High efficiency LEDs and LED lamps
View Patent ↗In various embodiments, lighting systems include a carrier having a plurality of conductive elements disposed thereon and a light-emitting array. The light-emitting array is disposed over the carrier and includes a plurality of light-emitting diodes (LEDs), each of which has at least two electrical contacts electrically connected to conductive elements.
1. A lighting system comprising:
a thermally conductive carrier having a plurality of conductive elements disposed thereover;
disposed over the carrier, a light-emitting array comprising a plurality of electrically connected unpackaged light-emitting diodes (LEDs), each unpackaged LED having at least two electrical contacts, wherein at least some of the electrical contacts are each electrically connected to a conductive element; and
a light-conversion material disposed over the unpackaged LEDs for absorption of at least a portion of light emitted from the unpackaged LEDs and emission of converted light having a different wavelength, converted light and unconverted light emitted by the light-emitting elements combining to form mixed light.
2. The system of claim 1 , wherein at least one unpackaged LED has (i) one electrical contact electrically coupled to a first conductive element with a wire bond and (ii) another electrical contact electrically coupled to a second conductive element with at least one of solder or conductive adhesive.
3. The system of claim 1 , wherein at least one unpackaged LED has (i) one electrical contact electrically coupled to an electrical contact of a first different unpackaged LED and (ii) another electrical contact electrically coupled to an electrical contact of a second different unpackaged LED.
4. The system of claim 1 , wherein at least one unpackaged LED has (i) one electrical contact electrically coupled to a first conductive element with a wire bond and (ii) another electrical contact electrically coupled to a second conductive element with a wire bond.
5. The system of claim 1 , wherein at least one unpackaged LED has (i) one electrical contact electrically coupled to a conductive element and (ii) another electrical contact electrically coupled to an electrical contact of a different unpackaged LED.
6. The system of claim 1 , wherein at least one electrical contact of at least one of the unpackaged LEDs is electrically coupled to a conductive element with at least one of solder or conductive adhesive.
7. The system of claim 1 , further comprising at least two connection points, disposed on the carrier, for facilitating electrical connection to the plurality of unpackaged LEDs.
8. The system of claim 1 , wherein at least one electrical contact of at least one of the unpackaged LEDs is electrically coupled to a conductive element with a wire bond.
9. The system of claim 1 , wherein at least some of the unpackaged LEDs are electrically connected in a combination of series and parallel configurations.
10. The system of claim 1 , further comprising at least one optical element configured for at least one of focusing or shaping the mixed light to a desired illumination pattern.
11. The system of claim 1 , wherein the carrier comprises at least one of silicon, aluminum nitride, silicon carbide, diamond, sapphire, aluminum, or copper.
12. The system of claim 1 , further comprising an electrically insulating layer between the thermally conductive carrier and the conductive elements.
13. The system of claim 1 , wherein the carrier is reflective to a wavelength of converted light emitted by the light-conversion material.
14. The system of claim 1 , wherein all of the unpackaged LEDs have substantially the same emission wavelength.
15. The system of claim 1 , wherein at least some of the unpackaged LEDs are electrically connected in parallel.
16. The system of claim 1 , wherein the unpackaged LEDs are attached to the substrate with an adhesive or solder.
17. The system of claim 1 , wherein at least some of the unpackaged LEDs are electrically connected in series.
18. The system of claim 1 , wherein the carrier is reflective to a wavelength of light emitted by the LEDs.
19. The system of claim 1 , wherein the carrier is reflective to a wavelength of the mixed light.
20. The system of claim 1 , wherein the mixed light is substantially white light.
21. The system of claim 1 , wherein the carrier defines a plurality of depressions, and each unpackaged LED is disposed within a depression.
22. The system of claim 21 , wherein each depression is reflective to a wavelength of converted light emitted by the light-conversion material.
23. The system of claim 21 , wherein each depression is reflective to a wavelength of light emitted by the unpackaged LEDs.
24. The system of claim 21 , wherein each depression is reflective to a wavelength of the mixed light.