Various Controls; Controlling The Laser Activation Timing - Canon imageRUNNER 2545 Series Service Manual

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Technology > Laser Exposure System > Various Controls > Controlling the Laser Activation Timing

Various Controls

■ Controlling the Laser Activation Timing

● Laser ON/OFF Control
Laser ON/OFF control is dependent on the combination of the laser control signal (A/B laser:
CNT1-0/1-1/1-2, C/D laser: CNT0-0/0-1/0-2) from the image PCB.
<A laser/B laser>
Laser control signal
CNT1-2 CNT1-1 CNT1-0
0 1 0
0 1 1
0 0 1
0 1 1
1 1 1 Video signal entry arrowed Video signal entry arrowed
0 1 1
0 0 1
0 1 1
<C laser/D laser>
Laser control signal
CNT1-2 CNT1-1 CNT1-0
0 0 1
0 1 1
0 1 0
0 1 1
1 1 1 Video signal entry arrowed Video signal entry arrowed
0 1 1
0 0 1
0 1 0
2 Technology > Laser Exposure System > Various Controls > Controlling the Laser Activation Timing
Laser status
A Laser B Laser
ON (For APC control) OFF
OFF OFF
OFF ON (For APC control)
OFF OFF
OFF OFF
OFF ON (For APC control)
OFF OFF
Laser status
C Laser D Laser
ON (For APC control) OFF
OFF OFF
OFF ON (For APC control)
OFF OFF
OFF OFF
OFF ON (For APC control)
OFF OFF
J8142
Main Controller PCB
● Main Scanning Synchronous Control
Main scanning synchronous control is operated at synchronous PCB based on BD
synchronous signal.
T-2-22
Based on BD signal that is formed from A laser light detected by BD PCB, BD synchronous
signal for each laser is formed inside image PCB.
Image data written in the line memory is read out by the readable signal (RE_A, RE_B, RE_
C, RE_D) according to the 4 phase differences formed inside the delayPCB based on the BD
synchronous signal (BD_SYNCH) and is sent to the laser driver.
T-2-23
2-31
F-2-51
2-31