Canon SmartBase 1270D, Руководство по обслуживанию

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COPYRIGHT © 2002 CANON INC. 2000 2000 2000 2000 CANON SmartBase PC1210D/1230D/1270D REV. 1 MAR. 2002
CHAPTER 4 OPERATION
4-14
3 Laser Exposure System
3.1 Outline
The laser scanner unit consists of the following major components:
• laser unit, which serves as the source of laser beam.
• laser scanner motor, equipped with a 4-face mirror for laser scanning.
• laser driver/BD PCB used to detect laser beam or to control emission of laser beam.
The laser beam generated by the laser unit based on the signals from the DC controller
PCB moves through the collimator lens (inside the laser unit) and the cylindrical lens to
reach a 4-face polygon mirror rotating at a constant speed.
When reflected by the 4-face polygon mirror, the laser beam moves through the imaging
lens, and is bent by the reflecting mirror to reach the photosensitive drum. At this time, the
laser beam also is directed to the BD circuit of the laser driver/BD PCB. (F04-301-01)
As the 4-face polygon mirror rotates at a constant speed, the laser beam scans the surface
of the photosensitive drum at a constant speed, thereby removing charges and forming static
images.