Light scattering light valve projection apparatus
US5610735A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 1994 |
| Grant date | Mar 11, 1997 |
| Priority date | — |
| Expiry date | May 26, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1334
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A light valve projection apparatus includes a light source, a light valve used for forming optical images in response to a change in light scattering conditions in the light valve of light irradiated from the light source, a projection lens for projecting the optical images on a screen, and a shield for shielding the optical images formed at or near a pupil of the projection lens. If the brightness of light exiting from the light valve, which is in a light scattering state, in a direction tilted by .theta. degrees from a normal dissection of the light valve is assumed to be half as bright as the light outgoing in the normal direction at .theta..sub.1/2, .theta..sub.1/2 of the light valve is less than 23.degree.. The light valve may be a polymer dispersion liquid crystal display panel. When the polymer dispersion liquid crystal display panel is in a transparent state, light transmitted through the liquid crystal display panel is shielded by the shield, thus showing a black display on a screen. When the polymer dispersion liquid crystal display panel is in a light scattering state, light is scattered by the panel so that images formed in the panel are enlarged and projected by way of…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.