Translator Disclaimer
30 August 2005 Wavefront sensing on extended sources: anisoplanatism effects on phase estimation
Author Affiliations +
The atmospheric turbulence severely limits the resolution of ground based observation systems. Adaptive optics provides a real time compensation of these effects. The correction quality relies on a key component, the Wave Front Sensor (WFS), that analyses the perturbation. When observing extended sources the WFS precision is limited by anisoplanatism effects induced by the distribution of the turbulence in the volume ahead of the instrument. Anisoplanatism induces a variation of the turbulent phase and of the collected flux in the field of view. The apparent evolution of the flux variations is often called differential scintillation. We study the impact of this phase and scintillation anisoplanatism on wavefront sensing. Scintillation anisoplanatism and its coupling with phase effects have to be taken into account. An analytical expression of the error induced on the phase estimate is given in the Rytov regime. The formalism is applied to different cases of observation.
© (2005) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Nicolas Vedrenne, Vincent Michau, Clelia Robert, Jean-Marc Conan, and Thierry Fusco "Wavefront sensing on extended sources: anisoplanatism effects on phase estimation", Proc. SPIE 5894, Advanced Wavefront Control: Methods, Devices, and Applications III, 58940S (30 August 2005);

Back to Top