High contrast PDLC transmission gratings and method of manufacture
US6654072B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2001 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | Dec 7, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2201/305
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A PDLC transmissive phase grating utilizing nematic liquid crystal materials confined in a polymer matrix. The PDLC grating operates in the Bragg regime and switches between diffracting and non-diffracting states via an applied electric field. The grating is made up of a PDLC grating film contained within a cell. The PDLC film has a spatially periodic distribution of grating planes which includes polymer-rich regions and liquid crystal-rich regions, wherein the major constituent of the polymer-rich regions is a polymer, and wherein the liquid crystal constituent concentration within the liquid crystal-rich regions is greater than the liquid crystal constituent concentration within said polymer-rich regions. The PDLC transmission phase grating is rendered substantially transparent when subjected to an electric field during the application of light that is p-polarized and incident on the grating at Bragg angle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.