Toshiba e-STUDIO 550, Service Manual

Page: 47 / 346

JUNE 2002 © TOSHIBA TEC 3 - 3 e-STUDIO550/650/810 COPY PROCESS
CCD light
receiving
amount Value of
image signals
to be output
Light
255
Dark 0
Difference between
"light " and "dark" is
divided into 256
steps.
(3) Scanning
Scanning is a process of exposing the original to
the light and converting the reflection into electrical
signals.
The light reflected from the original is imported to
the charge coupled device (CCD) and this optical
image information is converted into electrical sig-
nals (image signals), which are then sent to the
image processing section.
(4) Writing
Writing is a process of converting the image signals
sent from the image processing section into optical
signals and exposing the drum surface to the light.
Semiconductor laser element converts image sig-
nals sent from the image processing section into
optical signals (laser emission) and exposes the
drum surface to the light to form an electrostatic
latent image on it.
CCD
Image processing
section
(Example)
쩪
쩪
Image
processing
section
Laser Drive
board
Semiconductor
laser element
Polygonal mirror
Photo-
conductive
drum