Rapid-response Atmospheric Oxygen Monitor based on Fluorescence Quenching

Abstract

THE energy acquired by matter when it absorbs electromagnetic radiation is normally converted to heat, but in some cases much of the energy may be re-emitted as fluorescence or phosphorescence. Fluorescence is often quenched (that is, its intensity is reduced) in the presence of oxygen. The degree of quenching depends on the probability of an encounter between a molecule of oxygen and a fluorescent molecule in its excited state, and the energy that would otherwise be emitted as fluorescence is transferred to the oxygen. This effect has been used as the basis of a portable instrument to measure the atmospheric oxygen tension (British Patent Application No. 46674/66). Various prototype devices have been constructed and tested.