Detection of methane by a surface plasmon resonance sensor based on polarization interferometry and angle modulation

A novel methane sensor based on surface plasmon resonance is presented. An isoprene rubber (IPR) film is used as the sensing layer for methane. With the technologies of polarization interferometry and angle modulation, a detecting resolution of 700 ppm is achieved, which is better than previously reported methane sensors based on surface plasmon resonance and has a potential to be improved. The technique could have potential applications in monitoring methane concentrations.