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Brother HL-1060 User Manual

Page 37

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CHAPTER II -21

2.5.2

Exposure Stage

After the drum is positively charged, it is exposed to the light emitted from the laser unit.

Fig. 2.26

The area exposed to the laser beam is the image to be printed. The surface potential of the
exposed area is

reduced forming the electrostatic image to be printed.

1 Cycle of drum

Surface Potential (V)

+1000

+700

+400
+300

1

2

3

4

(a)

(b)

Time

1

2

3

4

Primary charging

Laser beam exposure and developing
(a) Unexposed area
( Non image area )
(b) Exposed area
( Image area )

Transfer the image to paper

Erase the residual potential

Drum
Sleeve

Fig. 2.27

Drum

Paper

Laser beam

f lens

Polygon mirror

Motor

Lens

Laser diode

Laser detector

Laser Beam