Image Processing System (Ir7200); Outline - Canon iR8500 Service Manual

CHAPTER 2 NEW FUNCTIONS

5 Image Processing System (iR7200)

5.1 Outline

The major functions of the image processing system are as follows:
• CCD (image sensor)
Number of lines: 1
Number of pixels: 7450
Size of pixel: 4.7 × 4.7 µm
• Shading Correction
Shading adjustment: executed in service mode
Shading correction: executed for each copy
• Auto Density Adjustment (AE)
Executed for each line in main scanning direction.
The image processing system consists of the following functional blocks:
Analog image processing block
CCD
Analog
image
processing
CCD/AP PCB
Each of the PCBs used in the image processing system has the following functions:
[1] CCD/AP PCB: Drives the CCD, performs analog image processing, performs A/D
conversion.
[2] Reader controller PCB: Performs shading correction, performs auto density adjustment
(AE).
2-86
Digital image processing block
A/D
conversion
F02-501-01
COPYRIGHT© 2001 CANON INC.
Reader controller PCB
Shading processing
Auto density
correction (AE)
2000 2000 2000 2000
Controller unit
CANON iR8500/7200 REV.1 AUG. 2001