Industrial gas analytics using a compact ultraviolet laser

Abstract

Ultraviolet light in the wavelength range between 200 nm and 240 nm is of great interest for spectroscopic gas analytics. Particularly, for industrial applications, optical gas analyzers based on this spectral range are promising for combustion gas and natural gas analytics but require availability of suitable robust, compact and low-cost light sources. We have demonstrated a gas analyzer using a compact solid-state laser module which emits wavelengths near 219 nm and which offers significant advantages compared with conventional light sources. The key characteristics of the laser module are outlined in the paper and the integration of the laser into a gas analyzer prototype is described. In a simple absorption setup, using the example of hydrogen sulfide as analyte, we demonstrate a detection limit of 0.02 ppm•m (3 σ, 50 s average, 1 Hz sampling rate). The properties of the laser having a small footprint, low supply voltage, and low power consumption are key advantages for the integration into future robust, low-cost, industrial products.