JP2024067260A - Excimer lamps, ozone generators and ultraviolet irradiation devices - Google Patents

Abstract

[Problem] To provide a lamp capable of suppressing the generation of harmful gases such as nitrogen oxides and effectively performing ultraviolet irradiation and ozone generation, or an ozone generator or ultraviolet irradiation device equipped with such a lamp. [Solution] An excimer lamp 10 comprises a discharge vessel 20 formed by welding an inner tube 30 and an outer tube 40, into which an electrode 50 is inserted, and a tubular portion 60, with insulating covers 70, 80 attached to both ends of the tubular portion 60. A discharge space 20S is formed within the discharge vessel 20, and an internal space 10S, i.e., a flow path R, is formed within the tubular portion 60 around the discharge vessel 20. An isolated space 60S is formed between the tubular portion 60 and the discharge vessel 20 as a non-discharge space region. [Selected Figure] Figure 1

Description

The present invention relates to an excimer lamp that irradiates ultraviolet light, as well as an ultraviolet light irradiation device and an ozone generating device that generates ozone by irradiating ultraviolet light.

Discharge lamps that emit ultraviolet light can be used as light sources for sterilization and deodorization processes, and are also used as light sources for ultraviolet light irradiation devices that perform sterilization and deodorization, or as ozone generators that generate ozone that is used for sterilization and deodorization. Such lamps are installed in flow pipes through which gases, liquids, etc. to be sterilized and deodorized flow.

For example, an ozone generator is known that flows gas along the partition of a discharge tube that generates a glow discharge (see Patent Document 1). In this device, a tubular counter electrode is provided with a small gap between the wall of the discharge tube. Gas is then flowed through this small gap to generate ozone, and a mixed gas containing ozone is discharged. Another ozone generator is known that generates a silent discharge between the discharge tube and the tubular counter electrode, and converts ozone into ozone using ultraviolet light emitted from the discharge tube (see Patent Document 2).

Japanese Patent Application Laid-Open No. 57-111206 Japanese Patent Application Laid-Open No. 4-108603

In the above-mentioned Patent Document 1, there is only a small gap between the discharge tube and the counter electrode, and the arrangement is not substantially spaced apart, so corona discharge occurs in the gap. Therefore, when gas such as air flows, nitrogen oxides are generated, which may affect the objects to be treated, such as sterilization and deodorization, in some cases. In the above-mentioned Patent Document 2, a silent discharge occurs between the discharge tube and the counter electrode, so nitrogen oxides are generated. Nitrogen oxides reduce ozone and atomic oxygen, leading to a decrease in ozone concentration and a decrease in ozone generation efficiency. Nitrogen oxides eventually become dinitrogen pentoxide (N ₂ O ₅ ) and become stable, but react with moisture in the air to generate nitric acid (HNO ₃ ), which corrodes metals.

Therefore, there is a demand for a lamp that can effectively perform ultraviolet irradiation and ozone generation while suppressing the generation of harmful gases such as nitrogen oxides, or an ozone generator or ultraviolet irradiation device equipped with such a lamp.

The excimer lamp according to one aspect of the present invention comprises a discharge vessel in which at least a portion of the electrodes are disposed and in which a discharge gas is sealed, and a conductive tubular part disposed coaxially with the discharge vessel and spaced apart. The tubular part can have a variety of configurations, and can be configured as a pipe through which liquid, gas, etc. can flow. In addition, cylindrical vessels and outer casings are also included in the tubular part.

In the present invention, when a voltage is applied between the electrode and the tubular portion, no discharge occurs in the isolated space formed between the discharge vessel and the tubular portion, and ultraviolet rays are emitted toward the tubular portion by the discharge that occurs in the discharge space inside the discharge vessel. For example, the radial distance between the discharge vessel and the tubular portion is set to a distance at which no discharge occurs in the isolated space when a voltage is applied between the electrode and the tubular portion, but a discharge occurs inside the discharge vessel.

The radial distance between the discharge vessel and the tubular portion can be determined according to the size, thickness, etc. of the discharge vessel and the tubular portion. For example, the radial distance between the discharge vessel and the tubular portion can be set to be greater than 1 mm and equal to or less than 6 mm. In addition, the radial thickness of the tubular portion can be set to be in the range of 1 mm to 3 mm.

It is possible to use ultraviolet light with various peak wavelengths, and the size and thickness of the discharge vessel and tubular portion can be determined accordingly. For example, when emitting ultraviolet light with a peak wavelength of 172 nm, the radial distance between the discharge vessel and the tubular portion can be determined so as to be equal to or less than the transmission distance at which the ultraviolet light intensity ratio of the ultraviolet light with a peak wavelength of 172 nm emitted from the outer surface of the discharge vessel attenuates to 20%.

The discharge vessel can be configured in various ways. For example, it can be formed by welding at least one end of the outer tube to the inner tube. In this case, the electrode can be configured so that it is covered by the inner tube and is not exposed to the discharge space. For example, it is possible to configure a cylindrical electrode that is inserted into the inner tube. Alternatively, it is also possible to configure it so that the electrode is exposed without providing an inner tube.

For various variations of discharge vessels, the discharge vessel can be configured so that the inner diameter of the discharge space is larger than the radial distance of the discharge space. Here, the "inner diameter of the discharge space" refers to, for example, the inner tube size (outer diameter) if an inner tube is provided, or the electrode end (outer diameter) that is farthest from the center of the lamp axis along the radial direction of the electrode in the case of an exposed electrode.

When the electrode is cylindrical, it is possible to configure the electrode so that the radial distance between the outer peripheral surface of the electrode and the inner peripheral surface of the tubular portion is constant at least along the axial direction, out of the circumferential and axial directions.

The excimer lamp described above can be applied to an ozone generator, an ozone water generator equipped with an ozone generator, and an ultraviolet irradiation device. In another aspect of the ozone generator of the present invention, at least a portion of the isolated space forms a flow path through which a fluid containing oxygen flows. In another aspect of the ultraviolet irradiation device of the present invention, at least a portion of the isolated space forms a flow path through which a fluid flows.

The present invention provides a lamp that can effectively perform ultraviolet irradiation and ozone generation while suppressing the generation of harmful gases such as nitrogen oxides, or an ozone generator or ultraviolet irradiation device equipped with such a lamp.

1 is a schematic cross-sectional view of an excimer lamp according to a first embodiment. FIG. 1 is a schematic cross-sectional view of an excimer lamp according to a second embodiment. FIG. 11 is a schematic cross-sectional view of an excimer lamp according to a third embodiment. FIG. 13 is a schematic cross-sectional view of an excimer lamp according to a fourth embodiment.

Below, an embodiment of the present invention will be described with reference to the drawings.

Figure 1 is a schematic cross-sectional view of a first embodiment of an excimer lamp.

The excimer lamp 10 includes a discharge vessel 20. Here, the discharge vessel 20 is formed by fusing an inner tube 30 made of quartz glass to one end of an outer tube 40. The inner tube 30 and the outer tube 40 have a circular cross section, and the inner tube 30 is arranged coaxially with the outer tube 40 (with respect to the lamp axis C). A part of the inner tube 30 protrudes from one end 40T1 of the outer tube 40. An electrode 50 is also provided within the inner tube 30.

The electrode 50 is configured here as a conductive cylindrical electrode, and is inserted with a portion of it covered by the inner tube 30, and is arranged coaxially with the inner tube 30. One end of the electrode 50 protrudes from the end 30T of the inner tube 30 and is exposed to the outside, and is connected to a power supply unit (not shown) via a power supply line (not shown).

The electrode 50 may be made of any conductive material, and in this example, is made of a lightweight metal with good thermal conductivity, such as aluminum. For example, the electrode 50 can be formed into a cylindrical shape by bending a flat plate material.

Between the outer tube 40 and the inner tube 30, a discharge space 20S is formed in which a discharge gas is sealed. The discharge gas may be any gas capable of emitting ultraviolet rays when the lamp is lit. It is possible to seal in a rare gas or a discharge gas containing a rare gas. Here, xenon gas is sealed in.

In this embodiment, the discharge vessel 20 is configured as a discharge tube in which the outer diameter D of the inner tube 30 is relatively large (hereinafter, referred to as a large-diameter discharge tube, as necessary). Specifically, the outer diameter D of the inner tube 30, i.e., the inner diameter of the discharge space 20S, is configured to be larger than the radial distance d between the inner surface of the outer tube 40 and the outer surface of the inner tube 30, i.e., the discharge distance along the radial direction with respect to the lamp axis.

For example, it is possible to configure the inner tube 30 and the outer tube 40 with an inner diameter of 27 mm and an outer diameter of 30 mm, and the inner tube 30 with an inner diameter of 10 mm and an outer diameter of 13 mm, and the radial distance d between the inner surface of the outer tube 40 and the outer surface of the inner tube 30 can be set to 7 mm. In addition, the cylindrical electrode 50 can be a cylindrical electrode with an inner diameter of 4 mm and an outer diameter of 10 mm.

The excimer lamp 10 has a conductive tubular portion 60 that covers the discharge vessel 20 and is arranged coaxially with the discharge vessel 20. The tubular portion 60 is configured as a pipe for flowing raw material gas between the discharge vessel 20 and the discharge vessel 20, and is formed in a cylindrical shape here. The tubular portion 60 may be made of any conductive material, and in this case is made of a lightweight metal with good thermal conductivity such as aluminum. The tubular portion 60 is connected to earth or to a power supply via a power supply line (not shown).

Lids (caps) 70, 80 are attached to both ends 60T1, 60T2 of the tubular portion 60 to close the internal space of the tubular portion 60 that houses the discharge vessel 20. The disk-shaped lids 70, 80 are made of an insulating material (such as polyvinyl chloride (PVC)) and are fixed in place by being fitted into both ends 60T1, 60T2 of the tubular portion 60.

The lid 70, which is disposed on one end 40T1 side of the outer tube 40, has a hole 70A through which the inner tube 30 is inserted, and functions as a holding member that supports the inner tube 30. Disk-shaped light shielding plates 90A, 90B that block ultraviolet rays are installed on the surface of the inner space side of the lids 70, 80. Note that the inner tube 30 protruding from the lid 70 may be configured to have a joint such as a bore-through connector.

The excimer lamp 10 employs a lamp structure in which the discharge vessel 20 and tubular portion 60 are arranged coaxially with respect to the lamp axis C, and which forms an internal space 10S, which is a flow path R, inside the lamp. That is, the internal space 10S (flow path R) is formed by the tubular portion 60, the discharge vessel 20, and the lids 70 and 80, and an inlet 92 and an outlet 94 are formed in the lids 70 and 80, respectively. The axial length of the tubular portion 60 is longer than the axial length of the internal space 10S.

Therefore, gas or liquid can be made to flow into the internal space 10S (flow path R) of the excimer lamp 10 through the inlet 92 connected to a flow path pipe (not shown) and can be made to flow out from the outlet 94. Here, it is configured so that a raw material gas (e.g., air) containing oxygen flows in.

The inlet portion 92A of the inlet 92 through which the raw material gas flows into the internal space 10S is located at a position away from the lamp axis C in the lamp radial direction, and is formed to face the vicinity of the surface 40M extending along the radial direction of the outer tube 40 (discharge vessel 20). The gas that flows into the flow path R passes through the space (hereinafter referred to as the isolated space) 60S interposed between the tubular portion 60 and the discharge vessel 20, and the gas containing the ozone generated in the internal space 10S flows out from the outlet portion 94A of the outlet 94.

The outlet 94 is formed near the center of the lid 80 disposed on one end 40T2 side of the outer tube 40. Therefore, the inlet portion 92A of the inlet 92 and the outlet portion 94A of the outlet 94 are not positioned opposite each other along the lamp axis C (coaxial positional relationship), but are formed at different positions along the lamp radial direction.

Part of the gas that flows in from the inlet portion 92A of the inlet 92 hits the surface of one end 40T1 of the outer tube 40, and flows through the relatively narrow isolated space 60S. It then flows out from the outlet portion 94A, which does not face the inlet portion 92A. Therefore, the gas passing through the internal space 10S (flow path R) of the excimer lamp 10 flows in a generally turbulent state.

In this embodiment, when a high-frequency voltage is applied between the electrode 50 and the tubular portion 60 during lamp lighting, a discharge occurs within the discharge vessel 20, and excimer light is emitted as ultraviolet light. Here, xenon gas is sealed in as the discharge gas, so ultraviolet light with a peak wavelength of 172 nm is emitted. The frequency (MHz) and applied voltage (kV (peak to peak)) are appropriately determined according to the size of the discharge vessel 20 and the tubular portion 60, the amount of ozone generated, etc.

As described above, the discharge vessel 20 is configured as a large-diameter discharge tube. Therefore, even though the area of the outer surface 40M of the discharge vessel 20 (outer tube 40) that serves as the ultraviolet radiation surface is large, a discharge can be generated within the discharge vessel 20 at an applied voltage (discharge start voltage) that is relatively lower than that of the isolated space 60S, and ultraviolet rays can be uniformly irradiated to the isolated space 60S along the lamp axis C.

Here, the isolated space 60S along the lamp axis C is configured as a spatial region (non-discharge spatial region) where no corona discharge occurs, even when a discharge occurs in the discharge vessel 20 while the lamp is lit. The radial distance K between the inner surface of the tubular portion 60 and the outer surface 40M along the lamp axis of the discharge vessel 20 (outer tube 40), and the thickness 60T of the tubular portion 60 are determined so that the isolated space 60S becomes a non-discharge spatial region, even when a discharge occurs in the discharge vessel 20.

The ultraviolet rays emitted from the discharge generated in the discharge vessel 20 irradiate the raw material gas in the flow path R, including the isolated space 60S. As a result, the isolated space 60S becomes an ultraviolet ray irradiation area and an ozone generation area, ozone is generated from the oxygen contained in the raw material gas, and gas containing ozone flows out from the excimer lamp 10.

As described above, because the discharge vessel 20 is configured as a large-diameter discharge tube, ozone can be effectively generated in the ozone generation region, which is sufficiently secured as a spatial region, even with a relatively low power. On the other hand, because the isolated space 60S is formed as a non-discharge spatial region, even if nitrogen is contained in the raw material gas, the outflow gas containing ozone does not contain harmful gases such as nitrogen oxides.

In this embodiment, the excimer lamp 10 is configured as both a light source and an ozone generating source, and is incorporated into the ozone water generator. Specifically, the outlet 94 of the excimer lamp 10 is connected to the gas-liquid mixer 13 via a pipe 12. The gas containing ozone is mixed with a liquid such as water in the gas-liquid mixer 13 to generate ozone water. Note that the ozone water generator includes an ozone decomposition section, a dehumidification section, a flow rate adjustment section, etc., as described in, for example, Japanese Patent Application Laid-Open Publication No. 11-347567, and the configuration related to the mechanism and ozone water generation process is well known, so a description thereof will be omitted.

As described above, the excimer lamp 10 in this embodiment does not employ an electrode structure in which an outer electrode is provided on the outer surface 40M of the discharge vessel 20 (outer tube 40) as in conventional excimer lamps. Instead, a voltage is applied between the electrode 50 and the tubular portion 60 (not the outer electrode), which is configured as a pipe for flowing the raw material gas, to irradiate ultraviolet light into the isolated space 60S through which the raw material gas flows.

Since there is no external electrode that would be an obstacle to UV irradiation or the flow of the raw gas, UV rays can be effectively irradiated onto the raw gas, and ozone can be efficiently generated. In addition, since no corona discharge occurs in the isolated space 60S, nitrogen oxides and the like are not produced, and ozone can be generated without affecting the equipment, instruments, or objects to be sterilized and deodorized through which the gas passes.

In particular, with regard to suppressing the occurrence of corona discharge, since the electrode 50 and the tubular portion 60 are configured to be coaxially arranged as cylindrical conductive members, the radial distance between the outer peripheral surface of the electrode 50 and the inner peripheral surface of the tubular portion 60 is constant along the circumferential and axial directions. As a result, when a voltage that generates a discharge is applied within the discharge vessel 20, a uniform distribution of electric field strength is formed between the inner surface of the electrode 50 and the inner surface of the tubular portion 60 along the circumferential and axial directions.

Therefore, unlike conventional excimer lamps, corona discharge due to electric field concentration near the opening of the outer electrode does not occur. In addition, because the discharge vessel 20 is configured as a large-diameter discharge tube, the diameter (curvature) of the electrode 50 and tubular portion 60 is relatively large, and ultraviolet radiation is closer to surface irradiation than in conventional excimer lamps. This structure suppresses the occurrence of corona discharge due to electric field concentration in the isolated space 60S.

The tubular section 60, which is connected to the earth connection or the power supply, is configured as a pipe for flowing the raw material gas. Therefore, it can be easily attached and detached to an ultraviolet irradiation device, an ozone generation device, etc., and can be easily replaced. It can also be easily configured as a lamp module with an integrated power supply, and lamp replacement can be easily performed without the need to remove only the discharge vessel (lamp) made of quartz glass.

In addition, the piping structure of the tubular portion 60 makes it possible to use various conductive materials under conditions that allow the application of a voltage that generates a discharge. Therefore, by constructing the tubular portion 60 from a lightweight material with high thermal conductivity, such as aluminum, and exposing it to the isolated space 60S, it is possible to provide an excimer lamp 10 that has improved heat dissipation and is lightweight.

On the other hand, both ends of the tubular portion 60 are connected to the lids 70 and 80, which are insulating members, and the inlet 92 and outlet 94 are formed on the insulating lids 70 and 80, which can be easily deformed. This makes it possible to freely design the paths of the inlet 92 and outlet 94 and the flow of gas in the flow path R.

Furthermore, the gas that flows into the internal space 10S (flow path R) of the excimer lamp 10 flows out in a turbulent state as described above. Therefore, the gas is sufficiently irradiated with ultraviolet light while passing through the internal space 10S (flow path R) of the excimer lamp 10, and ozone can be generated effectively. In addition, since the axial length of the tubular portion 60, which has high heat dissipation properties, is longer than the axial length of the discharge space 20S (outer tube 40), it is possible to sufficiently cool the entire internal space 10S (flow path R).

The configuration of the electrode 50 and the tubular portion 60, the radial distance K, and the thickness 60T of the tubular portion 60 may be determined so that no discharge occurs in the isolated space 60S, and may be determined taking into consideration the distance over which ultraviolet light attenuates (the transmission distance). The radial distance K may be determined so that at least no corona discharge occurs.

For example, if the radial distance K is 1 mm or less, the isolated space 60S exists as a small gap, which is essentially the same as if the tubular portion 60 were fitted into the discharge vessel 20 (outer tube 40), and corona discharge inevitably occurs in the small gap.

In addition, because the isolated space 60S in which ozone is generated is small, the ultraviolet rays emitted from the discharge vessel 20 are blocked by the tubular portion 60 in a distance range where the ultraviolet illuminance is high, and the raw material gas is not sufficiently irradiated with ultraviolet rays, resulting in poor ozone generation efficiency. In addition, if the isolated space 60S is small, the tubular portion 60 itself becomes an obstacle that impedes the flow of the raw material gas, making it impossible to flow the raw material gas efficiently. Therefore, in order to prevent the occurrence of corona discharge in the isolated space 60S and to increase the efficiency of ozone generation, it is preferable to set the radial distance K to be greater than 1 mm.

On the other hand, when ultraviolet rays with a peak wavelength of 172 nm are radiated into the atmosphere, it is known that the ultraviolet intensity attenuates to about 10% at about 8 mm. Therefore, it is preferable to set the radial distance K so that it is equal to or less than the transmission distance at which the ultraviolet intensity ratio of the ultraviolet rays radiated from the outer surface 40M of the discharge vessel 20 (outer tube 40) attenuates to 20%, and to reduce the proportion of the flow of raw material gas that flows through areas with low ultraviolet illuminance. For example, the radial distance K can be set to 6 mm or less.

In addition, if the radial distance K is relatively long, the applied voltage that contributes to the discharge in the discharge vessel 20 decreases, and the ultraviolet illuminance decreases. Therefore, when emitting ultraviolet light with a peak wavelength of 172 nm, it is preferable to set the radial distance K in the range of 2 mm to 3 mm.

It is preferable that the insulating covers 70, 80 provided near both ends of the tubular section 60 are formed in positions that do not affect the distribution of electric field strength. In addition, it is preferable that the inner surface of the tubular section 60 exposed to the isolated space 60S is not provided with an uneven shape that would cause electric field concentration, but rather is formed in a smooth shape that does not cause electric field concentration.

The thickness 60T of the tubular portion 60 can be determined by taking into consideration the heat dissipation properties of the outer surface of the tubular portion 60, i.e., the suppression of temperature rise in the isolated space 60S, which leads to the suppression of ozone thermal decomposition, as well as the rigidity and weight. For example, the thickness 60T of the tubular portion 60 can be determined in the range of 1 mm to 3 mm.

Next, we will explain the second embodiment of the excimer lamp. In the second embodiment, the excimer lamp is configured with the inlet portion of the inlet and the outlet portion of the outlet formed along the radial direction.

Figure 2 is a schematic cross-sectional view of an excimer lamp according to a second embodiment. The excimer lamp 100 comprises a discharge vessel 120 formed by welding an inner tube 130 and an outer tube 140, into which an electrode 150 is inserted, and a tubular portion 160, with insulating lids 170 and 180 attached to both ends of the tubular portion 160. The lid 170 is provided with a joint (here, a bore-through connector) 190 that supports the inner tube 130.

A discharge space 120S is formed within the discharge vessel 120, and an internal space 10S, i.e., a flow path R, is formed around the discharge vessel 120 within the tubular portion 160. An isolation space 160S is formed between the tubular portion 160 and the discharge vessel 120.

The axial length of the tubular portion 160 is shorter than the axial length of the discharge vessel 120 (outer tube 140). Parts of the lids 170 and 180 extend to a position opposite the discharge vessel 120, and function as part of the piping through which the raw material gas flows. The lids 170 and 180 have gas inlet ports 192 and outlet ports 194 formed in positions facing the ends of the discharge vessel 120. The inlet ports 192 and outlet ports 194 each face in the lamp radial direction.

As in the first embodiment, the isolated space 160S is formed to be a non-discharge space region. Therefore, it is possible to allow gas containing ozone to flow out of the excimer lamp 100 while suppressing the generation of harmful gases such as nitrogen oxides. Also, since the inlet 192 and outlet 194 are formed in positions facing the outer surface along the lamp axis near both ends of the discharge vessel 120, it is possible to adopt a lamp structure in which the gas is in a turbulent state in the flow path R, as in the first embodiment, and ultraviolet rays can be sufficiently irradiated.

Next, an excimer lamp according to a third embodiment will be described with reference to FIG. 3. In the third embodiment, the inlet and outlet are formed in a conductive tubular portion. The rest of the configuration is substantially the same as that of the second embodiment.

Figure 3 is a schematic cross-sectional view of an excimer lamp according to a third embodiment. The excimer lamp 200 comprises a discharge vessel 220 formed by welding an inner tube 230, into which an electrode 250 is inserted, and an outer tube 240, and a tubular portion 260. The tubular portion 260 here is a bottomed tube, and an insulating lid 290 is attached to one end of the tubular portion 260. Note that instead of the lid 290, a joint (here, a bore-through connector) 190 that axially supports the inner tube 230 may be provided.

A discharge space 220S is formed within the discharge vessel 220, and an internal space 210S, i.e., a flow path R, is formed within the tubular portion 260 around the discharge vessel 220. An isolated space 260S is formed between the tubular portion 260 and the discharge vessel 220. As in the first and second embodiments, the isolated space 260S is formed to be a non-discharge space region.

The tubular portion 260 is formed with an inlet 292 and an outlet 294. As in the second embodiment, the inlet 292 and the outlet 294 are formed in a direction facing the outer surface along the lamp axis near both ends of the discharge vessel 220 (outer tube 240). Note that the number of inlet 292 and outlet 294 is not limited to one, and it is possible to form more than one.

Next, a fourth embodiment of the excimer lamp will be described with reference to FIG. 4. In the fourth embodiment, the flow path is formed along the lamp axis.

Figure 4 is a schematic cross-sectional view of an excimer lamp according to a fourth embodiment. The excimer lamp 300 comprises a discharge vessel 320 formed by welding an inner tube 330 and an outer tube 340 into which an electrode 350 is inserted, and a tubular portion 360. As in the first and second embodiments, the tubular portion 360 is tubular without a bottom, and both ends are open.

A discharge space 320S is formed within the discharge vessel 320, and an internal space 310S, i.e., a flow path R, is formed around the discharge vessel 320 within the tubular portion 360. An isolation space 360S is formed between the tubular portion 360 and the discharge vessel 320.

In the first to fourth embodiments, the electrode is inserted into the inner tube, but the inner tube may be configured to have the electrode embedded therein, or a portion of the electrode may be exposed from the inner tube into the discharge vessel (discharge space). In this case, the cross-sectional shape of the discharge vessel and the cross-sectional shapes of the inner and outer tubes may be arbitrary, and may be, for example, rectangular, and are not limited to a coaxial arrangement. Furthermore, it is possible to configure the discharge vessel without providing an inner tube, and the shape, size, thickness, etc. of the discharge vessel and tubular portion may be determined within a range that allows the formation of an isolated space that serves as a non-discharge space relative to the tubular portion.

In the first to fourth embodiments, the excimer lamp is described as being mountable in an ozone water generator, but it can also be used as a light source for an ultraviolet irradiation device that performs sterilization and deodorization processes. Furthermore, by not passing gas or liquid through the tubular section and constructing the annular section from a material that transmits ultraviolet light, it can also be configured as an excimer lamp that radiates ultraviolet light toward the outside of the tubular section. It is also possible to configure the excimer lamp to radiate ultraviolet light with a wavelength other than 172 nm, and the thickness of the tubular section and the radial distance interval of the isolated space can be determined accordingly.

REFERENCE SIGNS LIST 10 Excimer lamp 20 Discharge vessel 30 Inner tube 40 Outer tube 50 Electrode 60 Tubular portion

Claims (11)

a discharge vessel in which at least a portion of the electrode is disposed and in which a discharge gas is sealed;
a conductive tubular portion disposed coaxially with the discharge vessel with a gap therebetween;
An excimer lamp characterized in that, when a voltage is applied between the electrode and the tubular portion, no discharge occurs in the isolated space formed between the discharge vessel and the tubular portion, and ultraviolet rays are radiated toward the tubular portion by a discharge generated in the discharge space within the discharge vessel. The excimer lamp according to claim 1, characterized in that the radial distance between the discharge vessel and the tubular portion is determined so that when a voltage is applied between the electrode and the tubular portion, no discharge occurs in the isolated space, but a discharge occurs within the discharge vessel. The excimer lamp of claim 1, characterized in that the radial distance between the discharge vessel and the tubular portion is greater than 1 mm and less than or equal to 6 mm. The excimer lamp according to claim 1, characterized in that the radial thickness of the tubular portion is set in the range of 1 mm to 3 mm. The excimer lamp of claim 1, characterized in that the radial distance between the discharge vessel and the tubular portion is equal to or less than the transmission distance at which the ultraviolet intensity ratio of ultraviolet light having a peak wavelength of 172 nm emitted from the outer surface of the discharge vessel attenuates to 20%. The excimer lamp of claim 1, characterized in that the inner diameter of the discharge space is set to be larger than the radial distance of the discharge space. the discharge vessel is formed by welding an outer tube and at least one end of an inner tube together;
2. The excimer lamp according to claim 1, wherein the electrodes are covered by the inner tube and are not exposed to the discharge space. The electrode is cylindrical,
2. The excimer lamp according to claim 1, wherein a radial distance between an outer peripheral surface of the electrode and an inner peripheral surface of the tubular portion is constant at least along the axial direction out of a circumferential direction and an axial direction. The excimer lamp according to any one of claims 1 to 8 is provided,
An ozone generating device, characterized in that at least a portion of the isolated space forms a flow path through which a fluid containing oxygen flows. An ozone water generator comprising the ozone generating device described in claim 9. The excimer lamp according to any one of claims 1 to 8 is provided,
13. An ultraviolet irradiation device, comprising: at least a portion of the isolated space forming a flow path through which a fluid flows.

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