Fundamentals Of The Electro-Photographic Process - Oki B 4100 Maintenance Manual

3.1

Fundamentals of the Electro-Photographic Process

The electro-photographic process involves six sub-processes:
(1) Charging (2) Exposure (3) Development (4) Transfer (5) Fusing (6) Cleaning
Outline of each process is explained below.
Process
1
Power
Supply
2
Power
Supply
3
40055101TH Rev.4
Illustration
Charge roller
EP drum
LED head
Charge roller
EP drum
Developing roller
EP drum
Description
The surface of the electro-photographic
Image drum is uniformly charged with
negative charges by applying a negative
voltage to the charge roller.
When the applied DC voltage exceeds a
threshold value, charging of the drum
begins.
Light emitted from the LED head irradiates
the negatively charged surface.
The potential of the irradiated part of the
Image drum surface is raised, so that an
electrostatic latent image associated with
the print image is formed.
Toner is attracted to the exposed part
(high-potential part) of the Image drum at
the contact between the Image drum and
the developing roller, making the electro-
static latent image visible.
At the same time, the residual toner on the
Image drum is attracted to the developing
roller by static electricity.
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