An optical sensing system for the concentration of methane based on fiber Bragg gratings

Based on a special catalyst and fiber Bragg gratings （FBGs）, an optical sensing system is proposed to measure the concentration of methane. The temperature of the catalyst rises rapidly as the concentration of methane increases, and hence it can be detected by an FBG-type sensor through monitoring the wavelength shift of the reflection spectrum. The experimental results show the good performances of our system, such as the high resolution and temperature stability.