JPS6439576A - Radiation position detector - Google Patents

Abstract

PURPOSE:To obtain excellent position resolution by converging output light from each scintillator element and directing the output light toward an optical coupling material and a light position detector. CONSTITUTION:A radiation position detector 1 uses a scintillator 3 consisting of a bundle of rod type scintillator elements 2(2a-2e) and the light output surfaces 7(7a-7e) of the respective elements 2 are machined into curved surfaces like convex lenses. Those light output surfaces 7 are coupled with the glass window material 58 of the light position detector 53 by an optical coupling material 4 such as grease. The detector 1 emits many light beams in equal directions when radiation enters the element 2b and is absorbed in the element 2. Those light beams reach the light output surface 7b while being reflected by the flank, etc., of the element 2b. At this time, light from the light output surface 7b is converged through lens effect on the border between the element 2b which is large in refractive index and the coupling material 4 which is small in refractive index. Thus, the spatial spread of output light from each element 2 is reduced, so excellent position resolution is obtained.