X-Ray intensifying screens

Abstract

An X-ray intensifying screen having a high speed and capable of providing good image quality superior in sharpness, granularity and contrast comprising a support having formed thereon a fluorescent layer composed of a complex halide phosphor represented by the composition formula shown below and having further formed on the fluorescent layer another fluorescent layer composed of a calcium tungstate phosphor: (Me.sub.1-f, Mg.sub.f)F.sub.2 .multidot.aMe'X.sub.2 .multidot.bKX'.multidot.cMe"SO.sub.4 :dEu.sup.2+,eTb.sup.3+ wherein Me, Me' and Me" each represents at least one of the alkaline earth metals of the group consisting of barium, strontium and calcium; X and X' each represents at least one of chlorine and bromine; and a, b, c, d, e and f are the numbers defined by one of the following five combinations: 1. 0.80.ltoreq.a.sub.1 .ltoreq.1.50, 0.10.ltoreq.b.sub.1 .ltoreq.1.50, c.sub.1 .dbd.0, 0.001.ltoreq.d.sub.1 .ltoreq.0.20, e.sub.1 .dbd.0 and f.sub.1 .dbd.0; 2. 0.30.ltoreq.a.sub.2 .ltoreq.1.50, 0.10.ltoreq.b.sub.2 .ltoreq.2.00, 0.01.ltoreq.c.sub.2 .ltoreq.1.00, 0.001.ltoreq.d.sub.2 .ltoreq.0.20, e.sub.2 .dbd.0 and f.sub.2 .dbd.0; 3. a.sub.3 .dbd.1, b.sub.3 .dbd.0, c.sub.3 .dbd.0, 0.01.ltoreq.d.sub.3 .ltoreq.0.10, 0<e.sub.3 .ltoreq.0.05 and f.sub.3 .dbd.0; 4. a.sub.4 .dbd.1, b.sub.4 .dbd.0, c.sub.4 .dbd.0, 0.001.ltoreq.d.sub.4 .ltoreq.0.20, e.sub.4 .dbd.0 and 0<f.sub.4 .ltoreq.1; and 5. a.sub.5 .dbd.1, 0<b.sub.5 .ltoreq.1.5, c.sub.5 .dbd.0, 0.001.ltoreq.d.sub.5 .ltoreq.0.20, e.sub.5 .dbd.0 and 0<f.sub.5 .ltoreq.1.

Dependencies are inferred from the claim text.