Noninvasive measurement of surface tension and viscosity with fiber optic light-scattering spectrometer

Traditional methods of measuring surface tension and viscosity of liquid/vapor interface are invasive systems making unavoidable mechanical contact with the interface that is under investigation. We have demonstrated a complete fiber optics based heterodyne sensor system that non-invasively measures the interfacial surface tension and viscosity. Measured values from this complete fiber optics system for some simple liquid vapor interfaces give consistent values with established values obtained by other invasive methods.