Efficient luminaire with directional side-light extraction
US7163326B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 2005 |
| Grant date | Jan 16, 2007 |
| Priority date | — |
| Expiry date | May 21, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0061
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A luminaire with directional side-light extraction comprises a light pipe with a light-carrying core. The light pipe has light-extraction structure along a first longitudinal side of the luminaire, which is confined to a radial swath of the luminaire, along the longitudinal axis of the luminaire, of substantially less than 180°. For efficiency, the second end has light-saving structure for directing saved light from the second end towards the first end, at redirection angles other than an excluded range of redirection angles, so long as the photon content of light at so-called alpha redirection angles is at least 10 percent of the photon content of light at so-called beta redirection angles, where the excluded range of redirection angles is defined by:|βr|<=20° and |αr|<|βr|/10,where βr is the beta redirection angle and αr is the alpha redirection angle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.