Patent ID: 8688018
Filing Date: 2014-04-01
Classification: G03G

Abstract:
1. A developing device comprising: a container that accommodates toner serving as developer, the container having an opening facing a latent image holding member that holds a latent image; a toner holding member that is rotatably disposed in the container in such a manner that the toner holding member faces the latent image holding member in a portion thereof facing the opening, the toner holding member being configured to hold toner and transport the toner to a developing region where the toner holding member and the latent image holding member face; a developing electric field forming unit that forms a developing electric field for developing the latent image on the latent image holding member using the toner on the toner holding member in the developing region where the toner holding member and the latent image holding member face; a layer forming unit that is provided for the toner holding member and that forms a toner layer having a predetermined layer thickness on the toner holding member prior to the developing region; an electrode member that is disposed so as to face the toner holding member at a position which is downstream of the developing region and upstream of the layer forming unit in a rotation direction of the toner holding member and that is disposed so as to extend in a direction intersecting the rotation direction of the toner holding member, the electrode member including at least a portion formed of a conductive member and being used to make an electric field act between the conductive member and the toner holding member; and a low-frequency electric field forming unit that forms a low-frequency electric field whose polarity alternately changes periodically at a predetermined low frequency, the low-frequency electric field being made to act on residual toner between the electrode member and the toner holding member, the low-frequency electric field forming unit causing the residual toner on the toner holding member to move to form stripe-shaped projections having a visually observable size in the rotation direction of the toner holding member in accordance with a period of the low-frequency electric field.