THORLABS BC207UV, Руководство по эксплуатации

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BC207 Series
Chapter 5: The Graphics User Interface (GUI)
Rev: 8.1, 10-Jan-2022
Page 42
© 2022 Thorlabs
Attention
The calculation area must not cut off lower intensity parts of the beam profile. This may
cause inaccurate calculation results!
Note
When the ROI size or position is changed and the Calculation Area was not set to 'Automatic'
and does not fit into the new ROI, the Calculation Area will be reset to 'Full Size', in other
words, to the new ROI.
5.5.4.2 Averaging Mode
Two modes are available - floating and block.
When using an averaging mode, please also define the number of averaged frames, which can
be set from 1 to 100.
In Floating mode , the average is calculated from the weighted previous average and the re-
cent frame. Example: Floating average is made for 10 frames. The previous average value is
multiplied by 9, then the recent frame value is added and the sum is divided by 10, which gives
the new average value.
In Block mode , the indicated number of frames is accumulated, after acquisition the average is
calculated and displayed. This is the slowest mode.
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.
5.5.4.3 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.
5.5.4.4 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.
In comparison to the software trigger function of the Beam Software, Hold Maximum will only
store and analyze maximum values, while in software trigger, a threshold can be set.
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