing the developer to pass through the gate is applied to the control electrode satisfies a relation t<T, where T is the time duration with which, if an electric field equivalent to or approximately equivalent to that generated by the potential being applied to the control electrode causes the developer to jump in a system where no control electrode is present between the supporting means and opposing electrode, the resultantly formed pixel dot of the developer will have the maximum density.