Canon imageRUNNER ADVANCE 4551i Service Manual page 52

LED Lamp Unit
The LED Lamp Unit emits light from the 2 LED Lamp PCBs (with 36 LED chips for each PCB).
The emitted light exposes the original via the Reflection Plate.
Newly Developed Lens Unit
By using the Lens Unit with 4 lenses combined, downsizing of the Scanner Unit has been achieved.
Reading Sensor
The Reading Sensor reads the image for1 image line.
The Reading Sensor has 4 lines (R, G, B, and B/W). At 600 dpi B&W reading, 1 line (B/W) is used. At color reading, 3 lines (R,
G, and B) are used.
Related Error Code
Light intensity error
• E301-0001: Light intensity is below the reference level at paper front shading.
Shading error
• E302-0001: Error in paper front white shading
• E302-0002: Error in paper front black shading
Lens
mirror
No.4
mirror
No.2
mirror
No.5
Lens
LED (light source)
CCD
Red (R) line
Green (G) line
Blue (B) line
Black & White (B/W) line
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2. Technology
mirror No.3
mirror No.1