Energy absorbing materials
US9322953B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 18, 2011 |
| Grant date | Apr 26, 2016 |
| Priority date | — |
| Expiry date | Jun 1, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24355
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An indefinite metamaterial where the surface or immediate subsurface region is roughened or disordered has improved coupling of electromagnetic waves incident on the medium. This also means that the amount of energy reflected by the material is reduced. Such a reduction in reflection may reduce the radar observability of a structure with a metamaterial surface, or increase the amount of energy coupled to a detector. An indefinite metamaterial has at least one of the components of the permittivity tensor that is different in sign from the other axes, and in a uniaxial indefinite material this differing axis is oriented perpendicular to the surface of the material. The disorder has scale dimensions of the order of a wavelength and may be random or periodic.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.