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 method of manufacturing a solid state lighting (SSL) device, comprising:
positioning a solid state emitter (SSE) on a surface of a support, the support having a centerline axis projecting normal to the surface;
wherein the solid state emitter has a first side and a second side opposite the second side, the first being at the surface of the support;
positioning a first lens over the SSE;
covering at least a portion of the second side of the SSE a with a converter material; and
positioning a dome-shaped second lens over the SSE, the first lens, and the converter material, the second lens having a plurality of diffusion features,
wherein, in operation, the SSE emits a first light propagating away from the surface of the support along a plurality of first vectors, the converter material emits a second light propagating along a plurality of second vectors, and wherein the plurality of diffusion features 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 propagating 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 the first vectors away from the center line axis.
2. The method of claim 1 wherein positioning the second lens comprises at least one of injection molding and overmolding the second lens over the SSE, the first lens, and the converter material.
3. The method of claim 1 wherein positioning the second lens comprises:
forming the second lens separately from the SSE; and
attaching the second lens on the surface of the support after the second lens is formed.
4. The method of claim 1 wherein positioning the second lens comprises:
sizing the second lens large enough relative to the SSE such that the SSE functions effectively as a point source; and
forming a base portion of the second lens, the base portion being proximate to the surface of the support, wherein the base portion has a generally circular shape.
5. The method of claim 1 wherein positioning the second lens comprises:
forming a base portion of the second lens, the base portion being proximate to the surface of the support, wherein the base portion has a shape at least generally corresponding to a shape of the SSE at the surface of the support.