Image Processing By The Cis Unit (Afe) - Canon imageRUNNER ADVANCE C350 series Service Manual

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Technical Explanation > Original Exposure and Feed System > Image Processing > Image Processing by the CIS Unit (AFE)

■ Image Processing by the CIS Unit (AFE)

● Contact Image Sensor (CIS)
The original is exposed to light and read using the contact image sensor (CIS) to read the
image on a line-by-line basis.
In iR-ADV C351/C350, the total of 6 signals are output to the AFE in the CIS. Each signal
consists of the output from 2 sensors (6 channels).
In iR-ADV C250, the total of 4 signals are output to the AFE in the CIS. Each signal consists
of the output from 3 sensors (4 channels).
Image reading line
Copyboard glass
Rod lens array
LED (R/G/B)
Original reading
sensor array
Light guide
LED
Original reading sensor array
2 Technical Explanation > Original Exposure and Feed System > Image Processing > Image Processing by the CIS Unit (AFE)
Light guide
LED (R/G/B)
Scan direction
Rod lens array
Light guide
Component
LED
Light guide
Rod lens array
Original reading sensor
IC (AFE)
Related error code:
E280-0004: Scanner Unit communication error
E280-0005: Scanner Unit communication error
● Original Reading Sensor Drive
The Image Reading Sensor installed in this machine consists of 5,184 light-receiving cells.
The signals which are converted to photoelectricity in the light-receiving part are output to the
Main Controller for each channel of the 12 Image Reading Sensor arrays.
● LED Intensity Adjustment
The machine adjusts the length of time during which the LED turns on for each scan so that
the image scan level of the original reading sensor will be specific level.
Variations in the light intensity between each color and the LED colors are prevented by
changing the LED illumination duration of each color.
Related Service Mode:
• COPIER > ADJUST > CCD > GAIN2CL0 (Gain level adjustment of the CIS)
• COPIER > ADJUST > CCD > GAIN-CL0 (Gain level adjustment of the CIS)
• COPIER > FUNCTION > CCD > DF-WLVL2 (Copyboard scan, Color)
• COPIER > FUNCTION > CCD > DF-WLVL2 (Stream reading scan, Color)
• COPIER > FUNCTION > CCD > CL-AGC (B&W reference level adjustment)
F-2-19
Function
Illuminates the original.
Illuminates the entire image line with the LED light.
Collects the light reflected by the original.
Receives the light that passed through the rod lens array.
IC inside CIS
2-15
T-2-8
2-15