Holographic illumination system
US6317228A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2001 |
| Grant date | Nov 13, 2001 |
| Priority date | — |
| Expiry date | Mar 14, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/13342
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed is an apparatus and method of illuminating an image display via an electrically switchable holographic optical element. The method includes a first electrically switchable holographic optical element (ESHOE) receiving illumination light. The first ESHOE comprises oppositely facing front and back surfaces. The first ESHOE diffracts a first component (e.g., p-polarized blue light) of the illumination light while transmitting the remaining components of the illumination light without substantial alteration. An image display is provided and receives the diffracted first component. In response to receiving the diffracted first component, the image display emits image light. The first ESHOE receives and transmits this image light without substantial alteration. In one embodiment, the diffracted first component emerges from the first ESHOE at the back surface thereof, and the first ESHOE receives the image light at the back surface thereof so that the image light is received by the first ESHOE in a direction substantially parallel to a direction at which the diffracted first component emerges from the back surface of the first ESHOE.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.