Epson EPL-N3000 Service Manual page 35

EPSON EPL-N3000/AcuLaser M4000N
FUSER ASSY
to Duplex
Pressure Roll
Drum
IMAGING CARTRIDGE
BTR ASSY
Mag.Roll
from Duplex
from Option Feeder
Figure 2-3. Major Components Related to Paper Transport
In the exposure step, the drum surface negatively charged in the previous charging step
is scanned by thin laser beams. The laser, which the Laser Diode of the ROS (Raster
Output Scanner) radiates, scans from one end to the other of the drum via the rotating
Polygon Mirror (12 planes) and lens.
Emission of the laser beam is adjusted according to the Video signal transmitted from
the Main Board Assy.
Operating Principles
Heat Roll
ROS ASSY
JG6103AA
The laser beam striking the Drum surface excites the electrons moving toward the
conductor and consequently generates "electron ⇔ hole" pairs inside the
photoconductive layer. Electrons, attracted by the electric field, move toward the inner
metal portion of the drum and flow in there. Holes move toward the external surface of
the photoconductive layer, thus reducing negative charges there. The areas of the lower
negative charge level form the latent print image.
In the next process, toner is attracted to the electrostatic latent image, thus a visible
toner image is generated.
Attracted by positive charge supplied from the BTR (Bias Transfer Roll), the toner
image is transferred from the surface of the Drum onto the paper. Then the Drum
proceeds to the separation process and cleaning process.
Figure 2-4. Electrostatic Latent Image Generated on the Drum
Overview
Revision C
35
Confidential