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Image formation system – Brother HL-1260 User Manual

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3.

IMAGE FORMATION SYSTEM

3.1 Outline

The image formation system is the main part of the printer. The print information, after input from
the video controller circuit into the engine controller circuit as a TVDO signal, forms a toner image
on the photosensitive drum.

Then the toner image is transferred onto the paper by the transfer charging roller. The image
formation system is composed of the photosensitive drum the charging unit, the developing unit
and the cleaning unit.

3.2 Printing Process

The major part of the image formation system is contained in the cartridge, as shown in Figure
2.5.

The cartridge used by the printer has a seamless photosensitive drum with the structure shown
in Figure 2.6. The outer layer of the drum consists of an organic photoconductor (OPC); the base
is aluminum.

The printing process can be divided into five major stages:

Figure 2.5

Base

Photoconductive layer

Laser beam

Developing cylinder

Primary charging roller

Cleaning blade

Photosensitive drum

Static charge eliminator

Cartridge

Transfer charging roller

Blade

Figure 2.6

1. Electrostatic latent image formation stage

Step 1 Primary charge (-)

Step 2 Scanning exposure

2. Developing stage

Step 3 Development

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