Title :
A PPLN-based difference-frequency laser system for cavity leak-out spectroscopy in the 3-/spl mu/m region
Author :
Stry, S. ; Weber, Piotr ; Kleine, D. ; Murtz, M. ; Hering, Pavel ; Meyn, J.-P.
Author_Institution :
Inst. fur Lasermedizin, Dusseldorf Univ., Germany
Abstract :
Summary form only given. In the last years, laser-based spectroscopic techniques for trace gas detection on the ppb level have received increasing attention. Cavity leak-out spectroscopy (CALOS) is a fast, accurate and universal method for online measurement of absolute trace gas concentrations,e.g., the concentration of small hydrocarbons in ambient air samples. The sample gas is filled into an optical cavity formed by a pair of high-reflectivity mirrors. This results in a virtual absorption length of several kilometers depending on the mirror reflectivity, leading to detection limits on the ppb level. In this work we developed a difference frequency laser system, which is tunable from 2797 cm/sup -1/ to 3196 cm/sup -1/ with a fast, modehop free tuning range.
Keywords :
dielectric polarisation; gas sensors; infrared spectroscopy; laser cavity resonators; laser mirrors; lithium compounds; optical frequency conversion; spectrochemical analysis; 3 mum; LiNbO/sub 3/; PPLN-based difference-frequency laser system; absolute trace gas concentrations; cavity leak-out spectroscopy; detection limits; difference frequency laser system; high-reflectivity mirrors; laser-based spectroscopic techniques; modehop free tuning range; optical cavity; trace gas detection; virtual absorption length; Absorption; Frequency; Gas lasers; Hydrocarbons; Laser modes; Laser tuning; Mirrors; Reflectivity; Spectroscopy; Tunable circuits and devices;
Conference_Titel :
Lasers and Electro-Optics, 2000. (CLEO 2000). Conference on
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
1-55752-634-6
DOI :
10.1109/CLEO.2000.907377
