Ricoh PRIPORT VT 2000 Series Service Manual page 43

28 February '91
2.4.2 The Image Signal :
CCD Board
{
A/D Converter
LSYNC (5,120)
SH
∅10,
Input
∅20,
RS
{
Output OS
SH (CN801-20)
∅
∅10, 1B, ∅1E (CN801-14, 6, 18)
∅
∅20, 2B, ∅2E (CN801-12, 8, 16)
Dummy Pixels:The dummy pixels generated by the area covered with alumi-
num film. The dummy pixels are used as the standard black
level.
The first 32 pixels read (D0 to D31) are dummy pixels. Pixels D32 to
D5,032 are the effective pixels (S1 to S5,000). After that there are four
more dummy pixels. Therefore, the total pixel count from the CCD, including
the dummy pixels, is 5,036.
As the image signal captured by the CCD is clocked out by the shift gate
every 3 ms (scan line period), there remains time for 84 transmission clock
pulses after all the image data from the CCD has been output. These clock
pulses, after all valid data have been clocked out, constitute empty data.
During this period, subscanning occurs.
CN801-2
RS
CN801-4
OS
CN801-6
1B
CN801-8
2B
CN801-12
20
CN801-14
10
CN801-16
2E
CN801-18
1E
CN801-20
SH
CN801-9, 10
+12V
CN801-1, 3, 5, 7, 11, 13, 15, 17, 19
GND
CN602-1, 3, 5, 7, 11, 13, 15, 17, 19
∅
1B, ∅1E
∅
2B, ∅2E
RS (CN801-2)
OS (CN801-4)
CN602-2
CN602-4
CN602-6
CN602-8
CN602-12
CN602-14
CN602-16
CN602-18
CN602-20
CN602-9, 10
3 ms (5,120 Count)
Photo Signal Storage Time (3 ms)
Dummy
Effective
Pixels 32 Pixels
5,000
2-16
A/D Converter
5,120
4,096
Empty Data 84
Dummy Pixels 4