All-optical low noise fiber Bragg grating microphone

作者：Bandutunga Chathura P^*; Fleddermann Roland; Gray Malcolm B; Close John D; Chow Jong H

来源：Applied Optics, 2016, 55(21): 5570-5574.

DOI：10.1364/AO.55.005570

We present an all-fiber design for a microphone using a fiber Bragg grating Fabry-Perot resonator attached to a diaphragm transducer. We analytically model and verify the fiber-diaphragm mechanical interaction, using the Hansch-Couillaud readout technique to provide necessary sensitivity. We achieved a noise-equivalent strain sensitivity of 7.1 x 10(-12) epsilon/root Hz, which corresponds to a sound pressure of 74 mu Pa/root Hz at 1 kHz limited by laser frequency noise and yielding a signal-to-noise ratio of 47 +/- 2 dB with a 1 Pa drive at 1 kHz, in close agreement with modeled results.

• 出版日期2016-7-20