Reflective LCD projection system using wide-angle Cartesian polarizing beam splitter and color separation and recombination prisms
US7023602B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2000 |
| Grant date | Apr 4, 2006 |
| Priority date | — |
| Expiry date | Oct 18, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3167
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical imaging system including an illumination system, a Cartesian PBS, and a prism assembly. The illumination system provides a beam of light, the illumination system having an f/# less than or equal to 2.5. The Cartesian polarizing beam-splitter has a first tilt axis, oriented to receive the beam of light. A first polarized beam of light having one polarization direction is folded by the Cartesian polarizing beam splitter and a second polarized beam of light having a second polarization direction is transmitted by the Cartesian polarizing beam splitter. The Cartesian polarizing beam splitter nominally polarizes the beam of light with respect to the Cartesian beam-splitter to yield the first polarized beam in the first polarization direction. The color separation and recombination prism is optically aligned to receive the first polarized beam. The prism has a second tilt axis, a plurality of color separating surfaces, and a plurality of exit surfaces. The second tilt axis maybe oriented perpendicularly to the first tilt axis of the Cartesian polarizing beam-splitter so that the polarized beam is nominally polarization rotated into the second polarization direction with respec…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.