Remote atmospheric measurements of SO2 and CH4 were performed using a differential absorption lidar with a continuously tunable LiNbO3 parametric oscillator and amplifier source in the 1.4–4.0-µm region. A comparison of injected gas concentration in a remotely located sample chamber showed excellent agreement with a SO2 detection sensitivity of 0.9 ppm-km. An ambient level measurement of methane at the 1.66-µm overtone transition gave 3.9 ± 0.7 ppm Performance predictions indicate an order of magnitude gain in sensitivity is possible with recently demonstrated tunable source improvements. The wide tuning range capability allows the measurement of numerous other pollutant molecules in the 1.4–4.0-µm region.
© 1978 Optical Society of America
R. A. Baumgartner and R. L. Byer, "Continuously tunable ir lidar with applications to remote measurements of SO2 and CH4," Appl. Opt. 17, 3555-3561 (1978)