Elliptical diffusers used in displays
US7430358B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 2006 |
| Grant date | Sep 30, 2008 |
| Priority date | — |
| Expiry date | Apr 19, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0046
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A backlit light display comprises a light guide panel, a prismatic film, an asymmetric top diffuser and an LCD. A linear light source is disposed along a side face of the light guide panel. Light from the linear light source is transmitted though the light guide panel where it is spread and uniformly output through a front face to the prismatic film. Light incident on the prismatic film is redirected more along a first direction than along a second direction. This light is directed more normal to the LCD. An asymmetric diffuser is applied between the prismatic film and the LCD panel to smear the periodic information from the prismatic film and eliminate the Moiré fringe pattern resulting from interference between the periodic structure of the prismatic film and the periodic arrangement of pixels in the LCD. The asymmetric diffuser is aligned with respect to the prismatic film such that it scatters and spreads light more in a second direction than the first direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.