LED illumination device and calibration method for accurately characterizing the emission LEDs and photodetector(s) included within the LED illumination device
US9392660B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 2014 |
| Grant date | Jul 12, 2016 |
| Priority date | — |
| Expiry date | Aug 28, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B47/195
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An illumination device and method is provided herein for calibrating individual LEDs and photodetector(s) included within the illumination device, so as to obtain a desired luminous flux and a desired chromaticity of the device over time as the LEDs age. Specifically, a calibration method is provided herein for characterizing each emission LED and each photodetector separately. The wavelength and intensity of the illumination produced by each emission LED is accurately characterized over a plurality of different drive currents and ambient temperatures, and at least a subset of the wavelength and intensity measurement values are stored with a storage medium of the illumination device for each emission LED. The responsivity of the photodetector is accurately characterized over emitter wavelength and photodetector junction temperature, and results of said characterization are stored with the storage medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.