Elastic back-scattering patterns via particle surface roughness and orientation from single trapped airborne aerosol particles

Richard Fu, Chuji Wang, Olga Muñoz, Gorden Videen, Joshua L. Santarpia, Yong Le Pan

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

We demonstrate a method for simultaneously measuring the back-scattering patterns and images of single laser-trapped airborne aerosol particles. This arrangement allows us to observe how the back-scattering patterns change with particle size, shape, surface roughness, orientation, etc. The recoded scattering patterns cover the angular ranges of θ=167.7–180° (including at 180° exactly) and ϕ=0–360° in spherical coordinates. The patterns show that the width of the average speckle intensity islands or rings is inversely proportional to particle size and how the shape of these intensity rings or islands also depends on the surface roughness. For an irregularly shaped particle with substantial roughness, the back-scattering patterns are formed with speckle intensity islands, the size and orientations of these islands depend more on the overall particle size and orientation, but have less relevance to the fine alteration of the surface structure and shapes. The back-scattering intensity at 180° is very sensitive to the particle parameters. It can change from a maximum to a minimum with a change of 0.1% in particle size or refractive index. The method has potential use in characterizing airborne aerosol particles, and may be used to provide back-scattering information for LIDAR applications.

Original languageEnglish (US)
Pages (from-to)224-231
Number of pages8
JournalJournal of Quantitative Spectroscopy and Radiative Transfer
Volume187
DOIs
StatePublished - Jan 1 2017

Fingerprint

Aerosols
aerosols
surface roughness
Surface roughness
Scattering
Particle size
scattering
Speckle
Surface structure
spherical coordinates
rings
Refractive index
roughness
Lasers
refractivity
lasers

Keywords

  • Elastic backscattering pattern
  • Image monitoring
  • Laser trapping
  • Single airborne particle
  • Surface roughness

ASJC Scopus subject areas

  • Radiation
  • Atomic and Molecular Physics, and Optics
  • Spectroscopy

Cite this

Elastic back-scattering patterns via particle surface roughness and orientation from single trapped airborne aerosol particles. / Fu, Richard; Wang, Chuji; Muñoz, Olga; Videen, Gorden; Santarpia, Joshua L.; Pan, Yong Le.

In: Journal of Quantitative Spectroscopy and Radiative Transfer, Vol. 187, 01.01.2017, p. 224-231.

Research output: Contribution to journalArticle

@article{f137dc5367ef4de3b6ed78e4472e3990,
title = "Elastic back-scattering patterns via particle surface roughness and orientation from single trapped airborne aerosol particles",
abstract = "We demonstrate a method for simultaneously measuring the back-scattering patterns and images of single laser-trapped airborne aerosol particles. This arrangement allows us to observe how the back-scattering patterns change with particle size, shape, surface roughness, orientation, etc. The recoded scattering patterns cover the angular ranges of θ=167.7–180° (including at 180° exactly) and ϕ=0–360° in spherical coordinates. The patterns show that the width of the average speckle intensity islands or rings is inversely proportional to particle size and how the shape of these intensity rings or islands also depends on the surface roughness. For an irregularly shaped particle with substantial roughness, the back-scattering patterns are formed with speckle intensity islands, the size and orientations of these islands depend more on the overall particle size and orientation, but have less relevance to the fine alteration of the surface structure and shapes. The back-scattering intensity at 180° is very sensitive to the particle parameters. It can change from a maximum to a minimum with a change of 0.1{\%} in particle size or refractive index. The method has potential use in characterizing airborne aerosol particles, and may be used to provide back-scattering information for LIDAR applications.",
keywords = "Elastic backscattering pattern, Image monitoring, Laser trapping, Single airborne particle, Surface roughness",
author = "Richard Fu and Chuji Wang and Olga Mu{\~n}oz and Gorden Videen and Santarpia, {Joshua L.} and Pan, {Yong Le}",
year = "2017",
month = "1",
day = "1",
doi = "10.1016/j.jqsrt.2016.09.018",
language = "English (US)",
volume = "187",
pages = "224--231",
journal = "Journal of Quantitative Spectroscopy and Radiative Transfer",
issn = "0022-4073",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Elastic back-scattering patterns via particle surface roughness and orientation from single trapped airborne aerosol particles

AU - Fu, Richard

AU - Wang, Chuji

AU - Muñoz, Olga

AU - Videen, Gorden

AU - Santarpia, Joshua L.

AU - Pan, Yong Le

PY - 2017/1/1

Y1 - 2017/1/1

N2 - We demonstrate a method for simultaneously measuring the back-scattering patterns and images of single laser-trapped airborne aerosol particles. This arrangement allows us to observe how the back-scattering patterns change with particle size, shape, surface roughness, orientation, etc. The recoded scattering patterns cover the angular ranges of θ=167.7–180° (including at 180° exactly) and ϕ=0–360° in spherical coordinates. The patterns show that the width of the average speckle intensity islands or rings is inversely proportional to particle size and how the shape of these intensity rings or islands also depends on the surface roughness. For an irregularly shaped particle with substantial roughness, the back-scattering patterns are formed with speckle intensity islands, the size and orientations of these islands depend more on the overall particle size and orientation, but have less relevance to the fine alteration of the surface structure and shapes. The back-scattering intensity at 180° is very sensitive to the particle parameters. It can change from a maximum to a minimum with a change of 0.1% in particle size or refractive index. The method has potential use in characterizing airborne aerosol particles, and may be used to provide back-scattering information for LIDAR applications.

AB - We demonstrate a method for simultaneously measuring the back-scattering patterns and images of single laser-trapped airborne aerosol particles. This arrangement allows us to observe how the back-scattering patterns change with particle size, shape, surface roughness, orientation, etc. The recoded scattering patterns cover the angular ranges of θ=167.7–180° (including at 180° exactly) and ϕ=0–360° in spherical coordinates. The patterns show that the width of the average speckle intensity islands or rings is inversely proportional to particle size and how the shape of these intensity rings or islands also depends on the surface roughness. For an irregularly shaped particle with substantial roughness, the back-scattering patterns are formed with speckle intensity islands, the size and orientations of these islands depend more on the overall particle size and orientation, but have less relevance to the fine alteration of the surface structure and shapes. The back-scattering intensity at 180° is very sensitive to the particle parameters. It can change from a maximum to a minimum with a change of 0.1% in particle size or refractive index. The method has potential use in characterizing airborne aerosol particles, and may be used to provide back-scattering information for LIDAR applications.

KW - Elastic backscattering pattern

KW - Image monitoring

KW - Laser trapping

KW - Single airborne particle

KW - Surface roughness

UR - http://www.scopus.com/inward/record.url?scp=84991704681&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84991704681&partnerID=8YFLogxK

U2 - 10.1016/j.jqsrt.2016.09.018

DO - 10.1016/j.jqsrt.2016.09.018

M3 - Article

AN - SCOPUS:84991704681

VL - 187

SP - 224

EP - 231

JO - Journal of Quantitative Spectroscopy and Radiative Transfer

JF - Journal of Quantitative Spectroscopy and Radiative Transfer

SN - 0022-4073

ER -