Liquid crystal display device
US5751267A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1996 |
| Grant date | May 12, 1998 |
| Priority date | — |
| Expiry date | Feb 27, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2320/0276
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A liquid crystal device has a video interface having a reference value shifter and a level converter, which work as a gamma controller, and has a counter electrode signal generating circuit having a feedback amplifying circuit for adjusting peak-to-peak amplitude of a counter electrode signal on the basis of a control signal sent from a brightness adjuster. The reference value shifter shifts a reference value of polygonal-line approximation characteristics as much as a variation of the counter electrode signal amplitude on the basis of the control signal sent from the brightness adjuster. The level converter converts a level of an image signal in accordance with the polygonal-line approximation characteristics determined on the basis of the varying reference value, and thus compensates non-linearity of light transmittance index characteristics of liquid crystal to an applied voltage. Consequently, it is possible to provide the small, thin and cheap liquid crystal display device having a display brightness adjusting function capable of producing correct gradation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.