Laser/Scanner System; Outline - Canon LBP-1000 Service Manual

CHAPTER 2
III. LASER/SCANNER SYSTEM
A. Outline
Focusing lens
BD mirror
Mirror
The Engine controller sends the LASER CONTROL signals (CNTRL0, CNTRL1) to the laser driver
in the laser/scanner unit. The video controller sends the VIDEO signals (/VDO, VDO) to the
laser driver via the intermediate PCB.
The laser driver turns ON the laser diode to emit laser beam according to these signals.
The laser beam strikes the scanning mirror, which is rotating at a constant speed, through
the collimator lens and cylindrical lens.
The laser beam reflected from the scanning mirror is brought to a point of focus on the pho-
tosensitive drum by the focusing lens and reflecting mirror.
As the scanning mirror rotates at a constant speed, the laser beam is scanned across the
drum at a constant speed.
The photosensitive drum also rotates at a constant speed allowing the laser beam to form a
latent image on the drum surface.
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Scanning mirror Scanner motor
Figure 2-3-1
Intermediate PCB
Cylindrical lens
Laser driver
Engine
controller
/ACC
/DEC
CNTRL0
CNTRL1
BDI
Video
controller
/VDO
VDO