Optically stimulated luminescence techniques in retrospective dosimetry

Optically stimulated luminescence signals from natural quartz and feldspar are now used routinely in dating geological and archaeological materials. More recently they have also been employed in accident dosimetry, i.e. the retrospective assessment of doses received as a result of a nuclear accident. Since 1990 the exploration of this wide variety of applications has driven an intensive investigation and development programme at Risø, in measurement facilities and techniques. This paper reviews some of the outcomes of this programme, including (i) optimisation of stimulation and emission windows, and detection sensitivity, (ii) experience with various stimulation light sources, including filtered incandescent lamps (420–550 nm) and high intensity light emitting diodes (470 nm) and laser diodes (830–850 nm). We also discuss recently developed high-precision single-aliquot measurement protocols. These offer exciting possibilities in dating and accident dosimetry, and are already leading to new demands on measurement techniques and facilities.