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NASA NTRS · 20040088966

Portable fiber-coupled diode-laser-based sensor for multiple trace gas detection

Lancaster, D. G.·Richter, D.·Tittel, F. K.
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Abstract

Tunable narrowband mid-infrared radiation from 3.25 to 4.4 micrometers is generated by a compact fiber-coupled, difference-frequency-based spectroscopic source. A 20-mW external cavity diode laser (with a tuning range from 814 to 870 nm) and a 50-mW distributed-Bragg-reflector diode-laser-seeded ytterbium-doped fiber amplifier operating at 1083 nm are difference-frequency mixed in a multi-grating, temperature-controlled periodically poled LiNbO3 crystal. A conversion efficiency of 0.44 mW/(W2cm) (corresponding to a power of approximately equal to 3 microW at 3.3 micrometers) represents the highest conversion efficiency reported for a portable device. Performance characteristics of such a sensor and its application to spectroscopic detection of CO2, N2O, H2CO, HCl, NO2, and CH4 will be reported in this work.

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Non-NASA CenterNASA Discipline Environmental HealthLasersGases/analysisFiber OpticsNitric OxideHydrochloric AcidCarbon DioxideNitrous OxideEnvironmental Monitoring/instrumentationSupport, Non-U.S. Gov'tMethaneSupport, U.S. Gov't, Non-P.H.S

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Lancaster, D. G., Richter, D., Tittel, F. K.. 1999-11-01. Portable fiber-coupled diode-laser-based sensor for multiple trace gas detection. https://ntrs.nasa.gov/citations/20040088966

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