Spatial light-scattering analysis as a means of characterizing and classifying non-spherical particles

The manner in which a particle scatters incident light is a function of the particle's shape, its size, its structure and its orientation with respect to the illumination direction, as well as to the wavelength and polarization state of the light. The spatial intensity distribution of scattered light thus contains information by which the particle may often be classified or even identified. This paper briefly reviews the development of spatial light scattering analysis as an analytical and monitoring tool now finding application in areas as diverse as environmental monitoring, aerosol and hydrosol research, microbiology and fine-powder characterization. The paper concludes with a practical example of the use of spatial scattering analysis to achieve real-time discrimination of a specific particle type, namely airborne asbestos fibres.