Variable sensitivity online optical fibre radiation dosimeter

The use of Poly Methyl MethAcrylate (PMMA) optical fibres for monitoring a wide range of radiation doses, for a multi-functional dosimeter, is being investigated. The sensitivity of the fibre to ionising radiation is shown to be dependant on wavelength, with the sensitivity increasing with decreasing wavelength. The fibres exhibit high sensitivity, as high as 0.6dBm^-1/kGy, and are capable of monitoring dose ranges between 30Gy and 45kGy. This exceeds the sensing range of all currently commercially available PMMA slab sensors. By carefully selecting the monitoring wavelength, the exact sensitivity and dose range can be achieved, thereby allowing the dosimeter to be suitable for a wide range of applications.