Patent ID: 8890102

Claim:
A photoexcitable storage phosphor which comprises at least one rare earth element in the trivalent +3 oxidation state and wherein upon irradiation by X-ray, γ-ray or UV radiation the trivalent +3 oxidation state is reduced to divalent +2 oxidation state, and the photoexcitable storage phosphor comprises submicron size particles, wherein the photoexcitable storage phosphor is represented by a formula (A): MeX 1 X 2 :RE 3+ , wherein Me represents a metal ion, X 1 and X 2 is independently a halogen atom selected from the group consisting of chlorine, fluorine, bromine, and iodine; and RE is a rare earth element, and comprising the at least one rare earth element in a concentration of about 0.01% to about 5% relative to the metal halide concentration.