Solid state lighting devices having improved color uniformity and associated methods
Solid state lighting (SSL) devices and methods of manufacturing SSL devices are disclosed herein. In one embodiment, an SSL device comprises a support having a surface and a solid state emitter (SSE) at the surface of the support. The SSE can emit a first light propagating along a plurality of first vectors. The SSL device can further include a converter material over at least a portion of the SSE. The converter material can emit a second light propagating along a plurality of second vectors. Additionally, the SSL device can include a lens over the SSE and the converter material. The lens can include a plurality of diffusion features that change the direction of the first light and the second light such that the first and second lights blend together as they exit the lens. The SSL device can emit a substantially uniform color of light.
1. A solid state lighting (SSL) device, comprising:
a support having a surface and a center line axis projecting normal to the surface;
a solid state emitter (SSE) having a first side and a second side opposite the first side, the first side being at the surface of the support, and the SSE emitting a first light propagating away from the surface of the support along a plurality of first vectors;
a first lens over the SSE;
a converter material over at least a portion of the second side of the SSE, the converter material emitting a second light propagating along a plurality of second vectors; and
a dome-shaped second lens over the SSE, the first lens, and the converter material, the second lens having a plurality of diffusion features that are configured to change the direction of the first light and the second light propagating along the first and second vectors, respectively, such that the first light and the second light blend together as they exit the second lens, wherein an exterior surface of the second lens has an irregular or erratic complex curvature and the diffusion features are formed in a random pattern and wherein the diffusion features are configured at different angles relative to the SSE such that the second light propagating along the second vectors at an emission angle θ changes direction away from the center line axis and intersects with the second light propagating along the second vectors having an emission angle greater than θ and with the first light propagating along first vectors away from the center line axis.
2. The SSL device of claim 1 wherein:
the first light has a first color;
the second light has a second color different from the first color; and
the diffusion features of the second lens are configured to change the direction of the first and second vectors in at least one of a random pattern and an irregular pattern as the first and second vectors exit the second lens such that the first color and the second color blend together.
3. The SSL device of claim 1 wherein:
the second lens is sized large enough relative to the SSE such that the SSE functions effectively as a point source; and the footprint of the second lens has a generally circular shape.
4. The SSL device of claim 1 wherein the second lens includes a footprint having a shape generally similar to a shape of a footprint of the SSE at the surface of the support.
5. The SSL device of claim 1 wherein the converter material has a generally hemispherical shape.
6. The SSL device of claim 1 wherein the converter material is spaced apart from the SSE.
7. The SSL device of claim 1 wherein:
the first lens includes a footprint having a shape generally similar to a shape of a footprint of the SSE at the surface of the support, and the first lens having a conical shape.
8. The SSL device of claim 1 , wherein an exterior surface of the first lens has an irregular or erratic complex curvature.
9. The SSL device of claim 1 , wherein:
the converter material is first converter material; and
second converter material is distributed throughout the first lens or the second lens.
10. The SSL device of claim 1 , wherein:
the converter material is first converter material; and
second converter material is localized within specific regions of the first lens or the second lens.
11. The SSL device of claim 1 , wherein:
the plurality of diffusion features are further configured to change the direction of the first light and the second light propagating along the first and second vectors, respectively, such that the first light and the second light are projected toward the periphery of the SSL device.
12. A solid state lighting (SSL) device, comprising:
a support having a surface and a center line axis projecting normal to the surface;
a solid state emitter (SSE) having a first side at the surface of the support, the SSE emitting a first light along a plurality of first vectors, the first light having a first color, wherein individual first vectors each have an emission angle and propagate away from an axis that is normal to the surface of the support;
a first lens over the SSE;
a converter material over the SSE and the first lens, the converter material emitting a second light along a plurality of second vectors, the second light having a second color different from the first color, wherein individual second vectors propagate away from the converter material; and
a dome-shaped second lens over the SSE, the first lens, and the converter material, the second lens having a plurality of diffusion features that are configured to scatter the first light and the second light as they exit the second lens such that the first and second colors blend together, wherein an exterior surface of the second lens has an irregular or erratic complex curvature and the diffusion features are formed in a random pattern and wherein the diffusion features are configured at different angles relative to the SSE such that the second light propagating along the second vectors at an emission angle θ changes direction away from the center line axis and intersects with the second light propagating along the second vectors having an emission angle greater than θ and with the first light propagating along first vectors away from the center line axis.
13. The SSL device of claim 12 wherein the first color is blue, the second color is yellow, and the first and second lights diffuse to emit a substantially uniform white light across the SSL device.
14. The SSL device of claim 12 wherein:
the second lens is sized large enough relative to the SSE such that the SSE functions at least substantially as a point source; and
the second lens includes a footprint having a generally circular shape.
15. The SSL device of claim 12 wherein the second lens includes a footprint having a shape corresponding at least generally to a shape of a footprint of the SSE at the surface of the support.
16. The SSL device of claim 12 wherein the converter material is spaced apart from the SSE.
17. The SSL device of claim 12 wherein:
the first lens includes a footprint having a shape generally similar to a shape of a footprint of the SSE at the surface of the support, and the first lens having a conical shape.
18. The SSL device of claim 12 , wherein an exterior surface of the first lens has an irregular or erratic complex curvature.
19. The SSL device of claim 12 , wherein:
the converter material is first converter material; and
second converter material is distributed throughout the first lens or the second lens.
20. The SSL device of claim 12 , wherein:
the converter material is first converter material; and
second converter material is localized within specific regions of the first lens or the second lens.
21. The SSL device of claim 12 , wherein:
the plurality of diffusion features are further configured to change the direction of the first light and the second light propagating along the first and second vectors, respectively, such that the first light and the second light are projected toward the periphery of the SSL device.