Acoustic analysis of ultrasonic air-borne transducer with concave structure

Abstract

This paper introduces an ultrasonic transducer with a concave curved structure. The transducer is based on a concave piezoelectric film on a silicone support with an air cavity. Specifically, an air cavity exists between the piezoelectric film and the support in the shape of a curved cuboid, providing space for the film to vibrate. We build a theoretical model of a concave piezoelectric transducer. To validate the model, we demonstrate a concave piezoelectric transducer and measure the ultrasound pressure field using an acoustic imaging camera. Two types of experiments are conducted by supplying a sinusoidal input voltage with a frequency sweep and a voltage sweep. The experimental results share similarity with the theoretical results. In addition, we conduct a parametric study to analyze the characteristics of the transducer. Interestingly, we find that the radius of curvature and axial length primarily contribute to ultrasound pressure.