Epson AcuLaser C1100 Service Manual page 78

EPSON AcuLaser C1100
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.
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.
Mirror SOS
PWBA LD
Lens COL
Lens CYL
Scanner Assy
Polygon Mirror
Figure 2-4. Path followed by the Laser Beam
OPERATING PRINCIPLES
Drum
Window
Mirror
SOS Sensor
PWBA SOS
Lens L1
Leg_Sec06_008FA
Print Process
Figure 2-5. Exposure Process
Revision B
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