110 Theory of operation EN
Photosensitive drum
The special properties of the photosensitive drum allow an image to be formed on the drum surface
and then transferred to paper. The drum is an aluminum cylinder coated with a layer of organic-
photoconductive material (OPC) which is non-toxic. The OPC material has properties similar to a
photoresistor. It becomes electrically conductive when exposed to light. (The negative charges
deposited on the drum are conducted to the ground potential of the drum base.) Areas not exposed
to light remain nonconductive and maintain their negative charge. The aluminum base of the
photosensitive drum is electrically connected to ground potential.
Figure 20. Photosensitive drum
Cleaning the drum
The cleaning blade is in contact with the surface of the drum at all times. As the drum rotates during
printing, excess toner is scraped off and stored in the waste toner receptacle.
Figure 21. Cleaning the drum
Photosensitive
Layer
Aluminum
Base
Commentaires sur ces manuels