Active and passive infrared spectroscopy for the detection of environmental threats

Block MEMS/Engineering develops mid-infrared spectroscopy systems based on both Fourier transform infrared (FTIR) spectrometers and quantum cascade lasers (QCLs). Our recently developed miniaturized external-cavity QCLs are widely tunable over a spectral range of >250 cm^-1 and tuning can be accomplished at rates of <25 cm^-1 per millisecond. This enables high-speed mid-infrared spectroscopy of gases and surface contaminants for a variety of military and commercial applications. This paper provides an overview of our FTIR and QCL systems and their defense-related applications.