Large area high-uniformity UV source with many small emitters
View Patent ↗A light-emitting source for curing applications is disclosed. The light-emitting source comprises a first housing having a top wall and one or more side walls. The top wall and the one or more side walls define a first enclosure having a first open end. The light-emitting source further comprises a plurality of light-emitting devices arranged within the first enclosure of the first housing. One side of each of the plurality of light-emitting devices faces outward from the first open end of the first enclosure. The plurality of light-emitting devices is configured to emit light from the first open end to produce a substantially uniform area of illumination on a facing portion of a surface of a target.
1. An apparatus, comprising:
a first housing having a top wall and one or more side walls, the top wall and the one or more side walls defining a first enclosure having a first open end;
a plurality of filament-less bulbs arranged within the first enclosure of the first housing, one side of each of the plurality of filament-less bulbs facing outward from the first open end of the first enclosure, the plurality of filament-less bulbs configured to emit light from the first open end to produce a substantially uniform area of illumination on a facing portion of a surface of a target,
a first reflector extending from the one or more side walls proximal to the open end of the first housing; and
a second reflector extending from the first reflector, the second reflector being separated from the first reflector by a vacuum interface window.
2. The apparatus of claim 1 , wherein a location of an individual filament-less bulbs relative to other filament-less bulbs of the plurality of filament-less bulbs is variable.
3. The apparatus of claim 1 , wherein a first location of an individual filament-less bulb is independent of a second location of other filament-less bulbs of the plurality of filament-less bulbs.
4. The apparatus of claim 1 , wherein the plurality of filament-less bulbs is arranged within the first housing with a higher density of filament-less bulbs proximal to the one or more side walls of the first housing relative to the center of the first housing.
5. The apparatus of claim 1 , wherein the plurality of filament-less bulbs is configured to emit one or more wavelengths of ultraviolet light.
6. The apparatus of claim 1 , wherein each filament-less bulb is filled with one or more materials to emit ultra-violet light in response to excitation by radio-frequency or microwave energy.
7. The apparatus of claim 1 , wherein a material filling a first filament-less bulb of the plurality of filament-less bulbs differs from a material filling a second filament-less bulb of the plurality of filament-less bulbs.
8. The apparatus of claim 1 , wherein a first filament-less bulb of the plurality of filament-less bulbs comprises:
a second housing having a second top wall and one or more second side walls, the second top wall and the one or more side walls defining a second enclosure having a second open end, a distal side of the first filament-less bulb facing outward from the second open end of the second enclosure and configured to emit light from the second open end.
9. The apparatus of claim 8 , wherein a first filament-less bulb further comprises:
a dielectric packing material thermally coupled between the second housing and a proximal side of the first filament-less bulb;
a dielectric coating formed on the backside of the first filament-less bulb;
a pair of radio-frequency or microwave electrodes extending from behind the first filament-less bulb; and
a radio frequency or microwave cable electrically coupled and extending from the pair of radio-frequency or microwave electrodes.
10. The apparatus of claim 8 , wherein the second housing is configured to receive an air or water cooled external heat sink.
11. The apparatus of claim 1 , wherein a reflective coating is included on an inner surface of the first reflector.
12. The apparatus of claim 11 , wherein the first reflector is made from one of metal or a quartz-based material.
13. The apparatus of claim 12 , wherein the quartz-based material has at least one of a high specular reflection dielectric coating or a diffuse quartz reflecting coating.
14. The apparatus of claim 11 , wherein the second reflector has the same shape as the first reflector.
15. The apparatus of claim 14 , wherein the second reflector is made from one of metal or a quartz-based material.
16. The apparatus of claim 15 , wherein the quartz-based material has at least one of a high specular reflection dielectric coating or a diffuse quartz reflecting coating.
17. The apparatus of claim 14 , further comprising a metal screen proximal the vacuum interface window.
18. The apparatus of claim 17 , wherein the vacuum interface window comprises quartz.
19. The apparatus of claim 17 , wherein the vacuum interface window comprises an anti-reflective coating on at least one surface.
20. The apparatus of claim 17 , wherein the vacuum interface window, the first reflector, and the housing form a second enclosure, the second enclosure evacuated of air to form a vacuum enclosure.