e-STUDIO520/600/720/850 SCANNING SECTION March 2005 © TOSHIBA TEC
6 - 6
6.4 Control for Exposure Lamp
6.4.1 General description
Control circuit of the exposure lamp consists of the following 3 blocks.
1) Lighting device for the Xenon lamp (Lamp inverter board)
Turns the exposure lamp ON/OFF.
2) CCD sensor circuit
This circuit works to the convert the reflected light amount from the original surface and the shading
correction plate to the electrical signals. The reflected light amount from the shading correction plate
is read to control the exposure amount.
3) Image processing circuit
The output signals from the CCD are digitized and the image processing such as gamma correction
and shading correction is applied to them.
Fig.6-5
CCD board
CCD sensor
SLG board
Exposure lamp (Xenon lamp)
ASIC
Scanner
CPU
Analog Front End
(AFE)
Lighting device for
xenon lamp
(Lamp inverter board)
Shading correction plateOriginal
To Next Page
Loading...
