THORLABS WFS20-14AR, Operation Manual

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Wavefront Sensor
Noise Cut Level
The Noise Cut Level defines a brightness level (in digits), which a spot in-
tensity must exceed to be included in the data analysis. This level can be set
to exclude contributions of ambient light and noise terms. This parameter is
set in the Lineview panel. Since defining such a fixed level is problematic when beam intens-
ities and ambient light are changing, the Auto setting is highly recommended, as it enables dy-
namic adaption to the different intensity levels for each spot area and yields the best results for
centroid calculation.
The noise cut level values can also be set manually between 0 and 255 digits.
Attention
Improper manual settings for 'Noise Cut Level' may lead to increased measurement er-
rors.
Black Level
Black Level is a camera setting that adjusts the brightness level offset for all illu-
minated pixels. It should be adjusted so that the entire minimum line in the
Lineview panel is below zero and the entire maximum line is above zero. In
the case of very high noise level, reduce the setting. "Arbitrary Unit" (a.u.) values
range from 0 to 255.
Examples:
Black Level set to 255 - this is too high: the lowest intensity pixels (lower
gray curve) show high offset.
Black Level set to 0 is acceptable, as the entire minimum line is below zero,
and the entire maximum intensity line is above zero. The maximum intensity
line includes the low-intensity pixels between the spots, which preserves the
measurement sensitivity.
An automatic adjustment is currently not supported by any of the Thorlabs WFS cameras.
Therefore, it is suggested to check the correct setting.
Set Default
Click on 'Set Default' to restore the factory default values:
·
Noise Cut Level = Auto
·
Exposure Time and Master Gain = Auto
·
Black Level = 0
·
Disable Hardware Trigger
Settings for Camera Image Size and Averaging remain unchanged.
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