Open AccessContinuous-wave cavity ringdown spectroscopy based on the control of cavity reflection
Author(s) -
Zhixin Li,
Weiguang Ma,
Xiaofang Fu,
Wei Tan,
Zhao Gang,
Lei Dong,
Lei Zhang,
Wen Yin,
Suotang Jia
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.017961
Subject(s) - optics , fabry–pérot interferometer , reflection (computer programming) , spectrometer , laser , absorption (acoustics) , cavity ring down spectroscopy , noise (video) , transmission (telecommunications) , spectroscopy , materials science , absorption spectroscopy , signal (programming language) , optical cavity , physics , telecommunications , quantum mechanics , artificial intelligence , computer science , image (mathematics) , programming language
A new type of continuous-wave cavity ringdown spectrometer based on the control of cavity reflection for trace gas detection was designed and evaluated. The technique separated the acquisitions of the ringdown event and the trigger signal to optical switch by detecting the cavity reflection and transmission, respectively. A detailed description of the time sequence of the measurement process was presented. In order to avoid the wrong extraction of ringdown time encountered accidentally in fitting procedure, the laser frequency and cavity length were scanned synchronously. Based on the statistical analysis of measured ringdown times, the frequency normalized minimum detectable absorption in the reflection control mode was 1.7 × 10(-9)cm(-1)Hz(-1/2), which was 5.4 times smaller than that in the transmission control mode. However the signal-to-noise ratio of the absorption spectrum was only 3 times improved since the etalon effect existed. Finally, the peak absorption coefficients of the C(2)H(2) transition near 1530.9nm under different pressures showed a good agreement with the theoretical values.