Liquid crystal display device comprising reflective holographic
US5663816A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1996 |
| Grant date | Sep 2, 1997 |
| Priority date | — |
| Expiry date | Jan 30, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2222/36
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid crystal display device (30) that is illuminatable by diffuse ambient light comprises a liquid crystal panel (32) and a reflective holographic optical element (34). Diffuse ambient light illuminating the front side (36) of the liquid crystal panel and traversing the liquid crystal panel is received at a reflection site (66) and is redirected with a reflection pattern (68) to retraverse the liquid crystal panel to form a bright pixel for a display. By concentrating diffuse light within a preferential reflection pattern, the reflective holographic optical element provides enhanced brightness for viewing the display under ambient light conditions. In one aspect, the reflective holographic optical element is a transflector (158, 208) and is combined with an internal light source (170, 220) for illuminating the display using either reflected ambient light or backlighting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.