Laser Exposure System; Outline - Canon iR8500 Service Manual

CHAPTER 2 NEW FUNCTIONS

6 Laser Exposure System

6.1 Outline

The laser exposure system consists of a laser unit (source of the laser beam) and a poly-
gon mirror, and it scans the photosensitive drum by running a beam in main scanning direc-
tion to create static latent image.
A pair of lasers (laser A, laser B) is used for scanning (twin laser exposure); F02-601-01
and T02-601-01 shows the basic construction of the laser exposure system.
8-facet mirror
Laser scanner motor
BD PCB
2-100
80µm
Laser B
BD mirror
Laser B
F02-601-01
COPYRIGHT© 2001 CANON INC.
Laser A
Laser driver PCB
Laser unit
Collimating lens
Photosensitive drum
Laser A
18 pixels (760 µm)
2000 2000 2000 2000 CANON iR8500/7200 REV.1 AUG. 2001
Laser mirror