Developments in luminescence measurement techniques

We report on our continuing investigation and development of new measurement facilities for use in irradiation, optical stimulation and luminescence signal detection; these facilities have potential application to all forms of luminescence-based retrospective dosimetry, and are particularly intended for use with the Risø TL/OSL reader. We have investigated the potential of new more powerful blue (455 nm) and green (530 nm) LEDs, and of gated counting combined with pulsed stimulation light techniques using conventional LEDs. Measurement of time-resolved OSL has resulted in a method of real-time separation of quartz and feldspar signals from mixed samples. We also report on progress in the development, testing and documentation of mini X-ray generators as an alternative to a 90Sr/90Y beta source. A conventional 50 kV/1 mA filament tube and a newer 30 kV/0.1 mA cold cathode tube are considered; both types are very stable and reproducible. Other recent developments include the modification of a Risø reader to measure both thermally and optically stimulated electrons (TSE and OSE) from granular or chip phosphors.