MINOLTA-QMS magicolor 6100 Series Service Manual page 90

PRINT Signal
VIDEO Signal
Page 1-34
4.6.2.2 Laser Drive Control Circuit
The laser drive control circuit (LDC) consists of the video signal input
circuit, drive circuit, laser diode, output detection circuit, and output con-
trol circuit (see Fig. 4-34).
4.6.2.2.1
MCTL P.W.B.
Frequency Control
Circuit
Beam Scanning
Control Circuit
Operation of Laser Drive Control Circuit
When a video signal is input, the laser drive circuit switches
the laser diode based on the video signal, and emits a laser
beam.
The output value of the emitted laser beam is detected by the
photo detector (PD), and feeds back to the output control cir-
cuit.
The output control circuit compares and controls the set value
for the laser output as well as the value fed back from the out-
put detection circuit, so that the emitted output of the laser
diode remains constant.
The laser beam scanned by the scanner motor is detected by
the beam detector (PD), and is output as the synchronized
position signal (BDT). This signal is to initiate the printing.
Synchronizie
Control Circuit
LCD P.W.B.
Fig. 4-34
OPC Belt
F - Ø Lens
PD
Laser
BDT
magicolor 6100 Series Service Manual
Scanner Motor