
Accession Number : AD0741677
Title : A Perturbative Treatment of Thermal Blooming in Pulsed Laser Beams.
Descriptive Note : Interim rept.,
Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C
Personal Author(s) : Aitken,Alfred H.
Report Date : 18 APR 1972
Pagination or Media Count : 34
Abstract : The atmospheric propagation of pulsed, focussed, laser beams is calculated. The beam intensity is obtained by solving the equation of geometric optics and the equation of energy conservation simultaneously using a perturbative scheme. In this way the modification on propagation due to change caused by the index of refraction absorption of energy from the beam itself is included in a linear approximation. The problem of calculating the index of refraction change in a quiescent atmosphere is formulated generally with detailed expressions, valid for all times, given for the case of a paraxial Gaussian beam. Formulas for beam intensity are given as graphical results presented for the onaxis intensity of a focussed Gaussian beam. (Author)
Descriptors : (*COHERENT RADIATION, ATMOSPHERES), PROPAGATION, LIGHT TRANSMISSION, REFRACTIVE INDEX, INTENSITY, HYDRODYNAMICS, MATHEMATICAL MODELS
Subject Categories : Atmospheric Physics
Lasers and Masers
Distribution Statement : APPROVED FOR PUBLIC RELEASE