Evaluating the effects of increased stimulation power on a beryllium oxide real-time optically stimulated luminescence fibre-coupled dosimeter

We report the development and testing of a fibre-coupled, real-time optically stimulated luminescence (rtOSL) beryllium oxide (BeO) dosimeter with a 3 W fibre-coupled laser diode, upgraded from the previous iteration's 40 mW laser. The high laser power coupled to the 1 mm long, 1 mm diameter BeO ceramic pellet resulted in rtOSL signals with significantly larger signal-to-noise ratios. The rtOSL signals exhibited increased nonlinearity with irradiation time due to the increased bleaching power of the detector. This signal nonlinearity was corrected using depletion and deconvolution correction techniques, producing signals with a mean absolute difference (MAD) from their linear fits of 4.0 % and 2.1 % respectively. The corrected rtOSL signals were observed to be linear with dose rate and stem effect-free. • A real-time OSL BeO dosimeter was upgraded with a 3 W laser diode. • Signal amplitude and noise from the upgraded system was compared with that of the previous 40 mW system. • Two nonlinearity correction methods were compared, with the deconvolution technique outperforming the depletion technique. • Corrected rtOSL signals were observed to be linear with dose rate and stem effect-free.