Fresnel antenna

1. A Fresnel antenna, comprising:

a plurality of Fresnel elements spaced to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, or selected wavelengths other than the attenuated wavelengths.

2. The Fresnel antenna as defined in claim 1 , wherein the concentrated electromagnetic waves have wavelengths within a band including infra-red light, visible light, ultra-violet light, or combinations thereof.

3. The Fresnel antenna as defined in claim 1 , wherein adjacent elements of the plurality of Fresnel elements are spaced from about 300 nm to about 850nm apart.

4. An electromagnetic wave detector system, comprising:

an electromagnetic wave detector; and

the Fresnel antenna as defined in claim 1 operatively connected to the electromagnetic wave detector.

5. The electromagnetic wave detector system as defined in claim 4 wherein the electromagnetic wave detector is a photo detector.

6. An electromagnetic wave detector system, comprising:

an electromagnetic wave detector; and

a Fresnel antenna operatively connected to the electromagnetic wave detector, the Fresnel antenna including:

a plurality of Fresnel elements spaced to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths;

wherein the electromagnetic wave detector is a PIN photodiode or an avalanche photodetector.

7. The electromagnetic wave detector system as defined in claim 4 , further comprising at least one additional Fresnel antenna, wherein the Fresnel antennae are operatively disposed in a stack.

8. The Fresnel antenna as defined in claim 1 , further comprising:

an electromagnetic wave amplifying layer disposed in contact with the plurality of Fresnel elements; and

a metal plasmon collector layer disposed in contact with the electromagnetic wave amplifying layer and spaced from the Fresnel elements by the electromagnetic wave amplifying layer.

9. The Fresnel antenna as defined in claim 8 , further comprising a dielectric substrate in contact with the metal plasmon collector layer.

10. The Fresnel antenna as defined in claim 8 , wherein the electromagnetic wave amplifying layer is formed from Group III-V semiconductors, glass with erbium doping, or combinations thereof.

11. The Fresnel antenna as defined in claim 8 wherein the metal plasmon collector layer has a metallic surface contacting the wave amplifying layer, and includes plasmon collecting notches formed in the metallic surface, wherein each of the notches is substantially aligned with a respective adjacent Fresnel element.

12. A Fresnel antenna, comprising:

a plurality of Fresnel elements spaced to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths;

a flexible substrate operatively connected to the Fresnel elements; and

a MEMS driver operatively connected to the flexible substrate, wherein the MEMS driver is configured to selectively flex the substrate, thereby selectively adjusting the spacing between the Fresnel elements;

wherein the antenna is selectively tuned.

13. A Fresnel antenna, comprising:

a plurality of Fresnel elements spaced to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths;

a plasmonic collector electrically or electromagnetically connected to the Fresnel elements, wherein the Fresnel elements are formed from metal; and

at least one plasmonic waveguide electrically or electromagnetically connected to the plasmonic collector.

14. The Fresnel antenna as defined in claim 13 wherein there is a plurality of concentrated electromagnetic wavelengths, with one wavelength that is smallest, wherein the plasmonic collector is an aperture substantially centered within the Fresnel elements, and wherein the aperture has an effective diameter smaller than one half of the smallest concentrated electromagnetic wavelength.

15. The Fresnel antenna as defined in claim 13 wherein there is a plurality of concentrated electromagnetic wavelengths, with one wavelength that is largest, and wherein the antenna further comprises:

a plurality of semiconductor Fresnel elements spaced radially from the metallic Fresnel elements wherein each of the semiconductor Fresnel elements has a diameter larger than the largest concentrated electromagnetic wavelength; and

at least one PIN diode structure integrated with at least one of the plurality of semiconductor Fresnel elements, the at least one PIN diode structure configured to allow the semiconductor Fresnel elements to be electrically pumped to amplify the concentrated electromagnetic waves.

16. A two-dimensional array of the Fresnel antennae as defined in claim 1 .

17. A method for harvesting electromagnetic signals, comprising:

providing a plurality of Fresnel elements spaced to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths;

coupling the amplified electromagnetic waves with plasmonic waves in the plurality of Fresnel elements;

electrically or electromagnetically connecting a plasmonic collector to the Fresnel elements;

electrically or electromagnetically connecting a plasmonic waveguide to the plasmonic collector; and

using plasmonic waves from the plasmonic waveguide as harvested electromagnetic signals.

18. The method as defined in claim 17 , further comprising operatively stacking layers of the plurality of Fresnel elements, thereby increasing gain.

19. The method as defined in claim 17 , further comprising:

operatively disposing the plurality of Fresnel elements on a flexible substrate; and

selectively adjusting spacing between adjacent Fresnel elements by flexing the substrate, thereby providing a tunable Fresnel antenna.

20. The method as defined in claim 19 , further comprising:

operatively connecting at least one MEMS driver to the flexible substrate; and

tuning the spacing by flexing the substrate with the MEMS driver.

21. The method as defined in claim 17 wherein the Fresnel elements are metallic, and wherein the method further comprises:

disposing a plurality of semiconductor Fresnel elements spaced radially from the metallic Fresnel elements; and

amplifying the concentrated electromagnetic waves via the semiconductor Fresnel elements.

22. The method as defined in claim 21 , further comprising:

operatively disposing the plurality of metallic Fresnel elements and semiconductor Fresnel elements on a flexible substrate; and

selectively adjusting spacing between adjacent metallic Fresnel elements and between adjacent semiconductor Fresnel elements by flexing the substrate, thereby providing a tunable Fresnel antenna.

23. The method as defined in claim 21 wherein there are at least two layers, each of the at least two layers including the plurality of metallic Fresnel elements and the plurality of semiconductor Fresnel elements, and wherein the method further comprises increasing gain by operatively stacking the at least two layers.

24. A method for harvesting electromagnetic signals, comprising:

providing a two-dimensional array of antenna cells, each antenna cell including a plurality of metallic Fresnel elements spaced to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths;

disposing a plurality of semiconductor Fresnel elements spaced radially from the metallic Fresnel elements in at least one cell;

amplifying the concentrated electromagnetic waves via the semiconductor Fresnel elements in the at least one cell;

coupling the amplified electromagnetic waves with plasmonic waves in the metallic Fresnel elements in at least one other cell that is the different from, or the same as the at least one cell;

electrically or electromagnetically connecting a plasmonic collector to the metallic Fresnel elements in the at least one other cell;

electrically or electromagnetically connecting a plasmonic waveguide to the plasmonic collector in the at least one other cell; and

using plasmonic waves from the plasmonic waveguides as the harvested electromagnetic signals.

25. A Fresnel antenna, comprising:

a plurality of Fresnel elements spaced to selectively attenuate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths, and to concentrate electromagnetic waves having a predetermined wavelength, selected wavelengths, or range of wavelengths other than the attenuated wavelengths;

wherein the concentrated electromagnetic waves have wavelengths within a band including ultra-violet light.