Toshiba manual STUDIO3511/4511 Laser Optical Unit November 2003 Toshiba TEC

8

(2) Polygonal motor unit

This unit consists of the polygonal motor, polygonal mirror and polygonal mirror cover.

a.Polygonal motor

This motor rotates the polygonal mirror in high speed.

The DC motor controls the rotation speed of

the mirror motor as follows: During ready : 10,000.00 rpm During printing : 36,734.37 rpm (600dpi)

:37,322.12 rpm

(FAX 15.4x16.0dot/mm)

:35,922.54 rpm

(FAX 16.0x15.4dot/mm)

b.Polygonal mirror

One laser beam emitted from the laser diode is reflected by this mirror. As the polygonal mirror is rotated by the polygonal motor, the reflected laser light moves in sync with the rotation. The direction of the movement is the primary scanning direction of the image. One scan is performed on one plane of the polygonal mirror.

As the polygonal mirror has eight planes, eight scans are performed in one rotation of the polygonal mirror.

c.Polygonal mirror cover

Polygonal mirror cover reduces the windage loss and noise, prevents adhesion of foreign matters onto the mirror surface and releases heat.

(A)

Drum

Laser light

(B)

Drum

Laser light

(C)

Drum

Laser light

Fig. 8-202

One scan is completed by completion of steps (A) to (C). One scan is performed on one plane of the polygonal- mirror. Eight scans can be made with one rotation of the polygonal mirror.

e-STUDIO3511/4511 LASER OPTICAL UNIT 8 - 4 November 2003 © TOSHIBA TEC