An Ultra-Simple Microchannel-Free Fiber-Optic Gas-Pressure Sensor With Ultra-Fast Response

An ultra-simple microchannel-free fiber-optic gas-pressure sensor based on a section of quartz capillary is proposed. The resonance peaks and interference fringes can be both shown in the reflection spectrum and they are both sensitive to the variation of the gas refractive index and temperature. The gas-pressure can be demodulated by using sensing matrix. As the quartz capillary is open completely at its end, the pressure response time is reduced to 0.02s for the pressure variation of 0.1MPa. The proposed sensor can have actual applications in 24-hour gas-pressure monitoring and early warning in harsh environment, because of its ultra-simple and all-silica structure, ultra-fast response, good repeatability, and ultra-low fabrication cost.