Laser Exposure - Gestetner B147 Service Manual

LASER EXPOSURE

6.6 LASER EXPOSURE
6.6.1 OVERVIEW
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1. Synchronizing detector board-Y, K-E
2. LD unit-Y
3. LD unit-K
4. LD Mirror-M
5. LD unit-M
6. LD unit-C
7. F-theta lens-M, C
8. Synchronizing detector board-M, C-S
9. Synchronizing detector board-M, C-E
This machine uses four LD units and one polygon mirror motor to produce latent
images on four OPC drums (one drum for each color toner).
There are two hexagonal mirrors. Each mirror reflects beams from two LD units.
The LD unit for black has two laser diodes to do dual beam writing (this is only
done for black-and-white printing; for full color printing, only one of the beams is
used).
Laser exposure for magenta and cyan starts from the rear side of the drum, but for
yellow and black it starts from the front side of the drum. This is because the units
for magenta and cyan are on the other side of the polygon mirror from the units for
yellow and black.
B147/B149/B190
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10. OPC drum-M
11. WTL
12. OPC drum-C
13. OPC drum-Y
14. OPC drum-K
15. Synchronizing detector board-Y, K-S
16. F-theta lens-Y, K
17. Polygon mirror motor
18. LD Mirror-K
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B146D521.WMF
SM