Nozzles and nebulizers able to produce aerosol with optimum and
reproducible quality based on feedback information obtained using laser
imaging techniques. Two laser-based imaging techniques based on particle
image velocimetry (PTV) and optical patternation map and contrast size
and velocity distributions for indirect and direct pneumatic
nebulizations in plasma spectrometry. Two pulses from thin laser sheet
with known time difference illuminate droplets flow field. Charge coupled
device (CCL)) captures scattering of laser light from droplets, providing
two instantaneous particle images. Pointwise cross-correlation of
corresponding images yields two-dimensional velocity map of aerosol
velocity field. For droplet size distribution studies, solution is doped
with fluorescent dye and both laser induced florescence (LIF) and Mie
scattering images are captured simultaneously by two CCDs with the same
field of view. Ratio of LIF/Mie images provides relative droplet size
information, then scaled by point calibration method via phase Doppler
particle analyzer.