THORLABS WFS150, Operation Manual

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74 WFS150 / WFS150C Manual
© <2007> ... Thorlabs GmbH
Switch to 'waves' unit and then input the operating wavelength of your light
source. The accepted wavelength range is 200 to 1100 nm and corresponds to
the wavelength range of model WFS150C.
Cancel Average Wavefront Tilt
In practice, the direction of the input beam is not perfectly perpendicular aligned
to the sensor area. The measured wavefront is thereby mainly determined by tip
and tilt and the interesting but small wavefront deformations are not seen in the
wavefront panel. Since wavefront tip and tilt is often less interesting, this option
allows you to cancel the average tip and tilt contribution to be canceled prior to
wavefront and Zernike calculation.
Note: The average wavefront tip and tilt will not be removed completely. Small
relicts are still visible in terms of Zernike coefficients Z
1
and Z
2
. Also note that
Zernike terms Z
1
and Z
2
are not related to the original wavefront but the tilt-
corrected wavefront when the 'Cancel Average Wavefront Tilt' option is enabled.
Default Settings
At first program start, the following default settings become active:
·
Wavefront Reference = Internal Reference
·
Wavefront Unit = µm
·
operating wavelength = 633 nm (red HeNe)
·
Cancel Average Wavefront Tilt = off
4.3.3.4 Zernike Fit Setup
This setup panel contains definitions of the Zernike Fit that directly influence the
wavefront representation in terms of Zernike coefficients and wavefront
reconstruction.
To open the setup panel you can use the Menu
à
Setup
à
Wavefront Sensor
entry or simply click right on one of the graphs on the right hand side of the main
panel. Select the tab ' Zernike Fit '.