Comparison of Scattering Amplitudes from Various Transducers Using Diffraction and Attenuation Corrections

Abstract

<p>As a part of a project to develop an ultrasonic multiviewing transducer which is capable of providing sufficient information for flaw reconstruction, results have been obtained that address certain phases of the required signal processing routine. It is well known that individual ultrasonic transducers show a considerable variation in signal responses. Inasmuch as the multiviewing transducer uses a sparse array of individual transducers arranged in a particular geometry, it becomes important that signal processing routines be developed and applied which overcome these variabilities. There are, of course, several possible sources of variability in transducer performance. These include those of measurement (diffraction, attenuation and effects associated with imperfect deconvolution processes), and those due to fabrication (transducer design, materials, reproducibility of fabrication techniques, etc.). The results presented in this paper address only the former of these two. In particular, they represent a limited experimental assessment of the adequacy of specific data processing procedures for three different transducers and three different samples utilizing Weiner filter concepts and diffraction and attenuation corrections. Use is made of theoretical curves for scattering amplitude as an absolute standard of comparison and therefore as the criterion of adequacy.</p>