Canon 1730, Service Manual

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Technical Explanation > Original Exposure and Feed System > Controls > Contact Image Sensor (CIS)
Technical Explanation > Original Exposure and Feed System > Controls > Contact Image Sensor (CIS)
1) Forward Movement during Image Scan
During image scanning, the reader controller PCB controls the reader motor (M10) to
control the contact image sensor (CIS) operation.
Start
position
Acceleration
Leading edge
of original
Constant speed
Trailing edge
of original
Deceleration
Stop
Movement
speed
Movement distance
[1] [2] [3] [4]
[1] Acceleration area: The motor accelerates to the speed specified
for each mode.
[2] Runup area: A margin to stabilize the speed.
[3] Image read area: The image is read at a constant speed.
[4] Deceleration area: Upon detection of the trailing edge,
the motor decelerates rapidly and stops.
2) Backward Movement after Image Scan
After image scan, the carriage moves back to the contact image sensor (CIS) shading
position at the constant speed (160 mm/sec).
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Contact Image Sensor (CIS)
● Outline
The original is exposed to light and read using the contact image sensor (CIS) to read the
image on a line-by-line basis.
Light guide
LED (R/G/B)
Original reading
sensor array
Rod lens array
Image reading line
Copyboard glass
LED (R/G/B)
Scan direction
Light guide
Light guide
LED
CCD
Rod lens array
Component Function
LED Illuminates the original.
Light guide Illuminates the entire image line with the LED light.
Rod lens array Collects the light reflected by the original.
Original reading sensor array Receives the light that passed through the rod lens array.
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