Stability-enhanced low-frequency fiber optic hydrophone based on an extrinsic Fabry-Perot interferometer
Qing Zuo, Yuxiang Wang, Dinghan Li, Song Chen, Y. Y. Guo, Haifeng Qiao, Hao Wang, Rui Tu, Xin Tu, Wei Luo
Abstract
Fiber optic hydrophones (FOHs) offer the notable advantage of electromagnetic interference resistance. Nevertheless, overcoming the challenge of sustaining stable, high-performance operation in intricate underwater settings at a low cost remains a considerable obstacle for them. To circumvent the restrictions noted above, we employed a miniaturized FOH, utilizing an easily fabricated extrinsic Fabry-Perot interferometer (EFPI) which is made up of a composite chromium-aluminum (Cr-Al) membrane and fiber. The linear demodulation also suppresses the drift issue in the output spectrum. The average sound pressure sensitivity of the sensor, according to experimental findings, is around -139.15 dB re 1 V/µPa, while the equivalent noise sound pressure at 1 kHz is 51.52 dB re 1 µPa/Hz 1/2 . This sensor has a lot of potential because of features like sensitive low-frequency response and noise performance.