Abstract

A laser beam was passed through a turbulent mixture of hot and cold water. The optical path contained no solid scattering particles. It was, therefore, similar to an atmospheric path containing only clear-air turbulence. The field irradiance was accurately described by a truncated three-parameter log-normal probability density. The statistics of the integral of the field irradiance over an area comparable in size to one coherence area was also always characterized by a three-parameter log-normal density. This probability density, when used in the Mandel formula for the single-photon-counting probability, correctly predicted the observed results. The parameters of the irradiance density could be varied by changing the temperature of the hot- and cold-water mixture, or the position of the optical path. The observed photon-counting probabilities could not be obtained by use of a two-parameter log-normal irradiance density (more commonly called the log-normal density) in the Mandel formula.

© 1975 Optical Society of America

Are Strong Irradiance Fluctuations Log Normal or Rayleigh Distributed?*

David A. de Wolf
J. Opt. Soc. Am. 59(11) 1455-1460 (1969)

Perturbed log-normal distribution of irradiance fluctuations*

Ting-i Wang and John W. Strohbehn
J. Opt. Soc. Am. 64(7) 994-999 (1974)

Photon-Count Distributions and Irradiance Fluctuations of a Log-Normally Distributed Light Field*

Van Bluemel, Lorenzo M. Narducci, and Richard A. Tuft
J. Opt. Soc. Am. 62(11) 1309-1314 (1972)

Permanence of the Log-Normal Distribution*

R. L. Mitchell
J. Opt. Soc. Am. 58(9) 1267-1272 (1968)

Dead-time-corrected photocounting distributions for laser radiation*

B. I. Cantor and M. C. Teich
J. Opt. Soc. Am. 65(7) 786-791 (1975)