Liquid crystal device for generation and fast switching of high contrast images
US7907236B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Aug 22, 2007 |
| Grant date | Mar 15, 2011 |
| Priority date | — |
| Expiry date | Oct 19, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1412
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An electro-optic device including a liquid crystal material is disclosed, comprising antiferroelectric liquid crystals with large molecular tilt θ of about 45° degrees, disposed between two flat glass or polymer substrates. The liquid crystal molecules are preferably oriented parallel to the substrates (so-called HAF texture). The device is e.g. placed between two crossed polarizers so that in field-off conditions the impinging light is not passing through the device due to the isotropic optical properties of the antiferreoelectric liquid crystal aligned in HAF texture. An applied electric field induces a continuous transition of the optically isotropic antiferreoelectric (AF) state to ferroelectric (F) one which is birefringent enabling the transmission of light. The field-induced continuous switching between the optically isotropic antiferreoelectric state and the birefringent ferroelectric state enables the generation and fast switching of high contrast as well as generation of grey scale levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.