Fourier Transform And Grating-Based Spectroscopy With A Mid-Infrared Supercontinuum Source For Trace Gas Detection In Fruit Quality Monitoring

We present a multi-species trace gas sensor based on a fast, compact home-built Fourier transform spectrometer (FTS) combined with a broadband mid-infrared supercontinuum (SC) source. The spectrometer covers the spectral bandwidth of the SC source (2 - 4 mu m) and provides a best spectral resolution of 1 GHz in 6 seconds. It has a detection sensitivity of a few hundred of ppbv Hz(-1/2) for different gas species. We study the performance of the developed spectrometer in terms of precision, linearity, long-term stability, and multi-species detection. We use the spectrometer for measuring fruit-produced volatiles under different atmospheric conditions and compare the performance with a previously developed scanning grating-based spectrometer. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement