Open AccessTransparency effects on powder speckle decorrelation
Author(s) -
David L. Death,
John E. Eberhardt,
Craig A. Rogers
Publication year - 2000
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.6.000202
Subject(s) - decorrelation , speckle pattern , materials science , opacity , optics , surface finish , monte carlo method , surface roughness , scattering , composite material , physics , statistics , mathematics
Laser speckle decorrelation has previously been applied to measure the mean powder size of bulk powder beds and the roughness of porous rocks. The angular decorrelation rate of laser speckle from bulk powder beds correlates strongly with the mean powder size. However it was found that the angular decorrelation rates of transparent powders were much higher than those of opaque or dyed powders of the same size distribution. The accuracy of size measurements could be severely compromised if transparency effects were not compensated. Monte Carlo modelling of remitted photon path lengths in a powder bed suggests and experimental data supports that diffuse reflectance data may be used to correct for transparency effects on angular decorrelation rate data.