Description of a portable devices developed at SCK•CEN for OSL and TL dosimetry

The Expert Group of Radiation Dosimetry and Calibration of the Belgian Nuclear Research Centre (SCK•CEN) uses thermoluminescence (TL) dosimetry for more than thirty years for routine measurements and for R&D purposes. In 2002, an experimental device based on the optically stimulated luminescence (OSL) was developed for research. It works with AL2O3:C detectors (TLD-500 & Luxel_) stimulated with a green line generated by a 150 mW Arþ laser. Since 2008, modular OSL devices have been developed using light emitting diodes (LED) and working with reflection or transmission mode. This paper describes these modules. The characteristics of the different systems are compared on experimental results: detections limits, linearity, sensitivity. The modular device presents advantages in terms of measurement possibilities with respect to the laser device: a small number of modules allows the use of different detection materials (AL2O3:C, BeO, quartz, electronic components) and different measurement methods (TL, CW-OSL and pulsed OSL). The modules are controlled by a personal computer and a microcontroller array. The whole set is able to measure a wide range of doses by changing the number of LEDs and is able to work in situ. The future trends are commented as well as some applications.