Efficiency of Ultrasonic Comb Transducers

Abstract

Comb transducers are applied in ultrasonic testing for generation of Rayleigh or Lamb waves by scattering of the incident bulk waves onto surface waves at the pe- riodic comb-substrate interface. Hence the transduction efficiency, although rarely discussed in literature, is an important factor for applications determining the qual- ity of the measured ultrasonic signals. This paper presents the full-wave theory of comb transducers concluded by evaluation of their efficiency for a couple of examples of standard and certain novel configurations.