Observations of Acoustic Radiation Resulting from Incidence at the Critical Angles and the Rayleigh Angle for Plane Surfaces

Abstract

The resulting radiated field is observed by sehlieren methods for an ultrasonic beam generated in water incident on a solid interface. Radiation outside the specular region has been observed at the longitudinal and shear critical angles and at the Rayleigh angle. A periodic spatial variation in acoustic amplitude occurs in this radiated field at the Rayleigh angle. This effect will be discussed.