Laser Exposure - Ricoh G147 Service Manual

6.4 LASER EXPOSURE

6.4.1 LASER EXPOSURE OVERVIEW
1 LD unit
2 Cylindrical lens
3 Polygonal mirror
4 Shield glass
5 Mirror
This machine uses two laser diodes to produce electrostatic images on an OPC drum. The
laser diode unit converts image data from the BICU board into laser pulses, and the optical
components direct these pulses to the drum. To produce a high quality copy image, these
are 256 gradations for the laser power.
The output path from the laser diode to the drum is shown above. The LD unit outputs two
laser beams to the polygon mirror through the cylindrical lens and the shield glass.
Each surface of the polygon mirror reflects two full main scan lines. The laser beams go to
G147
6 Synchronization detector
7 BTL (Barrel Toroidal Lens)
8 F-theta mirror
9 Toner shield glass
6-12 SM