Photostimulated Thermoluminescence of Lithium Fluoride As an Ultraviolet Radiation Dosimeter

TLD-100 (lithium fluoride) thermoluminescence dosimeters are widely employed for the detection of ionizing radiations. This paper shows that these dosimeters may also serve as practical germicidal ultraviolet radiation dosimeters. To measure u.v. radiation, the TLD-100 dosimeters are first exposed to 500,000 R of gamma radiation and then heated to 300°C at a temperature rate of 3°C/sec and annealed at 300°C for 1 min. Subsequent dosage of u.v. radiation may be determined by observation of photostimulated thermoluminescence of the crystal. The presented data indicate that the thermoluminescence response is linear for exposures up to 6000 μJ/cm2 and independent of exposure rate from 0.1 μW/cm2 to above 50 μW/cm2. Optical absorption and sensitivity as a function of temperature of the dosimeters during u.v. exposure are presented.