A light emitting device in which a primary light generator, such as a
light emitting diode (LED) or laser diode, is operable to emit a primary
light that is received by a body of wavelength converting material. A
portion of the primary light is absorbed by the body of wavelength
converting material and is emitted as secondary light. The wavelength
converting material contains phosphor nano-particles and larger phosphor
particles. The phosphor nano-particles prevent transmission of primary
light while the larger phosphor particles provide efficient light
conversion.