In an image forming apparatus having a control electrode including gates for allowing toner to pass through them, an image is formed by allowing or disallowing the toner to jump from the toner support to the opposing electrode whilst controlling the electric field near the control electrode elements...http://www.google.de/patents/US6012803?utm_source=gb-gplus-sharePatent US6012803 - Image forming apparatus forming an image on a recording medium using jumping developer
