Patent ID: 8492778

Claim:
A light emitting diode (LED) device, comprising: a substrate; a first LED chip and a second LED chip arranged on the substrate, the first LED chip being ultraviolet (UV) LED for generating UV light; and a phosphor layer arranged over the first and second LED chips, the phosphor layer comprising a plurality of phosphor units, each phosphor unit comprising a phosphor particle and a silver halide layer encapsulating the phosphor particle; wherein when the first LED chip is turned off and the second LED chip is turned on, a part of light emitted from the second LED chip travelling through the silver halide layer and striking the phosphor particles to generate a first light, which is combined with a residual part of the light emitted from the second LED chip to generated a first resultant light with a first color temperature; and wherein when the first LED chip and the second LED chip are both turned on, the silver halide layer being reduced by the UV light generated from the first LED chip to produce silver particles around the phosphor particles, a part of the light emitted from the second LED chip striking the phosphor particles to generate a second light, which is combined with a residual part of the light emitting from the second LED chip to generate a second resultant light with a second color temperature different from the first color temperature, the silver particles blocking the light emitted from the second LED chip from striking the phosphor particles.