Normally white LCD including first and second biaxial retarders
US6229588A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1998 |
| Grant date | May 8, 2001 |
| Priority date | — |
| Expiry date | Mar 26, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2413/13
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A normally white liquid crystal display is provided with a positively birefringent uniaxial retardation film having a retardation value of from about 100-200 nm. The retardation film is provided on one side of the liquid crystal layer, the liquid crystal being sandwiched between a pair of orientation or buffing films which orient the liquid crystal molecules adjacent thereto in predetermined directions. The optical axis of the retardation film is rotated from about 2.degree.-20.degree., most preferably from about 6.degree.-10.degree. relative to the buffing direction on the opposite side of the liquid crystal layer. This rotation of the retardation film optical axis allows for the high contrast ratio viewing zone of the display to be shifted vertically into either the positive or negative vertical viewing region depending upon the direction of rotation of the retardation film optical axis. Alternatively, biaxial retardation films having similar retardation values may be utilizied according to the teachings of this invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.