Angle of view of a LCD screen by a novel birefringent film stacking
US6587171B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2001 |
| Grant date | Jul 1, 2003 |
| Priority date | — |
| Expiry date | Jan 29, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/133634
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention relates to a display device with a liquid-crystal cell comprising a twisted nematic liquid-crystal layer (40) placed between two crossed polarizers (46, 48) and comprising, between the liquid-crystal layer and at least one of the polarizers, a structure for compensating for the variations in contrast of the cell according to the angle of observation. This structure comprises at least two superposed negative uniaxial media such that the extraordinary optical axis of one medium (44, 42) is parallel to the normal to the cell and that of the other medium (43, 41) is inclined with respect to this normal on the one hand and with respect to the plane of the cell on the other. This compensating structure includes an additional layer (50, 49) of a positive uniaxial birefringent material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.