Service Guide OKIFAX 5750/5950Chapter A Board DescriptionsPage: 284A3.1.12 Electrophotographic Process(1) Electrophotographic processThe electrophotographic process is outlined below.1 ChargingThe surface of the image drum is charged negatively and uniformly by applying the DC voltage to the charge roller.2 ExposureLight emitted from the LED head irradiates the negatively charged surface of the image drum. The surface potential of the irradiated surface attenuates to formthe electrostatic latent image corresponding to the image signal.3 Development and residual toner recoveryThe negatively charged toner is brought into contact with the Image drum, adhering to the electrostatic latent image on the image drum by static electricity. Thisadhesion causes the electrostatic latent image to change to a visible image.At the same time, the residual toner on the image drum is attracted to the developing roller by static electricity.4 TransferWhen paper is placed over the image drum surface, the positive charge which is opposite in polarity to that of the toner, is applied to the reverse side by thetransfer roller. The toner is attracted by the positive charge and is transferred onto the paper. This results in the transfer of the toner image formed on the imagedrum onto the paper.5 CleaningThe cleaning roller temporarily attracts the residual toner on the transferred image drum with static electricity, then returns the toner to the image drum.6 FusingThe transferred unfused toner image is fused to a sheet of paper by applying heat and pressure to the image.An electrophotographic process timing chart is shown in Figure 2-5.
