High efficiency field-sequential color projector using two SLMs
US5921650A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1998 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | Feb 27, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A display is disclosed operating in a field-sequential color mode having first and second light valves which are simultaneously illuminated with different color beams having different polarizations 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 white light into the simultaneous different color beams. A retardation film for converting the polarization of colors reflected from the back surface from a first polarization to a second polarization. The wheel is rotated for sequentially illuminating the light valves with different colors of different polarizations simultaneously. The display further includes a polarizing beam splitter assembly for directing the different color light beams from the wheel to the light valves and directing the image forming light to the projection lens. The polarizing beam splitter assembly includes a plurality of polarizing beam splitter sub-assemblies. A clean-up polarizer for absorbing the first or second polarizati…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.