Canon LBP-800, Руководство по обслуживанию

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III. LASER/SCANNER SYSTEM
A. Outline
The microcomputer (CPU:201) on the engine controller sends the LASER CONTROL signals
(CNT0, CNT1) to the laser driver (IC801) on the laser driver PCB. The VIDEO signals (/VDO,
VDO) from the interface controller are sent to the laser driver (IC801) on the laser driver PCB
through the engine controller.
The laser driver (IC801) emits the laser beam according to these signals sent from the engine
controller and interface controller.
The laser beam emitted form the laser diode passes though collimator lens and cylindrical
lens, and then strikes the four-faced scanning mirror rotating at a constant speed.
The beam reflected from the four-faced scanning mirror passes through focusing lens and is
reflected onto the photosensitive drum.
When the photosensitive drum rotates, and at the same time, the laser beam scans across its
surface at a constant speed, the laser beam forms an latent image on the drum surface.
Figure 2-3-1
CHAPTER 2
2 - 16
Cylindrical
lens
Laser
unit
Four-faced
scanning
mirror
Scanner motor
Focusing lens
BD sensor
Reflecting mirror
Photosensitive drum
Interface controller PCB
Engine controller PCB
/BDI
/DEC
/ACC
/BD /VDO,VDO
CNT0
CNT1