Multi-layer diffractive eyepiece with wavelength-selective reflector
US10725223B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 2017 |
| Grant date | Jul 28, 2020 |
| Priority date | — |
| Expiry date | Sep 21, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3144
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An eyepiece for projecting an image to an eye of a viewer includes a waveguide configured to propagate light in a first wavelength range, and a grating coupled to a back surface of the waveguide. The grating is configured to diffract a first portion of the light propagating in the waveguide out of a plane of the waveguide toward a first direction, and to diffract a second portion of the light propagating in the waveguide out of the plane of the waveguide toward a second direction opposite to the first direction. The eyepiece furthers include a wavelength-selective reflector coupled to a front surface of the waveguide. The wavelength selective reflector is configured to reflect light in the first wavelength range and transmit light outside the first wavelength range, such that the wavelength-selective reflector reflects at least part of the second portion of the light back toward the first direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.