STATISTICAL APPROXIMATIONS IN STUDYING THE INTERACTION OF BROADBAND LASER RADIATION IN A COMPLEX ENVIRONMENT

 In this paper, statistical expressions describing the change in the degree of coherence of broadband laser radiation with an inclined coherence layer in a homogeneous medium are theoretically studied. The case of changes in the spatial coherence of intersecting broadband light beams with parallel layers of coherence is considered. An assessment of the region of coherent interaction for this case is given, and it is determined that the degree of coherence of a dispersed beam decreases noticeably faster with distance than in the case without the use of a dispersive element. Within the framework of the models used, it was found that the violation of coherence during the propagation of a light beam increases with increasing angle of inclination of the coherence layers. The possibility of significantly increasing the area of coherent interaction of intersecting beams as a result of tilting their coherence layers in such a way that by setting a certain value of the angle of their intersection it was possible to obtain parallelism of the coherence layers for them was also studied. In this case, restrictions on the transverse size of the overlapping beams are removed and it becomes possible to use the entire area of their overlap. A general scheme for constructing the asymptotics of the obtained analytical solutions was outlined. It is shown that the universal nature of asymptotic methods for calculating wave impulses can be supplemented with some universal heuristic conditions and criteria for the applicability of these methods. These criteria provide internal control over the applicability of the asymptotic methods used, and in a number of cases, based on the formulated criteria, it is possible to evaluate wave fields where these methods are not applicable. This opens up wide possibilities for analyzing wave patterns as a whole, which is important both for the correct formulation of theoretical studies and for carrying out evaluation calculations during experimental or field measurements of wave packets of laser radiation.

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