Lexsyg luminescence measurement devices: Status and outlook

Abstract

The 2012 introduction of a new concept for an automated luminescence reader where detectors and detection windows can be automatically changed – the lexsygresearch - increased the versatility of luminescence measurements, especially in solid-state dosimetry. This was followed in 2014 by a miniaturized version, lexsygsmart, for more routine luminescence measurement, being equipped only with a single measurement position for a single detector plus an irradiation source. This review provides an update on the current technical specifications for both devices to measure fluorescence and phosphorescence during and after stimulation as radioluminescence, thermoluminescence, and photoluminescence. Key features of the lexsygresearch are the absence of light cross-talk to other sample aliquots and minimized radiation cross-talk while providing true non-stop operation with no breaks required for sample changes. The modular design facilitates the implementation of measurement/detection modules on a four-position detector changer and the five sample treatment positions, thus making upgrades easy. Up to three ionizing radiation sources, some with highly homogeneous fields, including an X-ray generator can be used. Luminescence stimulation can be performed either by irradiation sources, thermally or optically with up to three different wavelengths, while detection windows can be limited by combining two automatic six-position filter wheels. The lexsygresearch can be used as a spectrometer or equipped with Peltier cooling of the sample in addition to the standard heating up to 710 °C. Spatially resolved luminescence, as well as the individual laser stimulation of single mineral grains, is possible, while time-resolved/pulsing luminescence measurements not only provide means for fundamental research but also allow IRPL measurement of feldspar. For the analysis of SAR OSL data, the software LexEva provides a user interface to the R ‘Luminescence’ package, and thus, the results of dose determinations rely on a community-driven open-source project.