Film with partial pre-alignment of polymer dispersed liquid crystals for electro-optical devices, and method of forming the same
US4944576A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1988 |
| Grant date | Jul 31, 1990 |
| Priority date | — |
| Expiry date | Mar 21, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A polymer dispersed liquid crystal (PDLC) film, along with various fabrication methods that enable partial prealignment of the film's LC bubbles, are described. The film is formed with a matrix of liquid crystal bubbles. Individual liquid crystals within the bubbles are partially, but substantially less than fully, aligned in a given direction. Partial alignment is attained by the controlled application of an electric or magnetic field, or a mechanical flow, during photopolymerization. The resulting films retain the positive qualities of prior PDLCs, and in addition exhibit generally lower threshold and operating voltages, and can be used as tunable birefringent films in the infrared region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.