Lexmark M3150

Step 2: Expose
The laser fires a focused beam of light at the surface of the photoconductor and writes an invisible image, called
a latent image. The laser beam only discharges the surface where the beam hits the photoconductor. This
creates a dierence in charge potential between the exposed area and the rest of the photoconductor surface.
Modulated
Laser Beam
0V
DRUM
Drum Surface
Image
Drum Surface
Voltage
Laser Beam
Discharge
Level
Invisible Latent Image
Laser Beam
Printhead
Step 3: Develop
Once the laser exposes the photoconductor, the HVPS sends charge to the developer roll. Because of the
charge dierence between the toner on the developer roller and the electrostatic image created by the laser,
the toner is attracted to areas of the photoconductor surface exposed by the laser.
4514-6xx
Theory of operation
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