Chemical sensing with pulsed QC-DFB lasers operating at 15.6 μm

Pulsed thermoelectrically cooled QC-DFB lasers operating at 15.6 mum were characterized for spectroscopic gas sensing applications. A new method for wavelength scanning based on repetition rate modulation was developed. A nonwavelength-selective pyroelectric detector was incorporated in the sensor configuration giving the advantage of room-temperature operation and low cost. Absorption lines Of CO2 and H2O were observed in ambient air, providing information about the concentration of these species.