Optical filter having polyimide aerogel substrate and infrared radiation scattering particles
US11803001B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2020 |
| Grant date | Oct 31, 2023 |
| Priority date | — |
| Expiry date | Aug 25, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2207/109
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention relates to broadband and tunable infrared (IR)-blocking optical filters for millimeter and sub-millimeter astronomy composed of small diffusely scattered particles embedded in an aerogel substrate. The size of the scattering particles included in the aerogel filters can be tuned to give variable cutoff frequencies. In one embodiment, the aerogel scattering optical filters of the present invention have ultra-low density and index of refraction (typically n<1.15), removing the need for anti-reflection coatings that limit bandwidth and increase filter complexity, and allowing for high transmission across an ultra-broad band from zero frequency to above 1 THz, and as much as 10 THz.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.