Laser On/Off Control; Purpose; Execution Timing; Control Description - Canon imageRUNNER ADVANCE C3325 Series Service Manual

2
Technical Explanation > Laser Exposure System > Controls > Laser ON/OFF control
Controls
■ Overview
Item

Laser ON/OFF control

Turns the laser beam ON and OFF according to the combination
of laser control signals.
Horizontal scanning Aligns the write start position in the horizontal scanning direction.
synchronous control
Vertical scanning synchronous Aligns the write start position in the vertical scanning direction.
control
Image mask control Prevents soiling of the Secondary Transfer Outer Roller.
Laser scanner motor control Rotates the Polygon Mirror at a specified speed.
APC(Auto Power Control) control Ensures constant laser beam light intensity for each line.
BD correction control Corrects displacement of BD timing for the displacement of the
Polygon Mirror angle.
DC Controller
PCB (UN04)
Laser ON/OFF control
Horizontal scanning
synchronous control
Vertical scanning
synchronous control
Main
Controller PCB
Image mask control
(UN05)
Laser scanner motor control
APC control
BD correction control
2 Technical Explanation > Laser Exposure System > Controls > Laser ON/OFF control
Operation description
T-2-13
Y/M/
Laser Driver PCB
(UN08)
C/Bk
Laser Driver PCB
(UN09)
Laser Scanner Motor
Laser Scanner Unit
F-2-35
■ Laser ON/OFF control
● Purpose
Turns the laser beam ON and OFF according to the combination of laser control signals.
● Execution timing
After Power-On
● Control description
The DC Controller switches between four modes (Forced OFF mode, APC mode, Print mode,
and Standby mode) by laser control signals.
DC Controller
PCB (UN04)
Y/M/C/Bk
Laser Driver
CPU
PCB (UN08)
ASIC
Laser ON
/OFF signal
Video signal
APC signal
ASIC
Main Controller C/Bk
PCB(UN05) Laser Driver
PCB (UN09)
Mode Laser Status
Forced OFF mode OFF Clears the light intensity setting determined by the APC.
APC mode ON Adjusts the laser light intensity.
Print mode ON/OFF Emits the laser according to the video signal.
Standby mode OFF The machine is in standby mode.
Print Image formation
instruction ready timing
PSTBY PINTR
At 1st line (APC)
LaserA
Mode Standby
APC mode APC mode / Print mode
name mode
2-27
Laser Scanner
Motor
Laser
Beam
F-2-36
Remarks
T-2-14
PRINT LSTR PSTBY
Forcible Standby
OFF mode mode
F-2-37
2-27