LED backlight luminance sensing for LCDs
US7855708B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 2001 |
| Grant date | Dec 21, 2010 |
| Priority date | — |
| Expiry date | Dec 31, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2360/145
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A liquid crystal display (LCD) system having LED backlight luminance sensing is disclosed. An array of LEDs in a backlighting position includes a plurality of LED strings. At least one LED from at least one string is identified as a sampling LED. The light emitted from the sampling LED is detected via an optical path using a light sensor. The reading from the sensor is contrast with a command, which results in a power compensation to the array accordingly. In one embodiment, the system includes a sampling enclosure encasing the sampling LED and light sensor. The sampling LED's direction of emission is altered from the string and reflected from the inside of the enclosure. In another embodiment, the system includes a direct sensing optical path between the light sensor and the sampling LED.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.