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e-STUDIO555/655/755/855
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LASER OPTICAL UNIT
7 - 6
7.2.2
Polygonal motor unit
This unit consists of the polygonal motor (M2), polygonal mirror and polygonal mirror cover.
a. Polygonal motor
This motor rotates the polygonal mirror at a high speed. The DC motor controls the rotation speed of
the motor.
b. Polygonal mirror
The e-STUDIO555/655 has a 1-beam type of laser unit. One laser beam emitted from the laser
diode is reflected by this mirror. As the polygonal mirror is rotated by the polygonal motor (M2), the
reflected laser beam moves in sync with the rotation. The direction of the movement is the primary
scanning direction of the image. One scan is performed on 1 plane of the polygonal mirror. As the
polygonal mirror has 8 planes, 8 scans are performed in 1 rotation.
e-STUDIO755/855 has a 2-beam type of laser unit. Two laser beams emitted from the laser diode
are reflected by this mirror. Two scans are performed on 1 plane of the polygonal mirror. As the
polygonal mirror has 8 planes, 16 scans are performed in 1 rotation.
Fig. 7-6
(A)
Drum
Laser beam
(B)
Drum
Laser beam
(C)
Drum
Laser beam
(A)
Drum
Laser beam
(B)
Drum
Laser beam
(C)
Drum
Laser beam