Imaging devices including dielectric metamaterial absorbers and related methods
Imaging devices including dielectric metamaterial absorbers and related methods are disclosed. According to an aspect, an imaging device includes a support. The imaging device also includes multiple dielectric metamaterial absorbers attached to the support. Each absorber includes one or more dielectric resonators configured to generate and emit thermal heat upon receipt of electromagnetic energy.
1. An imaging device comprising:
a thermally insulating support;
a plurality of dielectric-only metamaterial absorbers disposed on a first side of the support and configured to emit heat upon receipt of electromagnetic energy,
wherein the plurality of absorbers are configured to transfer heat to the support such that transferred heat from each absorber is limited to a localized region around the absorber; and
an infrared camera configured to capture a composite thermal image of the localized regions.
2. The imaging device of claim 1 , wherein the absorbed electromagnetic energy is in a frequency range of approximately 90 gigahertz to 3 terahertz.
3. The imaging device of claim 1 , wherein in the emitted heat has an electromagnetic wavelength in a range of approximately 8 to 14 microns.
4. The imaging device of claim 1 , wherein the infrared camera faces a second side of the support opposite the first side of the support.
5. The imaging device of claim 1 , wherein the support is devoid of a ground plane.
6. The imaging device of claim 1 , wherein the support is made of one of polyimide, foam, aerogel, polytetrafluoroethylene, poly(methyl methacrylate), polydimethylsiloxane, and ceramic.
7. The imaging device of claim 1 , wherein the support has a thickness in the range of approximately 1-10 microns.
8. The imaging device of claim 1 , wherein the plurality of absorbers are substantially shaped as a cylinder.
9. The imaging device of claim 1 , wherein at least one of the plurality of absorbers is substantially shaped as one of a cone, a parabolic shape, an extruded cross, and a cubical shape.
10. The imaging device of claim 1 , wherein the plurality of absorbers are arranged in a rectangular or offset array.
11. The imaging device of claim 1 , wherein a distance between neighboring absorbers is in a range of about 118 microns or about 0.05-0.25 times a wavelength of the absorbed electromagnetic energy.
12. The imaging device of claim 8 , wherein the plurality of absorbers have a diameter of between about 120 microns and about 212 microns.
13. The imaging device of claim 1 , wherein the plurality of absorbers are made of one or silicon, gallium arsenide, germanium, indium phosphide, ceramic, zirconium dioxide, diamond, silicon nitride, barium strontium titanate, and titanium dioxide.
14. The imaging device of claim 3 , wherein the support has an emissivity of approximately 0.75 or higher in the emitted heat range.
15. The imaging device of claim 1 , comprising a second layer of absorbers stacked on top of the plurality of absorbers.
16. The imaging device of claim 1 , wherein the absorbers and support are contained within a vacuum or near-vacuum.
17. The imaging device of claim 1 , further comprising a display configured to provide a real-time view of the emitted energy.