Cost-effective LED lighting instrument with good light output uniformity
View Patent ↗The present disclosure involves a lighting instrument. The lighting instrument includes a board or substrate, for example, a printed circuit board. The lighting instrument also includes a plurality of light-emitting devices disposed on the substrate. The light-emitting devices may be light-emitting diode (LED) dies. The LED dies belong to a plurality of different bins. The bins are categorized based on the light output performance of the LED dies. In some embodiments, the LED dies may be binned based on the wavelength or radiant flux of the light output. The LED dies are distributed on the substrate according to a predefined pattern based on their bins. In some embodiments, the LED dies are bin-mixed in an interleaving manner.
1. An apparatus, comprising:
a substrate;
a plurality of light-emitting devices disposed on the substrate; and
a remote phosphor layer disposed over the plurality of light-emitting devices, wherein the remote phosphor layer is free of being in direct contact with the light-emitting devices;
wherein:
the light-emitting devices belong to a plurality of different bins, each bin having a corresponding light output performance; and
a distribution configuration of the light-emitting devices on the substrate conforms to a predefined pattern as a function of their respective bins.
2. The apparatus of claim 1 , wherein:
the light output performance includes performance with respect to light wavelength and performance with respect to light brightness; and
each bin corresponds to a predefined range of light wavelength or a predefined range of light brightness.
3. The apparatus of claim 1 , wherein the predefined pattern includes light-emitting devices having alternating bins.
4. The apparatus of claim 1 , wherein the predefined pattern includes a multi-dimensional distribution.
5. The apparatus of claim 1 , wherein the predefined pattern is substantially symmetrical.
6. The apparatus of claim 1 , wherein:
the plurality of light-emitting devices are configured to be driven by a plurality of different currents; and
light-emitting devices belonging to the same bin are driven by the same current.
7. The apparatus of claim 1 , wherein the remote phosphor layer has a textured surface and has diffuser particles disposed therein.
8. The apparatus of claim 7 , wherein the remote phosphor layer includes a plurality of different color phosphor components.
9. The apparatus of claim 1 , wherein the light-emitting devices each include a light-emitting diode (LED) die.
10. An apparatus, comprising:
a substrate;
a plurality of lighting-emitting diode (LED) dies located on the substrate; and
a phosphor layer disposed over the plurality of LED dies, wherein the phosphor layer has a textured surface;
wherein:
the LED dies belong to a plurality of different bins, each bin being associated with a corresponding light output performance regarding light wavelength or radiant flux; and
a distribution configuration of the LEDs on the substrate conforms to a predefined pattern as a function of their respective bins.
11. The apparatus of claim 10 , wherein the phosphor layer is remotely disposed above all of the plurality of LED dies such that none of the LED dies is in physical contact with the phosphor layer.
12. The apparatus of claim 10 , wherein the predefined pattern includes interleaving bins of LED dies.
13. The apparatus of claim 10 , wherein:
the predefined pattern is a one-dimensional pattern or a two-dimensional pattern; and
the predefined pattern is substantially symmetrical.
14. The apparatus of claim 10 , wherein the LED dies are configured to be driven by a plurality of different currents, each current driving the LED dies in a respective bin.
15. The apparatus of claim 10 , wherein:
the phosphor layer includes different color phosphor particles;
the phosphor layer includes an anti-reflective coating; and
the phosphor layer includes a plurality of diffuser particles.
16. The apparatus of claim 10 , further comprising:
a diffuser cap housing the LED dies therein; and
a heat sink thermally coupled to the LED dies through the substrate.
17. An apparatus, comprising:
a substrate;
a plurality of light-emitting devices disposed on the substrate; and
a remote phosphor layer disposed over the plurality of light-emitting devices, wherein the remote phosphor layer is free of being in direct contact with the light-emitting devices, and wherein the remote phosphor layer has a textured upper surface;
wherein:
the light-emitting devices belong to a plurality of different bins, each bin having a corresponding light output performance; and
a distribution configuration of the light-emitting devices on the substrate conforms to a predefined pattern as a function of their respective bins.
18. The apparatus of claim 17 , wherein:
the different bins include a first bin and a second bin, the first and second bins being associated with different light wavelengths or radiant fluxes;
all of the light-emitting devices in the first bin are driven by a first current; and
all of the light-emitting devices in the second bin are driven by a second current different from the first current.
19. The apparatus of claim 17 , wherein the predefined pattern is substantially symmetrical and spans in one or more dimensions.
20. The apparatus of claim 17 , wherein the remote phosphor layer contains a plurality of different types of phosphor particles, and is coated with an anti-reflective material.