Title :
Accurate gas diagnostics for sealed-off CO2 lasers using near-infrared DFB semiconductor lasers
Author :
Lorini, L. ; De Natale, P. ; Lapucci, A.
Author_Institution :
Ist. Nazionale di Ottica, Florence, Italy
fDate :
6/1/1998 12:00:00 AM
Abstract :
The selective spectroscopic detection of CO2 and H2O in the gas mixture of a 400-W sealed-off CO2 slab laser is reported. The detection is based on the acquisition of absorption Voigt profiles of two vibrational overtone transitions of CO 2 and H2O, obtained using two InGaAsP distributed feedback (DFB) semiconductor lasers. This spectroscopic method enables a direct absolute measurement of the temporal evolution for the concentrations inside the laser active volume. Monitoring takes place during laser operation without gas extraction. The experiments carried out on CO2 and H2O abundances confirm the paramount importance of wall desorbance phenomena in all-metal radio frequency (RF) excited lasers
Keywords :
carbon compounds; chemical variables measurement; gas lasers; laser variables measurement; measurement by laser beam; monitoring; spectral line breadth; spectrochemical analysis; vibrational states; 400 W; CO2; CO2 slab laser; H2O; InGaAsP; InGaAsP DFB semiconductor lasers; absorption Voigt profiles; accurate gas diagnostics; all-metal RF excited lasers; concentration; direct absolute measurement; gas mixture; laser active volume; monitoring; near-infrared DFB semiconductor lasers; sealed-off CO2 lasers; selective spectroscopic detection; spectroscopic method; temporal evolution; vibrational overtone transitions; wall desorbance phenomena; Absorption; Distributed feedback devices; Gas detectors; Gas lasers; Laser feedback; Laser transitions; Radio frequency; Semiconductor lasers; Slabs; Spectroscopy;
Journal_Title :
Quantum Electronics, IEEE Journal of
