New design of matching layers for high power and wide band ultrasonic transducers

Abstract

Application fields of ultrasonic transducers can be divided into two categories, a high resolution required field and a high power required field. This paper's aim is to determine optimal properties of the matching layers of the transducer for each of the applications. Furthermore, its goal is to optimize the properties of the matching layers that show satisfactory performance for both of the application fields. Through the direct time domain analysis of the transmission and reflection behavior of the ultrasonic wave, apart from the conventional equivalent circuit analysis, and Fourier transformation of its results, we find the optimum acoustic impedance of the matching layers. The newly determined layers provide much better transducer performance—up to 57% more—than those obtained with conventional design methods. For the optimization, we have developed a new transducer performance evaluation parameter that can be applied to any type of ultrasonic transducers.