Oki OKIFAX 5950 Series Maintenance Manual page 458

R76-
The image drum surface is charged to about -750 V by the contact charge of the charge
roller.
When the light from the LED head irradiates the image drum surface, the light energy
generates positive and negative carriers in the CGL. The positive carriers are moved to
the CTL by an electrical field acting on the image drum. Likewise, the negative carriers
flow into the aluminum layer (ground).
The positive carriers moved to the CTL combine with the negative charges on the image
drum surface accumulated by the contact charge of the charge roller, lowering the
potential on the image drum surface. The resultant drop in the potential of the irradiated
portion of the image drum surface forms an electrostatic latent image on it. The irradiated
portion of the image drum surface is kept to about -100 V.
OF5750/5950 Series January 2001
(V)
—750
Image drum
surface potential
—100
0
Charged part
Light
from
LED
Part Charged
irradiated part
by
LED
A3 - 30