Isotropic collimation devices and related methods
Devices, such as light-emitting devices (e.g., LEDs), and methods associated with such devices are provided. A light-emitting device may include an interface through which emitted light passes therethrough. The interface having a dielectric function that varies spatially according to a pattern, wherein the pattern is arranged to provide light emission that has a substantially isotropic emission pattern and is more collimated than a Lambertian distribution of light.
1. A light-emitting device comprising:
an interface through which emitted light passes therethrough, the interface having a dielectric function that varies spatially according to a pattern, the pattern arranged to provide light emission that has a substantially isotropic emission pattern and is more collimated than a Lambertian distribution of light, wherein the substantially isotropic emission pattern is such that an integrated intensity varies by less than 20% over all azimuthal angles, wherein the integrated intensity is a summed intensity over all polar collection angles.
2. The device of claim 1 , wherein the integrated intensity varies by less than 10% over all azimuthal angles.
3. The device of claim 1 , wherein a total of the emitted light within a solid angle collection cone is greater than a total emission corresponding to the Lambertian distribution within the solid angle collection cone, wherein the solid angle collection cone has a center axis oriented along a normal of the surface.
4. The device of claim 3 , wherein the solid angle collection cone has a collection angle of 30 degrees with respect to the normal of the surface.
5. The device of claim 1 , wherein the pattern conforms to a transformation of a precursor pattern according to a mathematical function.
6. The device of claim 5 , wherein the precursor pattern comprises a periodic pattern.
7. The device of claim 6 , wherein the precursor pattern comprises a hexagonal pattern.
8. The device of claim 5 , wherein the precursor pattern comprises a non-periodic pattern.
9. The device of claim 5 , wherein the mathematical function comprises providing an angular displacement that at least depends on a radial distance from a reference origin.
10. The device of claim 5 , wherein the precursor pattern comprises a plurality of features, and wherein the transformation of a precursor pattern is applied to positions of the plurality of features of the precursor pattern.
11. The device of claim 1 , wherein the pattern comprises a plurality of holes formed in the interface.
12. The device of claim 1 , wherein the pattern is non-periodic.
13. The device of claim 1 , wherein the pattern comprises a first region and a second region, the first region having a dielectric function that varies spatially according to a first pattern, the second region having a dielectric function that varies spatially according to a second pattern, the second pattern being a rotation of the first pattern.
14. The device of claim 13 , wherein the first region has an area of greater than 100 microns 2 .
15. The device of claim 13 , wherein the first region has an area of less than 40000 microns 2 .
16. The device of claim 13 , wherein the first pattern is periodic.
17. The device of claim 16 , wherein the first pattern comprises a hexagonal pattern.
18. The device of claim 13 , wherein the first pattern is non-periodic.
19. The device of claim 13 , wherein the first pattern is quasi-crystalline.