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NASA NTRS · 20040088810

Development of an automated diode-laser-based multicomponent gas sensor

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

The implementation and application of a portable fiber-coupled trace-gas sensor for the detection of several trace gases, including CO2, CH4, and H2CO, are reported. This particular sensor is based on a cw fiber-amplified near-infrared (distributed Bragg reflector) diode laser and an external cavity diode laser that are frequency converted in a periodically poled lithium niobate crystal to the mid-IR spectroscopic fingerprint region (3.3-4.4 micrometers). A continuous absorption spectrum of CH4 and H2CO from 3.37 to 3.10 micrometers with a spectral resolution of 40 MHz (approximately 0.0013 cm-1) demonstrated the spectral performance that can be achieved by means of automated wavelength tuning and phase matching with stepper motor control. Autonomous long-term detection of ambient CO2 and CH4 over a 3- and 7-day period was also demonstrated.

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NASA Discipline Environmental HealthNon-NASA CenterEnvironmental Monitoring/instrumentationGases/analysisSpectrophotometry, Infrared/instrumentationLasersCarbon Dioxide/analysisAutomationEquipment DesignEvaluation StudiesFiber OpticsSupport, U.S. Gov't, Non-P.H.SSupport, Non-U.S. Gov'tMethane/analysisFormaldehyde/analysis

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Richter, D., Lancaster, D. G., Tittel, F. K.. 2000-08-20. Development of an automated diode-laser-based multicomponent gas sensor. https://ntrs.nasa.gov/citations/20040088810

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