Apparatus for producing a spectrally-shifted light output from a light emitting device utilizing thin-film luminescent layers

摘要

A lighting device provides a spectrally-shifted light output from a light source. The lighting device includes a semiconductor light emitting device providing a source light and a first thin-film luminescent material layer coating a surface of the semiconductor light emitting device. The first thin-film luminescent material layer includes a luminescent material that emits an emitted light in response to the source light. The first thin-film luminescent material layer has a specific and consistent thickness and specific and consistent density of luminescent particles. The emitted light includes a first luminescent material emitted light when the luminescent material completely absorbs the source light. The emitted light includes a first composite light when the first luminescent material absorbs less than all of the source light. The device may further include a second thin-film luminescent layer coating the first thin-film luminescent layer.