T. Parameswaran et Dr. Snelling, ESTIMATION OF SPATIAL AVERAGING OF TEMPERATURES FROM COHERENT ANTI-STOKES-RAMAN SPECTROSCOPY, Applied optics, 35(27), 1996, pp. 5461-5464
Spatial averaging is a potential problem in the application of coheren
t anti-Stokes Raman spectroscopy (CARS) to combustion diagnostics when
varying temperatures and composition are present at spatial scales sm
aller than the typical 1-2-mm spatial resolution of CARS. The observed
CARS spectrum is then a mixture of the hot and cold components. We sh
ow that simulated, spatially averaged spectra, generated by the incohe
rent addition of intensities, can be significantly different from thos
e obtained by the coherent addition of the electric held amplitudes of
the component spectra. The analyses of these simulated, spatially ave
raged CARS spectra demonstrate that the use of theoretical CARS spectr
a, generated by the addition of intensities of the hot and cold compon
ents of a binary gas mixture, can lead to errors in the estimated flam
e temperatures. (C) 1996 Optical Society of America