Canon Vizcam 1000, Service Manual

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3. OPERATION AND TIMING
COPYRIGHT © 2001 CANON INC. CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
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IV. LASER EXPOSURE SYSTEM
A. Outline
The laser exposure system consists of a laser unit, which is the source of laser beams, a laser scanning
unit, which performs laser scanning (main scanning direction) using a polygon (8-facet) mirror, and a BD
detection PCB, which generates sync signals for scanning direction.
Figure 3-401
The video signals (for M in Figure 3-401), which is synchronized for main and sub scanning directions by
the video controller, are converted by the laser driver into laser drive signals that represent the level of the
signals. The laser beam is generated by the laser unit using this laser drive signal. The laser beam comes to
have scanning characteristics in a specific direction because of the polygon mirror, which rotates at a high
speed. The laser beam hits and scans the negatively charged photosensitive drum (Figure 3-401) to form a
static latent image on the photosensitive drum.
Polygon mirror
BD detection PCB
Laser unit for M
DC controller PCB
Video controller PCB
Laser driver PCB
Video signals
BD signal
Motor driver PCB