THORLABS WFS150, Руководство по эксплуатации

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37 Operating Instruction
© <2007> ... Thorlabs GmbH
Optical Power
Due to the implemented automatic shutter control of the CCD camera the
Wavefront Sensor can handle optical power in a wide dynamic range. Note that
the sensitivity is strongly wavelength dependent, see
Typical Wavelength Curves .
Especially at the edges of the sensitive wavelength range (200 - 1100 nm for
WFS150C) there is a drastically reduced sensitivity which allows measurement of
higher power sources directly. On the other hand, the Wavefront Sensor can get
saturated for small beams at the lower mW levels. Use an external attenuator in
that case.
During operation keep in view the on the error window at the bottom. Care about
the 'Power too low', 'Power too high' and also 'High Ambient light level' error and
find a way to correct the power level accordingly. See
Measurement Warnings and Errors chapter for details.
Example Measurements
The following picture illustrates a very simple example measurement that should
establish understanding of what a wavefront is and how it can be influenced.
a) A collimation lens (e.g. bi-convex) positioned at the distance f (its focal length)
from a monomode fiber end face will generate an exactly parallel beam with a
plane wavefront.