Polarization recapture system for liquid crystal-based data projectors
US6739723B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 2001 |
| Grant date | May 25, 2004 |
| Priority date | — |
| Expiry date | Jun 26, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/315
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projection display system includes a light source emitting a randomly polarized light and a polarization recapture system including a tunnel integrator and a transmitting/reflecting polarizer coupled to the output end of the tunnel integrator. The input end of the tunnel integrator includes an input aperture and a reflective inside surface coated with a quarter wave retarder. In operation, the randomly polarized light enters the tunnel integrator through the input aperture. The polarization recapture system transmits light having a first polarization as polarized light output and recycles light having a second polarization orthogonal to the first polarization. The light having the second polarization is reflected by the transmitting/reflecting polarizer back into the tunnel integrator. The polarization recapture system recycles the light having the second polarization by reflecting and reorienting the light having the second polarization to light of the first polarization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.