More than three centuries later a lot of fundamental questions connected with the TL mechanism has not been satisfactory answered. The TL phenomenon of solids and natural radioactivity enable dating.
Traps can keep for a long time excess carriers excited by radiation.
During the heating the excess carriers are released. Those which recombine with luminescent centres release their energy as TL emission. Fundamental experiment consists in recording this light versus temperature and its result is called the glow curve. The more radioactive energy means the more carriers captured by traps. All problems mentioned above as well as the search for new materials for TL dating implies the necessity of fundamental investigations of the TL mechanism in minerals.