Switchable diffractive optical element and waveguide containing the same
US11428938B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 2019 |
| Grant date | Aug 30, 2022 |
| Priority date | — |
| Expiry date | Aug 11, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2027/0178
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical device includes a light source assembly configured to generate an image light; and at least one waveguide including an in-coupling element and an out-coupling element configured to transmit, via the at least one waveguide, a plurality of light fields of the image light to an eye-box of the optical device, in a time-multiplexing manner. At least one of the in-coupling element or the out-coupling element includes at least one switchable diffractive optical grating, which includes a surface relief grating (SRG) filled with an optically anisotropic material having a first principal refractive index along a groove direction of the SRG and a second principal refractive index along an in-plane direction perpendicular to the groove direction. One of the first and second refractive principal refractive indices substantially matches a refractive index of the SRG, and the other mismatches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.