Outward coupling suppression in waveguide display
US11099309B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 2019 |
| Grant date | Aug 24, 2021 |
| Priority date | — |
| Expiry date | Jan 20, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/2955
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A pupil replication waveguide for a projector display includes a slab of transparent material for propagating display light in the slab via total internal reflection. A diffraction grating is supported by the slab. The diffraction grating includes a plurality of tapered slanted fringes in a substrate for out-coupling the display light from the slab by diffraction into a blazed diffraction order. A greater portion of the display light is out-coupled into the blazed diffraction order, and a smaller portion of the display light is out-coupled into a non-blazed diffraction order. The tapered fringes result in the duty cycle of the diffraction grating varying along the thickness direction of the diffraction grating, to facilitate suppressing the portion of the display light out-coupled into the non-blazed diffraction order.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.