Epson AcuLaser C2600 Service Manual page 89

EPSON AcuLaser C2600/2600
2.1.3.2 Exposure
At the "Exposure" process, a laser beam is applied to the negatively charged surface of
the drum to form an invisible electrostatic latent image onto the drum.
PRINCIPLE OF EXPOSURE
The laser beam is emitted from a laser diode in the ROS ASSY, and directed by
the polygon mirror, fixed mirror and lens of the Scanner Assy in the ROS ASSY.
A single laser beam is output from the laser diode.
The laser beam is irradiated according to the print data (image data) from the
printer controller. The laser beam is output only when a pixel data (minute dot
composing the print data) exists. (On parts to be developed by toner, the laser
diode turns ON, and on parts not to be developed, the laser diode turns OFF.) The
drum surface irradiated by the laser beam becomes a conductor, the negative
charge on the drum flows to the positive side, and the potential on the surface of
the drum is reduced in the result. The section of the drum surface where the
potential has reduced becomes the electrostatic latent image.
Drum Surface
Operating Principle
(Laser Beam)
Electrostatic
Latent Image
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Drum Surface Potential
(Laser Beam)
<Formation of Electrostatic Latent Image on Drum>
Photoconductor
Electric Conductor
Figure 2-5. Principle of Exposure
Print Process
Photosensitive Material
Conductor
Drum
(Laser Beam)
LSU
Laser Beam
Electrostatic Latent Image
Revision B
Negative Charge
Positive Charge
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