Simultaneous two-color, two-dimensional angular optical scattering patterns from airborne particulates: Scattering results and exploratory analysis

• Simultaneous acquisition of two-color, two-dimensional angular optical scattering from aerosols on a single camera.
• Pollen aerosols and spores were illuminated with red and green lasers to observe spectral effects on scattering.
• Novel morphological descriptors identified for use in classification routines.
• Preliminary classification analysis discriminates among several aerosol types using the new descriptors.
• Classification results demonstrate feasibility of this approach and data descriptors.

Light scattering from non-spherical particles and aggregates exhibits complex structure that is revealed only when observed in two angular dimensions (θ, ϕ). However, due to variations in shape, packing, and orientation of such aerosols, the structure of two-dimensional angular optical scattering (TAOS) patterns varies among particles. The spectral dependence of scattering contributes further to the observed complexity, but offers another facet to consider. By leveraging multispectral TAOS data from flowing aerosols, we have identified novel morphological descriptors that may be employed in multivariate statistical algorithms for “unknown” particle classification.