The noninvasive optical technique of dynamic light scattering (DLS) is routinely used to characterize dilute and transparent submicrometer 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. We present a model experiment to study flowing dispersions of polystyrene latex particles of varying sizes under varying flow conditions by using a newly developed fiber-optic DLS probe. A modified correlation function proposed in an earlier study is applied to the analysis of extracting the size and velocity of laminar flowing particulate dispersions. The complementary technique of laser Doppler velocimetry is also used to measure the speed of moving particles to confirm the DLS findings.
© 2006 Optical Society of America
Photon Correlation and Scattering
Original Manuscript: September 12, 2005
Manuscript Accepted: November 9, 2005
Vol. 1, Iss. 5 Virtual Journal for Biomedical Optics
Alfred B. Leung, Kwang I. Suh, and Rafat R. Ansari, "Particle-size and velocity measurements in flowing conditions using dynamic light scattering," Appl. Opt. 45, 2186-2190 (2006)