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Absorber for electromagnetic radiation

Assignee: Saint Gobain Isover G+H AG
•
Filing: 1970-11-10
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Granted: 1973-03-20
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Expires: 1990-11-10
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Abstract

Abstract A body designed to absorb electromagnetic radiation in the UHF, SHF and EHF includes a multiplicity of closely juxtaposed spheres, whose diameters lie between about 0.1 and 5 times the wavelength of that radiation, imbedded in a polymeric matrix and/or lodged in cavities of a cellular supporting structure. Each sphere has a nonconductive, preferably highly porous spherical core coated with one or more layers of radiationresponsive (electrically conductive and/or magnetically permeable) material each advantageously overlain by a protective dielectric coating. The conductivity and/or permeability of the coatings of successive strata of spheres may progressively diminish in the direction of propagation, toward the source of radiation, to approach the conditions of ambient air or free space.

Inventors

  • 👤 L Wesch

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 07:27
CPC Classifications
H; H01; H01Q; H01Q17/00; H01Q17/004

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 13 words
An absorber as defined in claim 1 wherein said layer is electrically conductive.
Claim 2
Dependent Claim 16 words
An absorber as defined in claim 2 wherein said layer incorporates a mass of carbonaceous particles.
Claim 3
Dependent Claim 13 words
An absorber as defined in claim 1 wherein said layer is magnetically permeable.
Claim 4
Dependent Claim 14 words
An absorber as defined in claim 4 wherein said layer incorporates low-remanence ferromagnetic particles.
Claim 5
Dependent Claim 25 words
An absorber as defined in claim 1 wherein each of said spheres further has an electromagnetically inert outer layer adjoining said layer of radiation-responsive material.
Claim 6
Dependent Claim 27 words
An absorber as defined in claim 1 wherein said body comprises a compartmented structure accommodating several groups of said spheres in respective compartments filled with said matrix.
Claim 7
Dependent Claim 31 words
An absorber as defined in claim 7 wherein said structure has solid walls forming said compartments in a plurality of tiers generally perpendicular to the direction of incidence of said radiation.
Claim 8
Dependent Claim 19 words
An absorber as defined in claim 1 wherein said core and said polymeric matrix have substantially the same composition.
Claim 9
Dependent Claim 47 words
An absorber as defined in claim 1 wherein said spheres are arrayed in a plurality of strata generally transverse to the direction of incidence of said radiation, said layer of radiation -responsive material having a conductivity which decreases progressively in successive strata toward the source of radiation.
Claim 10
Dependent Claim 17 words
An absorber as defined in claim 9 wherein said core and said matrix consist of foam polymer.
Claim 11
Dependent Claim 31 words
An absorber as defined in claim 1 wherein said core has a diameter upwards of 1 mm and said layer has a thickness of up to about one-tenth of said diameter.

References Cited (Backward Citations)

US2730597A Cited
US3038551A Cited
US3440655A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-03-19 1976-09-18 1977-03-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-03-19 1980-09-18 1981-03-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-03-19 1984-09-18 1985-03-20 $7700.00 Window Closed / Lapsed

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