Spectral Characterization of PVDF Sensor Designs for Acoustic Spectroscopy

TL;DR

This paper investigates how different PVDF sensor designs affect their spectral responsivity, revealing a trade-off between responsivity and flatness of frequency response crucial for ultrasonic sensing applications.

Contribution

It provides a spectral characterization of four PVDF sensor variants, linking sensor thickness to responsivity and frequency dependence, informing design choices.

Findings

Increased responsivity correlates with non-linear frequency dependence.

Thicker PVDF sensors exhibit higher responsivity but less flat spectral response.

Trade-offs between responsivity and spectral flatness are characterized.

Abstract

Polyvinylidene difluoride (PVDF) sensors are of interest to ultrasonic applications due to their high sensitivity and efficient acoustic coupling to the environment. PVDF sensors for scientific applications typically possess a flat frequency response to faithfully reproduce spectral components of an unknown source. However, in industrial sensing applications higher responsivity is desirable even at the cost of decreased flatness in the spectral responsivity. To better understand the trade-offs between intrinsic responsivity and spectral response we examine four PVDF sensor variants for spectral responsivity as a function of thickness and find that increased responsivity is correlated with a strong non-linear frequency dependence.