Principle Of The Sensor - Toshiba e-STUDIO2500c Service Manual

14.3 Principle of the Sensor

Image quality sensor (S18) projects light onto the transfer belt and the toner image (test pattern) devel-
oped on the transfer belt to output a voltage corresponding to the reflected light amount.
The output voltage is then converted analog-to-digital into reflected light amount signal. The CPU cal-
culates the toner adhesion amount to control the image forming conditions.
Test pattern
(toner image)
Light emitting
element
Light source amount voltage
May 2006 © TOSHIBA TEC
Transfer belt
Light receiving
element
Reflected light
amount voltage
Fig. 14-2
14 - 3
Reflected light
amount signal
A/D
D/A
Light source
amount signal
e-STUDIO2500c/3500c/3510c IMAGE QUALITY CONTROL
CPU
14