High efficiency solid-state light source and methods of use and manufacture
A high-intensity light source is formed by a micro array of a semiconductor light source such as a LEDs, laser diodes, or VCSEL placed densely on a liquid or gas cooled thermally conductive substrate. The semiconductor devices are typically attached by a joining process to electrically conductive patterns on the substrate, and driven by a microprocessor controlled power supply. An optic element is placed over the micro array to achieve improved directionality, intensity, and/or spectral purity of the output beam. The light module may be used for such processes as, for example, fluorescence, inspection and measurement, photopolymerzation, ionization, sterilization, debris removal, and other photochemical processes.
1. A lighting fixture, comprising:
a housing including at least one fluid tube arranged therein to receive coolant, flow the coolant through the housing, and flow heated coolant out of the housing;
an array of solid-state light emitters including more than two modules arranged in a line, each module having a module array of multiple light emitters on a substrate, the array of solid-state light emitters mounted in the housing, where the solid-state light emitters are configured to produce ultraviolet (UV) light, where both the fluid tube and the array of solid-state light emitters are arranged inside the housing;
a heat sink attached to the housing, the heat sink arranged to dissipate heat from the array of solid-state light emitters;
a fan arranged to blow ambient air from outside the housing across the heat sink;
a transistor-based current source electrically coupled to the array of solid-state light emitters, the current source receiving power from a power supply, the power supply providing power to each module array separately; and
drive circuitry within the housing to control operation of the solid-state light emitters.
2. The lighting fixture of claim 1 , further comprising balancing DC current between light emitters in each module array and among the module arrays.
3. The lighting fixture of claim 1 , further comprising a temperature sensor included on each module, where the temperature sensor of each module is electrically connected to a temperature sensing circuit connected to the power supply.
4. The lighting fixture of claim 1 , wherein the housing comprises a thermally conductive material and wherein the solid-state light emitters are arranged on the substrate of each module at a center-to-center spacing of less than 3 mm, where the array of solid-state light emitters includes multiple substrates including one substrate for each module.
5. The lighting fixture of claim 1 , wherein the array of solid-state light emitters includes multiple substrates including one substrate for each module and wherein the substrate of each module comprises a thermally conductive and electrically insulative substrate and wherein the solid-state light emitters are configured to produce UV light at a wavelength in a range of 100-400 nm.
6. The lighting fixture of claim 1 , wherein the array of solid-state light emitters includes multiple substrates including one substrate for each module, wherein the solid-state light emitters are arranged on the substrate with a spacing determined by a required power density of a desired operation, and wherein the housing includes plural fluid tubes to flow coolant into, through, and out of the housing, where each of the plural fluid tubes is arranged along the more than two modules inside the housing.
7. The lighting fixture of claim 1 , wherein the power supply provides a variety of power waveforms and wherein the variety of power waveforms includes waveforms at various current levels and wherein the power supply provides power to each module array separately through a plurality of first power cables, where each module array has its own first power cable connected to the power supply.
8. The lighting fixture of claim 1 , wherein the power supply provides a variety of power waveforms and wherein the variety of power waveforms includes a pulsed power waveform, the pulsed power waveform providing various current levels over time.
9. A method of radiating an object, comprising:
providing ultraviolet (UV) light through an array of solid-state light emitters including more than two modules arranged in a line, each module having a module array of multiple light emitters mounted on a substrate, the array of solid-state light emitters mounted in a housing;
powering the array of solid-state light emitters through a transistor-based current source electrically coupled to the array of solid-state light emitters, the current source receiving power from a power supply;
varying the power provided to each module array separately;
flowing coolant through a fluid tube within the housing to transfer heat from the housing and to the coolant;
controlling the flow of coolant through the fluid tube based on a sensed temperature of each module via a sensor coupled to each module; and
blowing, via a fan, air across a heat sink attached to the housing, where the heat sink is arranged to dissipate heat from the array of solid-state light emitters.
10. The method of claim 9 , wherein the varying the power includes providing continuous voltage at various current levels, and wherein the fan is connected to the heat sink.
11. The method of claim 9 , wherein the varying the power includes varying a current level using a pulsed power waveform, the pulsed power waveform providing various current levels over time and wherein flowing coolant through the fluid tube includes flowing coolant through plural fluid tubes arranged within the housing, wherein each of the plural fluid tubes is arranged along the more than two modules arranged in the line.
12. The method of claim 9 , further comprising balancing a DC current between light-emitters in each module array and among the module arrays and wherein the balancing DC current includes varying a light output intensity of the solid-state light emitters and wherein varying the power to each module array separately includes providing power to each module array separately through a plurality of power cables, where each module array has its own power cable connected to the power supply.
13. The method of claim 12 , wherein varying the light output intensity includes controlling an array light output to achieve a non-uniform light intensity and wherein providing UV light includes providing UV light at a wavelength in a range of 100-400 nm.
14. A method for sterilizing, comprising:
providing ultraviolet (UV) light through an array of solid-state light emitters including more than two modules, each module having a module array of multiple light emitters on a substrate, the array of solid-state light emitters mounted in a housing;
powering the array of solid-state light emitters through a transistor-based current source electrically coupled to the array of solid-state light emitters, the current source receiving power from a power supply;
controlling operation of the solid-state light emitters through drive circuitry;
sterilizing a material with UV light output by the array of solid-state light emitters;
cooling the housing via blowing, via a fan, air across a heat sink attached to the housing, where the fan is connected to the heat sink, and flowing coolant through a fluid tube within the housing to transfer heat from the housing and to the coolant; and
controlling the flow of coolant through the fluid tube based on a sensed temperature of each module via a sensor coupled to each module.
15. The method of claim 14 , wherein sterilizing the material includes sterilizing water with the UV light output by the array of solid-state light emitters.
16. The method of claim 14 , wherein sterilizing the material includes sterilizing blood with the UV light output by the array of solid-state light emitters.
17. The method of claim 14 , wherein sterilizing the material includes sterilizing medical devices with the UV light output by the array of solid-state light emitters.
18. The method of claim 14 , wherein sterilizing the material includes sterilizing medicines with the UV light output by the array of solid-state light emitters.
19. The method of claim 14 , wherein sterilizing the material includes sterilizing airborne particulates with the UV light output by the array of solid-state light emitters.
20. The method of claim 14 , further comprising arranging the solid-state light emitters on the substrate with a center-to-center spacing of less than 3 mm to provide a power output density for sterilizing a material and further comprising providing a power output density of 2-24 mW/cm 2 of light for sterilizing water or providing power output of UV light of a wavelength of 325-390 nm for sterilizing blood.