3-54 Service Manual
5058-030
Service tips
• If the surface of the charge roller is damaged (for example, if it has a nick or a pit), it will cause
the charge to be uneven on the photoconductor. This will cause a repeating mark on the
printed page. Check the service manual for the repeating marks table.
• If the charge roller is severely damaged, the surface of the photoconductor will not be charged
properly, and heavy amounts of toner will be deposited on the photoconductor. This will cause
the printed page to be saturated with 100% of each color. The imaging basket will need to be
replaced sooner.
Step 2: Exposure
The printhead LED generates a scan line of LED light. Image data received from the RIP card assembly
modulates this scan line, turning it on and off according to image information that is received from the host
computer and software.
Through the use of a series of rotating and stationary mirrors within the printhead, the scan lines are applied on
the negatively charged drum surface. Whenever the print controller sends a command to print a black pixel, the
printhead LED switches on long enough to shine onto the drum at a single pixel point. That point is now
discharged and slightly less negative than the surrounding negative charge. The less negative areas are
considered positive. This discharge/no discharge process creates an invisible, electrostatic image on the
surface of the drum. This image is called a latent image.
LED Light
0V
DRUM
Drum Surface
Image
Drum Surface
Voltage
Laser Beam
Discharge
Level
Invisible Latent Image
Laser Beam
Printhead
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