Toshiba e-STUDIO 206, Service Manual

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© February 2007 TOSHIBA TEC CORPORATION All rights reserved e-STUDIO166/206
COPY PROCESS
3 - 3
2) Charging
Charging is the process to apply charge evenly on the drum surface.
The needle electrode produces negative corona discharge is controlled by the grid, allowing the
drum surface to be evenly charged with the negative potential.
The surface potential on the drum is determined by the grid potential and is controlled to a certain
value by the grid control circuit.
Fig. 3-4
3) Data reading (scanning)
Data reading is the process of illuminating the original with light and converting the reflected light
into electrical signals.
This equipment uses the CIS (Contact Image Sensor) for data reading.
The optical image information read by the CIS is converted into electrical signals (image signals),
which are then transmitted to the image processing section.
Fig. 3-5
Fig. 3-6
Main charger
Drum rotation
Grid control circuit High-voltage
transformer
CIS
Image processing
section
(Example)
Light
receiving
amount Value of image
signals to be
output
255
0
Difference between
"light " and "dark" is
divided into 256 steps.
Light
Dark