Abstract

We demonstrate the simultaneous use of the volume attenuation coefficient of a liquid acting upon a laser beam traversing the bulk liquid and the refraction of the beam as it traverses the air-liquid interface to obtain collocated and simultaneous measurements of surface elevation and slope at a point. Using optical imaging techniques for the one-dimensional case, real-time surface height profiles can be captured from which wave amplitude spectra are directly obtained. An example of the point measurement of elevation and slope of a water surface is shown in Fig. 1. Examples of the 1-D measurements of captured surface height profiles and their corresponding spectra are shown in Figs. 2 and 3.

© 1994 Optical Society of America