Ultrasonic transducers which include at least one internally directed generally concavely configured sonic energy radiating element which directs sonic energy toward at least one arcuate energy reflecting surface which redirects and focuses the energy through an opening in a housing defining the transducer. The configuration of the at least one radiating element and the at least one energy reflecting surface are such that sound waves from substantially any point along the radiating element to the reflecting surface and to a focus exteriorly of the opening are substantially equal. The transducers function to focus energy either as transmitters or receivers.