Construction; Outline Of The Laser Exposure System - Canon ImageRunner iR8500 Series Service Manual

7.1 Construction

7.1.1 Outline of the Laser Exposure System

iR105i/iR105+ / iR9070
The laser exposure system consists of a laser unit (source of laser beams) and a polygon mirror. It scans the photosensitive drum (main scanning direction)
to create a latent static image. It is a twin-laser mechanism (laser A, laser B).
Component
Laser semi-conductor
Laser scanner motor (M4)
Polygon mirror
BD mirror/BD PCB
Laser driver PCB
Scanner motor driver PCB

7.1.2 Outline of the Laser Exposure System

/ iR85+ / iR8070
The laser exposure system consists of a laser unit (source of laser beams) and a polygon mirror. It scans the photosensitive drum (main scanning direction)
to create a latent static image. It is a twin-laser mechanism (laser A, laser B).
Laser B
8-face mirror
Laser scanner motor
BD PCB
BD mirror
Description
Visible laser light (wave length: 675 nm; output: 7 mW),
twin-laser exposure
DC motor, 2-speed control; rotation speed: 44000 rpm
8-face
Used to detect laser beams.
Used to control laser activation.
Used to control the rotation of the laser scanner motor.
Laser A
80µm
Laser driver PCB
Laser unit
Collimating lens
Laser A
Laser B
18 pixels (760 µm)
F-7-1
T-7-1
Laser mirror
Photosensitive drum
Chapter 7
0007-0533
0008-7437
7-1