Measurements of elastic light-scattering patterns and images of single, oriented, optically yrapped particles

We demonstrate a method for recording 2D forward-scattering patterns from optically trapped single airborne particles at multiple angular orientations. We collected images of trapped particles simultaneously with their scattering patterns to observe changes in the patterns with orientation. We present measurements of particles with wide-ranging morphologies from nearly spherical to highly irregular and with various compositions. The highly irregularly shaped particles have scattering patterns with spots of high intensity whose locations change with particle orientation. Additionally, measurements of a manufactured polystyrene spheroid of a known size are compared with calculated diffraction patterns. Such controlled-orientation measurements have the potential to help develop algorithms to characterize airborne aerosol particles using morphological information inferred from remote-sensing or other elastic light scattering measurements. (C) 2022 Elsevier Ltd. All rights reserved.

Automated summary

This study demonstrates a method for recording 2D forward-scattering patterns of optically trapped single airborne particles at different angles. The measurements include particles with various morphologies and are compared with calculated diffraction patterns. The study has the potential to assist in characterizing airborne aerosol particles based on morphological information.