Near-infrared broad-band cavity enhanced absorption spectroscopy using a superluminescent light emitting diode.
A fibre coupled near-infrared superluminescent light emitting diode that emits approximately 10 mW of radiation between 1.62 and 1.7 microm is employed in combination with a broad-band cavity enhanced spectrometer consisting of a linear optical cavity with mirrors of reflectivity approximately 99.98% and either a dispersive near-infrared spectrometer or a Fourier transform interferometer. Results are presented on the absorption of 1,3-butadiene, and sensitivities are achieved of 6.1 x 10(-8) cm(-1) using the dispersive spectrometer in combination with phase-sensitive detection, and 1.5 x 10(-8) cm(-1) using the Fourier transform interferometer (expressed as a minimum detectable absorption coefficient) over several minutes of acquisition time.
Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, UKOX1 3QZ.
W
W
Denzer
M L
ML
Hamilton
G
G
Hancock
M
M
Islam
C E
CE
Langley
R
R
Peverall
G A D
GA
Ritchie
D000042:Absorption; D000393:Air Pollutants / Q000737:chemistry; D002070:Butadienes / Q000737:chemistry; D004566:Electrodes; D007221:Industry; D049449:Luminescence; D013055:Spectrophotometry, Infrared / Q000295:instrumentation* / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared
D000393:Air Pollutants; D002070:Butadienes; C031763:1,3-butadiene