Projection optical system for coupling image light to a near-eye display
US8873149B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Jan 28, 2013 |
| Grant date | Oct 28, 2014 |
| Priority date | — |
| Expiry date | Jan 28, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/0081
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Technology is described for a projection optical system which optically couples image light from an image source to a near-eye display (NED) of a wearable near-eye display device. The projection optical system and the image source make up a projection light engine. Light from the image source is directed to a birdbath reflective optical element which is immersed in high index glass. The image light is reflected and collimated by the birdbath element and travels outside a housing of the projection light engine forming an external exit pupil, meaning the exit pupil is external to the projection light engine. A waveguide optically couples the image light of the external exit pupil. An example of a waveguide which can be used is a surface relief grating waveguide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.