The conversion of high energy radiation to visible light by luminescent ceramics

A study is presented of the properties of luminescent ceramics which are roughly based on rare-earth doped oxides, oxysulfides, garnets, and silicates. Exemplary luminescent ceramic specimens are prepared on the basis of (Y,Gd)/sub 2/O/sub 3/:Eu, Gd/sub 2/O/sub 2/S:Pr,Ce, Gd/sub 3/Ga/sub 5/O/sub 12/:Cr,Ce, and Y/sub 2/SiO/sub 5/:Pr. The structural and luminescence properties are determined by microscopic surface analysis, scintillation spectroscopy, and optical and time-resolved spectroscopy. Micrographs of polished and chemically etched ceramic cross sections are obtained by optical and scanning electron microscopy. Emission spectra are measured under X-ray excitation (tungsten tube, 50 kV, 40 mA) by a 1/8 monochromator (500 nm blaze) and a S11-photomultiplier. Decay curves are determined.<>