Functions - Toshiba e-studio 167 Service Manual

6.3

Functions

1) Original glass
This is a glass for placing original. Original (image) placed on the original glass is scanned by the
CIS. The ADF original glass is used when original is read with the Automatic Document Feeder.
Original is transported on the ADF original glass by the Automatic Document Feeder, and the trans-
ported original is read under the ADF original glass by the CIS. Do not use such solvents as alcohol
when cleaning the surface of the ADF original glass, because it is coated so as not to be scratched
by originals.
2) CIS unit (CIS)
The CIS unit (CIS) is a sensor unit which consists of an LED array, lens array and CCD sensor array
of the same length as that of the original width in the primary scanning direction closely attached
and unified. The original is irradiated at one time with the LED light source which consists of LEDs of
RGB colors (one for each color), light guiding tube to lead each light to the original and a YG-LED
array, and then the reflected light is scanned by the CCD sensor.
In the CCD method (reduction optical method), the reflected light of the exposure lamp is LED
through mirrors, lens and slit to the CCD where the optical-to-electrical conversion for scanned data
is performed. In contrast, in the CIS method (close-contact sensor method), those operations are
processed only by the CIS unit. The CIS has characteristics of shallow depth of focus and high light-
sensitivity.
ADF original glass
- CCD
Scans the light reflected from an original and converts it to an electrical signal.
In order to realize the same-to-scale optical system of A3 width and 7084 image pixels, the
equipment uses 11 CCDs (each CCD has 644 image pixels per line) to make up a CIS sensor of
600x600 dpi resolution for scanning.
- YG-LED array
Works as an assistant light for the RGB light guiding tube. This YG-LED array is used to reduce
the shadow of the original when scanning is performed.This LED array produces the output
power of 7.68W.
© 2007 - 2008 TOSHIBA TEC CORPORATION All rights reserved
Micro-lens array
CIS unit
YG-LED array CCD
Fig. 6-2
6 - 3
Shading correction plate
Original glass
RGB light guiding tube
e-STUDIO167/207/237
SCANNER
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