THORLABS WFS20-14AR, Руководство по эксплуатации

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5 Operating Instruction
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It is recommended that the Circular Pupil be used with the appropriate diameter and center po-
sition. In this case, only the X diameter needs to be entered and the Y diameter is set to the
same value.
Pupil Center (mm)
The pupil center coordinates (in mm) can be set manually or
automatically.
Enabling
Use Beam Centroid is recommended in order to
automatically adapt the pupil center to the measured beam
centroid coordinates. In case of fluctuations of the beam position during the measurement, the
Wavefront Sensor will automatically follow the moving spot. If switching to manual input, use
the button to set the pupil centroid to the center of the Wavefront Sensor.
Note
Manual definition of the pupil center requires a careful and stable beam adjustment, otherwise
the measurement accuracy drops.
It is recommended that the pupil size and position be reviewed and updated using the appropri-
ate functions in the
Spot Field and Beam View displays. The Show Pupil option must be en-
abled in the appropriate configuration panels.
Note
The option Use Beam Centroid must be switched off when entering the High-Speed Mode of
WFS20 instruments, because the beam centroid cannot be measured with a sufficient accuracy
in High Speed Mode.
Limit Wavefront Calculation and Display to Pupil Interior
By default, the wavefront parameters are calculated over the
entire selected sensor area, while the Zernike functions are cal-
culated only for the area of the pupil interior. Enabling this option will limit the wavefront calcula-
tion and display to the pupil interior as well - the 3D wavefront display on the
Wavefront
Panel will show only the wavefront data within the pupil.
Note
Selecting this option influences the total measured wavefront distortions (PV, RMS). Distortions
within the defined pupil area are usually lower that the total measured distortions outside the
pupil.
Set Default
Click on 'Set Default' to activate the factory default values:
·
Circular pupil
·
Use Beam Width = disabled
·
Manual Pupil Diameter = 3 mm
·
Use Beam Centroid = enabled
·
Limit to Pupil Interior = disabled
Area of Interest (AOI)
The AOI functionality allows the measurement area to be limited to a rectangular region called
the Area of Interest (AOI). Similar to the option “Limit wavefront calculation and display to pupil
interior” that limits the wavefront display and the appropriate numerical parameters to the pupil
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