Fi̇ber-optik i̇nterferometrik akustik sensörün mekanik ve optik optimizasyonu

External cavity Fiber optic interferometric microphones have the potential to operate at the acustic impedance derived noise limit, with a noise floor close to 1uPa/sqrt(Hz). This can be achieved with careful optimization of both the mechanical and optical properties of such a sensor. We describe models for the acoustic-to-displacement and displacement-to-optical signal transduction in a Fabry-Perot (FP) type interferometric microphone. We present experimental results and fi nite element calculations to validate the models. Based on the models, requirements to achieve ultimate sensitivity and noise level in a FP microphone are discussed. Demonstration of a microphone with 30 dBA noise floor is presented using partially optimized membrane and interferometer.