Mid-Infrared, Optical, Cavity-Based Spectrometer for Multispecies Airborne and Ground-Based Atmospheric Monitoring

73193S03-I Recent advances in both mid-infrared laser sources and ultrasensitive optical detection technologies offer the opportunity to study trace atmospheric species such as formaldehyde with unprecedented detail and accuracy. The availability of such instrumentation, suitable for both airborne and ground-based monitoring applications, would have a wide ranging impact on our understanding of atmospheric chemistry and dynamics. This project will combine a novel tunable high-power, single-frequency, mid-infrared laser source with an ultrasensitive, optical, cavity-based absorption method known as off-axis integrated cavity output spectroscopy. The combination will allow many important atmospheric constituents (including formaldehyde, CO, ethylene, acetylene, and N2O) to be monitored with unprecedented sensitivity (less than 25 pptv mixing ratio) in real time (less than 30 s). In Phase I, a high-power, single-frequency, infrared laser source, operating in the 2.7 ¿m spectral region, will be constructed and fully characterized. This source will be used in conjunction with off-axis integrated cavity output spectroscopy, which will allow the sensitivity level of this approach to be achieved. Commercial Applications and Other Benefits as described by awardee: The instrument should have a wide ranging impact on our understanding of atmospheric chemistry and dynamics. Commercial applications include trace gas monitoring, pollution monitoring, and industrial process monitoring.