Optical compensator including an o-plate for super-twist nematic liquid crystal display
US5557434A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1994 |
| Grant date | Sep 17, 1996 |
| Priority date | — |
| Expiry date | Sep 30, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/133632
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An improved normally white super-twist nematic (OMI) liquid crystal display exhibits a dramatically improved horizontal viewing angle as compared to conventional OMI displays. The display's liquid crystal cell has a twist angle greater than about 180.degree. and less than about 270.degree., preferably between 220.degree. and 250.degree., and a phase retardation of between 500 nanometers (nm) and 850 nm. The improved display includes a novel compensator which incorporates, as one of its compensation elements, a positively birefringent oblique compensator layer (referred to as an O-plate compensator layer). Additionally, a positively birefringent A-plate compensator layer and one or more negatively birefringent C-plate compensator layers may be used in the display.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.