Temperature-compensated fiber-optic Fabry-Perot pressure sensor based on sapphire MEMS technology for high temperature environment up to 1500°C

A temperature-compensated fiber-optic Fabry-Perot pressure sensor based on sapphire micro-electro-mechanical systems (MEMS) technology for high temperature environment up to 1500 °C is proposed and demonstrated. Two Fabry-Perot cavities are fabricated through sapphire direct bonding, designed for the measurement of temperature and pressure, respectively. The integration of lens at the fiber-optic end-face, combined with a heat resistant package, allows for remote signal extracting. Experimental results show that it is capable of simultaneously measuring temperature and pressure within the working range of 25-1500 °C and 0-1 MPa. The resolution of the sensor is 0.1% F.S. and the high-temperature repeatability is 1.73% F.S. At 1500 °C, the temperature measurement error is 9.51 °C. After temperature compensation, thermal crosstalk is effectively eliminated and the pressure measurement accuracy is 0.86% F.S.