Differential laser-induced thermoelastic spectroscopy for dual-gas CO2/CH4 detection

• A novel differential laser-induced thermoelastic spectroscopy (D-LITES) was demonstrated. In D-LITES, one probe and one control laser beam with different modulation phases were combined to generate two quartz tuning fork (QTF) mechanical oscillations, which are pi out of phase. The powers of the two lasers were adjusted to balance out the background noise. The differential signal was acquired by demodulating the QTF piezoelectric signal. The D-LITES sensor had a compact and cost-effective one-path configuration and was able to realize dualgas detection. Carbon dioxide (CO2) and methane (CH4) were chosen as target gases to verify the D-LITES sensor performance. With the D-LITES technique, the background noise was greatly suppressed. The minimum detection limit (MDL) was improved by 9 times from 260 ppm to 29 ppm and 7.13 times from 0.385 ppm to 0.054 ppm for CO2 and CH4 detection, respectively.

Ämnesord

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

Nyckelord

QTF

LITES

Differential detection

Background elimination

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)