OXYTRANS continuously measures the content of oxygen in liquids and gases. This device is designed for breweries and applications that require maximum sensitivity and high accuracy. The state of the art optical measurement technology is based on the effect of luminescence quenching. An indicator layer on a small glass component installed in the measuring head is illuminated with blue-green-light. When the indicator molecules absorb the incident light they are promoted to a higher energy state. After a certain time they convert back to a lower energy state during which a detectable red light is emitted. If O2 is present the energy is transferred from the indicator molecules to the oxygen. The detected signal decreases according to the oxygen content.