Liquid crystal display comprising liquid crystal cell, linearly polarizing membrane, cholesteric liquid crystal layer and quarter wave plate
US6519017B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 2000 |
| Grant date | Feb 11, 2003 |
| Priority date | — |
| Expiry date | Jul 19, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2413/15
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid crystal display comprises a liquid crystal cell, a linearly polarizing membrane, a cholesteric liquid crystal layer and a quarter wave plate. The cholesteric liquid crystal layer is divided into two or more areas having different spiral pitches of cholesteric liquid crystal. The quarter wave plate comprises an optically anisotropic layer A and an optically anisotropic layer B. One of the optically anisotropic layers A and B is formed from liquid crystal molecules. The other is formed from liquid crystal molecules or made of a polymer film. The quarter wave plate gives a retardation value per wavelength within the range of 0.2 to 0.3 at each wavelength of 480 nm, 550 nm and 630 nm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.