Laser Exposure; Overview - Ricoh PE-P1 Service Manual

Laser Exposure

Overview

1. LD unit - C/M
2. Fθ Lens
3. Polygon Mirror Motor
This machine uses two LDB 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. The polygon mirror motor rotates the mirrors clockwise and each mirror
reflects beams from LD unit.
The laser beam from the LD unit - C/M is directed to the Fθ lens at rear side by the polygon mirrors. The
laser beam from the LD unit - K/Y is directed to the Fθ lens at front side by the polygon mirrors.
Laser exposure for magenta and cyan starts from the left side of the drum, but for yellow and black it starts
from the right 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.
The machine has one laser synchronizing detector board (LSD) as shown above. The board detects four
colors. The LSD detects the start of the main scan.
4. Synchronizing Detector Board
5. LD unit - K/Y
Laser Exposure
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