Patent ID: 7695150

Claim:
A lighting unit comprising: a light source that emits blue light; a light guide plate through which light from the light source propagates so that the light is applied in a planar fashion; a green phosphor layer that converts blue light into green light; a red phosphor layer that converts blue light into red light, the red phosphor layer being separated from the green phosphor layer and arranged closer to the light source than the green phosphor layer; wherein the green phosphor layer includes green phosphor beads dispersed in a base material, the green phosphor beads each containing a plurality of green phosphor particles coated with hydrophobic material; the red phosphor layer includes red phosphor beads dispersed in a base material, the red phosphor beads each containing a plurality of red phosphor particles coated with hydrophobic material; and the maximum value for the average particle size of the green phosphor particles and the red phosphor particles is less than about one-fifth the size of the phosphor beads.