Method and device for the polarizing of an LCD screen as a function of the ambient luminosity
US6650340B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 1998 |
| Grant date | Nov 18, 2003 |
| Priority date | — |
| Expiry date | Feb 26, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2360/144
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
To obtain improved readability of a liquid crystal display screen under varied conditions of ambient luminosity, it is possible to increase the dynamic range of variation of the polarizing voltage. However, this leads to an increase in the electrical power consumption and to contrast reversal defects. To prevent this phenomenon, it is proposed not to modify the dynamic range of variation of polarizing voltage but to shift this range towards the lower voltages when the ambient luminosity increases or towards the higher voltages when the ambient luminosity diminishes. Thus, the white level is favored under high ambient luminosity and the black level is favored under low or normal luminosity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.