Polarization recovery system for projection displays
US7002745B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 18, 2005 |
| Grant date | Feb 21, 2006 |
| Priority date | — |
| Expiry date | Feb 18, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3152
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A polarization recovery system polarizes input light for use with an LCD imager. The polarization recovery system converts light of the wrong polarity to the correct polarity to add to the illumination of the LCD imager. The polarization recovery system may include: (1) an output waveguide that receives polarized light energy from the system; (2) a polarized beam splitter that receives the light energy from the input waveguide, transmitting lights energy of a first polarization type and reflecting light energy of a second polarization type, and (3) a wave plate that modifies the polarization of either the transmitted or reflected light energy to that of the correct polarization. The polarization recovery system may include one or more “gaps” of optically clear material positioned between the optical components to encourage total internal reflection and minimize the loss of the optical energy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.