Three-dimensional forward scattering particle image velocimetry applied toa microscopic field-of-view

We have completed a model to predict the three-dimensional position of a sp herical particle from the image formed by a high numerical aperture microsc ope. Although this information may be exploited in a number of different wa ys, we are particularly interested in determining the three components of v elocity for seed particles following a flow. The basis of the model is to u se Mie theory to determine the complete electromagnetic field scattered by a spherical particle and then to propagate the scattered field across the i nterface between sample and air and then through a high aperture microscope and ultimately to a detector.