We describe a new method for characterizing particles in turbid media by cross correlating the scattered intensity fluctuations at two nearby points in the far field. The cross-correlation function selectively emphasizes single scattering over multiple scattering. The usual dynamic light-scattering capability of inferring particle size from decay rate is thus extended to samples that are so turbid as to be visually opaque. The method relies on single-scattering speckle being physically larger than multiple-scattering speckle. With a suitable optical geometry to select nearby points in the far field or equivalently slightly different scattering wave vectors (of the same magnitude), the multiple-scattering contribution to the cross-correlation function may be reduced and in some cases rendered insignificant. Experimental results demonstrating the feasibility of this approach are presented. (C) 1997 Optical Society of America.
Meyer, William V.; Cannell, David S.; Smart, Anthony E.; Taylor, Thomas W.; and Tin, Padetha, "Multiple-Scattering Suppression by Cross Correlation" (1997). Physics Faculty Publications. 107.
Meyer, William V., David S. Cannell, Anthony E. Smart, Thomas W. Taylor, and Padetha Tin. "Multiple-Scattering Suppression by Cross Correlation." Applied Optics 36 (1997): 7551-7558.
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