Abstract
In speckle velocimetry, Young's fringes observed during analysis of the multiple-exposure photographs of tracer particles seeding a fluid flow are embedded in a speckle noise that renders their analysis difficult. Some first- and second-order statistical properties of this speckle background are considered in this paper. A simple model shows that, because of the small and fluctuating number of scatterers contained in the probe beam, the intensity fluctuations are enhanced, leading to a contrast greater than one. The same model also shows that the speckle grains are not completely independent because of the existence of long-range intensity correlations.
© 1985 Optical Society of America
Full Article | PDF ArticleMore Like This
C. J. D. Pickering and N. A. Halliwell
J. Opt. Soc. Am. A 2(10) 1721-1724 (1985)
C. J. D. Pickering and N. A. Halliwell
J. Opt. Soc. Am. A 2(4) 610-615 (1985)
C. J. D. Pickering and N. A. Halliwell
Appl. Opt. 23(17) 2961-2969 (1984)