Write Control - Olivetti d-Color 201MF Theory Of Operation

Theory of Operation Ver. 1.0 Sep. 2008
8.2.2

Write control

(1) Laser exposure process
1. Laser beam irradiated by the laser diode is reflected on the polygon mirror.
2. The polygon mirror is a four-faced mirror that rotates at high speed motored by the
polygon motor. The polygon mirror reflects the incoming laser beam in the main
scanning direction and reflects it on the G1 lens.
3. The G1 lens corrects the converging angle of the incoming laser beam and reflects
it on the return mirror 1.
4. Return mirror 1 reflects the laser beam collected by the G1 lens to the G2 lens.
5. G2 lens reflects the laser beam collected by the return mirror 1 on the return mirror
2.
6. The return mirror 2 irradiates the laser beam came from G2 lens to the PC drum.
Return mirror 2
SOS sensor
(2) Laser emission timing
• When a ready signal is detected after the lapse of a given period of time after a print
cycle has been started, a laser ON signal is output from the printer control board.
• The laser ON signal triggers the firing of each laser light which illuminates the SOS sen-
sor via the polygon mirror, G1 lens, and SOS mirror to generate a SOS (Start of Scan)
signal.
• This SOS signal unifies the timing at which laser light is irradiated to each main scan line.
Y109670-2
Polygon motor
Laser diode
Theory of Operation
8. Write section (PH section)
PC drum
SOS mirror
Return mirror 1
G2 lens
4038T2C028AA
G1 lens
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