Conversion relationships for multidimensional particle sizing techniques

Abstract

In recent years two out-of-focus techniques have been introduced for sizing sphericalparticles within a two- or three-dimensional domain. The first of these, interferometricparticle imaging, has recently been commercialized under various names. The secondtechnique, global phase Doppler, employs two illuminating light sheets and is closelyrelated to the well-known phase Doppler technique.Each of these techniques results in an image in which the spacing or number of interferencefringes must be related to the particle size through a conversion relationship. Thederivation of these relationships has not been well documented to date and insome cases falsely reported in the literature. The present paper provides thesederivations, their range of validity and some additional results for specific situations.