Birefringence-compensated liquid crystal display and projection system using same
US7542194B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 2005 |
| Grant date | Jun 2, 2009 |
| Priority date | — |
| Expiry date | Sep 13, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7441
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projection system includes an image-forming device and a polarizing beamsplitter. Illumination light illuminates the image-forming device via the first polarizing beamsplitter. A retardation element is disposed between the image-forming device and the polarizing beamsplitter. A bias controller applies a bias to pixels of the image-forming device in the dark state so as to substantially maximize contrast in image light reflected from image-forming device. In some arrangements, the volume between the polarizing beamsplitter and the image-forming device is sealed, with the retarding element being disposed within the sealed volume and being attached to either the polarizing beamsplitter or the image-forming device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.