Abstract

A nonlinear overestimate of the median droplet diameter measured by laser diffractometry in aerosols of interest in atomic spectrochemical analysis is found to result if the aerosol path traversed by the laser exceeds the optical depth of field characteristic of the diffractometer. The depth of field of a Leeds and Northrup diffractometer is found to be 4.4 cm. The magnitude of the error in apparent median droplet diameter is +21% for aerosols emergent from 10 cm slot burners used in flame spectrochemical analysis. Additional data are included for a variety of aerosol path lengths over the range 0.5 to 20 cm. Although a nonlinear overestimate in median diameter results from use of aerosol path lengths exceeding the optical depth of field (4.4 cm), no appreciable change in the width of the apparent droplet size distribution was found to occur for path lengths up to 18 cm.

Optical diffractometry

M. Taghi Tavassoly, Mohammad Amiri, Ahmad Darudi, Rasoul Aalipour, Ahad Saber, and Ali-Reza Moradi
J. Opt. Soc. Am. A 26(3) 540-547 (2009)

Standoff determination of the particle size and concentration of small optical depth clouds based on double scattering measurements: concept and experimental validation with bioaerosols

Gilles Roy and Nathalie Roy
Appl. Opt. 47(9) 1336-1349 (2008)

Focused laser beam effects in optical particle sizing by dynamic light scattering

Douglas A. Ross
Appl. Opt. 30(33) 4882-4888 (1991)

Beam stop and vignetting effects in particle size measurements by laser diffraction

Peter N. Wild and Joshua Swithenbank
Appl. Opt. 25(19) 3520-3526 (1986)

Quantum electrodynamics analysis of optical binding in counterpropagating beams and effect of particle size

Justo Rodriguez
Opt. Lett. 33(19) 2197-2199 (2008)