Printing; General Description - Toshiba DP1600 Service Manual

8. PRINTING

8.1 General Description

The laser scanner unit reflects the laser beam by the polygonal mirror motor and irradiates it in the
scanning direction of the drum through the fθ correction lens. As the drum rotates, an electronic image is
formed on the drum.
The laser scanner unit consists of the following:
• Laser unit which outputs a laser beam.
• Polygonal mirror which moves the laser beam in the scanning direction of the drum.
• fθ correction lens which makes uniform the rate at which the laser beam reflected by the polygon
mirror reaches the drum.
• Polygonal mirror motor drive PWA which controls the polygonal mirror motor.
• Laser drive PWA which controls the laser beam.
• Hsync detection mirror, lens and Hsync detector which detect the Hsync signal on which the first
printing position for every scanning is based.
The laser scanner unit is precisely adjusted and assembled in a clean room to avoid the entry of dust
which can cause trouble. For that reason, the laser scanner unit cannot be disassembled or adjusted in
the field.
Polygonal mirror
Polygonal mirror
motor drive PWA
December 2000 © TOSHIBA TEC
Laser drive PWA
Lens
Fθ correction lens 1
Fig. 8-1-1
Aperture
Hsync detector
Fθ correction lens 2
8 - 1
Lens
Laser diode
Lens
Hsync detection
mirror
08-01-01
1600/2000/2500 PRINTING