Solid state scintillator and treatment therefor

A polycrystalline ceramic scintillator (14) is disclosed for radiographic applications which has received a controlled oxidation anneal to reduce radiation damage otherwise occuring when said scintillator is exposed to X radiation during conversion of said X radiation to the display image. The particular ceramic material treated in said manner comprises a densely sintered rare earth doped gadolinia containing metal oxide having a cubic crystal structure which has been annealed after sintering in a controlled oxygen containing atmosphere. A preferred ceramic composition comprises from about 5 mole percent up to about 50 mole percent Gd2O3, between about 0.5 mole percent and 12 mole percent of a rare earth activator oxide selected from the group consisting of Eu2O3 and Nd2O3, and between about .0001 and 0.5 mole percent of at least one afterglow reducer selected from the group consisting of Pr2O3 and Tb2O3, and the remainder of said composition being Y2O3. A treatment to produce said improved x-ray conversion medium is also disclosed along with radiographic imaging systems and methods employing said improved x-ray image conversion medium.