Fiber-optic microphone based on bionic silicon micro-electro-mechanical system diaphragm

The bionic sound detector based on the principle of Ormia ochracea fly’s coupled ears is a miniature directional microphone that sensitive to pressure gradient. In this work, silicon micro-electro-mechanical system diaphragm consisting two interconnected wings designed and prepared, fiber-optic Fabry-Pérot interferometric constructed using diaphragm, characteristics are studied theoretically experimentally. According simulation results, has vibration modes rocking bending, rocking-mode displacement amplitude at given depends frequency propagation direction incident wave, closer eigenfrequency mode frequency, greater is; changes with in three-dimensional space, resulting spindle-shaped distribution, long axis spindle parallel implying most wave propagating along diaphragm. resonance measured be slightly smaller than simulated value. output signal horizontal azimuth angle source, producing figure-8 polar pattern. A linear relationship between response obtained range 0° – ±60°, sensitivity 39.98 mV/(°).