Tunable fiber laser based photoacoustic spectrometer for multi-gas analysis

Abstract A tunable fiber laser based multi-gas photoacoustic spectrometer has been developed. The spectrometer consists of a near infrared tunable fiber laser combining with a fiber amplifier, a first order longitudinal resonant photoacoustic cell and wavelength modulation mechanism. Simultaneous and continuous measurement of trace water vapor, acetylene, carbon dioxide, and carbon monoxide (H 2 O, C 2 H 2 , CO and CO 2 ) in gas mixtures are achieved. The gas detection limits (signal-to-noise ratio = 1) of 70 ppm at 1524.57 nm for H 2 O, 2 ppb at 1529.18 nm for C 2 H 2 , 4 ppm at 1565.35 nm for CO and 4 ppm at 1572.66 nm for CO 2 were demonstrated with the spectrometer.