Detection of CO based on optical feedback cavity enhanced absorption spectroscopy

Carbon monoxide (CO) is an important object for atmospheric quality and medical diagnosis, and its trace concentration detection technology has been of great attention. For this purpose, various new detection methods have emerged, such as cavity ring down absorption spectroscopy and cavity enhanced absorption spectroscopy. In this paper, the demand for CO ppm-level trace concentration detection is taken as the traction, and an optical feedback cavity enhanced absorption spectroscopy system with an equivalent noise absorption sensitivity of 7.4×10-10cm-1Hz-1/2 is established to carry out the experiment of near-infrared detection of CO gas concentration. Based on the measurement data of the OF-CEAS system, the minimum measurable CO concentration of the system was inferred to be 1.98 ppm. This system can be developed as a portable respiratory gas diagnostic device and an atmospheric trace gas detection device such as NH3 and CO.