The non-invasive optical technique of dynamic light scattering (DLS) is routinely used to characterize dilute and transparent sub-micron particle dispersions in laboratory environments. A variety of industrial and biological applications would however greatly benefit from on-line monitoring of dispersions under flowing conditions. In this paper we present a model experiment to study flowing dispersions of polystyrene latex particles of varying sizes under varying flow conditions using a newly developed fiber optic DLS probe. A modified correlation function proposed in an earlier study by Chowdhury et al. is applied to the analysis of extracting size and velocity of laminar flowing particulate dispersions. The complimentary technique of laser Doppler velocimetry is also used to measure the speed of moving particles to confirm the DLS findings.
A preliminary study of corneal abnormalities in intact bovine eyes is presented. Twenty-one eyes were treated with chemicals, cotton swabs, and radial and photo-refractive surgeries. Dynamic and static light scattering was performed as a function of the penetration depth into the corneal tissue. Topographical maps of corneal refractive power from untreated and treated corneas were also obtained using videokeratoscopy and results compared. The ultimate aim is to develop the technique of dynamic light scattering (DLS) for clinical applications in early evaluation of corneal complications after laser-assisted in situ keratomileusis (LASIK) surgeries and other corneal abnormalities.