Lsu ( Laser Scanning Unit ) - Samsung CLP-770ND Service Manual

2.4.8 LSU ( Laser scanning unit )

LSU consists of LD(Laser Diode) and polygon motor control. For realizing Color Image, it is controled by
4 LD. When the controller generate the printing signal, LD will turn on and Polygon motor starts.If the
receiving part in LSU detect the beam , Hsync is generated. When the rotation of polygon motor is steady,
it is time of LSU ready status for printing. If either of two condition is not satisfied, LSU error is expected.
Photo Diode
LD Driver circit
Protector panel
Trouble
Polygon Motor Error
Hsync Error
Service Manual
Product spec and feature
LD(Laser Diode)
Failure Analysis
The Rotation of Polygon Motor can not reach stable
Though the rotation of Polygon Motor reach stable, the signal of Hsync is
not occurred
2-27
OPC Drum
Polygon Mirror
Polygon Motor
Motor Driver
Samsung Electronics