The OXYvisor is a process oxygen analyzer, best utilized to measure oxygen concentration in continuous, online, process monitoring and control applications. It is commonly referred to, as a O2 analyser, oxygen meter, dissolved oxygen meter or DO meter.

The device utilizes an optical quench luminescent technique to measure oxygen concentration by volume (ppmv, molar basis) in gas phase or dissolved oxygen measurement (ppbv, ppmv) in liquid and aqueous phase applications.