KTA-OPO dial lidar for hydrocarbon monitoring

We present a Differential Absorption Lidar (DIAL) system employing a type II non-critically phase-matched KTA optical parametric oscillator (OPO) pumped by a Nd:YAG 1064 nm laser. The KTA crystal allows tunable laser radiation in the 3.3–3.5 μm range, targeting the absorption band of hydrocarbons like methane. Lidar measurements in an urban troposphere revealed methane concentrations of approximately 2.085 ppm along a 780 m surface path with a spatial resolution of 100 m. The error in methane concentration recovery ranged from 8% to 13% relative to the averaged value.