Light emitting device having a specific dimension of phosphor layer
US8598778B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 2013 |
| Grant date | Dec 3, 2013 |
| Priority date | — |
| Expiry date | Jul 9, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/8512
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light emitting device includes a base; a light emitting diode (LED) supported by the base; a layer spaced apart from the LED and including a light emitting material of refraction index n1. An enclosure formed by the layer and the base encloses the LED. A medium inside the enclosure between the LED and the layer has a refraction index n0<n1; and an optic in contact with the layer and having a refraction index n2≧n1. The layer is positioned between the optic and the LED. The optic has, at a surface of contact with the layer, a radius r measured along a ray originating from the LED, and, at an output surface of the optic, another radius R measured along the same ray, such that R≧r·(n1/nm), where nm is a refraction index of a medium adjacent the output surface of the optic.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.