Archives of Acoustics, 45, 4, pp. 699–707, 2020

Optimal Selection of Multicomponent Matching Layers for Piezoelectric Transducers using Genetic Algorithm

Tadeusz GUDRA
Wrocław University of Science and Technology

Wrocław University of Science and Technology

One major problem in the design of ultrasonic transducers results from a huge impedance mismatch between piezoelectric ceramics and the loading medium (e.g. gaseous, liquid, and biological media). Solving this problem requires the use of a matching layer (or layers). Optimal selection of materials functioning as matching layers for piezoelectric transducers used in transmitting and receiving ultrasound waves strictly depends on the type of the medium receiving the ultrasound energy. Several methods allow optimal selection of materials used as matching layers. When using a single matching layer, its impedance can be calculated on the basis of the Chebyshev, DeSilets or Souquet criteria. In the general case, the typically applied methods use an analogy to a transmission line in order to calculate the transmission coefficient T. This paper presents an extension of transmission coefficient calculations with additional regard to the attenuation coefficients of particular layers. The transmission coefficient T is optimised on the basis of a genetic algorithm method. The obtained results indicate a significant divergence between the classical calculation methods and the genetic algorithm method.
Keywords: acoustic impedance; matching layers; ultrasonic transducers
Full Text: PDF
Copyright © The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0).


DeSilets C.S., Fraser J.D., Kino G.S. (1978), The design of efficient broad-band piezo¬electric transducers, IEEE Transactions on Sonics and Ultrasonics, 25(3): 115 125, doi: 10.1109/T-SU.1978.31001.

Fang H.J. et al. (2016), Anodic aluminum oxide–epoxy composite acoustic matching layers for ultrasonic transducer application, Ultrasonics, 70: 29 33, doi: 10.1016/j.ultras.2016.04.003.

Goll J.H. (1979), The design of broadband fluid-loaded ultrasonic transducers, IEEE Transactions on Sonics and Ultrasonics, 26(6): 385 393, doi: 10.1109/T-SU.1979.31122.

Gomez Alvarez Arenas T.E.G. (2004), Acoustic impedance matching of piezoelectric transducers to the air, IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 51(5): 624 633, doi: 10.1109/TUFFC.2004.1320834.

Gudra T., Opielinski K.J. (2002), Influence of acoustic impedance of multilayer acoustic system on the transfer function of ultrasonic airborne transducer, Ultrasonics, 40(1–8): 457 463, doi: 10.1016/S0041-624X(02)00159-2.

Hamidimioglu B., Khuri Yakub B.T. (1990), Polymers films as acoustic matching layers, IEEE Symposium on Ultrasonics, Honolulu, HI, USA, Vol. 3, pp. 1337–1340, doi: 10.1109/ULTSYM.1990.171581.

Hung B.H., Goldstein A. (1983), Acoustic parameters of comercial plastics, IEEE Transactions on Sonics and Ultrasonics, 30(4): 249 254, doi: 10.1109/T-SU.1983.31415.

Ilham H.M., Salim M.N., Jenal R.B., Hayashi T. (2016), Guided wave matching layer using a quarter of wavelength technique, Applied Mechanics and Materials, 833: 59 68, doi: 10.4028/

Lynworth L.C. (1965), Ultrasonic impedance matching from solids to gases, IEEE Transactions on Sonics and Ultrasonics, 12(2): 37 48, doi: 10.1109/T-SU.1965.29359.

Łypacewicz G., Duriasz E. (1992), Design principles of transducers with matching layers base on admittance measurements, Archives of Acoustics, 17(1): 117 131.

Nakamura K. et al. (2012), Ultrasonic transducers. Materials and design for sensors, actuators, and medical applications, Woodhead Publishing Series in Electronic and Optical Materials: Number 29, Elsevier, pp. 185 219, 374 407.

Onda Corporation (2003), Tables of Acoustic Properties of Materials, USA, (accessed on 10 January 2020).

Pedersen P.C., Tretiak P., He P. (1982), Impedance – matching properties of an inhomogeneous matching layer with continuously changing acoustic impedance, The Journal of the Acoustical Society of America, 72(2) 327 338, doi: 10.1121/1.388085.

Qian Y., Harris N. R. (2014), Modelling of a novel high-impedance matching layer for high frequency (> 30 MHz) ultrasonic transducers, Ultrasonics, 54(2): 586 591, doi: 10.1016/j.ultras.2013.08.012.

Rhee S., Ritter T.A., Shung K.K., Wang H., Cao W. (2001), Materials for acoustic matching in ultrasound transducers, 2001 IEEE Ultrasonics Symposium. Proceedings. An International Symposium (Cat. No.01CH37263), Atlanta, GA, USA, 2001, Vol. 2, pp. 1051–1055, doi: 10.1109/ULTSYM.2001.991900.

Saffar S., Abdullah A. (2012), Determination of acoustic impedances of multi matching layers for narrow band transmitter ultrasonic airborne transduces with frequencies < 2.5 MHz – application of a genetic algorithm, Ultrasonics, 52(1): 169 185, doi: 10.1016/j.ultras.2011.08.001.

Saffar S., Abdullah A., Othman R. (2014), Influence of the thickness of matching layers on narrow band transmitter ultrasonic airborne transducers with frequencies < 100 kHz: Application of a genetic algorithm, Applied Acoustics, 75: 72 85, doi: 10.1016/j.apacoust.2013.07.002.

Souquet J., Defranoud P.H., Desbois J. (1979), Design of low loss wide band ultrasonic transducers for noninvasive medical applications, IEEE Transactions on Sonics and Ultrasonics, 26(2): 75 81, doi: 10.1109/T-SU.1979.31070.

Thomson W.T. (1950), Transmission of elastic waves through a stratified solid medium, Journal of Applied Physics, 21(2): 89–93, doi: 10.1063/1.1699629.

Toda M., Thompson M. (2010), Novel multi-layer polimer-metal structures for use in ultrasonic transducer impedance matching and backing absorber applications, IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 57(12): 2818 2827, doi: 10.1109/TUFFC.2010.1755.

Toda M., Thompson M. (2012), Detailed investigations of polymer/metal multilayer matching layer and backing absorber structures for wideband ultrasonic transducers, IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 59(2): 231 242, doi: 10.1109/TUFFC.2012.2183.

Trogé A., O’Leary R.L., Hayward G., Pethrick R.A., Mullholland A.J. (2010), Properties of photocured epoxy resin materials for application in piezoelectric ultrasonic transducer matching layers, The Journal of the Acoustical Society of America, 128(5): 2704 2714, doi: 10.1121/1.3483734.

Wang Y. et al. (2018), Magnesium alloy matching layer for high-performance transducer applications, Sensors, 18(12): 4424, doi: /10.3390/s18124424.

DOI: 10.24425/aoa.2020.135276