Polymer dispersed liquid crystal display device with asymmetric optical diffuser
US5629785A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 1995 |
| Grant date | May 13, 1997 |
| Priority date | — |
| Expiry date | May 4, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1334
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A display device comprises a polymer dispersed liquid crystal film that includes one or more translucent regions and one or more transparent regions. The back side of the polymer dispersed liquid crystal film is illuminated by collimated light. The front side of the polymer dispersed liquid crystal film is optically coupled to an asymmetric optical diffuser. The asymmetric optical diffuser comprises a plurality of light paths that transmit collimated light emanating through a transparent region of the film, but excludes diffuse light emanating from a translucent region. A preferred asymmetric optical diffuser comprises glass microspheres in a black matrix. In this manner, the asymmetric diffuser substantially improves contrast between a transparent region and a translucent region of a display.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.