Translator Disclaimer
17 September 2013 Enhancements to INO's broadband SWIR/MWIR spectroscopic lidar
Author Affiliations +
Recent advances in the INO broadband SWIR/MWIR spectroscopic lidar will be presented. The system is designed for the detection of gaseous pollutants via active infrared differential optical absorption spectroscopy (DOAS). Two distinctive features are a sub-nanosecond PPMgO:LN OPG capable of generating broadband (10 to <100 nm FWHM) and tunable (1.5 to 3.8 μm) SWIR/MWIR light, and an in-house gated MCT-APD focal plane array used in the output plane of a grating spectrograph. The operation consists in closely gating the returns from back-scattering off topographic features, and is thus, for now, a path integrated measurement. All wavelengths are emitted and received simultaneously, for low concentration measurements and DOAS fitting methods are then applied. The OPG approach enables the generation of moderate FWHM continua with high spectral energy density and tunable to absorption features of many molecules. Recent measurements demonstrating a minimum sensitivity of 10 ppm-m for methane around 3.3 μm with ∼ 2 mW average power in less than 10 seconds will be described. Results of enhancements to the laser source using small or large bandwidth seeds constructed from telecom off-the-shelf components indicate that the OPG output spectral energy density can have controllable spectral widths and shapes. It also has a slightly more stable spectral shape from pulse to pulse than without the seed (25 % enhancement). Most importantly, the stabilized output spectra will allow more sensitive measurements.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Simon Lambert-Girard, François Babin, Martin Allard, and Michel Piché "Enhancements to INO's broadband SWIR/MWIR spectroscopic lidar", Proc. SPIE 8872, Lidar Remote Sensing for Environmental Monitoring XIV, 88720K (17 September 2013);

Back to Top