Augmented reality display system with variable focus
US9927614B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 29, 2015 |
| Grant date | Mar 27, 2018 |
| Priority date | — |
| Expiry date | Feb 19, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/294
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A near-eye optical display system that may be utilized in augmented reality applications and devices includes a diffractive waveguide having diffractive optical elements (DOEs) configured for in-coupling, exit pupil expansion, and out-coupling. An electrically-modulated tunable liquid crystal (LC) lens is located between the diffractive grating and the eyes of the user. A polarizing filter is located on the other side of the diffractive grating so that light from the real world enters the system with a particular polarization state, for example, TM-polarized. The tunable LC lens is configured to impart variable focus on light that has an opposite polarization state, for example TE-polarized. The optical display system is arranged to be polarization-sensitive so that virtual images from an imager are out-coupled from the diffractive waveguide with TE-polarization. The tunable LC lens may thus impart variable focus to the virtual images due to the lens' sensitivity to TE-polarization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.