Canon IMAGERUNNER ADVANCE C5030, Service Manual, Page: 74 / 1455

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Technology■>■Laser■Exposure■System■>■Various■Controls■>■BD■correction■control
Technology■>■Laser■Exposure■System■>■Various■Controls■>■BD■correction■control
■
■
BD■correction■control
■ ● Purpose
This■is■to■correct■the■displacement■of■writing■start■position■of■each■color■laser■due■to■the■angle■
variation■of■scanner■mirror■facet.
■ ●
Execution timing
At■power-ON,■per■printing
■ ●
Execution time
Within■approx.■0.5s■or■less
■ ●
Control detail
1)■DC■Controller■measures■the■BD■interval■after■the■constant-speed■rotation■control■of■
Scanner■Motor■is■completed.
2)■DC■Controller■calculates■the■correction■value■according■to■the■gap■of■BD■interval.
3)■Based■on■the■foregoing■correction■value,■image■writing■position■is■corrected.
BD1 BD2 BD3 BD4
BD1 BD2
α
α
BD3 BD4
BD1 BD2 BD3 BD4
VDO VDO VDO VDO
START
END
Scanner motor
control finish
(Constant-speed
rotation detection)
BD interval
measurement
Writing start correction
value calculation
Writing start position
correction
Narrow interval
Constant interval
Constant interval
Constant interval
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