Ricoh PRIPORT VT 2000 Series Service Manual page 40

2.3 LENS
312.5∅
Original
Surface
This consists of 6 lenses, to transfer the image, correctly oriented, to the
photoelectric elements of the CCD. It is possible to adjust the focus by
moving the lens assembly [A].
<Lens>
Focal distance:
F No.:
The above illustration shows the layout to transfer the image from an A3
original (297 millimeter width) to the CCD [B].
<CCD>
Number of effective pixels:
Reading length:
Photo signal storage time:
The shading plate [C] corrects light intensity distortion. The light intensity is
low at the both ends of the lamp and is also low at the edge of the lens.
Therefore, the center light is cut to make the light intensity uniform.
5 mm
404.179 mm
Exposure Glass
43 mm (43.05
F4.5
30.655 mm 29.895 mm
[A]
0.32 mm)
±
5000 pixels
312.5 mm
3 msec.
2-13
28 February '91
35∅ mm
[B]
[C]