Liquid crystal light modulating materials with selectable viewing angles
US4890902A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 1988 |
| Grant date | Jan 2, 1990 |
| Priority date | — |
| Expiry date | Feb 23, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249997
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A light modulating material comprising phase-separated microdroplets of liquid crystal in a light transmissive, synthetic resin matrix wherein the index of refraction n.sub.p of the matrix is matched or mismatched to an index of refraction N.sub.o of the liquid crystal optical axis of the microdroplets so that when the microdroplet director is aligned relative to a surface of the material, maximum transmission of light occurs at a selected oblique angle relative to the surface of the material or at a selected narrow angle about the perpendicular to the surface of the material. Such matching or mismatching of indices of refraction may be accompanied by phase separation in an external magnetic or electric field, or by shaping the liquid crystal microdroplet into an ovoid or the like during or after phase separation to align the microdroplet directors thereby endowing the material with a permanent and movable viewing angle. One or more sheets of the improved light modulating material may be incorporated into a window or an electrooptic display device to provide angularly discriminating windows or displays that are transparent or visible only at selected angles of view and that are opa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.