Light emitting devices
Light-emitting devices, and related components, systems and methods are disclosed. A light-emitting device can include a multi-layer stack of materials including a light-generating region and a first layer supported by the light-generating region. During use of the light-emitting device, light generated by the light-generating region can emerge from the light-emitting device via a surface of the first layer. The light-emitting device can have an edge which is at least about one millimeter long and can be designed so that a wall plug efficiency of the light-emitting device is substantially independent of the length of the edge.
1. A light-emitting device, comprising:
a multi-layer stack of materials including a light-generating region and a first layer supported by the light-generating region so that, during use of the light-emitting device, light generated by the light-generating region can emerge from the light-emitting device via a surface of the first layer,
wherein the light-emitting device has an edge which is at least about one millimeter long, and the light-emitting device is designed so that a wall plug efficiency of the light-emitting device is substantially independent of the length of the edge; and
wherein the surface of the first layer has a dielectric function that varies spatially according to a pattern with an ideal lattice constant and a detuning parameter with a value greater than zero.
2. The light-emitting device of claim 1 , wherein the surface of the first layer has features with a size of less than about λ/5, where λ is a wavelength of light that can be generated by the light-generating region and that can emerge from the light-emitting device via the surface of the first layer.
3. The light-emitting device of claim 1 , wherein the length of the edge is at least about 1.5 millimeters.
4. The light-emitting device of claim 1 , wherein the length of the edge is at least about two millimeters.
5. The light-emitting device of claim 1 , wherein the length of the edge is at least about 2.5 millimeters.
6. The light-emitting device of claim 1 , wherein the length of the edge is at least about three millimeters.
7. The light-emitting device of claim 1 , wherein the light-emitting device includes at least one additional edge having a length of at least about one millimeter.
8. The light-emitting device of claim 1 , wherein at least about 90% of the total amount of light generated by the light-generating region that emerges from the light-emitting device emerges from the light-emitting device via the surface of the first layer.
9. The light-emitting device of claim 1 , wherein at least about 95% of the total amount of light generated by the light-generating region that emerges from the light-emitting device emerges from the light-emitting device via the surface of the first layer.
10. The light-emitting device of claim 1 , wherein the multi-layer stack of materials comprises a multi-layer stack of semiconductor materials.
11. The light-emitting device of claim 10 , wherein the first layer comprises a layer of n-doped semiconductor material, and the multi-layer stack further includes a layer of p-doped semiconductor material.
12. The light-emitting device of claim 11 , wherein the light-generating region is between the layer of n-doped semiconductor material and the layer of p-doped semiconductor material.
13. The light-emitting device of claim 1 , further comprising a support that supports the multi-layer stack of materials.
14. The light-emitting device of claim 13 , further comprising a layer of reflective material that is capable of reflecting at least about 50% of light generated by the light-generating region that impinges on the layer of reflective material, the layer of reflective material being between the support and the multi-layer stack of materials.
15. The light-emitting device of claim 14 , wherein the first layer comprises a layer of an n-doped material, the multi-layer stack of materials further includes a layer of p-doped material, and a distance between the layer of p-doped semiconductor material and the layer of reflective material is less than a distance between the layer of n-doped semiconductor material and the layer of reflective material.
16. The light-emitting device of claim 15 , further comprising a p-ohmic contact layer between the layer of p-doped material and the layer of reflective material.
17. The light-emitting device of claim 1 , further including a current-spreading layer between the first layer and the light-generating region.
18. The light-emitting device of claim 1 , wherein the multi-layer stack of materials comprise semiconductor materials.
19. The light-emitting device of claim 18 , wherein the semiconductor materials are selected from the group consisting of III-V semiconductor materials, organic semiconductor materials and silicon.
20. The light-emitting device of claim 1 , wherein the pattern does not extend into the light-generating region.
21. The light-emitting device of claim 1 , wherein the pattern does not extend beyond the first layer.
22. The light-emitting device of claim 1 , wherein the pattern extends beyond the first layer.
23. The light-emitting device of claim 1 , further comprising electrical contacts configured to inject current into the light-emitting device.
24. The light-emitting device of claim 23 , wherein the electrical contacts are configured to vertically inject electrical current into the light-emitting device.
25. The light-emitting device of claim 1 , wherein the light-emitting device is selected from the group consisting of light-emitting diodes, lasers, optical amplifiers, and combinations thereof.
26. The light-emitting device of claim 1 , wherein the light-emitting device comprises a light emitting diode.
27. The light-emitting device of claim 1 , wherein the light-emitting device is selected from the group consisting of OLEDs, flat surface-emitting LEDs, HBLEDs, and combinations thereof.
28. The light-emitting device of claim 1 , wherein the light-emitting device is in the form of a packaged light-emitting device.
29. The light-emitting device of claim 1 , wherein the light-emitting device is in the form of a packaged die.
30. A light-emitting device, comprising:
a multi-layer stack of materials including a light-generating region and a first layer supported by the light-generating region so that, during use of the light-emitting device, light generated by the light-generating region can emerge from the light-emitting device via a surface of the first layer,
wherein the light-emitting device has an edge which is at least about one millimeter long, and the light-emitting device is designed so that a wall plug efficiency of the light-emitting device is substantially independent of the length of the edge;
wherein the first layer comprises a semiconductor material and the surface of the first layer has a dielectric function that varies spatially according to a nonperiodic pattern comprising a plurality of non-concentric holes, a majority of the non-periodic pattern having order; and
wherein the light emerging from the light-emitting device via the surface of the first layer is substantially incoherent.
31. The light emitting device of claim 30 , wherein the nonperiodic pattern comprises a pattern selected from the group consisting of aperiodic patterns, Robinson patterns, and Amman patterns.
32. The light emitting device of claim 30 , wherein the nonperiodic pattern comprises a quasicrystalline pattern.
33. The light-emitting device of claim 1 , wherein the pattern comprises a plurality of holes.
34. The light-emitting device of claim 30 , wherein the holes have a cross-sectional dimension of less than 190 nanometers.
35. The light-emitting device of claim 30 , wherein the length of the edge is at least about three millimeters.
36. The light-emitting device of claim 30 , wherein at least about 90% of the total amount of light generated by the light-generating region that emerges from the light-emitting device emerges from the light-emitting device via the surface of the first layer.
37. The light-emitting device of claim 30 , wherein the multi-layer stack of materials comprises a multi-layer stack of semiconductor materials.
38. The light-emitting device of claim 30 , wherein the first layer comprises a layer of n-doped semiconductor material, and the multi-layer stack further includes a layer of p-doped semiconductor material, and the light-generating region comprises a semiconductor material.
39. The light-emitting device of claim 30 , wherein the pattern does not extend into the light-generating region.
40. The light-emitting device of claim 30 , wherein the light-emitting device comprises a light-emitting diode.
41. The light-emitting device of claim 30 , wherein the pattern is configured so that light emerging from the light-emitting device via the first surface is more collimated than a lambertian distribution of light.
42. The light-emitting device of claim 30 , wherein a majority of the holes have substantially the same size.
43. The light-emitting device of claim 30 , wherein a majority of the nearest neighbor distances between holes is substantially the same.