TOBI: A two-laser beam infrared system for time-resolved plasma diagnostics of infrared active compounds

A compact and transportable two laser beam infrared (TOBI) system based on infrared absorption spectroscopy has been developed for time-resolved plasma diagnostics. The TOBI system contains two independent tunable diode lasers which can be directed through a plasma or into a multipass cell for exhaust gas detection. Rapid scan software with real-time line shape fitting provides a time resolution up to 10 μs to study chemical kinetic processes of infrared active compounds in plasmas. The capabilities of the TOBI system have been demonstrated in plasmas of pulsed H2–N2 surface wave and in pulsed air–CH4 dc discharges.