Dirt Sensor Control - Canon iR4570 Series Service Manual

the sensor level).
Original (A4R)
Original sensor 1
Original sensor 2
Change absent
Change present
F-5-20
The machine uses the following in reference to changes occurring in the sensor output as found in original size
identification processing 1 and original size identification processing 2:
AB-Configuration
Original Original
Original Original
sensor 1 sensor 3
size sensor 2
A3
A4
B4
B5
A4R
B5R
No original
F-5-21

5.3.5 Dirt Sensor Control

5.3.5.1 Outline
iR2270 / iR2870 / iR3570 / iR4570 / iR3530
The machine changes the original read point depending on the presence/absence of dust on the stream reading glass
or the platen roller of the ADF, or it may execute image correction to prevent the dust from showing up in the output.
These operations are carried out only when the ADF is in use and, in addition, is closed:
<Timing of Control>
-at the end of a job
-between sheets (for each reading of a sheet)
-at the start of a job (only when any of the following conditions is true)
1st job after power-on
dust detected at all points of detection at the end of the previous job
dust detection failed to end normally at the end of the previous job (e.g., ADF opened)
Original sensor 3
Original sensor 4
Original
sensor 4
Inch-Configuration
Original Original Original Original
size sensor 1 sensor 3 sensor 5
11"X17"
LTR
LGL
LTR-R
No original
:No original
:change absent
Chapter 5
0006-5929
5-19