Polarizing beam splitter
US6721096B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 2002 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Nov 15, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2995/0034
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical imaging system including a wide-angle Cartesian polarizing beam splitter, light valve illumination optics having an f/#≦2.5, and at least one reflective light valve. The Cartesian polarizing beam splitter (PBS) has a structural orientation defining fixed polarization axes. The use of a Cartesian PBS allows the development of systems using curved PBS that provide higher light output and/or replace or augment other optical components. By recognizing and advantageously applying properties of wide-angle Cartesian polarizers, the present invention discloses a high-efficiency optical imaging system capable of functioning at f/#'s equal to or below f/2.5 while maintaining a contrast ratio of at least 100 to 1, or, more preferably, 150 to 1 in a projection system configuration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.