Patent ID: 9518215
Filing Date: 2016-12-13
CPC Classification: C09K,H01L,H05B

Claim Text:
1. A light-emitting device comprising: a photoluminescent layer that has a first surface perpendicular to a thickness direction thereof and emits light containing first light, an area of the first surface being larger than a sectional area of the photoluminescent layer perpendicular to the first surface; a light-transmissive layer located on the photoluminescent layer; and one or more reflectors that are located directly on at least one of the photoluminescent layer and the light-transmissive layer, and at least partially surround the submicron structure, wherein at least one of the photoluminescent layer and the light-transmissive layer has a submicron structure comprising at least projections or recesses arranged perpendicular to a thickness direction of the photoluminescent layer, at least one of the photoluminescent layer and the light-transmissive layer has a light emitting surface perpendicular to the thickness direction of the photoluminescent layer, the first light being emitted from the light emitting surface, the submicron structure satisfies the following relationship: where D int is a center-to-center distance between adjacent projections or recesses, λ a is the wavelength of the first light in air, and n wav-a is the refractive index of the photoluminescent layer for the first light, and a thickness of the photoluminescent layer, the refractive index of the photoluminescent layer and the center-to-center distance are set to limit a directional angle of the first light emitted from the light emitting surface.