Technology Makes Solid State Multi-Gas Emission Monitoring Possible

Abstract

A recent breakthrough in the growth of excellent quality single crystal thallium arsenic selenide (TAS) on a production basis has made it possible to buLld an electronically controlled acousto optic tunable filter (AOTF) capable of operating in the infrared. Such a filter with integral ultrasonic transducer can be used in place of mechanical filter wheels, spinning gas cells, moving mirrors, diffraction gratings and mechanical light choppers. The TAS AOTF produces an electronically controllable narrow panel infrared filter capable of being tuned to any infrared frequency desired. It provides a chopped and tuned IR source that can be directed across the stack on any combustion process to measure the concentrations of CO, CO2, SO2, C2H6, CH4, NO, NO2, H2O, etc. simultaneously.