Comparisons between geometrical optics and Lorenz-Mie theory.

Scattered light patterns produced by spherical transparent particles of a wide range of diameters (1-100 microm) and for a useful range of forward scattering angles (0-20 degrees ) are calculated by using both Lorenz-Mie theory and geometrical optics theory. A detailed comparison of the results leads to a definitive assessment of the accuracy of geometrical optics theory in the forward direction. Emphasis is put on simultaneous sizing and velocimetry of particles using pedestal calibration methods.