Ricoh K-C3.5L, Обучение по обслуживанию

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Model K-C3.5L
31
Ricoh Co. Ltd. http://www.ricoh.com/
Slide 31
SBU Board
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The CCD converts the light reflected from the original into an analog
signal.
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Each CCD line has 7,400 pixels, producing a resolution of 600 dpi
(23.6 lines/mm).
CCD
SBU BICU
IPU VCU
8-bit Data
Digital
Processing
IC
A/D
Analog
Processing 1
Analog
Processing 2
O
E
The CCD converts the light reflected from the original into an analog signal. The CCD
line has 7,400 pixels and the resolution is 600 dpi (23.6 lines/mm).
The CCD has two output lines, for odd and even pixels, to the analog processing circuit.
The analog processing circuit performs the following operations on the signals from the
CCD:
1. Z/C (Zero Clamp): Adjusts the black level reference for even pixels to match the odd
pixels.
2. Signal Amplification: The analog signal is amplified by operational amplifiers.
After the above processing, the analog signals are converted to 8-bit signals by the A/D
converter. Each pixel will be assigned a value on a scale of 256 grades. Then, the
digitized image data goes to the BICU board.