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Updated: May 12, 2026

A Stable Phantom Material for Optical and Acoustic Imaging
Published on: June 16, 2023
Sensing the characteristic acoustic impedance of a fluid utilizing acoustic pressure waves
Hannes Antlinger1, Stefan Clara, Roman Beigelbeck
1Institute for Microelectronics and Microsensors, Johannes Kepler University Linz, Altenberger Str. 69, A-4040 Linz, Austria.
Abstract:
Ultrasonic sensors can be used to determine physical fluid parameters like viscosity, density, and speed of sound. In this contribution, we present the concept for an integrated sensor utilizing pressure waves to sense the characteristic acoustic impedance of a fluid. We note that the basic setup generally allows to determine the longitudinal viscosity and the speed of sound if it is operated in a resonant mode as will be discussed elsewhere. In this contribution, we particularly focus on a modified setup where interferences are suppressed by introducing a wedge reflector. This enables sensing of the liquid's characteristic acoustic impedance, which can serve as parameter in condition monitoring applications. We present a device model, experimental results and their evaluation.
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