Beam dividing elements permitting projection of an image with high contrast
US6052231A · kind A · utility
32Cited by
4References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 19, 1999 |
| Grant date | Apr 18, 2000 |
| Priority date | — |
| Expiry date | Jan 19, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/283
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical element useful in optical systems such as liquid crystal optical display devices which is capable of projecting images having a high degree of contrast is provided. The optical element comprises a set of prisms whose coatings are designed to cancel one component of the depolarization in the light the prisms deliver. The other depolarization component is removed by returning the light to the projection lens through the same sequence of color-dividing coatings in reverse order. Hence, the optical element eliminates the depolarization components by employing double-pass propagation of polarized light therethrough.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.