White Plate Dust Detection Control - Canon iR5055 Series Service Manual

If dust is detected at all 5 points (A, B, C, D, E), the machine will issue an alert in response to the placement of an original in the ADF, thus promoting the user to
clean the points.
Alert Message:
The machine may read the dust, which may show as lines in the output image. Clean the narrow segment of glass indicated in the drawing with a soft cloth moistened
with water (and well wrung).
Press the Close button to reset the alert.
At the start of a job, the machine executes dust detection once again, and will use a point with little or no dust as the read point.
*1: read point at the end of the previous job.
*2: point with little or no dust.
A read reference point (1.0 mm to the left from the center of the platen roller)
B point 1.0 mm to the left from the reference point
C point 0.5 mm to the left from the reference point
D point 0.5 mm to the right for the reference point
E point 1.0 mm to the right from the reference point (center of platen roller)
- Between Sheets (dust correction)
The machine does not move the scanning lamp on account of dust detection.
If dust is detected between sheets, the machine corrects the fact with reference to the pixels on both sides of the area of dust.
SERVICE MODE:
COPIER>OPTION>BODY>DFDST-L1 (level 1)
use it to adjust dust detection level between sheets
COPIER>OPTION>BODY>DFDST-L2 (level 2)
use it to adjust dust detection level at the end of a job

5.3.5.2 White Plate Dust Detection Control

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N
The white plate can collect stray dust inside the reader unit, causing lines in images, and the machine is equipped with a mechanism to check for dust on the plate
and correct it to limit its effects on output images.
1. Timing of Control
(1) Before a Job
(a) white plate dust detection
(b) white plate dust correction
(2) After a Job
(a) white plate dust detection
(b) white plate dust correction
B
At the end of a job
At the start of a job
0.5mm
0.5mm
0.5mm
0.5mm
C A D E
*1
*1
*1
*2
F-5-27
T-5-9
pattern 1
pattern 2
pattern 3
pattern 4
pattern 5
Chapter 5
0015-4410
5-13