The principal active component of the thermoluminescent dosimeter is a special crystal called phosphors. Phosphors are phosphorescent substances that can be excited by visible light and release stored excitation energy as visible light.
The principal active component of the thermoluminescent dosimeter is a special crystal called phosphors. Phosphors are phosphorescent substances that can be excited by visible light, causing the atoms or molecules in the crystal to enter metastable states. When these states decay, they release stored excitation energy as visible light.
Thermoluminescence is a process in which the excitation energy in a ceramic crystal can be frozen in after it has cooled from firing. By heating the ceramic, the stored excitation energy is slowly released as visible light. The amount of light emitted decreases with age, making it possible to use thermoluminescence to date antiquities.
An example of a thermoluminescent dosimeter is the optically stimulated luminescence (OSL) dosimeter. It contains a phosphor crystal that emits light when exposed to ionizing radiation, and the amount of light emitted is proportional to the radiation dose received.