Diffusing Wave Spectroscopy
Diffusing Wave Spectroscopy (DWS) is an advanced light scattering technique, which is primarily applied for microrheology and particle sizing. Both applications utilize the capacity of DWS to extract the mean square displacement (MSD) of particles dispersed in a solvent from measurements of the temporal fluctuation of backscattered or transmitted light. The transmitted light intensity fluctuates over time, as shown by the evolving speckle pattern in the picture here above. This is a direct result of both the motion of the scattering particles within the sample and the coherent nature of the light.