Laser Scanning Unit (Lsu) - Xerox Phaser 3330 Service Manual

Laser Scanning Unit (LSU)

The LSU is the core part of the IOT that converts video data received from the controller into the
electrostatic latent image on the OPC drum, using a modulated laser beam reflected from the rotating
polygon mirror, exposing the main charge on the OPC drum. The OPC drum is rotated at the same rate
as the media feeding speed.
The HSYNC signal is created when the laser beam from the LSU reaches the end of the polygon mirror
face as it rotates, and the signal is sent to the controller, which uses this to synchronize each scan line
the laser makes in the horizontal axis by adjusting the image data sent to the LSU. Each face of the
polygon mirror is used for one scan line on the OPC drum.
Photo Diode
Laser Diode
Driver Circuit
Protector Panel
Xerox Internal Use Only
OPC Drum
Laser Diode
Polygon Mirror
Motor Driver
Phaser 3330 and WorkCentre 3335/3345
General Information
Polygon Motor
s3320-264
1-29
Service Manual