Method and apparatus for driving light emitting polymer displays
US7009603B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2002 |
| Grant date | Mar 7, 2006 |
| Priority date | — |
| Expiry date | Oct 8, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2330/021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for driving light emitting polymer (PolyLED) displays is provided. Because PolyLED displays exhibit high capacitance characteristics, pre-charge current is injected to bring the diode up to near its operating current prior to enabling the diode. Thus, time and power is not wasted charging and discharging the high capacitance that is inherent in PolyLED displays and life of the diodes are prolonged because the diodes are not required to swing the full voltage range during each cycle. In addition, since older diodes need more voltage to produce the same current thus the same light intensity as newer diodes, an embodiment of the present invention adds an adaptive power generation system that actively monitors and adjusts power as necessary in order to generate constant amount of light (i.e., constant current) from all the diodes in the display.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.