A Perturbative Treatment of Thermal Blooming in Pulsed Laser Beams.
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 on-axis intensity of a focussed Gaussian beam. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 18, 1972
- Accession Number
- AD0741677
Entities
People
- Alfred H. Aitken
Organizations
- United States Naval Research Laboratory