THORLABS M2MS, Руководство по эксплуатации

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BP209 Series 6 The Graphics User Interface (GUI)
Rev: 8.1, 14-Feb-2022 © 2022 Thorlabs Page 35
In Rolling mode , the averaging is done over the indicated most recent number of frames.
Example: Rolling average is made for 10 frames. The most recent 10 frames are averaged and
displayed, the value is updated with each new frame.
Setting the frames to numbers higher than 1 enables noise reduction.
This option is helpful for unstable light sources with fluctuating intensity or beam shape, or if the
update rate on the screen is too high for easy data readout. Also use this option to suppress
Beam Profiler noise in case of low intensity.
6.5.4.3 Clip Level
In contrast to the Calculation Area Clip Level , the Clip Level parameter is used to determine
the beam width. It defines a relative intensity level between dark level (0%) and peak level
(100%) of the measured beam profile at which the beam width is determined. The ISO11146
Standard recommends a default value of 1/e² =13.5 % of the peak intensity. Other values from
5% to 95% can be set by entering manually.
Click on Default (1/e²) to set the default Clip Level of 13.5%. See Appendix Application Note
for details.
6.5.4.4 Hold Maximum
The Hold Maximum feature is recommended for pulsed laser sources. In all subsequent scans
for each pixel only the maximum values are stored, displayed and used for calculation.
6.5.4.5 Autoscale to Peak
Enable the " Autoscale to Peak" check box to scale the X and Y profiles to their peak intensit-
ies. Disabling will scale the X and Y profiles to the value of AD saturation.
6.5.4.6 Correct Beam Width
The Correct Beam Width option should be activated by default.
It corrects for the measurement error due to the finite slit width for all methods (13.5% clip level
with and without Gaussian fit). Since this convolution error is systematic it can be calculated
and eliminated. This feature increases the measurement accuracy, particularly when measuring
narrow beams.
6.5.4.7 Reference Position
The reference position influences the calculation results. Peak and Centroid positions refer to
the reference position. By default, the reference position is set to the sensor center. In the 2D
Reconstruction window it is displayed as a grey crosshair.
The Reference Position can be set to predefined positions (see above) or to a user defined po-
sition. The X and Y coordinates of a user defined position are to be entered numerically or set
in the
2D Reconstruction (Reference Position Editor):
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