ABSTRACT
Most atmospheric-turbulence-compensation experiments have been performed under weak-scintillation conditions; conventional phase-conjugate adaptive-optics systems usually provide good correction for these conditions. We have performed an experiment over a 5.5-km horizontal propagation path to explore the efficacy of conventional adaptive optics in strong-scintillation conditions. The experimental results showed a significant degradation in correction as the scintillation increased. The presence of branch points in the phase appears to be the primary reason for the degradation in correction as the scintillation increases.
ABSTRACT
We present experimental results that demonstrate real-time, atmospheric-turbulence compensation of a bright star with the use of two synthetic beacons. Each beacon was used to measure the phase aberrations over only part of the telescope aperture, a configuration that is suitable for reducing focal-anisoplanatism error. To our knowledge, this is the first demonstration of atmospheric compensation with the use of multiple synthetic beacons.
ABSTRACT
We report the use of an integrated-optics wave-front measurement sensor to measure with 200-nsec temporal resolution the phase and intensity at the aperture of a high-power (3.5-MW peak power) flash-lamp-pumped pulsed dye laser. The measurements reveal large fluctuations of the dye-laser wave front during the 2-microsec duration of the laser pulse. The fluctuations and the resulting poor beam quality are attributed to inhomogeneous heating of the dye during the pulse. These high-temporal-resolution measurements, which are not possible with other state-of-the-art wave-front analyzers, explain the previously measured poor beam quality of the laser.
