“…However, tuning of the light sources over a wide spectral range limits the time response of these techniques and also complicates the data analysis due to the variation of refractive index over wide ranges of wavelengths. Rapid and continuous measurement is highly desirable in many applications, such as the study of spray combustion (Grassmann & Peters, 2004;Meyer, Roy, Belovich, Corporan, & Gord, 2005;Tishkoff, Hammond, & Chraplyvy, 1982;Winklhofer & Plimon, 1991) and the fast formation/evaporation of aerosols (Vandongen, Smolders, Braun, Snoeijs, & Willems, 1994). Such measurement needs motivate the development of the second category of methods, which relies on scattering data at a single wavelength or a limited number of discrete wavelengths.…”