Intelligent LCD brightness control system
US5952992A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 19, 1997 |
| Grant date | Sep 14, 1999 |
| Priority date | — |
| Expiry date | Aug 19, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2360/144
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for automatically adjusting the brightness level of an LCD based on the ambient lighting conditions of the environment in which the LCD is being operated are disclosed. In a preferred embodiment, a photodetector located proximate the front of the LCD generates to brightness control circuitry signals indicative of ambient lighting conditions. These signals are correlated to predetermined automatic brightness control values for use in controlling the brightness level of the LCD. Once the ambient light signals have been used automatically to set the brightness level of the LCD, user-selection of a different brightness level, either higher or lower, will override the automatic brightness control setting. In an alternative embodiment, a first photodetector is located proximate the front of the LCD and a second photodetector is located proximate the back of the LCD. In this embodiment, the brighter ambient condition is used to control the brightness level of the LCD.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.