A method for producing CsX:Eu stimulable phosphors and screens or panels provided with said phosphors as
powder phosphors or vapor deposited needle-shaped phosphors suitable for use in image forming methods for recording and reproducing images of objects made by
high energy radiation, wherein said CsX:Eu stimulable phosphors are essentially free from
oxygen in their
crystal structure, and wherein X represents a
halide selected from the group consisting of Br, Cl and combinations thereof, and wherein the method further makes use of starting compounds (precursors) or combinations of precursors for the synthesis of said CsX:Eu stimulable phosphors, said precursors (starting compounds) having as a composition CsxEuyX′x+αy, wherein the ratio of x to y exceeds a value of 0.25, wherein α>2 and wherein X′ is a
halide selected from the group consisting of Cl, Br and I and combinations thereof; heating said mixture at a temperature above 450° C.; cooling said mixture, and optionally annealing and recovering said CsX:Eu
phosphor.