Canon Color Bubble Jet BJC-2000 Series, Service Manual

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6. SCANNER CARTRIDGE
6.1 Scanner Cartridge Overview
The scanner cartridge is a replaceable scanner unit that carries a one-line 128 pixel
CCD. The scanner separates each of the three RGB primary colors of the LED by
scanning the same line three times. The color image is output by 8-bit signals, 256
gradation in each RGB color. For a monochrome image, the image is lit with a green
LED and scanned once to output either an 8-bit or 2-bit signal. The maximum
scanning resolution is 360 dpi
✕
360 dpi.
The light source LED within the scanner lights up and illuminates the document on the
platen. The light rays hit the image and, using an imaging lens, the reflected light rays
are converged onto the CCD sensors. The converged light rays are converted to analog
signals by the CCD. After the analog signals have been converted to digital signals by
the scanner controller, the scanned image is processed, and the image data is sent to
the computer via the printer's bi-directional Centronics interface.
Part 4: Technical Reference
4-30
BJC-2000
Scanner Cartridge
Signal Contact
Light Emitting Section
Light Receving Section
Scanner Cartridge
Scanner Controller
Printer
Image Processing
Interface Control
+24V DC
+5V DC
LEDs (R,G,B)
Sensor Control
Scanning
Documents
CCD (Image Sensor)
A/D Converter (10Bit)
Amplifier
Analog Signal Control
Figure 4-24 Scanner Cartridge
Figure 4-25 Block Diagram