Abstract

The wandering of laser beams, after crossing a thick layer of atmospheric turbulence along their paths, is theoretically and experimentally investigated. The correlation of the wandering of two beams is theoretically evaluated within the limits of the geometrical optics. For the sake of simplicity the beams are assumed to be parallel, and the path outside the layer is assumed to be free of turbulence. The wandering of a beam is described by fluctuations of the spot position in a plane normal to the propagation direction and located at the end of the path. Correlation and structure functions of horizontal and vertical components of the spot fluctuations are evaluated by using an anisotropic model of turbulence given by Beckman. The theoretical development of these functions requires evaluation of multiple integrals. The resulting correlation and structure functions are constituted by three terms, which put in evidence the role played by the thickness of the layer and by its position along the path.

© 1986 Optical Society of America