Lens arrangements for light-emitting diode packages
Solid-state lighting devices including light-emitting diodes (LEDs) and lens arrangements for packaged LED devices are disclosed. An LED package may include one or more LED chips on a submount with a lens positioned on the submount to form a cavity. The one or more LED chips may reside in the cavity without direct encapsulation materials that would otherwise contact the one or more LED chips and any corresponding wirebonds. In this manner, the one or more LED chips may be driven with higher drive currents while reducing degradation and mechanical strain effects related to differences in coefficients of thermal expansion with typical encapsulant materials. LED packages may also be configured with one or more apertures that allow air flow between an interior volume of a cavity and an ambient environment outside the LED package to promote heat dissipation at higher drive currents.
1. A light-emitting diode (LED) package comprising:
a submount;
at least one LED chip on the submount;
at least one spacer on the submount; and
a lens on the at least one spacer such that the at least one spacer is between the lens and the at least one LED chip and a cavity is at least partially formed between the lens and the submount, the cavity being registered with the at least one LED chip and configured to allow air flow between an interior volume of the cavity and an ambient environment outside the LED package during operation of the at least one LED chip.
2. The LED package of claim 1 , wherein the at least one spacer comprises a plurality of spacers between the lens and the submount.
3. The LED package of claim 1 , wherein the at least one spacer forms a height from the submount that is greater than a height of the at least one LED chip.
4. The LED package of claim 1 , wherein the at least one spacer forms at least one aperture that is arranged to allow the air flow from outside the LED package.
5. The LED package of claim 1 , wherein the at least one spacer forms a plurality of apertures arranged to allow the air flow from outside the LED package.
6. The LED package of claim 1 , wherein the at least one spacer forms a first aperture at a first peripheral edge of the lens and a second aperture at a second peripheral edge of the lens.
7. The LED package of claim 1 , wherein the at least one spacer is arranged along a perimeter of the lens.
8. The LED package of claim 7 , wherein the lens is at least partially embedded within the at least one spacer along the perimeter of the lens.
9. The LED package of claim 7 , wherein the at least one spacer comprises silicone.
10. The LED package of claim 7 , wherein the lens is attached to the at least one spacer with an adhesive material.
11. The LED package of claim 7 , wherein the lens forms a rectangular shape and the at least one spacer is arranged at one or more corners of the lens.
12. The LED package of claim 7 , wherein the lens forms a rectangular shape and the at least one spacer is arranged along one or more side edges of the lens.
13. The LED package of claim 1 , wherein the submount comprises a plurality of electrical traces that are electrically coupled to the at least one LED chip.
14. The LED package of claim 13 , wherein the at least one LED chip is electrically coupled to a first electrical trace of the plurality of electrical traces by at least one wire bond, the at least one wire bond being arranged within the cavity.
15. The LED package of claim 13 , wherein the at least one spacer is arranged to at least partially cover the plurality of electrical traces.
16. A light-emitting diode (LED) package comprising:
a submount comprising a first face and a second face that opposes the first face;
at least one LED chip on the first face; and
a lens attached to portions of the first face that laterally surround the at least one LED chip such that a cavity is at least partially formed between the lens and the submount, the cavity configured to allow air flow between an interior volume of the cavity and an ambient environment outside the LED package, the air flow being defined in at least two directions from the at least one LED chip during operation of the at least one LED chip, and the at least two directions being defined between the first face and the lens.
17. The LED package of claim 16 , wherein the lens forms at least one aperture that is arranged to allow the air flow from outside the LED package.
18. The LED package of claim 16 , wherein the lens forms a plurality of apertures arranged to allow the air flow from outside the LED package.
19. The LED package of claim 16 , wherein the lens comprises lens portions that extend below a horizontal plane defined by a top surface of the at least one LED chip.
20. The LED package of claim 19 , wherein the lens portions are adhered to the submount by an adhesive.
21. The LED package of claim 19 , wherein the lens forms a rectangular shape and the lens portions are arranged at one or more corners of the lens.
22. The LED package of claim 19 , wherein the lens forms a rectangular shape and the lens portions are arranged along one or more side edges of the lens.
23. The LED package of claim 16 , wherein the submount comprises a plurality of electrical traces that are electrically coupled to the at least one LED chip.
24. The LED package of claim 23 , wherein the at least one LED chip is electrically coupled to a first electrical trace of the plurality of electrical traces by at least one wire bond, the at least one wire bond being arranged within the cavity.