Patent ID: 6042220
Filing Date: 2000-03-28
Classification: B41J,G03G

Abstract:
An image forming device comprising:a carrier for carrying a developer,a counter electrode provided vis-a-vis said carrier,a control electrode provided between said carrier and said counter electrode, said control electrode having a plurality of gates each being composed of a piercing pore and a plurality of electrodes for individually controlling passages of the developer through said gates,wherein the developer is caused to fly from said carrier to said counter electrode by an electric field generated between said carrier and said counter electrode, while the passage of the developer through said gates is controlled by an electric field generated between said carrier and control electrode, so that an image is formed on a surface of a recording medium being transported between said control electrode and said counter electrode, with the developer caused to adhere thereto,electric field control means for controlling the electric field to be generated between said counter electrode and said carrier or between said counter electrode and said control electrode,wherein said electric field control means controls the electric field to be generated so that a strength of the electric field to be generated becomes a level necessary for image formation exclusively in a case where the recording medium covers an effective region of said counter electrode,in other cases, the strength of the electric field to be generated is weakened to one of a level lower than the level necessary for image formation or the electric field to be generated per se is eliminated, andwherein the effective region is a region in said counter electrode facing said carrier and said control electrode where discharge between said counter electrode and said control electrode may possibly occur.