The facilities of the method of analysis of the vector beam intensity profile at the atmospheric path output are presented. This method is based on the second rank tensors for the discrete differences of the first and second orders intensity distributions. The synthesized distributions of the field values allow to describe the topology of the phase modulation, the contours of intensity variations alterations, to define the area of localization of the beam energy and to estimate the state of polarization. The discrete differential analysis of the time series structure for the intensity distributions is of information value for the meteorological control of wind and termic conditions of the path, sensing of the refraction inhomogeneities types as well as for the analysis of the media spatio-temporal optical activity.
The results of the experimental and theoretical analysis of spatial statistical characteristics of laser beams with wavefront control are presented. The experimental data obtained in different meteorological conditions is used to estimate features of spatial localization of averaged over the ensemble recorded intensity distributions and profiles of second, third and fourth spatial moments. Registered dependence between transverse or longitudinal components of scintillation index and meteorological conditions or setting of beam forming optical system is discussed. In addition, we proposed interpretation of spatial properties of high-order central moments.
A theoretical study is made of geometry average statistical speckles of the intensity of a broadband dispersed laser beam
which is spatially coherent in the initial plane z = 0. Two-dimensional distributions of random intensity are numerically
simulated, which make it possible to trace transformation of speckle patterns in the course of the beam propagation. The
correlation functions and power spectra of random intensity are calculated to show how the characteristic dimensions and
the shape of speckles vary depending on longitudinal coordinate z, the width and shape of the frequency spectrum and
also the degree of dispersion of the light beam. Analytical expressions are derived which show that the speckle
dimensions increase in the longitudinal direction as well as in the direction of the dispersion as the distance from the
initial plane increases. Limit value (at z → ∞ ) of the speckle width in the direction of the beam dispersion is calculated.
The statistical characteristics of spatial fluctuations of the intensity of dispersed laser beams are studied
theoretically. The density of the probability distribution for the intensity is found and its transformation with a change in
the longitudinal coordinate is studied. It is shown that a decrease in the intensity fluctuations and a drop in the contrast of
the beam speckle structure occur with increasing distance from the initial plane in which the spatially inhomogeneous
broadband field is assumed to be spatially coherent. A decrease in fluctuations is accompanied by an increase in the size
of speckles in the direction of dispersion, as well as along the beam axis. An interpretation of the found regularities is
given.
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