Design of CO, CO2 and CH4 gas sensors based on correlation spectroscopy using a Fabry–Perot interferometer

In this paper we present an analytical methodology to evaluate the response of a gas sensor based on correlation spectroscopy using a Fabry–Perot interferometer (FPI). Here we consider a FPI which is illuminated with a converging beam from a black-body source. It is shown that the optimal FPI cavity length and reflectivity can be easily determined. We designed and tested three different gas sensors (CO, CO2, and CH4) using this methodology. Our numerical results are supported by experimental measurements.