Low cost color cube for liquid crystal light valve projector
US5917560A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 28, 1995 |
| Grant date | Jun 29, 1999 |
| Priority date | — |
| Expiry date | Nov 28, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/149
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid crystal projector and color beamsplitter that comprises a single X-cube beamsplitter that transmits both incident and exit light beams. One half of the beamsplitter divides incident white light into three primary colors, and the other half of the beamsplitter combines the primary colors to produce white light that is used for projection. More specifically, the projector comprises a light source for projecting white light, and the color beamsplitter is disposed to receive the white light. The beamsplitter comprises four (right angle) prisms that each comprise a base and two sides, and that are disposed such that the sides of the prisms are adjacent each other. The incident white light is separated by the prisms and coupled along three separate light paths corresponding to red, green and blue light paths. Apparatus such as a plurality of mirrors, or an optical link, for example, are provided for coupling the red, green and blue light back toward the beamsplitter. The red, green and blue light returned toward the beamsplitter is combined by the beamsplitter to produce white light that is transmitted as projected light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.