Bistable nematic liquid crystal device
US7471362B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 23, 2000 |
| Grant date | Dec 30, 2008 |
| Priority date | — |
| Expiry date | Feb 26, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/03
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid crystal device comprises a layer (2) of a nematic liquid crystal material contained between two cell walls (3, 4) each carrying electrode structures (6, 7) and an alignment surface (20, 21). The alignment layer (20, 21) on one or both cell wall (4), is formed of a plurality of small (<15 μm) surface features each separably capable of providing a bistable pretilts and an alignment direction and collectively causing larger variations of molecular orientation across the layer (2). The device may be switched between a light transmissive state and a light non-transmissive state. The small surface features may be areas of grating (21), protrusions (25), or blind holes (26), separated by mono stable flat surfaces (Fm) coated with a homeotropic alignment layer. Preferably, the grating etc provides bistable switching operation between a low surface tilt and high surface tilt, and the low tilt alignment direction varies between adjacent grating areas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.