Lexmark T652 Service Manual - Page 292

4062-XXX This discharge/no discharge process creates an invisible, electrostatic image on the surface of the drum. This image is called a latent image. Modulated Laser Beam Printhead DRUM Drum Surface Image Laser Beam Drum Surface Voltage Laser Beam Discharge Level Invisible Latent Image 0V Development The toner contained within the PC Cartridge has an electrical property that causes it to adhere to the development roll. The Metering Blade spreads the toner into a very thin layer on the development roll. Friction between the development roll and the CM Blade development roll generates a small electrical charge that is transferred to the toner. The surface of the developer Roll is made up of a thin sheet of conductive material. The HVPS supplies the development Roll with two voltages: a DC voltage and an AC voltage. The DC voltage is used to transfer toner from the development roll to the surface of the drum. The AC voltage agitates the toner on the development roll, making toner transfer easier. The development roll maintains a negative DC electrical potential. Negative charged areas of the drum have a lower electrical potential, or higher relative negative value than the development roll. Discharged areas of the drum have a higher electrical potential, or lower relative negative value, than the development roll. A discharged point on the surface of the drum now appears less negative in relation to the negative charge on the development roll. The toner adhering to the development Roll is always in contact with the drum surface. When a less negative point on the drum (a discharged area) comes in contact with the more negative charged toner on the Magnet 3-80 Service Manual