LED lighting device and LCD device using the same
US7932681B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 2009 |
| Grant date | Apr 26, 2011 |
| Priority date | — |
| Expiry date | May 8, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lighting device includes at least two lines connected in parallel, a constant current source for applying a constant current to at least one of the at least two lines, an ON/OFF controller, and a voltage detector for measuring a value of voltage flowing in each line of the at least two lines. Each line of the at least two lines is formed by one or more light-emitting diodes and a switch for turning ON/OFF the current flowing in the light-emitting diodes connected in series, and according to the voltage value of each line of the at least two lines measured by the voltage detector, the ON/OFF controller controls the duty ratio of the one or more light-emitting diodes of each line in accordance with the voltage measured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.