Ultrasound fields from triangular apertures

The pulsed field from a triangular aperture mounted in an infinite, rigid baffle is calculated. The approach of spatial impulse responses, as developed by Tupholme and Stepanishen, is used. By this both the emitted and received pulsed ultrasound field can be found for any transducer excitation and electromechanical impulse response. The continuous wave field is also readily obtainable through a simple Fourier transform. The spatial impulse response is calculated without approximation, and the solution is valid in the half-space in front of the aperture for a homogeneous, nonattenuating medium. The solution can be used in finite element programs for calculating fields from arbitrary transducer geometries. (C) 1996 Acoustical Society of America.