Ricoh PRIPORT VT 2000 Series Service Manual page 42

28 February '91
2.4.1 Function
The principle circuit of each pixel in the CCD is shown above. The light
reflected from the original is absorbed in the photodiode and the capacitor
stores the charge corresponding to the light intensity.
The CCD is composed of many such pixel elements in series. The image
signal of each pixel element is stored in the shift register as a charge.
When the SH signal is input, the image signal stored in the shift register, is
output in serial as the OS signal.
SH : Shift Gate
The storage electrode charge in the exposure section is transmitted to the
shift register by the shift gate pulse.
φ1E, φ2E Clock (Phase 1)
This is the transmission clock for analog shift register 2 (even pixels).
φ10, φ20 Clock (Phase 2)
This is the transmission clock for analog shift register 1 (odd pixels).
The shift gate signal transmits the electrical charge in parallel to either
analog shift register 1 or 2 (odd or even pixels). At the same time, the photo
signal storage of the next scan line starts in the exposure section.
The transmission clocks serially shift the electric charge transmitted to the
shift register, which outputs it from the OS (output signal) terminal.
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