| The study of wave propagation through random media is important for measurements involving the atmosphere and for other environmental sensing applications. Of recent importance, is the study of near-IR light within biological tissue for imaging and spectroscopy, especially for tumor detection.; Highly coherent laser light propagating through a random medium accumulates a random phase due to the multiple scattering and forms an intensity speckle pattern when imaged. It is demonstrated experimentally that the statistical properties of the resultant speckle pattern enables the scattering properties of the random medium to be characterized. In particular, the key result of this study shows for the first time that third-order frequency correlations of a speckle pattern allow the temporal response of a random medium to be determined. The statistical properties of the speckle pattern are also sensitive to the coherence of the source and to any inhomogeneities within the random medium, thus providing potential for optical imaging. |
