Optical shifter and projection type optical display system
US7106389B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2003 |
| Grant date | Sep 12, 2006 |
| Priority date | — |
| Expiry date | Nov 9, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/13363
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical shifter includes first and second optical shifting sections, each of which can transmit an incoming light ray after having shifted its optical axis and which are arranged such that a light ray transmitted through the first optical shifting section enters the second optical shifting section. Each of the shifting sections includes: a liquid crystal element including a liquid crystal cell, which selectively changes the polarization direction of the incoming light ray responsive to a voltage applied thereto; and a birefringent element, which receives the light ray transmitted through the liquid crystal element and which exhibits one of different refractive indices according to the polarization direction of the incoming light ray. The magnitude of shift caused by the first optical shifting section between the optical axes of the incoming and outgoing light rays is substantially twice greater than that of shift caused by the second optical shifting section.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.