Optical device
There is provided a device arranged to couple with an electromagnetic source. The device comprises an optical metamaterial arranged to increase the intensity of radiation at a predetermined optical wavelength. The optical metamaterial has a periodic reflective component having a dimension no greater than the predetermined wavelength.
1. A device arranged to couple with an electromagnetic source, the device comprising an optical metamaterial arranged to increase the intensity of radiation at a predetermined optical wavelength, the optical metamaterial having a periodic reflective component having a dimension no greater than the predetermined wavelength; wherein the optical metamaterial further comprises a fluorescent material to convert radiation at the predetermined optical wavelength to a further optical wavelength.
2. A device as claimed in claim 1 wherein the periodic reflective component comprises a regular array of reflective elements, wherein each reflective element has a first dimension no greater than the predetermined optical wavelength.
3. A device as claimed in claim 1 wherein the periodic reflective component comprises a regular grid having a periodicity in one dimension no greater than the predetermined optical wavelength.
4. A device as claimed in claim 1 wherein the periodic reflective component is supported by a dielectric.
5. A device as claimed in claim 1 further comprising a reflector.
6. A device as claimed in claim 5 wherein the reflector is a second optical metamaterial having a periodic reflective component.
7. A device as claimed in claim 5 wherein the optical metamaterial and reflector are respectively arranged to form an open or closed cavity arranged to receive an electromagnetic source.
8. A device as claimed in claim 5 wherein the cavity is arranged to emit radiation at the predetermined optical wavelength at a predetermined angle, θ, to the optical metamaterial.
9. A device as claimed in claim 8 wherein the optical metamaterial and reflector are spatially separated by a distance, S, defined by the equation:
S
=
(
φ
(
θ
)
π
-
1
)
λ
0
4
+
m
λ
0
2
,
where φ(θ) is the reflection coefficient phase at the predetermined angle, λ 0 is the predetermined wavelength and m is an integer.
10. A device as claimed in claim 1 further comprising a further optical metamaterial layered with the first optical metamaterial, the further optical metamaterial having a periodic reflective component arranged to increase the intensity of radiation, from the electromagnetic source, at a second predetermined optical wavelength.
11. A radiation emitting device comprising:
a cavity at least partially delimited by an optical metamaterial and a reflector;
an electromagnetic source within the cavity; and wherein the optical metamaterial comprises a periodic reflective component arranged to receive radiation from the electromagnetic source and increase the intensity of radiation at a predetermined optical wavelength;
wherein the optical metamaterial further comprises a fluorescent material to convert radiation at the predetermined optical wavelength to a further optical wavelength.
12. A radiation emitting device as claimed in claim 11 wherein the periodic reflective component comprises: a regular array of reflective elements, wherein each reflective element has a first dimension no greater than the predetermined optical wavelength; or a regular grid having a periodicity in one dimension no greater than the predetermined optical wavelength.
13. A radiation emitting device as claimed in claim 11 wherein the cavity is planar, at least partially spherical, hemispherical or at least partially cylindrical.
14. A radiation emitting device as claimed in claim 11 wherein the device is arranged to emit light at the predetermined optical wavelength at a predetermined angle to the optical metamaterial.
15. An array of radiation emitting devices as claimed in claim 11 wherein the light emitting devices are arranged in a planar array or cylindrical array.
16. A device as claimed in claim 1 wherein the electromagnetic source is at least one selected from the group comprising: an incandescent lamp; a light-emitting diode; a compact fluorescent lamp; and a laser.
17. A device as claimed in claim 11 wherein the electromagnetic source is at least one selected from the group comprising: an incandescent lamp; a light-emitting diode; a compact fluorescent lamp; and a laser.
18. A device as claimed in claim 1 wherein the fluorescent material comprises phosphor.
19. A device as claimed in claim 1 wherein the fluorescent material converts radiation at the predetermined optical wavelength to a visible wavelength.
20. A device arranged to couple with an electromagnetic source, the device comprising an optical metamaterial arranged to increase the intensity of radiation at a predetermined optical wavelength, the optical metamaterial having a periodic reflective component having a dimension no greater than the predetermined wavelength, and a reflector, wherein the reflector is a second optical metamaterial having a periodic reflective component.
21. A device as claimed in claim 20 wherein the periodic reflective component comprises a regular array of reflective elements, wherein each reflective element has a first dimension no greater than the predetermined optical wavelength.
22. A device as claimed in claim 20 wherein the periodic reflective component comprises a regular grid having a periodicity in one dimension no greater than the predetermined optical wavelength.
23. A device as claimed in claim 20 wherein the periodic reflective component is supported by a dielectric.
24. A device as claimed in claim 20 wherein the optical metamaterial and reflector are respectively arranged to form an open or closed cavity arranged to receive an electromagnetic source.
25. A device as claimed in claim 20 wherein the cavity is arranged to emit radiation at the predetermined optical wavelength at a predetermined angle, θ, to the optical metamaterial.
26. A device as claimed in claim 25 wherein the optical metamaterial and reflector are spatially separated by a distance, S, defined by the equation:
S
=
(
φ
(
θ
)
π
-
1
)
λ
0
4
+
m
λ
0
2
,
where φ(θ) is the reflection coefficient phase at the predetermined angle, λ 0 is the predetermined wavelength and m is an integer.
27. A device as claimed in claim 20 further comprising a further optical metamaterial layered with the first optical metamaterial, the further optical metamaterial having a periodic reflective component arranged to increase the intensity of radiation, from the electromagnetic source, at a second predetermined optical wavelength.
28. A device as claimed in claim 20 wherein the electromagnetic source is at least one selected from the group comprising: an incandescent lamp; a light-emitting diode; a compact fluorescent lamp; and a laser.
29. A device arranged to couple with an electromagnetic source, the device comprising an optical metamaterial arranged to increase the intensity of radiation at a predetermined optical wavelength, the optical metamaterial having a periodic reflective component having a dimension no greater than the predetermined wavelength, and a reflector;
wherein the optical metamaterial and reflector are respectively arranged to form an open or closed cavity arranged to receive an electromagnetic source, the cavity is arranged to emit radiation at the predetermined optical wavelength at a predetermined angle, θ, to the optical metamaterial;
wherein the optical metamaterial and reflector are spatially separated by a distance, S, defined by the equation:
S
=
(
φ
(
θ
)
π
-
1
)
λ
0
4
+
m
λ
0
2
,
where φ(θ) is the reflection coefficient phase at the predetermined angle, λ 0 is the predetermined wavelength and m is an integer.
30. A device as claimed in claim 29 wherein the periodic reflective component comprises a regular array of reflective elements, wherein each reflective element has a first dimension no greater than the predetermined optical wavelength.
31. A device as claimed in claim 29 wherein the periodic reflective component comprises a regular grid having a periodicity in one dimension no greater than the predetermined optical wavelength.
32. A device as claimed in claim 29 wherein the periodic reflective component is supported by a dielectric.
33. A device as claimed in claim 29 further comprising a further optical metamaterial layered with the first optical metamaterial, the further optical metamaterial having a periodic reflective component arranged to increase the intensity of radiation, from the electromagnetic source, at a second predetermined optical wavelength.
34. A device as claimed in claim 29 wherein the electromagnetic source is at least one selected from the group comprising: an incandescent lamp; a light-emitting diode; a compact fluorescent lamp; and a laser.
35. A device arranged to couple with an electromagnetic source, the device comprising an optical metamaterial arranged to increase the intensity of radiation at a predetermined optical wavelength, the optical metamaterial having a periodic reflective component having a dimension no greater than the predetermined wavelength; further comprising a further optical metamaterial layered with the first optical metamaterial, the further optical metamaterial having a periodic reflective component arranged to increase the intensity of radiation, from the electromagnetic source, at a second predetermined optical wavelength.
36. A device as claimed in claim 35 wherein the periodic reflective component comprises a regular array of reflective elements, wherein each reflective element has a first dimension no greater than the predetermined optical wavelength.
37. A device as claimed in claim 35 wherein the periodic reflective component comprises a regular grid having a periodicity in one dimension no greater than the predetermined optical wavelength.
38. A device as claimed in claim 35 wherein the periodic reflective component is supported by a dielectric.
39. A device as claimed in claim 35 further comprising a reflector.
40. A device as claimed in claim 39 wherein the optical metamaterial and reflector are respectively arranged to form an open or closed cavity arranged to receive an electromagnetic source.
41. A device as claimed in claim 35 wherein the electromagnetic source is at least one selected from the group comprising: an incandescent lamp; a light-emitting diode; a compact fluorescent lamp; and a laser.