Surface fluctuation spectroscopy: Comments on experimental technique and capillary ripple theory

Abstract

We comment on several aspects of the light scattering technology that have been developed in our laboratory. In particular we show that Shih’s [Rev. Sci. Instrum. 55, XXX (1984)] data is consistent once beam propagation is taken into account fully and a small error in the grating constants corrected. The result is that we can make a stronger statement concerning the correspondence between theory and experiment for both the center frequency and width of the spectrum of capillary wave fluctuations at the liquid/vapor interface. We discuss questions of optimal design of the optical system and detection system for these measurements. We collect a set of dimensionless groups that are useful for the design of experiments.