MEMS-based Optic Fiber Fabry-Perot Sensor for Underwater Acoustic Measurement with A Wavelength-switched System

[摘要] In this paper, a MEMS-based extrinsic Farby-Perot Interferometric (EFPI) acoustic pressure acoustic sensor is presented. The diaphragm structure is used as the second reflected surface, and the sensitive surface to acoustic pressure. A wavelength-switched phase demodulation system for EFPI sensors is used for acoustic signal recovery. The modified phase demodulation system has been demonstrated to recover the signal to a stable intensity fluctuation level of ±0.5 dB at the test frequency of 2000 Hz. In the test depth of 50cm, the sensor has a resonant frequency of 3.7 kHz, a flat frequency range of 10-800Hz, and a corresponding acoustic pressure sensitivity of -159 dB re. 1/μPa.

[发布机构] Academy of Ocean Science and Engineering, National University of Defense Technology, Changsha; 410073, China^1;College of Optics Science and Engineering, National University of Defense Technology, Changsha; 410073, China^2

[效力级别] 机械制造 [学科分类] 材料科学（综合）

[关键词] Acoustic measurements;Acoustic pressures;Acoustic Sensors;Frequency ranges;Intensity fluctuations;Phase demodulation;Test frequencies;Wavelength-switched