Abstract
Scattering techniques can average over many more particles than can direct methods and thus often provide much better quantitative measurements of the average structural and dynamical properties of materials. Scattering techniques generally work best when the wavelength of the radiation is about the same as the size of the structures that scatter the radiation. The basic principle underlying light scattering can be grasped by considering the intensity of the light scattered by two particles within the scattering volume. Dynamic light scattering (DLS) takes note of particular fact and uses the time dependence of the flickering speckles to quantitatively characterize the underlying motion of the scatterers. Scattering methods based on imaging geometries have been developed, such as Photon Correlation Imaging and Near Field Scattering. In differential dynamic microscopy (DDM), one takes again advantage of a differential algorithm.