Method and apparatus for creating perfect microwave absorbing skins

Patent metadata

Field	Value
Publication number	US-9961812-B2
Application number	US-201414216768-A
Country	US
Kind code	B2
Filing date	Mar 17, 2014
Priority date	Mar 15, 2013
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A method and apparatus for producing a radio frequency absorber (RFA) or perfect microwave absorber (PMA) skin is described herein. A metamaterial layer may be applied to a low dielectric substrate. Resistive and capacitive components may then be added to the metamaterial layer. The metamaterial layer may then be formed into an RFA or PMA skin, which may then be applied to a multi-layered assembly for absorption of electromagnetic radiation in a frequency range such as the microwave frequency spectrum in a final product including but limited to cell phones, communication devices, or other electronic devices.

First claim

What is claimed is:

1. A method for producing a radio frequency absorber (RFA) skin, the method comprising:
applying a metamaterial, wherein the metamaterial includes an all-dielectric material having a first dielectric constant, to a substrate with a second dielectric constant to create a metamaterial layer;
adding resistive components to the metamaterial layer;
adding capacitive components to the metamaterial layer;
processing the metamaterial layer into a RFA skin; and
applying the RFA skin in a plurality of layers to an assembly for absorption of electromagnetic radiation in a targeted frequency range.

2. The method of claim 1 , wherein Gravure printing is used to apply the metamaterial to the substrate.

3. The method of claim 1 , wherein pad printing is used to apply the metamaterial to the substrate.

4. The method of claim 1 , wherein direct write, dip-pen nanolithography (DPN) or e-jet printing is used to apply the metamaterial to the substrate.

5. The method of claim 1 , wherein the targeted frequency range is a microwave frequency range.

6. The method of claim 1 , wherein the plurality of layers are thermoformed into a single sub-assembly prior to inclusion in the assembly.

7. The method of claim 1 , wherein the substrate includes spheres with unequal dielectric constants dispersed uniformly within a matrix, wherein the dielectric constant of the matrix is at least two orders of magnitude smaller than the dielectric constant of the spheres.

8. The method of claim 7 , wherein the matrix and spheres are used in an overmold for cable connectors.

9. The method of claim 7 , wherein the matrix and spheres are used in a thermoset cable covering for a group of cables.

10. The method of claim 7 , wherein the matrix and spheres are used in a planar sheet in an EMI absorbant layer in the assembly.

11. The method of claim 7 , wherein the spheres have different radii.

12. A radio frequency absorber (RFA) skin, prepared by a process comprising the steps of:
applying a metamaterial, wherein the metamaterial includes an all-dielectric material having a first dielectric constant, to a substrate with a second dielectric constant to create a metamaterial layer;
adding resistive components to the metamaterial layer;
adding capacitive components to the metamaterial layer;
processing the metamaterial layer into a RFA skin; and
applying the RFA skin in a plurality of layers to an assembly for absorption of electromagnetic radiation in a targeted frequency range.

13. The RFA skin of claim 12 , wherein Gravure printing is used to apply the metamaterial to the substrate.

14. The RFA skin of claim 12 , wherein pad printing is used to apply the metamaterial to the substrate.

15. The RFA skin of claim 12 , wherein direct write, dip-pen nanolithography (DPN) or e-jet printing is used to apply the metamaterial to the substrate.

16. The RFA skin of claim 12 , wherein the targeted frequency range is a microwave frequency range.

17. The RFA skin of claim 12 , wherein the plurality of layers are thermoformed into a single sub-assembly prior to inclusion in the assembly.

18. The RFA skin of claim 12 , wherein the substrate includes spheres with unequal dielectric constants dispersed uniformly within a matrix, wherein the dielectric constant of the matrix is at least two orders of magnitude smaller than the dielectric constant of the spheres.

19. The RFA skin of claim 18 , wherein the spheres have different radii.

20. A method for producing a perfect microwave absorber (PMA) skin, the method comprising:
printing a metamaterial, wherein the metamaterial includes an all-dielectric material having a first dielectric constant, on a substrate with a second dielectric constant to create a metamaterial layer;
adding resistive components to the metamaterial layer;
adding capacitive components to the metamaterial layer;
processing the metamaterial layer into a PMA skin; and
applying the PMA skin in a plurality of layers to an assembly for absorption of electromagnetic radiation in a microwave frequency range.

Assignees

• Flextronics Ap Llc

Inventors

• Suorsa Peter

Classifications

• H01Q17/002 Primary

  using short elongated elements as dissipative material, e.g. metallic threads or flake-like particles · CPC title

• G02B2207/121

  Antistatic or EM shielding layer · CPC title

• H01Q17/00

  Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems · CPC title

• H05K2201/083

  Magnetic materials · CPC title

• Y10T156/1002

  with permanent bending or reshaping or surface deformation of self sustaining lamina · CPC title