A fiber optic scintillator includes (18), for example, a plurality of relatively low-density glass scintillating elements (20) for converting radiation into light and a plurality of relatively high-density glass radiation absorbing elements (40) interspersed among the plurality of scintillating elements (20). The high-density glass radiation absorbing elements (40) increase the x-ray stopping power of the scintillator and also produce electron showers which interact desirably in adjacent scintillating elements (20) to increase the luminance of the scintillator (18). The high-density glass radiation absorbing elements also absorb x-ray cross-talk from absorption of radiation in the scintillating elements (20) and desirably include optical absorbers for absorbing optical cross-talk, both of which improves the resolution of the scintillator (18). The plurality of scintillating elements (20) and high-density glass radiation absorbing elements (40) typically are fibers, and the high-density glass radiation absorbing elements (140) may define cladding around the scintillating low-density glass fibers. <IMAGE>
High resolution and high luminance scintillator and radiation imager employing the same