Abstract

We demonstrate a method for measuring elastic back-scattering patterns from single laser trapped micron-sized particles, spanning the scattering angle range of $\mathit{\theta }=167.7°–180°$ and $\phi =0°–360°$ in spherical coordinates. We calibrated the apparatus by capturing light-scattering patterns of 10 μm diameter borosilicate glass microspheres and comparing their scattered intensities with Lorenz–Mie theory. Back-scattering patterns are also presented from a single trapped Johnson grass spore, two attached Johnson grass spores, and a cluster of Johnson grass spores. The method has potential use in characterizing airborne aerosol particles, and may be used to provide back-scattering data for lidar applications.

Characterizing and monitoring respiratory aerosols by light scattering

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Detection and characterization of chemical aerosol using laser-trapping single-particle Raman spectroscopy

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Characterization of single airborne particle extinction using the tunable optical trap-cavity ringdown spectroscopy (OT-CRDS) in the UV

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Opt. Express 20(5) 5325-5334 (2012)

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