Optical systems having angle-selective transmission filters
US12298505B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2021 |
| Grant date | May 13, 2025 |
| Priority date | — |
| Expiry date | Aug 24, 2043 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2027/0174
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An electronic device may include an emissive display panel that emits light. The light may propagate along an optical path extending to an eye box. A waveguide with an input coupler and an output coupler may be interposed on the optical path. An angle-selective transmission filter (ASTF) may be interposed on the optical path and may filter the emitted light as a function of angle to remove high-angle light from the optical path before the light is provided to the output coupler. The ASTF may include diffractive grating structures such as thin-film holograms, volume holograms, or surface relief gratings, louvered mirrors, multi-layer coatings, or a pinhole array. This ASTF may serve to minimize stray light within the display, thereby optimizing the contrast and the modulation transfer function (MTF) of the display.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.