Patent ID: 7183560

Claim:
Storage phosphor particle containing at its particle surface and its inner volume as components composing the said phosphor a matrix component (1-x)M I X.xM II X 2 , wherein M(I) is at least one of monovalent Li, Na, K, Rb or Cs, M(II) is a divalent metal element selected from the group consisting of Mg, Ca, Sr, Ba and Ni; and wherein 0 ≦x <0.5; and an activator component Ln, wherein Ln stands for Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Bi, In or Ga, wherein said particle is characterized by an aspect ratio of more than 2.0, said aspect ratio being defined as a ratio of 2 largest sizes of said particles, said sizes being taken in 3 dimensions perpendicular to each other, provided that one of said 2 largest sizes is smaller than 10 μm.