B-70315EN/02 8.LASER OPTICAL SYSTEM
- 251 -
8.5 POWER CALIBRATION METHOD
8.5.1 Setting a Power Input Compensation Coefficient
After replacing the rear mirror of the laser oscillator or replacing the
power sensor unit, check and set the power input compensation
coefficient. A laser beam is directly measured. So, be sure to strictly
observe the safety precautions related to a laser beam.
(1) Set the following parameters:
PRM No.15208 4096 (For C4000-E, C5000-E, C6000-E)
6144 (For C1000-E, C2000-E)
PRM No.15209 100 (For C1000-E), 200 (For C2000-E)
400 (For C4000-E), 500 (For C5000-E)
600 (For C6000-E)
(2) By collecting the mode, check if the mirrors of the oscillator are
aligned correctly. If the mode is incorrect, make a readjustment.
(3) Perform internal discharge at the rated output for 1 minute or
more, run the program below in the automatic mode, and place a
power probe in the middle of the optical path to measure the
output value Pr of a laser beam irradiated outside.
At this time, it is recommended to make a measurement at the
beam outlet.
Record the actual output value Pa displayed on the laser setting
screen simultaneously with this measurement.
G32 P1 Q1 ;
G24 S1800 Q100 R20000 ;
G32 P0 ; (irradiation for 20 seconds)
M30
Use a power probe calibrated periodically. Calibration coefficient
data is attached to a calibrated power probe.
The correct measurement value is: Pr' (probe-converted value) =
Pr (probe reading) × calibration coefficient.
(4) If power input compensation coefficient K is set correctly in
PRM No. 15215, Pa = Pr' should result. If the value of Pa differs
from Pr' by ±5% or more, set power input compensation
coefficient K (PRM No. 15215) again according to the following
expression:
K (new value) = Pr' (probe-converted value)/Pa × K (old value)
(5) Make a measurement again as described in step (3) above to
check that Pa = Pr'.