Image Processing - Canon imageRUNNER 2545 Series Service Manual

2
Technology > Original Exposure System > Controls > Image Processing
- Between sheets
The machine does not move CCD.
It reads the original using the position determined at the end or start of a job; however,
if the presence of dust is still detected at the position, the machine will execute image
correction.
0.5mm 0.5mm
A B C
Stream
reading glass
LED
Lens
Service Mode
(Lv1) COPIER > OPTION > IMG-RDR > DFDST-L1
(used to adjust the dust detection level between sheets)
(Lv1) COPIER > OPTION > IMG-RDR > DFDST-L2
(used to adjust the dust detection level at the end of a job)
2 Technology > Original Exposure System > Controls > Image Processing
Platen roller
CCD
F-2-26

■ Image Processing

● Overview
The functions of image processing system's PCB are described below.
- Main controller PCB CCD drive, analog image process, A/D conversion, shading
correction (executed per each job), shading adjustment (executed at
power-on)
- CCD PCB Analog image process, A/D conversion
The machine uses the main controller PCB to process images for every single image line.
Specific functions are as follows.
a. Main controller PCB
- Shading correction
b. CCD PCB (inside CCD unit)
- CCD drive
- CCD output gain correction, offset correction
CCD PCB
CCD(4lines )
Analog image
signal
CCD drive
control
Analog image
A/D
process
conversion
- gain correction
- offset
correction
CCD/AP PCB
Main controller PCB
CCD
ASIC
control
signal
Gain
correction
EEP- ROM
data
CPU
SRAM
Digital
image
Digital image
signal
Shading
signal
correction/
adjustment
F-2-27
2-13
2-13