Systems and methods for implementing selective electromagnetic energy filtering objects and coatings using selectably transmissive energy scattering layers
A system and method are provided for forming energy filter layers or shutter components, including energy scattering layers that are actively electrically switchable. The energy filters or shutter components are operable between at least a first mode in which the layers, and thus the presentation of the shutter components, appear substantially transparent when viewed from an energy/light incident side, and a second mode in which the layers, and thus the presentation of the energy filters or shutter components, appear opaque to the incident energy impinging on the energy incident side. The differing modes are selectable by electrically energizing, differentially energizing and/or de-energizing electric fields in a vicinity of the energy scattering layers. Refractive indices of transparent particles, and the transparent matrices in which the particles are fixed, are tunable according to the applied electric fields. The energy scattering layers may conceal a sensor such as a camera or photovoltaic cell.
1. A concealable sensor, comprising:
an electromagnetic energy filtering structure for concealing a sensor, comprising:
an energy scattering layer, comprising a plurality of substantially-transparent metallic particles and a substantially-transparent matrix material that fixes the particles in a layer arrangement to form the energy scattering layer, the energy scattering layer having an energy-incident surface and an opposite surface;
a power source that generates an electrical field;
refractive indices of at least some of the plurality of substantially-transparent metallic particles fixed in the substantially-transparent matrix material being modified between a first mode and a second mode when subjected to the electrical field, via plasmon resonance;
wherein portions of the energy scattering layer are configured to allow at least one first determined wavelength of electromagnetic energy to pass through the portion of the energy scattering layer subjected to effects from the generated electrical field, and to simultaneously cause at least one second determined wavelength of electromagnetic energy to be to be scattered; and
a sensor disposed so as to receive said at least one first wavelength of electromagnetic energy impinging on said energy-incident surface and passing therethrough, after said first wavelength of electromagnetic energy has passed through said energy-incident surface;
wherein said sensor is defined as being selected from the group consisting of a camera and a photovoltaic cell.
2. The concealable sensor of claim 1 , wherein said electromagnetic energy filtering structure further comprises a plurality of transparent electrodes positioned adjacent to the other one of the energy-incident surface or the opposite surface of the energy scattering layer, the power source generating the electrical field between the transparent electrodes.
3. The concealable sensor of claim 2 , the transparent electrodes positioned on one of an energy-incident surface or the opposite surface of the energy scattering layer being formed to have a plurality of discrete electrode portions for inducing a plurality of separate electrical fields acting on the energy scattering layer, discrete portions of the energy scattering layer exhibiting different responses in the second mode.
4. The concealable sensor of claim 1 , a refractive index of at least a portion of the substantially-transparent matrix being modified by the generated electrical field between a first mode having a first refractive index and a second mode having a second refractive index.
5. The concealable sensor of claim 4 , the first refractive index rendering the energy scattering layer transparent at least in discrete portions in the first mode.
6. The concealable sensor of claim 4 ,
the particles being fixed in the matrix material in a non-homogeneous structure of the energy scattering layer,
the particles being formed of at least two separate physical or material compositions;
the non-homogeneous structure in the energy scattering layer comprising particles of a first one of the two separate physical or material compositions being fixed in the matrix material in first discrete portions and particles of a second one of the two separate physical or material compositions being fixed in the matrix in second discrete portions; and
the first discrete portions and the second discrete portions exhibiting different second refractive indices in the second mode.
7. The concealable sensor of claim 4 , the energy scattering layer in the second mode reflecting a same wavelength of incident light from the energy-incident surface in a manner that causes the energy-incident surface to appear as a single-color opaque surface.
8. The concealable sensor of claim 4 , the energy scattering layer in the second mode reflecting a first wavelength of incident light from first discrete portions of the energy-incident surface and at least one second wavelength of the incident light from one or more second discrete portions of the energy-incident surface in a manner that causes the energy-incident surface to appear as at least one of a multi-color or texturized opaque surface.