Measurements of light scattering in an integrated microfluidic waveguide cytometer.

An integrated microfluidic planar optical waveguide system for measuring light scattered from a single scatterer is described. This system is used to obtain 2D side-scatter patterns from single polysty- rene microbeads in a fluidic flow. Vertical fringes in the 2D scatter patterns are used to infer the location of the 90-deg scatter polar angle. The 2D scatter patterns are shown to be symmetrical about the azimuth angle at 90 deg. Wide-angle comparisons between the ex- perimental scatter patterns and Mie theory simulations are shown to be in good agreement. A method based on the Fourier transform analysis of the experimental and Mie simulation scatter patterns is developed for size differentiation. © 2008 Society of Photo-Optical Instrumenta-