JP7588269B1 - Excimer Instruments - Google Patents

Abstract

To provide an excimer instrument that provides inexpensive UV germicidal illumination that is adept at killing pathogens without harming humans present under any circumstances.
The excimer instrument includes a krypton/chloride bulb configured to emit a beam of far UV-C light through the filter and then through the diffusing layer into an occupyable space, and the diffusing layer is configured to diffuse the beam of far UV-C light.
[Selected Figure] Figure 1

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 17/080,390, filed Oct. 26, 2020, and entitled "CARTRIDGE BASED UV C STERILIZATION SYSTEM," which claims the benefit of U.S. Provisional Patent Application Ser. No. 63/069,436, filed Aug. 24, 2020, and entitled "HUMAN SAFE UV C STERILIZATION SYSTEM," which are incorporated herein in their entireties for all purposes.

[0002] The system of the present invention is in the field of ultraviolet light disinfection, specifically in the C-band wavelengths (UV-C). Such disinfection is currently used in hospital operating rooms, burn wards, and similar areas requiring a high degree of disinfection. The key difference with these existing uses is that the system of the present invention is safe for use in the presence of people and living tissue.

[0003] The coronavirus pandemic has changed many aspects of human life in every country. These changes will continue even after the virus is weakened by vaccines and antibodies. People are no longer comfortable in close proximity to others in public places. Routine flu and cold infections are now treated with many of the same techniques used during the pandemic.

[0004] UV has three different bands: A, B, and C. UV-A is the band commonly associated with "black light" and black light fluorescence. UV-A has the longest wavelength of the three bands and is the least effective at killing viruses, bacteria, and similar pathogens. Its wavelengths are between 315 nm and 400 nm.

[0005] UV-B is the wavelength most suitable for use by tanning salons. UV-B is dangerous to use excessively around living organisms because it is both powerful enough to cause burns and has a wavelength long enough to penetrate cells and cause irreparable genetic damage. Its wavelength is between 280 nm and 315 nm.

[0006] UV-C is recognized as one of the most effective wavelengths for killing microbes because the shorter wavelengths are more powerful. Only recently has it been discovered that some wavelengths in this band are long enough to kill microbes and short enough not to penetrate living cells, which are many times larger than the tiny microbes one wishes to kill. UV-C is between 100 nm and 280 nm, with wavelengths generally considered safe for human tissue exposure being between 200 nm and 230 nm. UV-C creates undesirable ozone, especially at wavelengths below 200 nm.

[0007] Studies have shown that hairless mice can be exposed to more than 20 times the amount of 200-230 nm UV-C radiation currently proposed for humans, for 8 hours a day, without any ill effects. These studies have been carried out at universities in Japan and Columbia University in the US. These studies have been extended for up to 6 months, still with no ill effects. Recently, tests have also been carried out on Japanese humans at 250 times the exposure required to kill 99.9% of pathogens. Subjects showed no ill effects, no sunburn whatsoever.

[0008] There are several technologies that can produce germicidal wavelengths of UV light. Gas discharge lamps have a long history and, depending on the gas used, can kill pathogens. Low pressure mercury produces 254 nm and has been the standard for decades. Low pressure mercury is essentially fluorescent with no phosphor inside to convert the UV light to visible light. LEDs have recently become commercially available in the UV-A and UV-B spectrum, but they are very inefficient. There are also several longer wavelengths in the UV-C spectrum. A Japanese research project has recently created LEDs in the lower 200 nm, which is the safer part of the UV-C spectrum, but these are very inefficient and not practical for immediate commercialization.

[0009] Several companies make UV-C excimer fixtures that emit at 222 nm, such as Ushio's 12 W Care 222 and others such as Eden Park's Flat Excimer Lamps. The Ushio fixture has a flat faceplate filter separate from the bulb that blocks all the undesirable spectrum produced by the bulb (this spectrum is all wavelengths above about 237 nm). The Eden Park device currently has no filter attached and therefore radiates 25% of its energy in the dangerous wavelengths from 230 nm to at least 380 nm.

[0010] If these filters are not in place, the lights will emit a spectrum that is not safe for living tissue. If a maintenance worker attempts to change a light bulb, the worker will be exposed to harmful light. If the glass filters are broken or degraded, the user will be placed in a dangerous situation.

[0011] Finally, the materials used are also important. UV-C cannot penetrate plastics and many glasses. Only quartz glass can be used to emit UV-C light without significant losses or downlighting failure. Nitrogen and moisture in the air also absorb or block UV-C when it is transmitted through the air from very far away.

[0012] There is a need for an inexpensive UV germicidal illuminator that does a good job of killing pathogens without harming people present under any circumstances.

[0013] The device of the present invention provides a human-safe UV-C germicidal light bulb that can be used in continuous public locations. The light bulb is safe in all conditions, efficient, affordable, and can monitor itself and provide status notifications.

[0014] Although Columbia University research has shown that a pass filter tuned to 200-230 nm kills pathogens and does not harm human cells, the device of the present invention will utilize 207 nm or 222 nm excimer technology combined with an integrated band pass filter that blocks the entire spectrum above 234 nm. This small change in filtering results in 2.5 times more usable radiation than the 200-230 nm version, with almost no radiation in the 230-232 nm range. Ushio has a product that filters from 237 nm, but this runs the risk of allowing very harmful radiation to pass. Ideally, the filter material is deposited directly on the bulb envelope, which is made of quartz glass. This blocks all harmful light even when handling during installation or maintenance. The 207 nm version requires bromine (Br), argon, and krypton (Kr) gases. The 222 nm version uses krypton (Kr) and chloride (Cl). The filter material is ideally very pure hafnium oxide deposited at 2-3 μm to create a cutoff filter 234-400 nm at a depth of about 0.0001. This type of excimer bulb ideally uses a Dielectric Barrier Discharge (DBD). This is where the two main electrodes are on the outer part of the quartz envelope, and very high voltages of several thousand volts are required to activate the gas. As a result, the gas inside the envelope does not come into contact with any metal that could contaminate the gas. Some Ushio lights have one conductor inside the envelope (some hybrid short arc/DBD bulbs). By keeping all the electrodes on the outer part of the envelope, the device of the present invention avoids the problems of dissimilar materials and envelope contamination, and avoids the problems of needing multiple types of glass as Ushio does. Although this inventive lamp requires a high arc voltage, this is only a small hurdle for all the benefits offered by a quartz-only envelope solution.

[0015] An integrated bandpass filter can be applied onto a separate piece of quartz that is permanently attached to the bulb envelope using a UV compatible adhesive around the edges. The filter is integrated into the complete assembly. This protects the user from UV exposure in all conditions, including changing and maintaining the bulb.

[0016] The safe DBD device of the present invention has an integrated captured reflector on the rear side of the bulb envelope and two additional integrated mirrors, one on each side of the bulb, set at 45 degrees to the filter plane to maximize light exit. Light transmitted through the filter is significantly attenuated at any angle other than perfectly normal to the filter plane. Light transmitted at 10 degrees from normal can be attenuated by 50%, depending on the filter composition. Larger angles result in increased attenuation and absorption.

[0017] The reflector can be a separate material that is permanently attached to the bulb envelope using a UV compatible adhesive around the edges. The bulb shape is ideally a flattened quartz tube where the two flattened sides are parallel to each other. This design is the cheapest and easiest to construct and is scalable. Another desirable, but not optimal, bulb shape could be a tube-based design with a complex shape that allows the reflector on the back side to be optimized for a variety of beam angles and patterns. A flattened circular tube-based bulb will emit a Lambertian pattern if desired.

[0018] The safety DBD bulb of the present invention is cartridge based with exposed rigid conductor for easy replacement. The useful life of 222 nm excimer bulbs is typically about 8000 hours (at 10% brightness loss) from which it degrades rapidly. The high voltage and driver of the excimer bulb are unique and cannot be connected to other power sources, therefore each different electrode power/size requires a unique connector to avoid connections between electrically incompatible components, and polarization is also desired. The high voltage main electrode is ideally a conductive ink made of silver or similar conductive metal printed in a mesh pattern over the non-transparent or filter area. Additionally, the second main electrode is 0 volts and uses conductive ink. This reduces parts. Due to the use of high voltage in the excimer bulb, a safety shutoff switch should be included in the fixture of the present invention to allow maintenance personnel to safely replace the bulb once the fixture is opened.

[0019] Such safety light bulbs further include a built-in smart chip with a non-resettable serial number, date of manufacture, date of use, temperature boundaries, and a Hobbs meter or hour meter. The smart chip ideally utilizes encryption so that it cannot be hacked. The light bulb fixture communicates with the smart chip on the light bulb, and the fixture has Internet Of Things (IOT) connectivity. The light bulb fixture monitors the life of the light bulb and when the light bulb was first turned on, and will shut down the light bulb if it is running too hot, nearing the end, etc. This protects the user if the filter is starting to degrade or the light intensity is not up to specification. This can be notified or collected by the maintenance management software and a replacement can be requested. IOT connectivity can be used to communicate with remote sensors that measure the output at various points in the environment around the fixture to which people are exposed. Because this type of bulb does not emit a lot of visible light, the fixture should have a multi-color LED indicator so that the user can quickly tell at a glance if the fixture is working properly or not.

[0020] Because light output degrades over time and the safety fixture of the present invention has feedback regarding the light level of the environment, the output can be increased over time to ensure the fixture has a constant output level. The fixture ideally has a light sensor to determine the light output. Since the output level can be estimated by time of use and by a table that can be programmed into the fixture, the fixture can always increase the output power to achieve a nearly constant lumen output or at least a good estimate.

[0021] When emitting germ-killing light and exposing the public to this light, absolute safety is the primary criterion that must be met and that must be tested and verified. The safety measures built into the device should not be expensive, but should be what is necessary to allow public exposure to UV-C light.

[0022] When entering an area protected by the device of the present invention, the public should have access to the collected data. The public may ask questions such as "What is the length of time it will kill germs on surfaces and in the air?", "At what percentage of power is this system operating?", "How many hours per day can a person spend in this environment?"

[0023] The nature of DBD excimer bulbs is that they require adequate cooling as the gas can become overheated, thereby reducing the illumination level. The safety bulb of the present invention may have a ceramic or metal heat sink on the rear side. The envelope may be protruding with linear fins to increase the surface area for convection cooling, similar to the approach taken when designing an aluminum heat sink. The fins are placed on the outer portion of the light-emitting envelope. A fan may blow air over the bulb to reduce the gas temperature, especially at increasing power levels. A temperature sensor may be part of the bulb to provide temperature feedback, and the fan speed may be adjusted to keep the envelope temperature constant.

[0024] Another reality of excimer bulbs is that they can sometimes be difficult to start in cold conditions, requiring a coil filament, resistor, or similar heating element to preheat the gas. These can be used to preheat safety UV-C bulbs at cold temperatures or even during normal start-up, either inside the quartz envelope or ideally outside the quartz envelope, or encased in a ceramic heat sink. The power supply in the fixture must have additional circuitry to allow for this feature. The fixture of the present invention uses a pulsed square wave, rather than a sine wave, to drive the bulb. Sine wave power is the standard for these high voltage applications, but not all of the energy below the peak voltage of the sine wave is converted to light, but simply produces heat.

[0025] The safety device of the present invention can use either 222 nm or 207 nm chemistry or both. The use of two separate envelopes allows for tailoring of specific wavelengths to best kill emerging pathogens. Each chemistry has a different drive voltage and arc gap, but the power supply can be easily configured to drive either one or both simultaneously. Ideally, the device of the present invention uses DBD, where the electrodes are placed on the outer portion of the glass envelope. This type of discharge requires very high voltages to activate the gas inside, but by using this technology, the gas inside the envelope never becomes contaminated by electrode corrosion (a common problem with gas discharge lamps when used over time).

[0026] The safety light bulb of the present invention is used in an environment where normal visible light emerges from the lighting fixture, but the light bulb of the present invention can be combined with a conventional light source in a single fixture. If there are any objectionable visible colors emitted from the UV-C portion of the fixture, the spectrum of visible light can be altered and mixed to normalize the color mix or average of colors emerging from the fixture. This type of fixture is ideally a "canister" and this type of fixture is mounted in a circular hole in the ceiling.

[0027] The safety system of the present invention can be packaged as a typical light bulb. A current ballast or power source can be fitted into the base, and the bulb can illuminate in all directions like an LED or compact fluorescent bulb, or it can include a traditional illuminator.

[0028] The above has outlined broadly the more important features of the invention disclosed herein so that the detailed description that follows may be more clearly understood and the inventor's contributions to the art may be better appreciated. The invention is not limited in its application to the details of construction or the arrangement of components set forth in the following description or illustrated in the drawings. Rather, the invention is capable of other embodiments and may be practiced and carried out in various other ways not specifically recited herein. In addition, the following disclosure is intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, it is to be understood that the terms and terminology employed herein are for the purpose of description and should not be considered limiting unless specifically limited herein.

[0029] FIG. 1 is a diagram from a photograph showing a low voltage mercury bulb (prior art). FIG. 1 is a diagram from a photograph showing an Ushio Care 222 excimer bulb and driver (prior art). [0031] FIG. 1 is a diagram from a photograph showing an Eden Park flat excimer lamp (prior art). [0032] FIG. 1 is a spectral diagram showing Br—Kr emission at 207 nm. [0033] FIG. 1 is a spectral diagram showing 222 nm Kr—Cl emission. [0034] FIG. 1 is a spectral diagram showing Br-Kr emission at 207 nm with appropriate filtering. [0035] FIG. 1 is a spectral diagram showing 222 nm Kr—Cl radiation with appropriate filtering. [0036] FIG. 1 illustrates a basic light bulb. [0037] FIG. 1 is an exploded isometric view of a bulb assembly. [0038] FIG. 1 is a cross-sectional side view of a bulb assembly. [0039] FIG. 1 is an isometric view of a bulb cartridge. [0040] FIG. 1 is an exploded view of a multi-valve instrument. [0041] FIG. 1 illustrates a downward facing fixture with a bulb facing straight down. [0042] FIG. 1 illustrates a downward facing fixture with a bulb facing outward at 45 degrees. [0043] FIG. 1 illustrates a safety light bulb heat sink with a heated filament. [0044] FIG. 1 illustrates a safety light bulb with both UV-C and general illuminator elements. [0045] FIG. 1 illustrates a temperature regulated fixture with a fan cooled safety bulb. [0046] FIG. 1 is a block diagram illustrating an appliance having a driver, a bulb, a temperature sensor, and a safety shut-off switch located within the appliance. [0047] FIG. 1 is a network diagram showing an IoT light bulb and system. [0048] FIG. 13 illustrates the output of a pulsed wave power supply compared to a sine wave. [0049] FIG. 13 illustrates the output of a pulsed wave power supply at full power and during dimming. [0050] FIG. 1 illustrates a UV-C bulb cooled by a single-phase dielectric fluid. [0051] FIG. 1 illustrates a liquid-cooled high power excimer lamp of the present disclosure. [0052] FIG. 1 is a block diagram illustrating a liquid-cooled lamp of the present disclosure with a coolant system for achieving a high power excimer instrument.

[0053] The embodiments of the present specification and various features and advantageous details thereof will be more fully described with reference to the non-limiting embodiments shown in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processes and manufacturing techniques are omitted so as not to unnecessarily obscure the embodiments of the present specification. The examples used herein are intended merely to facilitate an understanding of the manner in which the inventions of the present specification may be practiced, and further to enable those skilled in the art to practice the embodiments of the present specification. Thus, the examples should not be construed as limiting the scope of the invention as claimed.

[0054] Before describing the invention in detail, it is important to understand that the invention is not limited in its application to the configurations shown herein and to the details of the steps described herein. The invention is capable of other embodiments and of being practiced or carried out in various ways. It will be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation.

[0055] Referring now to the drawings, in which like reference numerals denote the same parts throughout the several views, a typical diagram of a (current art) low pressure mercury bulb 100 is shown in FIG. 1. The bulb 100 has several components: electrical contacts 102 and 104, a metal support structure 106, a main electrode 108, mercury argon gas 110, an outer envelope 112, a tip support 114, a striking electrode 116, a resistor 118, a glass base 120, and a second main electrode 122.

[0056] A newer alternative technology is shown in FIG. 2, where an Ushio Care 222 excimer bulb and driver system 200 is shown in block diagram form. A bulb 202 is driven by a driver 204 via two wires 206 and 208. The bulb has two main electrodes 210 and 212. The housing and filter are separate and not shown.

[0057] The next drawing in FIG. 3 shows a flat version of an excimer bulb, the Eden Park Flat Excimer Lamp 300. This excimer bulb has two closely spaced flat sheets of quartz glass 302 and 304 with electrodes 306 and 308 on the outer portions of the front plate 310 and back plate 312. The bulb has no filters or reflectors.

[0058] In FIG. 4, a spectral diagram of Br-Kr radiation 400 at 207 nm is shown. The main emission spike 402 at 207 nm is a wavelength that is safe for human tissue and is lethal to microscopic pathogens such as viruses and bacteria. Also shown is a small amount of radiation 204 at 230 nm that is on the danger edge of the spectrum that is incompatible with human exposure. Additional radiation 406 at 270 nm is shown that is very dangerous for human exposure even at these low levels. Finally, a spike 408 of radiation at 290 nm is shown, which is not safe for human exposure.

[0059] In FIG. 5, there is a spectrum of a different chemistry than that shown above, this is Kr-Cl radiation 500 at 222 nm. The main radiation spike 402 at 222 nm is a wavelength that is safe for human tissue and lethal to microscopic pathogens such as viruses and bacteria, but continues at low levels up to the lethal 240 nm 504 range. Additionally, there is a small bump of radiation at the 260 nm range 506, which is very dangerous even at such low levels.

[0060] In FIG. 6, a spectrum diagram of safe 207 nm Br-Kr radiation 600 is shown, with a spike 602 at 207 nm. 207 nm is a wavelength that is safe for human tissue and lethal to microscopic pathogens such as viruses and bacteria, but there is no radiation at dangerous wavelengths due to subtractive filtering.

[0061] In FIG. 7, a spectrum diagram of safe 222 nm Kr-Cl radiation 700 is shown, with a spike 702 at 222 nm. 227 nm is a wavelength that is safe for human tissue and lethal to microscopic pathogens such as viruses and bacteria, but there is no radiation at dangerous wavelengths due to subtractive filtering.

[0062] In FIG. 8, an excimer bulb 800 of the present invention is shown. Bulb 800 has a quartz envelope 802 that contains a combination of gases at a pressure of about 30 kPa (300 mbar) depending on the particular chemistry involved (207 nm Br-Kr or 222 nm Kr-Cl). The two flattened sides are parallel to each other and are about 10 mm apart, which varies with various power levels, fill pressures, and drive voltages.

[0063] The quartz envelope 800 is initially cylindrical and is heated and drawn through rollers to flatten two sides, the front face 802 and the back face 804, so that they are parallel to each other. The ends of this flattened tube are then sealed at both ends 806 and 808 by heat welding to seal both ends 806 and 808. The fill point 810 shown starts out as a small fill tube that melts shut after the bulb is cleaned and filled with low pressure gas. The sides 812 and 814 of the bulb, the right side 812 and the left side 814, allow more light to pass through. These light paths were ignored in prior art devices, but a large amount of unused light energy is utilized by this location in the device of the present invention.

[0064] FIG. 9 shows an exploded view of a safe flattened tube design bulb assembly cartridge 900. The bulb 800 starts as the center of the assembly. The front electrode 902 is a grounded or 0 volt electrical grid and is placed directly facing the quartz bulb face 802. The front electrode 902 can be made of a non-corroding conductive metal such as molybdenum or silver. Ideally, this front grid 902 or front screen will be closest to the user, which is why the ground or 0 volt potential was chosen on this side. To eliminate ozone production, the grid will be applied as a conductive liquid or ink to eliminate oxygen from the electrical path. Similarly, the rear electrode 904 is the positive electrode. The rear electrode 904 is also placed directly facing the rear side 804 of the quartz envelope. The voltage on this side is approximately 10,000 volts and is placed as far away from the user as possible. This electrode 904 is plated or painted with a conductive ink to eliminate oxygen from getting between the conductive electrode and the high voltage electrical path.

[0065] A back reflector 908 is added facing the outer portion of the rear electrode 904. The back reflector 908 and rear grid 904 may be combined as one piece for both conducting electricity and reflecting light, and thus may be vapor plated onto an aluminum layer that is applied directly to the back surface 804 of the bulb 800, further minimizing parts and cost. Side reflectors 926 and 928 are set at a 45 degree angle to capture light leaking out the sides 812 and 814 of the bulb 800 and direct it directly forward and parallel to the light emitted from the main surface 804 of the bulb 800. A UV filter plate 906 is placed as close as possible to the two side reflectors 926 and 928 and the front electrode 902 and is made of polished quartz and a plated layer of hafnium oxide, forming a narrow bandpass filter in the range of 200 nm to 234 nm.

[0066] The heat sink 910 may be aluminum, but ideally is ceramic to provide electrical insulation for the high voltage rear electrode 904. The heat sink 910 would block all unfiltered light that would pass through the cracks between the mirrors 908, 926, and 928, or radiate out the ends of the bulb 800. Ideally, the heat sink 910 would also incorporate many of the individual elements of the bulb assembly mentioned above, including the bulb 800, the back reflector 908, the side reflectors 926 and 928, the rear electrode 904, the front electrode 902, and the front filter plate 906, and the heat sink 901 would be tightly sealed using a UV compatible epoxy that would be used around the edges of the electrodes 812, thereby stabilizing the mechanical connection between these components and completely sealing off air and dust ingress. Existing art designs allow air to be blown directly onto the bulb, thus allowing dust to adhere to the interior surfaces of the bulb and filter over time. Dust can absorb a lot of UV-C light and becomes very inefficient very quickly. The device of the present invention uses end caps 912 and 914 to make a sealed cartridge 900 to keep dust out of these surfaces. These end caps 912 and 914 of the electrode assembly 900 are made from ceramic, and the end cap 912 will encapsulate the thermal sensor and smart chip 916, and also provide a mechanical rotating tip for the bulb with detents 918 for pre-set individual positioning within the fixture. This means that the light emitting cartridge has no wires to connect to or floating leads. The smart chip and temperature sensor 916 has operation meter time, serial number, manufacturing date, temperature, out of range flag, and encrypted communication capabilities to prevent false operation. There is a conductive jumper 930 connected to the front electrode 902, which is electrically connected by a conductive pin 920 through the ceramic end cap 912. Similarly, there is a conductive jumper 932 connected to the rear electrode 904, which is electrically connected to a conductive pin 922 through the ceramic end cap 914. There are three plated-on conductive traces 924 around the ceramic end cap 912 that are connected to the smart chip and thermosensor 916. These traces 924 allow communication from the bulb cartridge 900 to contacts on the fixture receiver to allow the fixture to communicate with these chips 916. Such mechanical and electrical connections are well understood by those skilled in the art, but other connection methods may be used. In this assembly, all high voltage parts are insulated and removed from anyone handling or exposed to high voltage parts, making it easy to replace the hermetically sealed safety UV-C bulb cartridge.

[0067] FIG. 10 shows a side cross-sectional view of an assembled safety UV-C light bulb cartridge 900. The light bulb 800 has a negative electrode 904 that is plated or attached directly to the quartz. Similarly, the positive electrode 902 is attached directly to the front surface 804 of the light bulb 800. Behind the negative electrode 904 is a back reflector 908. A right side reflector 926 and a left side reflector 928 are angled at a 45 degree angle to the front surface 804. All of the right side reflector 926 and left side reflector 928 are captured and surrounded by a ceramic heat sink 910. There is a small air gap between the light bulb 800 and the filter 906 that is sealed by a piece of ceramic and ideally a UV resistant sealant.

[0068] FIG. 11 shows an assembled safe UV-C bulb cartridge 900. The assembled cartridge 900 has an optical aperture 1102 sealed around the edges, so that air and dust, as well as unfiltered light, are prevented from passing through.

[0069] FIG. 12 shows an exploded view of a variable beam angle multi-cartridge fixture 1200. Each of the three bulb cartridges or heads 900 sits in a ceramic saddle 1218 that has a conductive spring clip 1220 that holds the metal pins 920 and 922 of the bulb cartridge 900 and also connects power to the bulb cartridge 900. The saddle 1218 and corresponding end cap 912 at one end have a different size than the saddle 1218 and corresponding end cap 914 at the other end, thereby polarizing the ends so that the electrode cartridge 900 can only be inserted in one direction, with the zero potential 902 always on the forward side and the high potential 904 always on the rear side, away from the user.

[0070] A saddle 1218 further holds a detent spring 1216 that fits with detent projections and detent grooves on the bulb end caps 912 and 914. This allows the bulb cartridge 900 to have multiple precise angles that can be easily set, allowing the spring 1216 to hold the bulb cartridge 900 in each position, yet still allow finger pressure to snap the bulb cartridge 900 into the next detent position. The front bezel 122 of the fixture rotates away from the base 1202 by a latch and a hinge connection 1208 between the front bezel 1222 and the rear housing 1202, thereby exposing the electrode cartridge 900 for maintenance and replacement. When the front bezel 1222 is fully closed, it presses a safety switch 1210 located in the rear housing 1202, allowing the pressed microswitch 1210 to power the fixture 1200. Proximity and distance are determined by a distance sensor 1214 that looks through a small hole in the bezel 1222 to determine the distance to the nearest object or floor. Data from the safety switch 1210, distance sensor 1214, and the smart chip and thermo sensor 916 of the three bulb cartridge are all connected to and conditioned by the smart power supply 1204. The power supply 1204 also has digital communication capabilities such as Wi-Fi and Ethernet to name a few. Air is drawn in through perforations in the front bezel 1222 by a fan 1206 supported by a fan frame 1224, which then blows the air over the top of the power supply 1204 and over the heat sink 910 of the bulb cartridge and out through holes in the base 1202. The power supply 1204 measures the temperature of the bulb cartridge 900 and modifies the speed of the fan 1206 for optimal efficiency of the bulb cartridge 900. The mounting plate 1226 can be first installed on a standard electrical box found in the existing architectural situation, then the mounting plate 1226 can be snapped onto the rear housing and rotated in the rear housing track, allowing the upper bezel to point to infinity. Because UV-C light filters tend to transmit light only at narrow angles, the emitted light tends to be a narrow beam. This inventive fixture allows multiple heads in a single fixture to provide a wide beam and asymmetric light distribution to best fit the widest range of environmental constraints. Ideally, the fixture would have an illuminated indicator 1228 to indicate function and/or malfunction from a distance, in this example the indicator 1228 is a backlit logo. Although the preferred embodiment shows three bulbs in the fixture, any number of bulbs may be used with the inventive device.

[0071] FIG. 13 shows a downward facing fixture with bulbs 1300 positioned to point straight down. The fixture 1200 has three bulb cartridges 900 pointing straight down (1302) for a tight beam angle under the fixture 1200. This creates the narrowest beam possible for the fixture and would be used in situations where there are very high ceilings or the emitted light needs to be concentrated.

[0072] FIG. 14 shows a downward facing fixture with bulbs 1400 positioned at 45 degrees, where the fixture 1200 has three bulb cartridges 900 each facing outward at 45 degrees (1402). The wide beam angle below the fixture 1200 would be used in lower ceilings or in multiple areas to cover a very large area.

[0073] FIG. 15 shows a safety light bulb heat sink with a heating filament 1500. The heat sink 910 can be modified to have a heating element 1502 permanently attached through a hole in the heat sink or simply embedded in the ceramic along its longitudinal axis. This heated heat sink 1500 conducts heat to the light bulb 800, warming the gas inside, allowing the gas to ignite when required. Electric heating elements 1502 have been around for over 100 years and are well known to those skilled in the art. This heating element 1502 is controlled by the smart power supply 1204 when needed to start the fixture 1200 during cold conditions. When the light bulb 900 is operating, it can warm up and the heating element 1502 can be turned off. The present invention requires additional electrical contacts in addition to the excimer bulb assembly.

[0074] FIG. 16 shows a side view of a screw-in UV-C safety light bulb 1600. For illustrative purposes only, the description utilizes a floodlight type light bulb 1602, however, any type of screw-in light bulb is applicable in the present disclosure and the disclosure is not intended to be limiting in any way, but merely an example. A safety light bulb 1600 having both a UV-C element and a general illuminator element is disposed inside a screw-in light bulb housing 1602. Conventional electrical contacts of the screw-in light bulbs 1612 and 1614 extend to a driver/power supply 1204. Additionally, the driver/power supply 1204 powers the UV-C portion 900 of the safety light bulb 1604 with both UV-C and general illuminator elements via wires 1606 on a circuit board 1616, where the wires extend to a clip mounted on the circuit board (clip not shown for simplicity). Additionally, the driver/power supply 1204 separately powers the white LED 1604 portion via wire 1608. The translucent surface 1610 of the screw-in UV-C safety light bulb 1600 should be made of quartz glass, ideally with a diffusing surface such as sandblasted or other texture. UV-C is absorbed by any plastic cover or traditional glass cover. The flattened cylindrical light bulb 900 of the present invention is combined with multiple LEDs 1604 on a circuit board 1616. The LEDs may all be white monochromatic, or they may be a mixture of multiple colors or a mixture of different color temperatures, with individual LEDs 1604 controlling the mixing of the various colored LEDs 1064. The color of light emitted by only the safety UV-C portion of this device of the present invention is optically not high brightness to the human eye, and includes a pinkish purple hue. The white LED may be insufficiently pink or purple, so that when both the safe UV-C and white LEDs are turned on, the combined light has a neutral color spectrum.

[0075] FIG. 17 shows a fixture using a flattened cylindrical safety UV-C bulb fixture 1700 that is temperature regulated and fan cooled. A smart power supply 1204 communicates with a smart chip 916 in the bulb 900 via low voltage data lines. A small muffin fan 1206 resides above the heat sink 910 and blows downwards on the heat sink 910 and the bulb 900. The fan is controlled and powered by the driver/power supply 1204. A thermal sensor 916 encased inside the ceramic base is queried by the smart driver/power supply 1204. Based on the power sent to the bulb 900 and the temperature reported, the driver/power supply 1204 drives the fan 1206 to the appropriate speed, thereby regulating the temperature of the bulb 900 in a closed loop. The heat sink 910 may or may not be required. The reason is that a bulb that operates at low power may not require a heat sink 910, while a bulb that operates at high power may require a large heat sink, or may require, for example and without limitation, a pin-fin heat sink 910. The driver/power supply 1204 also powers the resistive heater when the bulb 900 is not on and the thermal sensor detects that the bulb ignition may not be possible due to low temperature. In this case, the driver/power supply 1204 powers the resistive heater before applying power to the bulb 900. Then, when the bulb 900 operates, it may be necessary for the driver/power supply 1204 to power the fan 1206 to cool the bulb 900. The power supply in the fixture of the present invention powers the excimer bulb using pulsed high voltage DC power. The width of the individual pulse waves may be changed to control the brightness of the bulb 900, or some of the pulse waves may simply be skipped to reduce the light output. Currently, most excimer bulbs are driven by sinusoidal power supplies and have excess non-recoverable energy below 9,000 volts. This energy simply heats the envelope and produces no light. The pulse wave may have a slightly rounded top edge and other parts may look like a square wave, the pulse wave has straight edges and no unusable power. The predicted output of the bulb over time can be programmed into the power supply so that when the hour meter in the bulb ages and notifies the power supply, it can increase the power slightly to compensate for the low efficiency and output a constant lumen over time.

[0076] FIG. 18 is a block diagram of the driver, bulb 900, distance and proximity sensor 1214, light level sensor 1224, smart chip 916, and safety shut off switch 1210 in the fixture housing. The bulb 900 is connected to a driver/power supply 1204. The driver/power supply 1204 has a switch 1210 wired to the door or front bezel 1222 of the fixture housing so that whenever the door 122 is open, the power to the bulb 900 is turned off. This is a particularly important safety issue since the excimer light can operate using thousands of volts. The driver/power supply 1204 communicates with the smart chip 916 and, through communication with the smart chip, verifies that the bulb 900 is valid, has not been tampered with, and is a valid replacement. Fake bulbs will most likely not have a pass filter and will radiate dangerous wavelengths towards the user. A distance/proximity sensor 1214 can ensure that the output power level is appropriate for the distance to the ground and vary the output power level to the bulb based on the distance. The proximity sensor 1214 and smart power supply 1204 attempt to reduce or turn off the power level if they detect an object that is too close, such as when a maintenance person is attempting to work on the fixture 1200. The proximity sensor and distance sensor 1214 can be the same sensor. A UVC light level intensity sensor 1224 can observe the ground or the bulb. The UVC light level intensity sensor 1224 is filtered to only sense wavelengths between 200 nm and 230 nm. The UVC light level intensity sensor 1224 can determine the overall light output and the smart power supply/driver can use this information to adjust the output for a constant lumen output. The smart functions of the power supply 1204 can be moved to a separate circuit board, which can then control the power supply 1204. Such functions are well known to those skilled in the art.

[0077] FIG. 19 is a network diagram of an IoT light bulb and system 1900. The device 1200 of the present invention can have an LED 1228 on the basic luminaire 1200 to indicate that the device is on and disinfecting. This LED 1228 can be a constant LED 1228 or an intermittent LED 1228. Similar to a smoke detector, the illuminator 1200 will have a single color IE blue or green "good" or "OK" when functioning properly and another color IE amber or red "attention" or "error". The indicator 1228 can be in the form of a backlit logo.

[0078] A person entering the room can quickly see if the illuminator 1200 is functioning or needs maintenance by looking at the LEDs 1228. The LEDs 1228 can also indicate the power level. When there is a low activity event and low bacteria load event, one LED can be on, and when there is a high activity event with increasing bacteria load, the illuminator increases the power output and the LED 1228 changes to indicate this event. The fixture can receive data from a crowd density sensor and use this information to set the output power level.

[0079] Crowd density sensors 1906 such as CrowdScan 1906, an rf monitor from Antwerp, or Density 1906, a Lidar-based device from San Francisco, have the ability to determine how many people are in a given space at a given time without violating people's privacy, i.e., without using camera or cell phone tapping technology. There are several other services similar to these. These are simply examples of crowd density sensors 1906 that communicate as IoT 1906 and with Internet resources such as the device 1900 of the present invention.

[0080] The illuminator 1200 can integrate multiple different types of communication 1904, including Bluetooth 1904, WiFi 1904, Cellular 1904, Sidewalk from Google 1904, and hardwired technologies 1904. This communication 1904 allows for monitoring of the functionality of the illuminator and allows for remote control of the illuminator by remote means.

[0081] The illuminator 1200 may have a local mechanical control system, such as a simple on/off switch or a dimmable light switch. The illuminator 1200 may further have a control panel with switches and LEDs to control the number of lights. The LEDs in the panel may indicate states or lights (on, off, status, etc.). The illuminator 1200 of the device of the present invention may be integrated with other conventional visual/functional lights. These physical controls may also allow control over these lights. The physical controls may vary depending on the application of the fixture. In applications where the fixture 1200 is permanently mounted in a space, the controls may be integrated into the facility infrastructure. In standalone portable applications, the controls may be fully integrated into the illuminator 1200, thereby having an integrated power supply with power level indicators and a graphic user interface display as well as a control panel.

[0082] The illuminator 1200 can communicate (1904) to facility and equipment managers and operators. Information can be accessed by a smart phone application 1906, a web interface on a laptop 1908 or a desktop 1908. The illuminator 1200 can transmit information to the site and the operator can retrieve information from the illuminator 1200. The wireless interface can be customized to meet the needs of various users. The illuminator 1200 can communicate about its output level, its energy consumption level, the internal temperature, the life cycle/time of use of the bulb 900, when it will need to be replaced, and the illuminator 1200 can work in combination with motion detection to determine if there is a high amount of bacteria in the space set up inside. The operator can further control the level of output of the illuminator 1200 and can manage a schedule of operating profiles that can be customized to best sanitize the area and optimize energy consumption.

[0083] The luminaire 1200 can communicate its status to the public or occupants of the space. Information can be accessed by a smart phone 1906 application, a web interface on a laptop 1908 or a desktop 1908, reassuring occupants that the space is sanitized. Additionally, information can be displayed on an information display within the space.

[0084] FIG. 20 shows several power pulse trains used to drive an excimer bulb, showing the difference between a 10,000 volt sine wave 2002 power and a 10,000 volt pulsed wave 2006 power. Only the upper voltages between 9,000 and 10,000 volts, shown in the left hand region, create usable light. Any voltage below 9,000 volts simply produces heat, which minimizes the power level possible when driving the bulb. The dark area 2004 between the outline of the sine wave and the white area in the center is all wasted power that is turned into heat generated inside the bulb and not output as light. There is no wasted voltage in this example pulsed wave power supply. The device 1200 of the present invention ideally uses pulsed wave power 2006 in its power supply 1204. This increases the efficiency of the bulb by 50-100% compared to existing sine wave based UV-C fixtures. It is also possible to reduce the voltage of the pulse wave 2006 below 10,000 volts to reduce the output of the bulb 800. The voltage range based on the graph presented is 100% at 10,000V and 0% at 9,000V, which is a very narrow voltage range that needs to be corrected and controlled.

[0085] FIG. 21 shows a power pulse train 2100 for driving an excimer bulb, where pulse wave 2102 is at 100%, pulse wave 2104 is at 50% to reduce the illumination using a symmetrical pattern by reducing every other wave, and pulse wave 2406 is at 50% to reduce the illumination using an asymmetrical pattern. The power supply can simply remove individual pulses to reduce the brightness. The pulses are so fast that even small dropouts between 10k Hertz and 250k Hertz are not evident and even at 100% the amount of visible light produced is negligible. A smart power supply has a microprocessor that removes some of these pulses to reduce the output of the fixture to any level below 1%. This technology is well known to those skilled in the art. These graphs are merely examples and the actual voltages will vary depending on the bulb design and internal gas composition.

[0086] FIG. 22 shows a side view of a system 2200 depicting an excimer bulb 800 with variable focus. The bulb 800 is positioned in the light path 2202, and a quartz lens 2204 has light wave shaping power. The lens 2204 may be circular, symmetrical, or linear to best fit the initial light path 2202. Additionally, the lens 2204 may be continuous or a Fresnel with steps. The lens 2204 may be moved closer to or farther from the excimer bulb 800, thereby changing the focus and increasing or decreasing the beam angle of the final emitted light 2206. This drawing is simplified and does not show filters or mirrors or other mechanical components as described above to simplify the relationship of the bulb to the lens.

[0087] FIG. 23 shows a liquid-cooled high power excimer bulb 2300. The excimer bulb 2300 is made up of an outer envelope 2302 and an inner envelope, where the outer envelope 2302 is shorter and the inner envelope 2304 is longer, and the outer envelope 2302 and the inner envelope 2304 are connected by two end caps 2306 that are heat welded together. The area between the inner and outer has a fill point 2308 on one of the end caps 2306. The fill point 2308 is similar to the fill points on existing excimer bulbs, and this form of chamber 2318 between the two envelopes is vented for filling with the appropriate excimer gas via the fill point 2308. The outer wall 2310 of the outer envelope 2304 has a conductive grid 2312 attached to it, and is the negative pole that extends around the entire circumference of the tube 2304. Similarly, the inner wall 2314 of the inner tube 2304 has a conductive grid 2316 extending around its inner circumference, making it the positive pole. Light is emitted uniformly in all directions outward from this type of bulb.

[0088] FIG. 24 shows a block diagram of a liquid cooled light bulb 2300 with a coolant system resulting in a high power excimer fixture 2400. The light bulb 2300 has a tube 2412 connected to an input 2402 that is connected to the output of a pump 2404. The input of the pump is connected to a return loop 2406 of tubing that extends around to the output 2408 of the light bulb 2300. Inside the tube 2406 and pump 2404 and inner wall 2316 is a single phase dielectric liquid that is circulated using the pump 2404. This dielectric liquid 2410 is typically used in large data centers where entire servers are submerged in a container to cool the server components. The liquid 2410 conducts heat very well but is not electrically conductive, a very important property for the device 2400 of the present invention. The liquid 2410 contacts the 10,000 volt conductive mesh 2316 of the bulb 2300. Heat is generated inside 2318 of the bulb 2300 and pumped out by the pump 2404 where it is dissipated to the environment as it travels through the feedback loop 2406 before re-entering the pump 2404 where the recirculation continues. The feedback loop 2406 may have a separate cooling device 2406 similar to those used in the computer cooling industry and is well known to those skilled in the art. A power supply 2414 is connected to the bulb 2300 using a negative wire 2416 which is connected to the exterior mesh 2312. The power supply 2414 is further connected to the bulb 2300 using a positive wire 2418 which is connected to the interior mesh 2316 and contacts the coolant 2410. The coolant 2410 allows significantly more power to be delivered to the bulb 2300, making it possible to use an incompatible and powerful excimer fixture 2400.

[0089] It will be understood that the terms "including," "comprising," and "consisting" and grammatical variations thereof do not exclude the addition of one or more components, features, steps, or wholes or groups thereof, and that these terms are to be construed as explicitly indicating components, features, steps, or wholes.

[0090] When the specification or claims refer to an "additional" element, this does not exclude the presence of more than one of the additional element.

[0091] When a claim or specification refers to "a (element)" or "an (element)," it is understood that such a reference is not to be construed as indicating that there is only one of that element.

[0092] When the specification states that a component, feature, structure, or characteristic "may," "might," "can," or "could" be included, it will be understood that it is not required that the particular component, feature, structure, or characteristic be included.

[0093] Although state diagrams, flow diagrams, or both may be used where applicable to describe an embodiment, the invention is not limited to only these diagrams and corresponding descriptions. For example, the flow need not move through each illustrated box or state, nor in the exact same order as shown and described.

[0094] The methods of the present invention may be implemented by performing or completing selected steps or tasks manually, automatically, or a combination thereof.

[0095] The term "method" may refer to methods, means, techniques, and procedures for accomplishing a given task, including, but not limited to, methods, means, techniques, and procedures known by a person skilled in the art to which the invention pertains or that are readily developed from known methods, means, techniques, and procedures by a person skilled in the art.

[0096] The term "at least" before a number may be used herein to indicate the beginning of a range beginning with that number (which may have an upper limit or no upper limit depending on a defined variation). For example, "at least 1" means 1, or 2 or more. The term "up to" before a number may be used herein to indicate the end of a range ending with that number (which may have a lower limit of 1 or 0, or may have no lower limit depending on a defined variation). For example, "up to 4" means 4, or less than 4, and "up to 40%" means 40%, or less than 40%. Approximate terms (e.g., "about," "substantially," "approximately," etc.) should be interpreted according to their ordinary and customary meanings used in the relevant technical field unless otherwise specified. In the absence of specific definitions and ordinary and customary usage in the relevant art, these terms should be interpreted as ±10% of the nominal value.

[0097] When a range is given in this document as "from (first number) to (second number)" or "from (first number) to (second number)," this means a range with a lower limit that is the first number and an upper limit that is the second number. For example, 25 to 100 should be interpreted as meaning a range with a lower limit that is 25 and an upper limit that is 100. In addition, it should be noted that when a range is given, unless otherwise stated, all possible subranges or intervals within this range are specifically contemplated. For example, when a range of 25 to 100 is given herein, this range is also intended to include subranges such as 26 to 100, 27 to 100, etc., 25 to 99, 25 to 98, etc., as well as any other possible combinations of lower and upper limits within the stated range (e.g., 33 to 47, 60 to 97, 41 to 45, 28 to 96, etc.). Please note that integer range values are used in this paragraph for illustrative purposes only, and unless otherwise specified, it should be understood that decimal and fractional values (e.g., 46.7 to 91.3) are also intended as endpoints of possible subranges.

[0098] When reference is made herein to a method including two or more predetermined steps, it should be noted that the predetermined steps may be performed in any order or simultaneously (unless the context precludes this possibility), and the method may further include one or more other steps performed before any of the predetermined steps, between two of the predetermined steps, or after all of the predetermined steps (unless the context precludes this possibility).

[0099] Thus, the present invention is well adapted to carry out the objects and attain the ends and advantages set forth above, as well as those inherent therein. While this disclosure has described presently preferred embodiments, many variations and modifications will become apparent to those skilled in the art. Such variations and modifications are encompassed within the spirit of the invention as defined by the appended claims.

Claims (6)

1. An excimer device comprising:
Krypton/chloride bulbs and
A band pass filter;
Diffusion layer and
Equipped with
the krypton/chloride bulb is configured to emit a beam of far UV-C light through the filter and then through the diffusing layer into an occupyable space;
The excimer instrument, wherein the diffusing layer is configured to diffuse the beam of far UV-C light. The excimer device of claim 1 , wherein the diffusing layer has a textured surface. 10. The excimer instrument of claim 1 comprising an illuminator element having a white LED. The excimer instrument of claim 1 comprising a plurality of filters. 10. The excimer instrument of claim 1, wherein the filter is configured to block wavelengths longer than 234 nm such that the excimer instrument does not substantially emit far UV-C emission wavelengths longer than 234 nm. 10. The excimer instrument of claim 1, comprising an intensity sensor.