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Abstract

Although a remarkable signal-processing evolution has been going on in the sonograph, a more silent revolution has been going on within the scanhead with the development of composite multielement transducers (CMETs). This article examines the current state of CMET development and explores what these changes mean to basic beam formation and focusing. The discussion reveals some of the technologies that are part of contemporary CMET design, including transducer poling, connectivity, and coupling. In addition, this discussion includes some quality assurance (QA) techniques that can test these new transducers for proper function and determine what is happening beneath the scanhead housing. Finally, the authors propose a list of measurements needed to test CMETs, including element sensitivity, element center operating frequency, element fractional bandwidth, pulse shape, pulse duration, and element and cable capacitance, and they provide a QA testing protocol for the CMET.

Keywords

ultrasound transducer multielement composite quality assurance poling connectivity coupling beam forming beam steering

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The Silent Revolution

Abstract

Keywords

References