Lighting device and method for production thereof
The invention relates to a lighting device comprising at least two light-emitting elements and a method of producing a lighting device. The light-emitting elements are connected with each other into a module via a connection element. The connection element has at least one region spaced apart from the at least two light-emitting elements. At least two modules are connected with each other in parallel. The at least one region of the connection element has a specific electrical resistance that compensate differences between electrical characteristics of at least two light-emitting elements.
1. A lighting device comprising:
at least two modules connected with each other in parallel, each of the at least two modules comprising:
a plurality of light-emitting elements comprising at least a first light-emitting element and a second light-emitting element each comprising a heat spreading element and a light-emitting diode on the heat spreading element, and
at least one connection element connecting the heat spreading element of each of the plurality of light-emitting elements of each of the at least two modules with each other, the at least one connection element having at least one region spaced apart from the plurality of light-emitting elements and having a specific electrical resistance that compensates a difference between a first forward voltage of the light-emitting diode of the first light-emitting element and a second forward voltage of the light-emitting diode of the second light-emitting element.
2. The lighting device according to claim 1 , wherein:
the plurality of light-emitting elements of each of the at least two modules are connected in series with each other, and
the specific electrical resistance of the at least one region of the at least one connection element further compensates differences between first electrical characteristics of the plurality of light-emitting elements of a first one of the at least two modules and second electrical characteristics of the plurality of light-emitting elements of a second one of the at least two modules.
3. The lighting device according to claim 1 , wherein the specific electrical resistance of the at least one region of the at least one connection element is chosen so as to affect a voltage applied to at least one of the at least two modules.
4. The lighting device according to claim 3 , wherein the specific electrical resistance of the at least one region of the at least one connection element is chosen so to affect a steepness of a current versus voltage characteristic curve of the at least one of the at least two modules.
5. The lighting device according to claim 1 , wherein:
the at least one region of the at least one connection element comprises an electrical wire, and
the specific electrical resistance of the at least one region of the at least one connection element is adapted via at least one of a length, a diameter or a material of the electrical wire.
6. The lighting device according to claim 1 , wherein:
for each of the plurality of light-emitting elements, the light-emitting diode is arranged on a first side of the heat spreading element, and
the connection element is arranged at least partially on a second side of the heat spreading element that is opposite the first side of the heat spreading element.
7. The lighting device according to claim 1 , wherein at least the plurality of light-emitting elements are encapsulated.
8. The lighting device according to claim 1 , wherein each of the at least two modules is configured to be connected to an external power supply device.
9. The lighting device according to claim 1 , wherein the plurality of light-emitting elements are arranged substantially along a longitudinal direction of the lighting device.
10. A method for producing a lighting device comprising:
providing a plurality of light-emitting elements each comprising a heat spreading element and a light-emitting diode on the heat spreading element;
choosing a plurality of connection elements with at least one region having an electrical resistance that compensates a difference between a forward voltage of a light-emitting diode of one of the plurality of light-emitting elements and a forward voltage of a light-emitting diode of another one of the plurality of light-emitting elements;
connecting the heat spreading element of at least two of the plurality of light-emitting elements in series via at least one of the plurality of connection elements to form a first module;
connecting an other at least two of the plurality of light-emitting elements in series via another at least one of the plurality of connection elements to form a second module; and
connecting the first module and the second module in parallel.
11. The method according to claim 10 , wherein the plurality of connection elements are further chosen such that the electrical resistance of the at least one region compensates binning effects between the light-emitting diodes of the first module and the second module.
12. The method according to claim 10 , wherein the plurality of connection elements are further chosen such that the electrical resistance of the at least one region compensates a voltage drop over a wire-length.
13. The method according to claim 10 , wherein, for each of the plurality of light-emitting elements, the light-emitting diode is arranged on a first side of the heat spreading element, and the connecting the at least two of the light-emitting elements in series comprises arranging the at least one region of the at least one of the plurality of connection elements on a second side of the heat spreading element of the at least two of the light-emitting elements, the second side of the heat spreading element being opposite the first side of the heat spreading element.
14. The method according to claim 10 , wherein, for each of the plurality of light-emitting elements, the light-emitting diode is arranged on a first side of the heat spreading element, and the connecting the other at least two of the light-emitting elements in series comprises arranging the at least one region of the other at least one of the plurality of connection elements on a second side of the heat spreading element of the other at least two of the light-emitting elements, the second side of the heat spreading element being opposite the first side of the heat spreading element.
15. The method according to claim 10 , wherein, for each of the plurality of light-emitting elements, the light-emitting diode is arranged on a first side of the heat spreading element, and the connecting the at least two of the light-emitting elements in series comprises arranging the at least one region of the at least one of the plurality of connection elements on the first side of the heat spreading element of the at least two of the light-emitting elements.
16. The method according to claim 10 , wherein, for each of the plurality of light-emitting elements, the light-emitting diode is arranged on a first side of the heat spreading element, and the connecting the other at least two of the light-emitting elements in series comprises arranging the at least one region of the other at least one of the plurality of connection elements on the first side of the heat spreading element of the other at least two of the light-emitting elements.
17. The method of claim 10 , wherein the plurality of connection elements are further chosen such that the electrical resistance of the at least one region compensates differences between first electrical characteristics of the plurality of light-emitting elements of the first module and second electrical characteristics of the plurality of light-emitting elements of the second module.
18. The method of claim 10 , further comprising encapsulating the plurality of light-emitting elements.
19. The method of claim 10 , further comprising arranging the plurality of light-emitting elements substantially along a longitudinal direction of the lighting device.