Development of an automated multispecies gas sensor using diode laser pumped difference-frequency generation

Summary form only given. Selective and sensitive mid-IR multi-species gas detection is an attractive tool for many real world applications. Narrow-linewidth mid-IR absorption gas sensors based on difference-frequency mixed near-IR solid-state and diode lasers have been shown to be an effective tool for molecular species detection. In real-world applications such gas sensors can be exposed to considerable temperature fluctuations and vibrations. Depending on the application, such sensors may have to cope with large dynamic changes of the gas concentration and with other potentially interfering gases. We report an automated, compact sized, portable gas sensor that uses widely tunable mid-IR difference-frequency laser generated light applied to multispecies gas detection using direct extractive absorption spectroscopy.