Premium
Extinction by a Large Spherical Particle Located in a Narrow Gaussian Beam
Author(s) -
Shen Jianqi,
Riebel Ulrich
Publication year - 2001
Publication title -
particle and particle systems characterization
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.877
H-Index - 56
eISSN - 1521-4117
pISSN - 0934-0866
DOI - 10.1002/1521-4117(200112)18:5/6<254::aid-ppsc254>3.0.co;2-x
Subject(s) - extinction (optical mineralogy) , beam (structure) , particle (ecology) , optics , beam diameter , gaussian beam , beam parameter product , physics , laser beam quality , particle beam , laser , materials science , laser beams , geology , oceanography
In most extinction measurements, the laser beam is expanded and the particles are small enough so that the incident beam can be considered as a plane wave. With regard to particle size analysis by optical extinction counters or transmission fluctuation spectrometry, however, we are interested in the opposite situation, i.e. particle diameters which are larger than the beam diameter. This paper presents experimental results on the extinction by an absorbent or transparent spherical particle passing through a Gaussian beam. The experiments show that the extinction is sensitive to the particle location, especially when the particle is very near to the beam waist and the ratio of the beam to the particle diameter is close to or less than 1.