Fluroescent lamps at full front surface luminance for backlighting flat panel displays
US6157143A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1999 |
| Grant date | Dec 5, 2000 |
| Priority date | — |
| Expiry date | Mar 2, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/3922
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A back-light assembly for a liquid crystal display (LCD) includes an LCD display screen and at least one cold cathode fluorescent lamp positioned for illuminating a back-side of the display screen. A reflector positioned adjacent the lamp reflects light toward the display screen. A light diffuser is positioned between the lamp and the display screen; and a power controller regulates current supplied to the lamp from an external power source so as to establish a predetermined luminance level at the display screen. A light level sensor provides a signal representative of the luminance output of the lamp to the controller so as to regulate lamp current to maintain the predetermined luminance level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.