An optical fibre MEMS pressure sensor using dual-wavelength interrogation

A novel pressure sensor based on Fabry–Perot interferometry and micro-electromechanical systems (MEMS) technology is proposed and demonstrated. A basic, simplified micro-electromechanical technique is used to fabricate the pressure sensor, and the fabrication process and packaging configuration are outlined in this paper. The interference of multiple cavities as a whole is theoretically analysed and simulated. A dual-wavelength demodulation method, which can compensate the errors independent of optical wavelength, is used to demodulate the sensor by analysing the reflected optical signals. Experimental results demonstrate that the sensor has reasonable linearity, sensitivity and a wide pressure measurement range from 0.1 MPa to 3 MPa.