Patent ID: 8268192

Claim:
A blue phosphor, comprising: BaMgAl 10 O 17 :Eu (BAM) phosphor particles having a surface component and an internal component, wherein an aluminum/barium (Al/Ba) molar ratio of the surface component of the phosphor particles is 1.1 to about 1.4 times the Al/Ba molar ratio of the internal component of the phosphor particles, and the Al/Ba molar ratios are continuously variable between the internal component and the surface component, wherein: the Al/Ba molar ratio of the surface component is an average Al/Ba molar ratio of a section where a variation rate of an Al/Ba molar ratio according to a depth of the phosphor particle is about −0.01 to about 0.01, as determined from a surface toward a center of the phosphor particle, and the Al/Ba molar ratio of the internal component is an average Al/Ba molar ratio of a section where the variation rate of the Al/Ba molar ratio according to the depth of the phosphor particle is about −0.01 to about 0.01, as determined from the center toward the surface of the phosphor particle.