Functionality and dose determination

The principle of Optically Stimulated Luminescence (OSL) is similar to the principle of Thermally Stimulated Luminescence (TL). Energy in the form of ionizing radiation hits the detector made of BeO and is stored by lifting electrons to higher energy levels. During this process, electrons are trapped in so-called electrical traps until excitation by light occurs again and the electrons fall back to the lower energy base level. This causes the detector to release the stored energy in the form of light. The light output measured with photomultipliers is then a measure of the dose.

Unlike Thermally Stimulated Luminescence, Optically Stimulated Luminescence is not excited with heat but with light.