Light emitting device, surface light source, liquid crystal display device, and method for manufacturing light emitting device
US9634203B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 2009 |
| Grant date | Apr 25, 2017 |
| Priority date | — |
| Expiry date | Sep 17, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/8514
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.