Abstract

The structure function of atmospheric phase fluctuations is defined as follows: A generalised model for the structure function of phase is: ℛ₀ is related to the size of the long-exposure image formed by a large-aperture telescope, while γ_ß is a parameter which depends on ß and on the precise definition of ℛ₀ The widely-used Kolmogorov model of refractive index fluctuations [1] predicts a value of 11/3 for ß; in this case, with the appropriate definition, ℛ₀ is equivalent to r₀, the Fried parameter [2], Under the Kolmogorov assumption, the parameter r₀ entirely describes the time-averaged statistics of the phase fluctuations. A knowledge of r₀ can be used, for example, to predict how the energy in the phase fluctuations is distributed between the Zernike modes.

© 1996 Optical Society of America