LED illumination system having an intensity monitoring system
US7294816B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2003 |
| Grant date | Nov 13, 2007 |
| Priority date | — |
| Expiry date | Aug 30, 2024 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21Y2115/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light source and method for controlling the same. The light source includes a first component light source that includes N LEDs, a photo-detector, and a collector, where N>1. Each LED has a light emitting chip in a package. The light emitting chip emits light in a forward direction and light in a side direction. The light generated in the forward direction is determined by a drive signal coupled to that LED. A portion of the light in the side direction leaves the package. The collector is positioned such that a portion of the light in the side direction that leaves the package of each of the LEDs is directed onto the photo-detector. The photo-detector generates N intensity signals, each intensity signal having an amplitude related to the intensity of the light emitted in the side direction by a corresponding one of the LEDs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.