Optically hidden electromagnetic source for generation of spatially non uniform magnetic field and tunable devices made thereof
View Patent ↗An electromagnetic source has an electrode structure coupled to a substrate. The electrode structure has interspaced electrodes, at least one of which is spiral-shaped. At least one electrical contact interconnects the electrodes of the electrode structure. The electrode structure is responsive to an applied electrical current to generate a spatially non-uniform magnetic field. This field can act on a LC layer such that optical properties of the layer are controllable.
1. An electromagnetic source comprising:
a substrate;
an electrode structure coupled to said substrate, said electrode structure including interspaced electrodes, at least one of which is spiral-shaped; and
at least one electrical contact interconnecting the electrodes of said electrode structure, whereby said electrode structure is responsive to an applied electrical current to generate a spatially non-uniform magnetic field.
2. An electromagnetic source as defined in claim 1 , wherein said magnetic field is dynamically variable on a basis of said electrical current.
3. An electromagnetic source as defined in claim 1 , wherein said electromagnetic source is optically transparent.
4. An electromagnetic source as defined claim 1 , wherein said electrodes are transparent.
5. A tunable optical device for controlling the propagation of light, said optical device comprising:
a liquid crystal layer; and
an electromagnetic source adjacent said liquid crystal layer, said electromagnetic source operative to generate a spatially non-uniform magnetic field acting on said liquid crystal layer, said magnetic field being dynamically variable on a basis of electrical current applied to said electromagnetic source, such that optical properties of said device are controllable.
6. A device as defined in claim 5 , wherein said electromagnetic source includes:
a substrate;
an electrode structure coupled to said substrate, said electrode structure including interspaced electrodes, at least one of which is spiral-shaped; and
at least one electrical contact interconnecting the electrodes of said electrode structure, whereby said electrode structure is responsive to the applied electrical current to generate said spatially non-uniform magnetic field.
7. A device as defined in claim 6 , wherein said electromagnetic source is optically transparent.
8. A device as defined in claim 7 , wherein said electrodes are transparent.
9. A device as defined in claim 6 , wherein said electrodes are source electrodes, said device further comprising at least one device electrode for generating an electric field acting on said liquid crystal layer.
10. A device as defined in claim 9 , wherein said at least one device electrode is responsive to a voltage applied between itself and at least one of said source electrodes to generate said electric field.
11. A device as defined in claim 10 , wherein said device is a gradient index lens.
12. A device as defined in claim 9 , wherein said device is a gradient index lens.
13. A device as defined in claim 6 , wherein said device is a gradient index lens.
14. A device as defined in claim 5 , wherein said device is a gradient index lens.
15. A variable liquid crystal optical device for controlling the propagation of light, said optical device having its propagation of light controlled by modulation of a spatially non-uniform magnetic field.