Broadband flat optical elements and methods of manufacture
US10365535B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 2017 |
| Grant date | Jul 30, 2019 |
| Priority date | — |
| Expiry date | Dec 28, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2370/16
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Flat optical elements including a multi-level metasurface stack having two or more metasurface levels. Each metasurface level includes an arrangement of nanostructures, or protrusions, of one or more optically transmissive materials. A metasurface level may further include another optically transmissive material between the nanostructures, achieving a desired index contrast. Another metasurface level including additional nanostructures may be over a planar surface of this additional transmissive material. Another optically transmissive material may be between the additional nanostructures. This architecture may be followed for any number of levels, (e.g., a bi-layer, tri-layer, etc.). Each metasurface within the multi-level metasurface structure may be tuned to a particular optical wavelength. Such a multi-level metasurface may have greater bandwidth and/or achieve higher optical efficiency for a given band than a single metasurface. Molding techniques may be employed in metasurface fabrication to reduce the starting material cost and fabrication cost.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.