OKIDATA OL400e Series, Service Manual

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Service Manual for OL400e/OL410e/OL410e-PS
Chapter 2 Principles of Operation
2.4.05 Exposing
The image drum has four layers.
- Carrier Transfer Layer (CTL)
- Carrier Generation Layer (CGL)
- Underlayer (UL)
- Aluminum Base
The CTL and CGL make up the organic photo conductor layer (OPC), which is about 20
micrometers (mm) thick.
When 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. The negative carriers flow into the aluminum layer
(ground).