Unitek Miyachi LW250 Operation, Maintenance And Service Manual page 134

ADDENDUM 995-605, REV B
Page 8-4, paragraph titled, Preparation - Following this paragraph, add a new paragraph
as follows:
Burn Pattern Adjustment. To adjust the burn pattern:
1. Set the unit to the Service Mode No. 1 or set the laser output to 300 volts and 0.8 to 1.0
milliseconds.
2. Turn on the high voltage (HV).
3. Open the main (resonator) shutter (MAIN
SHUTTER).
4. Place a sheet of black paper on the optical
axis of the Nd: YAG laser beam, a short
distance from, and on the output side of, the
M4 mirror.
5. Push the laser start switch. The black paper
will be slightly burned and a burn pattern
will be obtained.
6. Rotate the N1 and N2 adjustment nuts of the
M3 mirror so that the burn pattern becomes
circular. (A circular burn pattern has an
interference fringe.)
Unitek Miyachi Lasers Q P. O. Box 5033 Q Monrovia Q CA 91017-7133 Q (626) 303-5676
CAUTION: The circular burn pattern will cause the paper to burn
more intensely, thereby producing more smoke and flame. Lower
the voltage or shorten the pulse width so that the optical parts will
not be stained.
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LW250 OMS MANUAL