Patent ID: 7702265

Claim:
A developing unit for transferring toner onto a latent image on an image carrier, comprising: a toner carrier configured to bear and transport the toner to a developing area facing the image carrier, and including a plurality of electrodes disposed along a surface thereof and insulated from each other; an electric field generator configured to apply a periodic voltage to the plurality of electrodes of the toner carrier to generate an electric field on the toner carrier surface; a separating force applicator configured to apply a separating force to separate the toner on the toner carrier from the surface thereof outside the developing area, wherein the separating force applicator is disposed separately from the electric field generator; and a layer thickness regulator configured to regulate a thickness of the toner on the toner carrier surface before the toner is transported to the developing area, wherein the separating force applicator applies the separating force to the toner on the toner carrier surface through the layer thickness regulator.