Ultraviolet systems and methods for irradiating a substrate

Abstract

To provide a UV system and a method to improve fields such as power efficiency, output, versatility, and lives of components.SOLUTION: A UV system (10) for irradiating a substrate (26) includes a lamphead (16) having an enclosure with an interior. A UV bulb (24) is positioned in the interior and is capable of emitting UV energy when excited by RF energy. The UV system (10) also includes a solid state RF source (12) capable of generating the RF energy. The RF energy is transmitted to the UV bulb (24), which causes the UV bulb (24) to ignite and emit the UV energy from the interior of the lamphead (16).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to ultraviolet (hereinafter "UV") systems for irradiating substrates, and in particular to the construction and interaction of radio frequency (hereinafter "RF") energy sources and UV bulbs used in such systems. [Background technology]

[0002] A conventional UV system includes one or more magnetrons and a UV bulb. Upon application of power, the magnetron generates RF energy, which is transmitted to the UV bulb via a waveguide, causing the gas in the UV bulb to ignite and turn into a plasma state. As a result of this excitation, the UV bulb begins to emit UV energy, which is then utilized for various applications. For example, the UV energy may irradiate a substrate to cure a material thereon or for other purposes, such as surface treatment. For example, a material, such as an ink or adhesive, may be cured on a substrate by directing radiated UV energy onto the substrate. As another example, the UV energy may be directed to a substrate to modify its surface.

[0003] In such conventional UV systems, a high power magnetron is required to provide sufficient RF energy to drive the gas in the UV bulb into a plasma state. One or more magnetrons are typically included in a lamphead having a UV bulb. When more than one magnetron is used, the frequencies of the RF energy generated by the magnetrons must be far enough apart so that one magnetron does not damage or interfere with the other, but at the same time, sufficient to fully excite the UV bulb. As a result, implementing multiple magnetrons, especially three or more magnetrons, in one lamphead causes operational problems and reduces efficiency. This is because a wider range of RF frequencies is required when multiple magnetrons are used. Some frequencies within that range reduce efficiency in exciting the UV bulb.

[0004] In a conventional lamphead, the UV bulb is mounted in a metal microwave cavity or chamber and positioned at the focal point of a parabolic reflector. In operation, RF energy generated by a magnetron passes through a waveguide into the microwave cavity or chamber, which ignites the attached UV bulb, emitting UV energy as described above. To be effective, such a conventional lamphead configuration requires precise cooling of the lamphead to adequately remove the heat generated by the magnetron and provide proper distribution of cooling air throughout the entire length of the UV bulb. The cooling must be precise because overcooling of the magnetron or UV bulb can cause permanent damage to these components, and overcooling of the UV bulb can adversely affect the UV output and even cause the bulb to depreciate, thereby separating the bulb gases and thus inhibiting the bulb from restarting. Due to the volume of air required to adequately cool both the magnetron and the UV bulb, conventional UV lampheads typically have an air blower and a specifically designed plenum. Due to factors such as cooling and bulb start-up, tapered UV bulbs are utilized that have a narrower diameter in the center region than in the end regions. Such special bulb shapes help ensure balanced operation of the magnetron cooling without overcooling the UV bulb. However, such shapes increase the complexity and cost of manufacturing the UV bulb.

[0005] The lamphead configurations used in conventional UV systems have additional problems. For example, the use of magnetrons and their containment in the lamphead with the UV bulbs causes the overall system to have a power efficiency of about 70-80% due to the unstable RF output characteristic of the magnetrons and the cooling requirements mentioned above. Such lamphead configurations also cause an increase in the required size and weight of the lamphead. Furthermore, because magnetrons are slow to start and shut down, conventional UV systems often have a starter bulb in the lamphead. The starter bulb is powered at the same time that the magnetron is initially energized, helping the UV bulb to ignite more quickly, thereby allowing conventional UV systems to begin generating UV energy more quickly. The starter bulb also increases the size and power consumption of the lamphead.

[0006] Also, to generate maximum UV energy from a UV bulb, it is necessary to distribute the RF energy evenly along the entire length of the bulb. Furthermore, the intensity of the emitted UV energy is highly dependent on the RF energy applied to the UV bulb. Although waveguides used in conventional UV systems help distribute the RF energy generated by a magnetron along the entire length of the bulb, such waveguides have a fixed geometry and require a standing wavelength that is directly proportional to the output frequency of the magnetron. Magnetrons do not provide a stable or finely tunable RF output frequency, which can result in poor RF energy coupling and non-uniform illumination of the UV bulb.

[0007] Magnetrons also have a limited lifespan due to degradation of the filament over time. When utilized as part of a conventional UV system, the lifespan of a magnetron can be as short as 1000 hours. The limited lifespan of magnetrons is a concern because the downtime required to replace end-of-life magnetrons can be expensive. As a result, aggressive maintenance schedules are often implemented to replace magnetrons before they fail, further increasing costs. Summary of the Invention [Problem to be solved by the invention]

[0008] For these reasons, as well as others, it would be desirable to provide UV systems and methods that improve areas such as power efficiency, output, versatility, and component life. [Means for solving the problem]

[0009] Generally, the present invention provides a UV system for irradiating a substrate. The UV system includes a lamphead having an interior and a solid-state RF source capable of generating RF energy. A UV bulb is positioned within the interior of the lamphead and capable of emitting UV energy when excited by RF energy generated by the solid-state RF source. In one illustrated embodiment, the solid-state RF source is positioned outside the interior of the lamphead. Alternatively, the solid-state RF source is positioned inside the interior of the lamphead.

[0010] Various additional features are included in embodiments of the invention. For example, a cooling device is positioned inside or outside the interior of the lamphead to direct cooling air to the UV bulb. An RF transmitter is coupled to the solid-state RF source and capable of receiving RF energy from the solid-state RF source and directing the RF energy toward the UV bulb. In some embodiments, the RF transmitter further comprises at least one antenna positioned proximate to the UV bulb. In the illustrated embodiment, multiple antennas are utilized and spaced along the length of the UV bulb. When the solid-state RF source is positioned inside the interior of the lamphead, the RF transmitter may comprise a waveguide.

[0011] In another embodiment, the system includes a controller for sending at least one control signal to the solid-state RF source, the control signal defining a frequency of RF energy generated by the solid-state RF source. In yet another embodiment, at least one additional solid-state RF source is provided and capable of generating RF energy directed to the UV bulb. In these embodiments, the controller sends at least one control signal to each of the plurality of solid-state RF sources, respectively. Each control signal defines a frequency of RF energy generated by each solid-state RF source.

[0012] The invention also generally provides a method of irradiating a substrate with UV energy. The method includes generating RF energy with a solid-state RF source and transmitting the generated RF energy to a UV bulb in a lamphead. The UV bulb is ignited with the generated RF energy and UV energy is generated from the ignited UV bulb. A substrate is irradiated with the UV energy by directing the UV energy outside the lamphead to the substrate. In various embodiments, the method further includes generating a first data signal and receiving the first data signal at a solid-state RF source that defines a first desired frequency for the generated RF energy. Generating the RF energy at the solid-state RF source may include generating RF energy having the first desired frequency at the solid-state RF source and igniting the UV bulb with the generated additional RF energy. The method may further include generating a second data signal and receiving the second data signal at a second solid-state RF source that defines a second desired frequency equal to the first desired frequency. Additional RF energy is generated by the second solid-state RF source having the second desired frequency, the additional RF energy is transmitted to the UV bulb, and the UV bulb is ignited with the generated additional RF energy.

[0013] Various additional features and advantages of the present invention will become more apparent to those skilled in the art from the following detailed description of the illustrative embodiments, which should be considered in conjunction with the accompanying drawings. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram of a UV irradiation system including a solid-state RF source positioned outside the lamphead and a cooling device positioned inside the lamphead.

[0015] [Diagram 2] FIG. 2 is a schematic diagram of a UV irradiation system including a solid-state RF source and a cooling device positioned outside the lamphead.

[0016] [Diagram 3] FIG. 3 is a schematic diagram of a solid-state RF source.

[0017] [Figure 4] FIG. 4 is a schematic diagram of a UV irradiation system including a solid state RF source and a cooling device positioned inside the lamphead.

[0018] [Diagram 5] FIG. 5 is a schematic diagram of a UV irradiation system including a solid state RF source positioned inside the lamphead and a cooling device positioned outside the lamphead.

[0019] [Figure 6] FIG. 6 is a flow chart illustrating the sequence of actions performed during a UV exposure process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The accompanying drawings, which are not necessarily to scale, provide somewhat simplified views of various features illustrating the underlying principles of the present invention. The specific design features of the sequences of operations as described herein, including, for example, the specific dimensions, orientations, positions, and shapes of the various illustrated elements, will be determined in part by the particular intended application and environment of use. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration purposes.

[0021] 1 is a schematic diagram of an exemplary UV system 10 for irradiating a substrate. The UV system 10 includes one or more solid state RF sources capable of generating RF energy. As an example, a suitable solid state RF source 12 may be Panasonic part number SSMM-200-A01. In some embodiments, the solid state RF source 12 includes multiple solid state RF generators connected together using a combiner. In some embodiments, the solid state RF source 12 is mounted within a Faraday cage 14.

[0022] The UV system 10 also includes a lamphead 16 having an interior. The solid state RF source 12 is located outside the interior of the lamphead 16 and is coupled by one or more cables 20 to one or more antennas 18 positioned inside the interior of the lamphead 16. Preferably, the multiple antennas are located inside the interior of the lamphead 16. The cables 20 may include any type of propagation medium suitable for carrying RF energy generated by the solid state RF source 12 to the antennas 18, such as at least one concentric cable. In some embodiments, each of the cables is connected at or near the solid state RF source 12 to a multi-line cable carrying the multiple cables 20. Upon entering or within the interior of the lamphead, the cables 20 may be separated from the multi-line cable to each of the antennas 18 inside the interior of the lamphead 16, thereby reducing clutter from running multiple separate cables 20 to the lamphead 16. In some embodiments, each solid state RF source 12 is coupled to a single antenna 18. Alternatively, the solid state RF source 12 may be coupled to multiple antennas using splitters.

[0023] The UV system 10 also includes a UV bulb 24 positioned within the lamphead 16 and capable of emitting UV energy. Generally, the UV bulb 24 is elongated and contains a gas mixture that, when excited by RF energy generated by the solid-state RF source 12, becomes a plasma state. The excitation of the gas ignites the UV bulb 24, causing UV energy to be emitted from within the lamphead 16. The UV energy can be directed toward a substrate 26, for example, to modify the surface of the substrate or cure a material on the substrate. The substrate 26 can be any surface suitable for receiving UV energy during the irradiation process. Non-limiting examples include plastic, metal, silicon, leather, fiber, composites, glass, etc. The UV bulb 24 can be of any type suitable for generating UV energy when RF energy is introduced thereto, such as a mercury-filled quartz bulb with or without iron, gallium, indium, lead, and / or other gas additives.

[0024] One or more antennas 18 are positioned in close proximity to the UV bulb 24. This means that the antenna 18 is in a position such that an RF signal transmitted from the antenna 18 can reach and effectively excite the UV bulb 24. For this purpose, the antenna 18 can be any device capable of receiving RF energy from the solid-state RF source 12 and directing the RF energy toward the UV bulb 24. In one embodiment, RF energy generated by the solid-state RF source 12 is transmitted to the antenna 18 via a cable 20. The antenna 18 distributes the RF energy along the length of the UV bulb 24.

[0025] In general, the placement of the antennas 18 may provide uniform heating along the UV bulb 24. In some embodiments, each antenna 18 is a circular antenna optimized for a radiation frequency or range of radiation frequencies. Additionally and / or alternatively, each antenna may be positioned along the length of the bulb 24 with no or minimal overlap between the RF energy transmitted from each of the antennas 18. Furthermore, the RF energy signal emitted from each antenna 18 may have the highest energy density at the center of the signal.

[0026] In one embodiment, each of the antennas 18 is positioned at an equal distance from the surface of the UV bulb 24, for example, about ½ inch from the surface of the UV bulb 24. Additionally and / or alternatively, each of the antennas 18 may be equally spaced along the surface of the UV bulb 24. In one exemplary embodiment, when a 6 inch UV bulb and three 1000 watt fixed RF sources 12 are implemented in the UV system 10, the antennas 18 may be positioned every 1.5 inches to 2 inches along the surface of the UV bulb 24 (e.g., three antennas positioned along the surface of the UV bulb 24). In another example, when a 3 inch UV bulb is implemented in the UV system 10, two antennas 18 may be positioned along the surface of the UV bulb 24. In another embodiment, one antenna may be used for the smaller UV bulb 24.

[0027] Unlike magnetrons used in conventional UV systems, the solid-state RF sources 12 are designed to suppress the RF energy generated by one solid-state RF source from affecting another, regardless of the frequency of the RF signal. Thus, operational concerns regarding RF frequency when utilizing multiple magnetrons are not present in the UV system 10. Thus, each of the solid-state RF sources 12 can generate RF energy of the same or nearly the same frequency during the irradiation process, which further results in more uniform and efficient heating of the UV bulbs 24.

[0028] Furthermore, due to the longer operational life of the solid-state RF source 12 as compared to a magnetron, the UV system 10 can operate for a longer period of time without the need for repair or replacement of parts, resulting in reduced costs associated with maintaining and replacing parts.

[0029] The UV system 10 also includes a cooling device 28. Generally, the cooling device 28 can prevent the contents of the lamphead 16, such as the UV bulb 24, from overheating during operation of the UV system 10. In some embodiments, the cooling device 28 is positioned internal to the lamphead 16. Additionally and / or alternatively, the cooling device 28 can be positioned external to the lamphead 16 (e.g., FIG. 2).

[0030] Unlike conventional UV systems, less air is required to adequately cool the lamphead 16 of the UV system 10 because there is no RF source within the lamphead 16 to generate heat. Therefore, instead of an air blower, the cooling device 28 may include one or more air knives and / or nozzles capable of cooling the contents of the lamphead 16. The air knives and nozzles each provide more precise and effective cooling when the volume of cooling required is smaller compared to an air blower. The air knives can generate a sheet of air to cool the contents of the lamphead 16, such as the UV bulb 24, during the irradiation process. The nozzles can generate a jet of air to cool the contents of the lamphead 16 during the irradiation process. The sheet of air and / or the jet of air can be uniform, laminar, non-uniform, and / or turbulent. Furthermore, the jet of air and / or the sheet of air can be formed from compressed air and / or cooling air. In an exemplary embodiment, the compressed air and / or cooling air includes an inert gas.

[0031] Because the solid-state RF source 12 is located outside the interior of the lamphead 16 of the UV system 10, there is no longer a balanced operation between sufficient cooling of the magnetron and cooling without overcooling the UV bulb 24. Thus, in some embodiments, the UV bulb 24 may be manufactured such that the center region has the same diameter as both end regions, so that more care and precision can be directed to cooling the UV bulb 24, for example via air knives and / or nozzles. Such a bulb configuration reduces the complexity and cost of manufacturing the UV bulb 24 compared to conventional bulbs, because there is no longer a narrow center region relative to both end regions.

[0032] Also, because the solid-state RF source 12 is located outside the interior of the lamphead 16 of the UV system 10, the lamphead 16 can be made smaller and lighter. As a result, the lamphead 16 can be easier to mount on and focus onto the substrate 26.

[0033] Both the solid state RF sources 12 and the cooling device 28 of the UV system 10 are coupled to a controller power supply 30. The controller power supply 30 can transmit a power signal and at least one control signal to each of the solid state RF sources 12 and the cooling device 28 to control the operation of each. For example, the controller power supply 30 can transmit a control signal to the solid state RF source 12 that defines the frequency of the RF energy to be generated. The controller power supply 30 can also include an interface for receiving user interaction and instructions. For example, based on the received user interaction, the controller power supply 30 can generate and transmit appropriate control signals to each of the solid state RF sources 12 and the cooling device 28. The controller power supply 30 can include any suitable computing device capable of generating control signals, such as a PC, processor, microprocessor-based controller, etc. In some embodiments, the controller power supply 30 is implemented as part of other devices described herein, such as the solid state RF sources 12 and the cooling device 28. In some embodiments, the controller power supply 30 includes a controller power supply incorporated within a separate housing or device. Each separate housing or device may be similarly implemented as part of other devices described herein.

[0034] FIG. 2 shows an exemplary UV system 40 that includes all of the features of UV system 10 , except that the cooling device 28 is located external to the lamphead 16 .

[0035] Instead of the illustrated antenna 18 and cable 20, the system 10, 40 may include a waveguide coupled to the solid-state RF source 12 and extending inside the lamp head 16. In this configuration, RF energy generated by the solid-state RF source 12 is conveyed by the waveguide toward the UV bulb 24, thereby causing its excitation and ignition. The waveguide may reduce the amount of RF energy lost during transmission compared to the antenna 18 and cable 20, but such an effect depends on the transmitted RF energy having a frequency that is directly proportional to the geometry of the waveguide. However, unlike magnetrons used in conventional UV systems, the solid-state RF source 12 can be finely tuned to a specific operating frequency. Thus, the cable 20 and antenna 18 provide an advantage over a waveguide when the generated RF frequency is variable, since the antenna 18 and cable 20 may be broadband and capable of transmitting a wider range of RF frequencies than a waveguide. For example, a waveguide may not be able to effectively transmit an RF signal that is tuned to a frequency different than the frequency for which the waveguide is intended.

[0036] Additionally, the configuration of the antenna 18 and cable 20 of the UV system 10, 40 allows for more uniform heating and excitation of the UV bulb 24 because multiple antennas 18 can be positioned around and / or precisely directed to emit FR energy toward different regions of the UV bulb 24. Such a configuration not only increases the overall efficiency of the UV system, but also reduces the size of the lamphead 16 because the antennas 18 and cable 20 can be configured to utilize a smaller footprint inside the lamphead 16 as compared to a waveguide.

[0037] Furthermore, unlike the unstable and frequency-separated RF signals generated by magnetrons in conventional systems, the solid-state RF sources 12 can be finely tuned to generate stable and uniform or nearly uniform frequency RF energy signals. As previously mentioned, the intensity of the UV energy generated by the UV bulb 24 is highly dependent on the RF energy applied. In fact, an RF energy signal of an unstable frequency can result in uneven and inefficient heating of the UV bulb 24, adversely affecting the intensity of the UV energy emitted therefrom. However, unlike magnetrons, which are known to generate unstable RF energy in substrate irradiation applications, the solid-state RF sources 12 can be finely tuned to specific frequencies, thereby increasing the amount of UV energy generated by the UV bulb 24.

[0038] Additionally, the solid-state RF source 12 begins generating RF energy more quickly upon start-up than the magnetrons used in conventional systems. As a result, the starter bulbs conventionally included in lampheads may be omitted, further reducing the size of the lamphead 16 and the power consumption by the UV system. In some embodiments, a frequency sweep of the solid-state RF source 12 is performed during start-up of the UV irradiation process and / or during ignition of the UV bulb 24 to further improve start-up time. Thus, the irradiation process may be started and stopped more quickly, improving system throughput.

[0039] FIG. 3 illustrates exemplary components of each solid-state RF source 12: an isolator 32 and a frequency detector 34.

[0040] The isolator 32 can allow RF energy to exit the solid-state RF source 12 while simultaneously preventing RF energy from entering the solid-state RF source 12. Thus, unlike multiple magnetrons, multiple solid-state RF sources 12 can each generate RF energy having the same or nearly the same frequency without the risk of adversely affecting each other. This results in more uniform and controllable heating of the UV bulbs 24.

[0041] A frequency detector 34 in the solid state RF source 12 can detect the frequency of the output RF energy and adjust the solid state RF source 12, if necessary, to maintain a desired RF frequency output during the irradiation process.

[0042] 4 is a schematic diagram of an exemplary UV system 50 having a solid-state RF source 12 positioned inside a lamphead 16 having a UV bulb 24 and a cooling device 28. In one embodiment of the UV system 50, an antenna 18 is coupled to the solid-state RF source by a small cable 20 (e.g., FIG. 1). Alternatively, the antenna 18 may be directly connected to the solid-state RF source. In yet another embodiment, the antenna 18 is coupled to the solid-state RF source 12 via other suitable intermediate elements, such as an impedance matching device or an impedance controlled cable. As with the UV systems 10, 40, each solid-state RF source 12 of the UV system 50 may be coupled to a single signal antenna 18, or each solid-state RF source 12 may be coupled to multiple antennas 18 via splitters.

[0043] Locating the solid-state RF source 12 inside the lamphead 16 offers certain advantages. For example, the closer or shorter the connection between the solid-state RF source 12 and the antenna 18, the less RF energy loss occurs during transmission of the RF energy to the UV bulb 24. Although locating the solid-state RF source 12 inside the lamphead 16 may increase the cooling requirements and the size of the lamphead 16, the lamphead 16 is still much smaller than the lampheads of typical conventional UV systems because the solid-state RF source 12 is thinner and smaller than the magnetrons used in conventional systems.

[0044] FIG. 5 is a schematic diagram of an exemplary UV system 60 having features of UV system 50 (FIG. 4), except that cooling device 28 is positioned external to lamphead 16 for cooling the contents of lamphead 16.

[0045] 6 is a flow chart 70 illustrating an exemplary sequence of operations performed during a UV irradiation process in which the substrate 26 is irradiated with UV energy. In step 72, a data signal and a power signal are transmitted from the controller power supply 30 and received by one or more solid-state RF sources 12. The data signal defines a desired frequency of RF energy to be generated by the solid-state RF source 12. Based on the data signal and the power signal, the solid-state RF source 12 generates RF energy having the desired frequency that was specified in the received data signal (step 74). Alternatively, the solid-state RF source 12 generates RF energy having a pre-characterized frequency. In yet another alternative, the solid-state RF source 12 generates RF energy having a default frequency without receiving a data signal defining a desired frequency.

[0046] At step 76, the generated RF energy is transmitted to the UV bulb 24 in the lamphead 16. In certain embodiments, the generated energy is transmitted, for example via at least one cable 20, to at least one antenna 18 contained within the lamphead 16 and coupled to the solid state RF source 12. In preferred embodiments, the generated RF energy is transmitted to multiple antennas 18. One or more antennas 18 are positioned proximate to the UV bulb 24, and the generated RF energy is transmitted to the UV bulb 24 by the multiple antennas 18 (step 78). In some embodiments, the solid state RF source 12 is located outside the lamphead 16, and transmitting the generated RF energy to the antenna 18 thus includes transmitting the generated RF energy from outside the lamphead 16 to inside the lamphead 16.

[0047] At step 80, the UV bulb 24 is excited and ignited by the generated RF energy, thereby causing the UV bulb 24 to generate UV energy. At step 82, the substrate 26 is irradiated with the generated UV energy by directing the UV energy toward the substrate 26 outside of the lamphead 16.

[0048] Throughout all of the foregoing steps, the sequence of operations may also include step 84 of cooling the contents of the lamphead 16, such as the UV bulb 24. While such cooling may be accomplished by an internal or external air blower, the sequence of operations may alternatively and / or additionally include directing a sheet of air at the UV bulb, for example with an internal or external air knife of the lamphead 16, during the irradiation process. Alternatively and / or additionally, the sequence of operations may include directing multiple internal or external jets of air at the lamphead 16, for example with multiple nozzles. The sheet of air and / or jets of air may be uniform, laminar, non-uniform, and / or turbulent. Additionally, the jets of air and / or sheet of air may be formed from compressed air and / or cooling air. In an exemplary embodiment, the compressed air and / or cooling air comprises an inert gas.

[0049] One or more of the steps described herein, such as step 72 of flowchart 70, may be implemented by computer program instructions provided to a processor of any type of computer to create a machine having a processor that executes instructions to perform the functions / operations specified herein. These computer program instructions may be stored in a non-transitory computer-readable medium that may direct a computer to function in a particular manner. To that end, the computer program instructions may be loaded onto a computer and cause the performance of one or more operational steps, thereby creating a computer-implemented process, such that the executed instructions provide a process for performing the functions / operations specified herein.

[0050] Additionally, any device or feature of the embodiments described herein may be described as "capable" of performing an action, whether it is configured to perform that action, whether it actively performs that action, or whether it exists to perform that action. The phrase "capable" is intended to refer to a broader reference to the device or feature.

[0051] Although the embodiments of the present invention have been illustrated by the description of various examples, and the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any manner limit the scope of the appended claims to such details. Additional advantages and modifications will be readily apparent to those skilled in the art. The features described herein may be combined in any manner depending upon the desired characteristics of the system or method. The invention, in its broader aspects, is not limited to the specific details and representative methods and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant's overall inventive concept.

Claims

1. 1. A UV system for irradiating a substrate, comprising: a lamp head having an interior; a solid state RF source capable of generating RF energy; a UV bulb positioned within the interior of the lamphead and capable of emitting UV energy when excited by RF energy generated by the solid state RF source; A system comprising:

2. The solid state RF source is positioned outside the interior of the lamphead.

2. The system of claim 1 .

3. a cooling device positioned outside the interior of the lamphead for directing cooling air to the UV bulb; 2. The system of claim 1, further comprising:

4. a cooling device positioned inside the interior of the lamphead for directing cooling air to the UV bulb.

2. The system of claim 1, further comprising:

5. at least one antenna coupled to the solid-state RF source and positioned proximate to the UV bulb; Further comprising: The antenna is capable of receiving RF energy from the solid-state RF source and directing the RF energy towards the UV bulb.

3. The system of claim 2.

6. The UV bulb has a length, The at least one antenna further comprises a plurality of antennas; The plurality of antennas are spaced apart along the length of the UV bulb.

6. The system of claim 5.

7. a cooling device positioned outside the interior of the lamphead for directing cooling air to the UV bulb; 7. The system of claim 6, further comprising:

8. a cooling device positioned inside the interior of the lamphead for directing cooling air to the UV bulb.

7. The system of claim 6, further comprising:

9. The solid state RF source is positioned outside the interior of the lamphead.

2. The system of claim 1 .

10. an RF transmitter coupled to the solid-state RF source and capable of receiving RF energy from the solid-state RF source and directing the RF energy towards the UV bulb; 10. The system of claim 9, further comprising:

11. The RF transmitter further includes at least one antenna. The system of claim 10.

12. The UV bulb has a length, The at least one antenna further comprises a plurality of antennas; The plurality of antennas are spaced apart along the length of the UV bulb. The system of claim 11 .

13. a cooling device positioned outside the interior of the lamphead for directing cooling air to the UV bulb; 13. The system of claim 12, further comprising:

14. a cooling device positioned inside the interior of the lamphead for directing cooling air to the UV bulb.

13. The system of claim 12, further comprising:

15. The RF transmitter further comprises a waveguide. The system of claim 10.

16. a cooling device positioned outside the interior of the lamphead for directing cooling air to the UV bulb; 10. The system of claim 9, further comprising:

17. a cooling device positioned inside the interior of the lamphead for directing cooling air to the UV bulb.

10. The system of claim 9, further comprising:

18. a controller for transmitting at least one control signal to the solid-state RF source; Further comprising: The control signal defines a frequency of RF energy generated by the solid-state RF source.

2. The system of claim 1 .

19. at least one additional solid-state RF source capable of generating RF energy; 2. The system of claim 1, further comprising:

20. The plurality of solid state RF sources are positioned outside the interior of the lamphead.

20. The system of claim 19.

21. a controller for transmitting at least one control signal to each of said plurality of solid-state RF sources, Further comprising: Each control signal defines the frequency of the RF energy generated by each solid-state RF source.

21. The system of claim 20.

22. The plurality of solid state RF sources are positioned inside the interior of the lamphead.

20. The system of claim 19.

23. a controller for transmitting at least one control signal to each of said plurality of solid-state RF sources, Further comprising: Each control signal defines the frequency of the RF energy generated by each solid-state RF source.

23. The system of claim 22.

24. 1. A method of irradiating a substrate with UV energy, comprising: generating RF energy with a solid-state RF source; transmitting the generated RF energy to a UV bulb in the lamphead; igniting the UV bulb with the generated RF energy; generating UV energy from the UV bulb being ignited; irradiating a substrate with the UV energy by directing the UV energy at the substrate outside of the lamphead; A method comprising:

25. generating a first data signal; receiving the first data signal with a solid state RF source that defines a first desired frequency for generated RF energy; Further comprising: The step of generating the RF energy with the solid-state RF source comprises: generating RF energy having the first desired frequency with the solid-state RF source; igniting the UV bulb with the generated additional RF energy; Contains 25. The method of claim 24.

26. generating a second data signal; receiving the second data signal with a second solid state RF source defining a second desired frequency equal to the first desired frequency; generating additional RF energy having the second desired frequency with the second solid-state RF source; transmitting the generated additional RF energy to the UV bulb; igniting the UV bulb with the generated additional RF energy; 26. The method of claim 25 further comprising:

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