Thermoluminescence of glass display from mobile phones for retrospective and accident dosimetry

This paper deals with the thermoluminescence (TL) study of glass displays from mobile phones with the aim to use them as emergency dosimeters after an accident involving ionizing radiation. Dosimetric properties are analysed in order to examine and to critically evaluate the usability. Tests are carried out regarding the characterization of the radiation induced TL signal and the zero dose signal (intrinsic background) on a variety of display samples. Investigations on the thermal and optical stability of TL signals are carried out. The detection limit is mainly determined by the variability of the zero dose signal and lies in the range of 300-400 mGy. A linear relationship between the measured TL signal and the applied dose is observed for doses between 10 mGy and 20 Gy. A measurement protocol for the detection of absorbed radiation dose is developed, considering the experimental dosimetric properties. A reconstruction of the absorbed dose is possible using glass samples from mobile phones, if the signal loss due to storage and optical bleaching of the TL signal is adequately corrected for. This was confirmed by realistic tests.