US Patent 7294865 Light emitting device and the use thereof

A light emitting device includes a die and a photostimulable luminescent substance. The die has a first semiconductor light-emitting layer emitting a first color light having a first wavelength range, and a second semiconductor light-emitting layer emitting a second color light having a second wavelength range different from the first wavelength range. The photostimulable luminescent substance is excitable by at least one of the first and second color lights to emit a third color light having a third wavelength range. The third color light is mixed with the first and second color lights to emit a light blend having a wavelength range covering the first, second, and third wavelength ranges.