From deformable mirror pointing at sky to underwater acoustics

• Autorzy: Niebergal J. , Zielinski A. , Caputa K.
• Języki publikacji: EN

Abstrakty

EN

Due to air density variations, turbulence, eddies, and cross winds in the atmosphere, ground-based telescopes record temporal and spatial fluctuations of phase and amplitude of received stellar light. For astronomical imaging, the effects of the atmosphere result in aberrations of received light leading to blurring and other undesired affects. Using a complex optical system called adaptive optics, aberrations can be effectively reversed resulting in improved imaging quality. Similarities between the atmosphere and ocean are apparent when considered as a propagation medium for light or sound, respectively; both media are turbulent and governed by similar dynamic processes involving temperature gradients, pressure differentials, and other factors. Similarities also exist in the distortions that the changing medium produces on each wavefront. In presenting the adaptive optics solution that has improved ground-based astronomical imaging, this paper will propose that similar strategies could be utilized in underwater acoustics.

• Wydawca: Polskie Towarzystwo Akustyczne. Oddział Gdański
• Czasopismo: Hydroacoustics
• Rocznik: 2011
• Tom: Vol. 14
• Strony: 171--180
• Opis fizyczny: Bibliogr. 19 poz., rys.

Twórcy

autor

Niebergal J.

autor

Zielinski A.

autor

Caputa K.

• University of Victoria, Dept. of Electrical and Computer Engineering P.O. Box 3055 STN CSC Victoria, B.C., Canada, V8W 3P6,

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