Folded projection system
US10802291B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 2019 |
| Grant date | Oct 13, 2020 |
| Priority date | — |
| Expiry date | Apr 9, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/22
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A compact folded projection system is described that includes a laser light source, a folded lens system comprising a lens stack including two or more refractive lenses and a light folding element (e.g., a prism), and a diffractive beam splitter that includes at least one diffractive surface. The light folding element provides a “folded” optical axis for the lens system to reduce the Z-height of the projection system, for example to within a range of 1.7 to 4 millimeters (e.g., 2 millimeters in some implementations). The laser light source emits light that is refracted by the lens stack to the folding element. The folding element redirects the light to the beam splitter which replicates the light into N×M duplications or tiles to thus generate a larger field of view (FOV) than the internal FOV of the lens system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.