Reflective display including a frontlight with multiple stacked lightguides with a fold
US11275204B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 2020 |
| Grant date | Mar 15, 2022 |
| Priority date | — |
| Expiry date | Oct 7, 2040 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49826
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A display includes a reflective spatial light modulator with an active area; a plurality of lightguides stacked above the active area; and a light source positioned to emit light that propagates into the plurality of lightguides such that the light is totally internally reflected within each lightguide then extracted from each lightguide to illuminate the active area, wherein each lightguide is folded at a first fold. In a first embodiment, each of the plurality of lightguides include a core layer and an emitting region with a plurality of light extraction features arranged in a spatially varying pattern. In a second embodiment, each lightguide is a film-based light guide with a thickness between 0.005 millimeter and 0.175 millimeter. In a third embodiment, the light source is positioned behind the spatial light modulator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.