Irradiance-redistribution lens and its applications to LED downlights
US7618162B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2005 |
| Grant date | Nov 17, 2009 |
| Priority date | — |
| Expiry date | Nov 9, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S362/80
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An illumination-redistribution lens comprising a thick aspheric lens collecting a high proportion of the luminous output of a compact LED with a quasi-hemispheric pattern. After receiving the highly nonuniform illuminance from the nearby LED, the lower surface refractively deflects these rays into a less diverging angular pattern that results in uniform illuminance on the upper surface of the lens, which itself is shaped so its distribution of slope angles refractively deflects the uniform illuminance distribution into an exiting beam that will produce uniform illuminance on a distant target, such as a table below a ceiling-mounted unit. When square-cut sections of such lenses are laterally arrayed to form a downlight, a uniform rectangular spot will be produced on the target.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.