Liquid crystal display
US6362862B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1997 |
| Grant date | Mar 26, 2002 |
| Priority date | — |
| Expiry date | Apr 25, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7441
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A liquid crystal display featuring excellent visibility with both good brightness and a high contrast ratio uses a projection optical system in which a polarizing plate, a first phase plate and a second phase plate in which the retardation of each of the phase plates and a gradient of wavelength dispersion of the retardation can be freely set, a liquid crystal layer, and a reflection plate are arranged in parallel and a transmitted light is reflected by the reflection plate. A gradient of one of the phase plates is set to an extremely steep gradient, a gradient of the other phase plate is set to an extremely flat gradient, and the wavelength dispersion of a retardation composite value obtained from the liquid crystal layer and the two phase plates is approximated to a retardation curve expressed by a relational expression of (0.25+0.5n)&lgr;, where (n) is an integer and &lgr; is a wavelength (nm) of the transmitted light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.