Audio Directional Ultrasonic Transducer

Ultrasonic Audio Beam Transducer is a revolutionary way of projecting audio signal in a highly directional manner to the listener. Two modulated ultrasonic waves with difference frequency were emitted to the air by this new equipment. After nonlinear interaction, a high-directivity audio beam is developed which can generate beam of audio.The directivity of the Ultrasonic Audio Beam Transducer was studied in this paper. To determine the directivity of the beam, sound pressure of the transducer was calculated. The effect of structure and array pattern on the directivity was also studied. Some ultrasonic transducer are designed and fabricated. The experimental results shown that the proper structure and array pattern of the elements can lead to sharper directivityFive ultrasonic transducers were design and fabricated by using the Poly Vinylidene Fluoride (PVDF film) membrane, including: concavo-convex transducer which fabricated by the pressing method, concavo transducer which fabricated by high temperature method, circular transducer, the improved concavo-convex transducer and the improved concavo transducer which fabricated by the gluing methodThe free vibration characteristic of the circular transducer and the cylinder transducer were presented in this paper. The frequency response, sound pressure and the directivity of the cylinder transducer were also analysis based on the vibration with clamped conditions.The method for testing the resonance frequency, sound pressure and bean directivity were presented and the experimental system was also constructed in this paper. The resonance frequencies of the transducers were measured and the results shows that the free vibration theory could be used to determined the resonance frequency with clamped conditions. The directivity of the wave transducers were measured and the results shows that the wave transducer could generated audio beam with high directivity, it was feasible and reasonable to design the transducer based on the directivity theory, piezoelectric theory and fabrication method.