Canon iR7086, Service Manual

Page: 207 / 735

Chapter 5
5-21
F-5-49
2. Digital Image Processing
- shading correction
F-5-50
5.3.6.3 CCD Drive
0011-2249
iR7105 / iR7095
1. CCD
The CCD used in the machine is a 1-line linear image sensor.
- Number of pixels: 7400
- Size of a pixel: 4.7 x 4.7 ym
2. CCD Drive
The signals converted by the light-receiving block are sent out in 2 analog video signal channels (even-numbered pixels, odd-numbered pixels).
F-5-51
5.3.6.4 CCD Drive
0011-2256
iR7086
1. CCD
The CCD used in the machine is a 1-line linear image sensor.
- Number of pixels: 7450
- Size of a pixel: 4.7 x 4.7 ym
2. CCD Drive
The signals converted by the light-receiving block are sent out in 2 analog video signal channels (even-numbered pixels, odd-numbered pixels).
CCD (1 line each for R, G, and B)
Analog image
signal
Analog image
process
- gain correction
- offset correction
A/D
conversion
CCD drive
control
A12V
A5V
J101 J204
J204
J102
J205
CCD control
signal
Gain correction
data
Digital image
signal
Reader
controller
PCB
Odd-numbered
pixel
Odd-numbered
pixels
Even-numbered
pixels
CCD/AP circuit
10
Even-numbered
pixel
Gain correction
data
EEP-ROM
SRAM
CPU
Shading correction
Digital image
signal
CCD/AP
PCB
Reader controller PCB
10
Digital image
signal
8
Target
value
J101
J102
J204
J205
J203
Direction of charge transfer Direction of charge transfer
Direction of charge transfer Direction of charge transfer
3700 3699 3698 3697 3701 3702 3703 3704 7400 7399 7398 7397 4 3 2 1
Output
unit A
Output
unit B
Output
unit C
Output
unit D
CCD
shift
pulse
Transfer unit A
Clock pulse B Clock pulse D
Clock pulse A Clock pulse C
Transfer unit B
Transfer unit C
Transfer unit D
Light-
receiving
unit