Numerical calculation and measurement for the focus field of concave spherical acoustic lens transducer

How to accurately calculate the sound field formed by acoustic lenses is an important basis for the design of acoustic lens transducers. The radiation sound field distribution of the physical model of acoustics lens is simulated by numerical methods, including the ray propagation method and the wave propagation method. The ray propagation method can only get the focal length without considering the wave characteristics property, while the wave propagation method takes into account the amplitude and phase factors of the wave, and by which the distribution of the whole sound field can be got. The relationship between the property of refractive wave and incident angle of incident wave is analyzed, and theoretical results of the distribution of the focal field are obtained. The actual sound field of the real transducer is measured by acoustic field scanning system, and the measured results of focal length and focal area are obtained. The comparison and analysis of the numerical data and measured data show that the wave propagation method can be used to predict the focus field of concave spherical acoustic lens transducer accurately and effectively