Multi-wavelength intensity-modulated optical fiber fabry-perot sensor high-speed measurement system

Abstract

The application claims a kind of multi-wavelength intensity modulation spectrum sampling fiber Fabry sensor high-speed measurement system, belongs to the field of fiber sensing technology.The system includes laser array, fiber coupler, fiber circulator, fiber Fabry-Perot (Fabry) interference sensor, photodetector, multiplex lock-in amplifier and computer;Method includes: using laser array, outputting multiple different wavelength lasers, and modulating each wavelength laser with different modulation frequency intensity modulation, transmitting to fiber Fabry sensor through fiber coupler and fiber circulator to interfere;S2: interference signal enters photodetector through fiber circulator, converts the interference signal output by fiber Fabry sensor into electrical signal;S3: multiplex lock-in amplifier separates different wavelength interference signals by different internal reference frequencies, and transmits them to computer;S4: after computer obtains the spectrum of interference signal, the cavity length of sensor is demodulated in real time using Fourier transform algorithm.The system has the advantages of high speed, high precision, high sensitivity and long-term stability.

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