THORLABS WFS20-14AR, Руководство по эксплуатации

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5 Operating Instruction
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Wavefront Data
These wavefront statistics are displayed in microns or waves, depending on the user selection
(
Wavefront Sensor Setup Panel ). Calculated data are related either to the entire wavefront
image or to the pupil interior only. The pupil area defines the area of interest of the beam and
can be defined by the user. Please see the section Pupil Definition Tab for information on en-
tering the pupil parameters.
The calculated wavefront statistics refer to the wavefront display (Measured, Reconstructed or
Difference), selected in the
Wavefront Panel :
PV Total Peak-to-Valley value, i.e., the maximum variance of the wavefront in the ob-
served area
RMS Root Mean Squared average value
wRMS Intensity weighted Root Mean Square average value
Higher intensity spots in the pupil center have more weight than lower intensity
spots away from the center.
Fourier Constants
The Fourier Constants M, J0 and J45 are derived from the Zernike coefficients. Depending on
the setting in the
Zernike Fit Tab of the Wavefront Sensor Setup Panel , Zernike orders up
to 2, 4 or 6 are used to calculate these constants.
Optometric Constants
Optometric Constants are Sphere, Cylinder (in diopters) and the Axis Angle of the cylinder in
degrees. Depending on settings in the
Zernike Fit Setup panel, Zernike orders up to 2, 4 or 6
are used to calculate these constants.
Radius of Curvature RoC
This parameter is based on the 5th Zernike term 'Defocus' and describes the degree of
curvature of the measured wavefront. All other Zernike terms and corresponding wavefront de-
formations are left unnoticed and only the spherical term is considered. The Radius of
Curvature (RoC) is equal to the distance (in air) between the reference plane of the WFS and
the point source of the spherical wavefront.
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