Broadband cholesteric optical device having a broadband cholesteric layer, a positive C-plate and a negative C-plate
US6175400A · kind A · utility
37Cited by
23References
35Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 22, 1998 |
| Grant date | Jan 16, 2001 |
| Priority date | — |
| Expiry date | Jan 22, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/133634
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A broadband cholesteric optical device such as a polarizer or a spectral filter includes a broadband cholesteric layer, for instance, of a graded pitch type such that the cholesteric pitch increases monotonically from one surface of the film to the other surface. In order to improve the off-axis performance, a compensator is provided in the form of a positive birefringence film whose optic axis is substantially perpendicular to the film. Another negative birefringence film whose optic axis is also perpendicular to the film may also be provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.