Folded optical system adapted for head-mounted displays
US6400493B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1999 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | Oct 26, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/30
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical imaging assembly for imaging light from a display. The optical assembly is constructed from first and second linear polarization filters, first and second lenses that are preferably concave-convex lenses, and first and second ¼ wave plates. The first linear polarization filter passes light polarized in a first direction, and second linear polarization filter passes light polarized in a second direction that is orthogonal to the first direction. A folded imaging assembly is constructed from the first and second lenses and the first ¼ wave plate. The first and second lenses have partially reflecting coatings on one surface of each lens. The folded imaging assembly and the second ¼ wave plate are located between the first and second linear polarization filters. In the preferred embodiment of the present invention, the first ¼ wave plate has a birefringence axis that is orthogonal to the birefringence axis of the second ¼ wave plate and the two ¼ wave plates are constructed from the same material. The partially reflective coating of one of the first and second lenses preferably includes a material having a reflectivity that depends o…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.