LED device compensation method
US7847764B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 15, 2007 |
| Grant date | Dec 7, 2010 |
| Priority date | — |
| Expiry date | Aug 9, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for controlling and compensating aging in an LED device includes measuring a performance change in light output of the LED device. The LED device is controlled with a first compensation algorithm derived from the measured performance change, during a first period, to effect a luminance change over time in the light output of the LED device. Subsequently, a second compensation algorithm, derived from the measured performance change, and different from the first compensation algorithm, during a second period, effects a second luminance change over time in the LED device's light output. The second luminance change over time in the second period is different from the first luminance change over time in the first period. Furthermore, the first and second periods together are less than the lifetime of the LED device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.