Phosphors for radiation measurements have attracted attention for various application fields such as medical devices, resource exploration, security, age determination, radiation monitoring, spectroscopies at accelerator, and non-destructive inspection. The phosphors can be categorized into two types. As shown in Figure, A scintillator can emit low energy photons immediately when excited by ionizing radiation. On the other hand, the phosphors for dosimeters can store the energy of the ionizing radiation, and emit low energy photons after the external stimulation such as heat and light. Up to now, single crystalline phosphors, glass phosphors and ceramic phosphors have been development for the applications. The requirements of the phosphors for the applications include a high light yield, high radiation resistance and fast decay time. There is no phosphor which meets all the requirements of all the applications; therefore, a suitable phosphor for the applications should be selected from the present phosphors. Up to now, single crystalline phosphors are often used due to their high light yield. In recent years, transparent ceramic phosphors have been paid attention due to the advantages such as high transparency and high uniformity. In general, ceramics are opaque, but many transparent ceramics have emerged thanks to the development of synthesis technology. In this program, I will fabricate many kinds of transparent ceramic phosphors with a luminescent center, and evaluate their radiation response properties. 

 

Figure Radiation measurement using phosphors