Lightguide comprising a low refractive index region
US8033706B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 2010 |
| Grant date | Oct 11, 2011 |
| Priority date | — |
| Expiry date | May 7, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0046
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In one embodiment of this invention, a lightguide comprises a low refractive index region disposed between light extracting region and a non-scattering region. In further embodiment of this invention, volumetric scattering lightguide comprises a low refractive index region disposed between a volumetric scattering region and a non-scattering region. In some embodiments, a light emitting device comprising a volumetric scattering lightguide can angularly filter light input into the edge of a volumetric scattering lightguide by controlling the refractive index of the low refractive index region relative to the refractive index of the non-scattering region to prevent direct illumination of the volumetric scattering region, provide a luminance uniformity greater than 70%, or improve the angular luminous intensity of the light emitting device. The volumetric scattering lightguide may be curved, tapered, and a light emitting device comprising the same may further comprise at least one light source and a light redirecting element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.