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PubMed · 11543547

Difference-frequency-based tunable absorption spectrometer for detection of atmospheric formaldehyde.

D G Lancaster·A Fried·B Wert·B Henry·F K Tittel
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Abstract

High-sensitivity detection of formaldehyde (CH2O) at 3.5315 micrometers (2831.64 cm-1) is reported with a diode-laser-pumped, fiber-coupled, periodically poled LiNbO3 spectroscopic source. This source replaced the Pb-salt diode laser Dewar assembly of an existing tunable diode-laser absorption spectrometer designed for ultrasensitive detection of CH2O. Spectra are recorded with 2f-modulation spectroscopy and zero-air rapid background subtraction. Initial measurements reported here, determined from multiple measurements of a flowing 7.7 parts per billion by volume (ppbv, parts in 10(9)) CH2O in air mixture, indicate replicate precisions as low as 0.24 ppbv.

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AtmosphereEnvironmental MonitoringEquipment DesignEvaluation Studies as TopicFormaldehydeLasersLeadSpectrophotometry, InfraredNASA Discipline Environmental HealthNon-NASA CenterJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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D G Lancaster, A Fried, B Wert, B Henry, F K Tittel. 2000-08-20. Difference-frequency-based tunable absorption spectrometer for detection of atmospheric formaldehyde.. https://doi.org/10.1364/ao.39.004436

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