FujiFilm CR-IR341, Service Manual

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CR-IR341 Service Manual 009-051-04
05.31.99 FM2460 MD - 48
MD - 48
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ONTENTS
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SCN08A Board
The SCN08A board, which is located between the MTH board and scanning optics/scanner
unit, controls each I/O of the scanning optics/scanner unit in accordance with an instruction
from the MTH board.
Polygon driver/laser/HV control is performed so that a start-point detection signal detected
by the SYN08A board and a leading-edge detection signal detected by the SED08A board
are acquired as sync signals to control the image acquisition timing. Furthermore, as its self-
diagnostic function, image quasi-read control is implemented to generate a quasi-read LED
output voltage.
For image acquisition, an analog image signal is inputted from the PMT08A board (log amp
board), and after shading correction and filtering, it is analog-to-digital (A/D) converted for
output to the IMG08A board (image processing board) as digital image data.
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Image signal acquisition
A block diagram, from input of an analog signal from the PMT08A board (log amp board) to
A/D conversion for output to the IMG08A board (image processing board), is illustrated
below. The digital image data acquired is transferred to the IMG08A board at high speed.
Image Signal Acquisition Block Diagram
Image acquisition timing is shown below.
PMT board
Quasi-reading
Input buffer
Shading correction
Filtering
A/D conversion
Output buffer
IMG board
Laser
Scan over IP
PMT output signal in main-scan direction
Light-collecting guide
Output level
Accelerated phosphorescence light is guided to PMT
by the light-collecting guide
FR1H0240.EPS
OFCLKL
OLCLKL
OLCLKL
Enlarged view
OPCLK
Image data [10 : 0]
D1 D2 D3 D4
FR1H0241.EPS
009-051-04
05.31.99 FM2460 (1)