Light emitting device, surface light source, liquid crystal display device, and method for manufacturing light emitting device

摘要

A light emitting device includes: a substrate having a main surface; a phosphor layer provided on the main surface and containing an LED element that emits primary light and a fluorescent particle that absorbs a part of the primary light and emits secondary light; and a transparent resin layer having a refractive index n and covering the phosphor layer. The transparent resin layer has an outer circumferential surface that forms a boundary between the transparent resin layer and the atmosphere. When a minimum circumference that includes the overall phosphor layer and is concentric with the outer circumferential surface has a radius r in a cut surface where at least a part of the outer circumferential surface takes a shape of an arc having a radius R, a relationship of R>r·n is satisfied. With such configuration, the light extraction efficiency is enhanced.

主权项

1. A light emitting device, comprising:
a substrate having a main surface; an inner portion provided on said main surface and containing a semiconductor light emitting element that emits primary light and a fluorescent particle that absorbs a part of the primary light and emits secondary light; an outer portion having a refractive index n and covering said inner portion, wherein said outer portion has an outer circumferential surface exposed to the atmosphere, when a minimum spherical circumference that includes overall said inner portion and is concentric with said outer circumferential spherical surface has a radius r in a cut surface where at least a part of said outer circumferential spherical surface takes a shape of an arc having a radius R, a relationship of R>r·n is satisfied; wherein said outer portion is formed of a single transparent layer; said inner portion is a phosphor layer containing said fluorescent particle, and said phosphor layer is provided to be in direct contact with said semiconductor light emitting element and directly cover said semiconductor light emitting element; and wherein said fluorescent particle is provided only in said inner portion, of said inner portion and said outer portion.