Oki C7200 Service Manual - Page 33

Service Guide - C7000 Series Chapter 2 Operation Page: 12 (1) Electrophotographic processes (1) Electrophotographic processes - The following is the outline of electrophotograhic process: (1) Charging - DC voltage is applied to the charging roller and the surface of the OPC drum is negatively and evenly charged. (2) Exposure - The LED head, under image signals, emits light to the negatively charged surface of the OPC drum. The radiated portions of the drum surface attenuate in negative charge according to the intensity of the light and, based on the surface potentials, a latent electrostatic image is formed on the drum surface. (3) Development - Negatively charged toner contacts the OPC drum and by electrostatic force adheres to the latent electrostatic image to form a clear image on the drum surface. (4) Transfer - Placed on the surface of the OPC drum, paper is positively, or opposite to the polarity of the toner, charged by the transfer roller on its back to transfer the toner image to the paper. (5) Cleaning - The cleaning blade removes residual toner from the OPC drum after the transfer. (6) Fusing - The toner image on the paper is fused into place through the application of heat and pressure to it. Copyright 1999, Okidata, Division of OKI America, Inc. All rights reserved.