Thermoluminescence instruments are designed to investigate structure of energetic levels in the Photosystem II. Light-induced charge separation in the Photosystem II reaction centers results in accumulation of radical pairs that store the absorbed light energy. Heating induces recombination of these radical pairs and it triggers light emission and formation of characteristic thermoluminescence glow curves.

The Thermoluminescence system has been significantly enhanced by the end of 2018 and now it is offered in two versions that differ in the range of controlled temperature:

• Thermoluminescence System TL 6000/ST
Temperature control in the range of -25 °C to +70 °C.
• Thermoluminescence System TL 6000/ET
Temperature control in the range of -100 °C to +200 °C.