Wave front sensor-less adaptive optics based on sharpness metrics for particle image velocimetry

  title={Wave front sensor-less adaptive optics based on sharpness metrics for particle image velocimetry},
  author={Martin Teich and Jan Grottke and Hannes Radner and Lars Buttner and J{\"u}rgen W. Czarske},
  journal={arXiv: Applied Physics},
Optical distortions can significantly deteriorate the measurement accuracy in imaging systems. Such distortions can occur at fluctuating phase boundaries as well as multiple-phase flows and result from the accompanied refractive index changes. Due to multiple reflexes arising from a fluid flow setup, the usage of a wave front sensor (WFS) can be hindered. In this work we outline a wave front sensor-less approach which includes iterative aberration correction with a fast deformable mirror (DM… 
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Active optics: A new technology for the control of light

  • J. Hardy
  • Physics
    Proceedings of the IEEE
  • 1978
Active optical systems are those in which real-time control over optical wavefronts is employed to optimize system perference in the presence of random distrurbances. Applications include 1)