THORLABS M2MS, Operating Manual

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BP209 Series 6 The Graphics User Interface (GUI)
Page 28
21424-D02
6.5.1.2 Power Correction
The Power Correction allows the user to set the total beam power measured by the Beam Pro-
filer to the power level measured by a reference power meter.
Preconditions:
Be sure to have set the operating wavelength accurately.
Click the 'Start' button - the Power Correction Dialog appears.
The 'Current power value' is the actual power measured by the Beam Profiler. Enter the power
meter reading into the 'Power meter value' control. Click 'Apply' to enable corrections, then click
'Close' to leave the panel.
The difference between the entered power value and the actually measured by the instrument
power will be displayed as an offset, here -0.161994 dB.
This offset (in dB) is stored in the Beam Profiler and is read out and activated automatically
each time after connecting this instrument.
Note
The user calibrated power reading is correct only at the actual wavelength. If the wavelength
changes, the power correction needs to be carried out again.
After executing the Power Correction it is activated automatically, which is indicated by the
check mark.
The activation state is saved in the software. When restarting the software using the same in-
strument, the offset is recognized, read out and the same activation state (active / inactive) as
in the previous software session will be restored.
If the power correction is not active, the attempt to activate it lets the software check the Beam
Profiler for a saved offset. If no saved offset is found, the Power Correction dialog opens and
asks for a power meter value. If an offset is recognized, it will be applied immediately. For this
reason it is recommended that a power correction is to be performed if the environment of the
instrument was changed.