Influence of Temperature on All-Silica Fabry-Pérot Pressure Sensor

An all-silica Fabry-Pérot interferometer (FPI) is demonstrated for high-temperature pressure monitoring. The pressure sensor is fabricated with single mode fiber and silica capillary by CO ₂ laser. Owing to slight mismatch of thermal expansion coefficient in all-silica structure, it can work stably under 600°C atmosphere. The influence of the temperature on the pressure sensor was investigated within a temperature range from 25°C to 700°C and a pressure range from standard atmosphere pressure to 4 MPa. The experimental results show that the wavelength shift versus the pressure at each temperature is linear, which indicates the proposed FPI pressure sensor has potential applications in industrial reactors, oil and gas wells, and so on.