High efficiency two-SLM projector employing total-internal-reflection prism
US5863125A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 30, 1998 |
| Grant date | Jan 26, 1999 |
| Priority date | — |
| Expiry date | Jan 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7441
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A display is disclosed operating in a field-sequential color mode having at least two light valves which are simultaneously illuminated with different color beams having the same polarization provided from a color wheel. The light valves provide an image forming light to a projection lens for projecting the image forming light onto a screen. The wheel has front and back surfaces which are displaced from each other and have segments of different colors for separating a polarized light into the simultaneous different color beams when the different colors of the front and back color segments overlap. The two beams from the front and back surfaces are parallel to each other when the front and back surfaces are parallel. Alternatively, when the front and back surfaces meet to form a wedge, the two beams have different directions. The front and back color segments are offset relative to each other and each has clear segments so that one colored beam is provided to one of the light valves. The front and back clear segments are also offset relative to each other. The wheel is rotated for sequentially illuminating the light valves with different colors simultaneously.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.