Patent ID: 10012780

Abstract:
A light-emitting device includes a photoluminescent layer and a light-transmissive layer located on the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a submicron structure having at least projections or recesses arranged perpendicular to the thickness direction of the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a light emitting surface. The first light has a wavelength λa in air. A distance Dint between adjacent projections or recesses and a refractive index nwav-a of the photoluminescent layer for the first light satisfy λa/nwav-a<Dint<λa. A thickness of the photoluminescent layer, the refractive index nwav-a, and the distance Dint are set to limit a directional angle of the first light emitted from the light emitting surface.