Center for Optics Research and Engineering, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
Sensors (Basel). 2023 Mar 24;23(7):3444. doi: 10.3390/s23073444.
A resonant acoustic wave detector combined with Fabry-Pérot interference (FPI) and piezoelectric (PE) effects based on a polyvinylidene fluoride (PVDF) piezoelectric film was proposed to enhance the ability of the sensor to detect acoustic signals in a specific frequency band. The deformation of circular thin films was indicated by the interference and piezoelectric effects simultaneously, and the noise level was decreased by the real-time convolution of the two-way parallel signal. This study reveals that, at the film's resonance frequency, the minimum detection limits for the FPI and piezoelectric impacts on acoustic waves are 3.39 μPa/Hz and 20.8 μPa/Hz, respectively. The convolution result shows that the background noise was reduced by 98.81% concerning the piezoelectric signal, and by 85.21% concerning the FPI signal. The convolution's signal-to-noise ratio (SNR) was several times greater than the other two signals at 10 mPa. Therefore, this resonance sensor, which the FPI and the piezoelectric effect synergistically enhance, can be applied to scenarios of acoustic wave detection in a specific frequency band and with ultrahigh sensitivity requirements.
提出了一种基于聚偏二氟乙烯（PVDF）压电薄膜的共振声波探测器，结合了法布里-珀罗干涉（FPI）和压电（PE）效应，以增强传感器在特定频带中检测声信号的能力。圆形薄膜的变形同时通过干涉和压电效应来指示，并且通过两路平行信号的实时卷积来降低噪声水平。这项研究表明，在薄膜的共振频率下，FPI 和压电对声波的最小检测极限分别为 3.39 μPa/Hz 和 20.8 μPa/Hz。卷积结果表明，与压电信号相比，背景噪声降低了 98.81%，与 FPI 信号相比，背景噪声降低了 85.21%。在 10 mPa 时，卷积的信噪比（SNR）比其他两个信号高几倍。因此，这种共振传感器可以应用于特定频带和超高灵敏度要求的声波检测场景，FPI 和压电效应协同增强。
