ON THE USE OF HARMONIC SIGNALS FOR SIMULATING THE OPERATION OF MEASURING AND CORRECTING OPTICAL SYSTEMS IN A TURBULENT ATMOSPHERE
V. P. Lukin
Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk, Russia
Keywords: turbulence, time evolution, harmonic signal, phase distortion
Abstract
The question of the correctness of using a harmonic signal to simulate the operation of measuring phase systems, for example, adaptive optics systems that measure and correct turbulent distortions, is investigated. The time evolution of phase distortions for an optical wave as it propagates in a turbulent atmosphere is estimated. When analyzing the evolution of phase distortions in an optical wave caused by the action of turbulence, the ratio of the dispersions of the first and second derivatives is calculated for the increment of phase distortions over a certain time interval. The magnitude of this ratio is compared with the same value obtained in modeling temporary distortions when using a harmonic signal. When modeling the time evolution of phase distortions using harmonic signals, it is necessary to take into account not only the first derivative of this increment, but also, at a minimum, the second derivative.
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