Toshiba e-STUDIO163, Service Manual

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8
© 2005 - 2008 TOSHIBA TEC CORPORATION All rights reserved e-STUDIO163/203
LASER OPTICAL UNIT
8 - 3
Cautions:
- Avoid expose to laser beam during service. This equipment uses a laser diode. Be sure not to
expose your eyes to the laser beam. Do not insert reflecting parts or tools such as a screwdriver
on the laser beam path. Remove all reflecting metals such as watches, rings, etc. before starting
service.
- When servicing the equipment with the power turned ON, be sure not to touch live sections and
rotating/operating sections. Avoid exposing your eyes to laser beam.
- During servicing, be sure to check the rating plate and cautionary labels such as "Unplug the
power cable during service", "CAUTION. HOT", "CAUTION. HIGH VOLTAGE", "CAUTION.
LASER BEAM", etc. to see if there is any dirt on their surface and if they are properly stuck to the
equipment.
2) Polygonal motor unit
This unit consists of the polygonal motor (M4) and polygonal mirror.
a. Polygonal motor (M4)
This motor rotates the polygonal mirror in high
speed.
The DC motor controls the rotation speed of
the mirror motor as follows:
During ready: 0 rpm (No rotation)
During printing
: 21,521.147 rpm (600dpi)
Fig. 8-4
b. Polygonal mirror
One laser beam emitted from the laser diode
is reflected by this mirror. As the polygonal
mirror is rotated by the polygonal motor (M4),
the reflected laser light moves in sync with the
rotation. The direction of the movement is the
primary scanning direction of the image. One
scan is performed on one plane of the polygo-
nal mirror.
As the polygonal mirror has six planes, six
scans are performed in one rotation of the
polygonal mirror.
One scan is completed by completion of steps (A)
to (C). One scan is performed on one plane of the
polygonalmirror. Six scans can be made with one
rotation of the polygonal mirror.
(A)
Drum
Laser beam
(B)
Drum
Laser beam
(C)
Drum
Laser beam