JP2006185656A - Dielectric barrier discharge lamp and ultraviolet-ray irradiation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dielectric barrier discharge lamp which has prevented impurities scattered from an irradiated object from adhering to the surface of the dielectric barrier discharge lamp, and provide an ultraviolet-ray irradiation device using this. <P>SOLUTION: The dielectric barrier discharge lamp EXL is equipped with a slender tubular airtight container 1 made of an ultraviolet-ray transmitting material, excimer generating gas sealed into the airtight container, a long inner electrode 2 arranged and installed in the airtight container so as to form the dielectric barrier discharge in the airtight container over almost the whole length in its tube axial direction, the outer electrode OE which acts so as to generate the dielectric barrier discharge in the airtight container in collaboration with the inner electrode arranged and installed on the outer face of the airtight container, and an air flow generating means AB which forms air flow across a front part along the tube axial direction of the airtight container. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a dielectric barrier discharge lamp and an ultraviolet irradiation apparatus using the same.

Excimer discharge lamps, that is, dielectric barrier discharge lamps that generate silent near-monochromatic radiation by causing silent discharge, that is, dielectric barrier discharge, of rare gases such as xenon or rare gas halides are described in many literatures. It has been known for some time. In the dielectric barrier discharge, a pulsed current flows. Because this pulsed current has a high-speed electron flow and a long rest period, a substance that emits ultraviolet rays such as xenon temporarily binds to the molecular state (excimer state) and returns to the ground state. Efficiently emits short wavelength ultraviolet rays with little reabsorption. In the case of xenon, molecular light emission having a wide half-value width with a center wavelength of 172 nm is performed. The ultraviolet light having a wavelength of 172 nm has a higher energy than the ultraviolet light having a wavelength of 185 nm or 254 nm obtained from a low-pressure mercury lamp, and is larger than the binding energy of the organic compound to be decomposed. For this reason, by irradiating ultraviolet rays with a wavelength of 172 nm, the bond of the organic compound can be cut, decomposed and removed. Furthermore, by performing ultraviolet irradiation with a wavelength of 172 nm in the atmosphere, oxygen in the atmosphere is decomposed to generate active oxygen, and the organic compound whose bond is broken reacts with the active oxygen to generate carbon dioxide (CO _2). ), Water (H ₂ O), and the like are generated, so that the organic compound can be easily removed. Therefore, the dielectric barrier discharge lamp is extremely effective as an ultraviolet light source.

  As a dielectric barrier discharge lamp, a dielectric barrier discharge lamp that performs dielectric barrier discharge using an elongated tubular hermetic container is known (see Patent Document 1). The dielectric barrier discharge lamp described in Patent Document 1 forms an arc tube including an elongated hermetic vessel, an internal electrode extending in the axial direction in the hermetic vessel, and an excimer generation gas sealed in the hermetic vessel Then, an aluminum lamp body having a cooling function and recessed so that a part of the outer surface of the hermetic container fits is brought into contact with the outer surface of the hermetic container as an external electrode, along the tube axis direction of the hermetic container. And uniform dielectric barrier discharge, and the heat generated from the arc tube is quickly dissipated to keep the luminous efficiency high. Further, in order to bring the external electrode and the airtight container into close contact with each other, they are configured to be in pressure contact with each other.

When ultraviolet irradiation is performed using the above-described conventional dielectric barrier discharge lamp of this type, a longer dielectric barrier discharge lamp has been developed with an increase in the area of the object to be irradiated, and its effective length is 1 m. More than that came to be used. When such a long dielectric barrier discharge lamp is used, various industrial applications such as ashing of a large-area liquid crystal substrate, curing and sterilization of a photosensitive resin are possible.
Japanese Patent Laid-Open No. 2003-197152

  However, for example, when performing dry cleaning by irradiating the irradiated object with ultraviolet rays using a dielectric barrier discharge lamp, it may be generated in impurities or atmospheres attached to the irradiated object and scattered by the ultraviolet irradiation. Impurities that float in the atmosphere adhere to the surface of the dielectric barrier discharge lamp. As a result, there is a problem in that the amount of ultraviolet rays radiated from the dielectric barrier discharge lamp to the outside is reduced, and the illuminance of ultraviolet rays with respect to the irradiated object decreases with the passage of lighting time. Thus, when the ultraviolet illuminance decreases, it becomes difficult to obtain an ultraviolet irradiation effect such as a predetermined cleaning effect.

  An object of the present invention is to provide a dielectric barrier discharge lamp in which impurities scattered from an object to be irradiated are prevented from adhering to the surface of the dielectric barrier discharge lamp, and an ultraviolet irradiation apparatus using the dielectric barrier discharge lamp.

  The dielectric barrier discharge lamp according to the present invention includes an airtight container having an elongated tubular shape made of an ultraviolet light transmissive material; an excimer generating gas sealed in the airtight container; and a dielectric barrier discharge in the airtight container in the tube axis direction. A long internal electrode disposed so as to occur over substantially the entire length of the gas-tight container; disposed on the outer surface of the hermetic container along the axial direction of the tube, and generates a dielectric barrier discharge in the hermetic container in cooperation with the inner electrode. An external electrode that acts as such; and an airflow generating means that forms an airflow across the front surface portion along the tube axis direction of the hermetic container.

  In the present invention, by having the above-described configuration, even if impurities such as impurities adhering to the irradiated object or impurities floating in the atmosphere try to adhere to the dielectric barrier discharge lamp, Since it is blocked by the air flow formed across the front surface along the tube axis direction of the container, it does not adhere to the surface of the dielectric barrier discharge lamp. As a result, the adhesion of impurities on the surface of the dielectric barrier discharge lamp is prevented, so that the amount of ultraviolet radiation is effectively prevented from being reduced due to the adhesion of impurities, and the ultraviolet illuminance on the irradiated object is reduced to a required level over a long period of time. Can be maintained.

  According to the present invention, a dielectric barrier discharge lamp that effectively prevents impurities from adhering to the surface of the dielectric barrier discharge lamp and maintains the ultraviolet illuminance of the irradiated object at a required level over a long period of time, and the same An ultraviolet irradiation device using can be provided.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
[First embodiment]
1 to 4 show a first embodiment for carrying out a dielectric barrier discharge lamp according to the present invention, FIG. 1 is a partial sectional front view of the dielectric barrier discharge lamp, and FIG. 2 is a part of an arc tube. FIG. 3 is a partially cutaway / sectional front view showing a support part and a power feeding part of the arc tube, and FIG. 4 is a side sectional view. In this embodiment, the dielectric barrier discharge lamp EXL includes the hermetic container 1, the excimer forming gas, the internal electrode 2, the external electrode OE, and the airflow forming means AB, and is lit by being energized by the high frequency lighting circuit HFI. In addition, the airtight container 1, the excimer forming gas, and the internal electrode 2 constitute an arc tube LT that is assembled in advance and integrated.

  <About the arc tube LT> In this embodiment, the arc tube LT has a pair of power feeding portions 3A and 3B and a pair of support portions 5 and 5 at both ends in addition to the above configuration.

    (Regarding the airtight container 1) The airtight container 1 is made of an ultraviolet light transmissive material, and has an elongated discharge space 1a formed therein. For example, a structure in which both ends of an elongated tube are sealed and a cylindrical discharge space 1a is formed inside can be used. Further, as in a second embodiment to be described later, it is also possible to have a structure in which a cylindrical elongated discharge space 1a ′ is formed inside by sealing both ends of a double elongated tube. Generally, synthetic quartz glass is used as a material that transmits ultraviolet rays. However, in the present invention, any material may be used as long as it is transparent to ultraviolet rays having a wavelength to be used.

  Further, the airtight container 1 is a straight pipe excellent in linearity in order to allow a large number of dielectric barrier discharge lamps EXL to be arranged in parallel at relatively narrow intervals in order to secure a required amount of ultraviolet rays. Although it is preferable, it may be slightly curved. In practice, a slight curve is likely to occur when the elongated tube is formed. For example, a maximum of approximately 1 mm or less can be formed with respect to a total length of approximately 1200 mm. However, this degree of bending is allowed as being almost straight.

    (Excimer production gas) As the excimer production gas, one or a mixture of rare gases such as xenon (Xe), krypton (Kr), argon (Ar) or helium (He), or a rare gas halide such as XeCl is used. , KrCl, or the like can be used. When the rare gas halide is enclosed, the rare gas and a halogen such as fluorine (F), chlorine (Cl), bromine (Br) or iodine (I) are enclosed, and the halide is contained inside the hermetic vessel 1. It may be generated. In addition to the excimer-generating gas, mixing of a gas that does not generate excimer, such as neon (Ne), is allowed in some cases.

    (About Internal Electrode 2) The internal electrode 2 is disposed so as to face the external electrode OE across the wall surface of the airtight container 1. However, the internal electrode 2 may be either of an aspect sealed so as to be exposed in the discharge space 1a of the hermetic container 1 or an aspect disposed outside the discharge space 1a inside the hermetic container 1, for example. In the case of the latter mode, for example, the airtight container 1 has a double tube structure, and the internal electrode 2 is disposed along a cylindrical wall surface formed on the central axis side of the airtight container 1. Therefore, in the present invention, the internal electrode 2 should be understood to mean an electrode disposed relatively inside the airtight container 1 when the airtight container 1 is viewed from the outside.

  As can be understood from the above description, in the present invention, the internal electrode 2 is disposed inside the hermetic container 1 so as to generate a dielectric barrier discharge over almost the entire length in the tube axis direction, that is, the entire effective length of the lamp. As long as the electrode is provided, preferably an electrode that is long in the tube axis direction, the remainder may be any configuration. In FIG. 1, FIG. 3, and FIG. 4, the internal electrode 2 is not shown.

  A preferred configuration example of the internal electrode 2 shown in FIG. 2 will be described. That is, the internal electrode 2 has a mesh shape in which a large number of independent mesh portions 2b are dispersedly arranged in the axial direction of the hermetic container 1 and are respectively disposed around the air gaps. In addition, the structure is integrated and connected through the connecting portion 2 a, and is configured to be disposed in a state of being inserted into the airtight container 1. By using such an internal electrode 2, the amount of ultraviolet rays generated can be relatively increased. In addition, the mesh-like part 2b may be continuous with respect to the circumferential direction or may be divided.

  Therefore, in the present invention, when the internal electrode 2 has a mesh shape, the mesh portion 2b is specifically allowed to have a ring shape, a spiral shape, a coil shape, a mesh shape, or the like. The

  Next, a support structure and a power feeding structure when the internal electrode 2 is disposed inside the hermetic container 1 made of quartz glass will be described. In order to seal the internal electrode 2 in the hermetic container 1, as shown in FIG. 2, a sealing structure using a sealing metal foil 1b1 can be employed. That is, after linear ends 2c formed by extending both ends of the connecting portion 2a of the internal electrode 2 are connected to the sealing metal foil 1b1 by welding or the like, and the internal electrode 2 is inserted into the hermetic container 1, Then, the quartz glass at the end is heated to be softened and pinch-sealed from above the sealing metal foil 1b1. If it does so, the sealing part 1b will be formed in the edge part of the airtight container 1, and the internal electrode 2 will be supported by the predetermined position.

    (Power Supply Units 3A and 3B) The power supply units 3A and 3B constitute power supply terminals for supplying the internal electrode 2 with a current necessary for dielectric barrier discharge. The power feeding portions 3A and 3B are each formed in a rod shape, and the inner ends are welded to molybdenum foils 1b1 embedded in the sealing portions 1b formed at both ends of the airtight container 1, and the base ends are the airtight container 1's. It protrudes from the sealing part 1b formed at both ends in the direction of the external tube axis. In addition, the power feeding units 3A and 3B are caulked and connected to the power feeding line 4 inside a support unit 5 described later. The feeder line 4 extends from an output end of a high-frequency lighting circuit HFI described later.

    (Supporting part 5) As shown in FIG. 3, the supporting part 5 includes a bottomed cylindrical cap body 5a, a tightening ring 5b, and an attachment arm 5c. The cap body 5a surrounds the end of the arc tube LT. And it has the insertion hole 5a1 of the feeder 4 at the bottom. The tightening ring 5 b is disposed at the opening end of the cap body 5 a and is fixed to the end of the airtight container 1. The cap body 5a may be formed of either a metal or an insulator, and may be made of a metal whose inner surface is lined with an insulator if desired. The mounting arm 5c protrudes upward in the figure from the side surface of the cap body 5a, and the arc tube LT is illustrated using the mounting arm 5c with the upper surface of the cap body 5a contacting the positioning arm 8 shown in FIG. It is attached to the fixed part that does not. The positioning arm 8 extends from both ends of the external electrode OE in the tube axis direction toward the end of the hermetic container 1 and defines the mounting position of the arc tube LT and hence the hermetic container 1. The mounting arm 5c may be formed of either a metal or an insulator. If desired, the mounting arm 5c may have a structure in which an insulating material is interposed between the mounting arm and the mounting position. Then, the cap body 5a is made of an insulator or a metal lined with an insulator, the mounting arm 5c is insulated from the mounting position, or the positioning arm 8 itself or the arm 8 By insulating between the support portion 5 and the power supply portions 3A and 3B, corona discharge is generated between the power supply portions 3A and 3B, so that it is possible to suppress a reduction in ultraviolet radiation from the dielectric barrier discharge lamp.

  <Regarding External Electrode OE> The external electrode OE extends so as to be in close contact with the outer surface of the hermetic vessel 1 along the tube axis direction at least in the effective length portion of the lamp, or to maintain an appropriate gap. A dielectric barrier discharge that is disposed and faces the internal electrode 2 and that has at least one wall surface of the hermetic container 1 as a dielectric by the cooperation of the external electrode OE and the internal electrode 2 is discharged into the discharge space of the hermetic container 1. It acts to occur in 1a.

  Further, the external electrode OE may have either a configuration with rigidity or a configuration with flexibility. In the case of rigidity, the external electrode OE as shown in the figure formed in a block shape made of a conductive metal and having a large heat capacity is obtained. Therefore, a member conventionally referred to as a lamp can be used as it is as an external electrode if desired. In this case, there is no need to adopt a structure in which the conventionally used external electrode OE made of a thin aluminum plate is sandwiched between the lamp body and the airtight container 1. Further, in order to cool the portion of the hermetic container 1 in the region where the dielectric barrier discharge occurs, the cooling means 9 can be disposed on the external electrode OE. In this case, the cooling means 9 may have any configuration, but a cooling water passage through which the refrigerant flows is externally attached to the external electrode OE, or is integrally formed inside. Is preferred. Further, the external electrode OE may be in a continuous planar state or mesh state. The mesh shape means a mesh shape, a punching shape, a lattice shape, or the like.

  <Airflow generation means AB> The airflow generation means AB is a means for forming an airflow across the front surface portion of the airtight container 1 along the tube axis direction. The airflow formed may be any airflow as long as it is a clean gas such as an airflow using an atmosphere, for example, an airflow using an inert gas, regardless of the atmosphere. However, the airflow to be formed must have a speed and a flow rate that can prevent impurities from adhering to the surface of the hermetic container 1, particularly the portion facing the irradiated object.

  Further, the airflow generation means AB can be arranged in a one-to-one relationship with respect to the single arc tube LT. However, if desired, a single air flow generation means AB may be disposed as a common means for each dielectric barrier discharge lamp with respect to a plurality of arc tubes LT arranged in parallel.

  Further, the airflow generation means AB may be configured to be coupled to the arc tube LT or the external electrode OE of the dielectric barrier discharge lamp EXL, or may be configured to be separated. The latter is suitable for the configuration in which a single airflow generation means AB is provided for the plurality of arc tubes LT described above.

  Still further, the air flow generation means AB may have any of a gas blowing structure, a gas suction structure, or a configuration provided with a gas blowing structure and a gas suction structure. Further, a structure in which a long single gas blowing or gas suction structure is disposed along the tube axis of the hermetic container 1 or a plurality of gas blowing or gas suction structures is disposed along the tube axis of the hermetic container 1. It is allowed to have a structure etc.

  The illustrated air flow generating means AB extends the gas blowing pipe 10 in the longitudinal direction of the hermetic container 1 and, as shown in FIG. 4, a number of gas blowing holes on the side surface of the gas blowing pipe 10 facing the hermetic container 1. 11 are formed at appropriate intervals. Note that the gas blowing tube may be formed integrally with the external electrode OE. Further, an elongated gas blowing slit may be formed instead of the gas blowing hole. Furthermore, instead of extending the gas blowing pipe in the longitudinal direction of the hermetic container 1, a large number of gas blowing pipes may be arranged along the tube axis direction of the hermetic container 1. In this case, a large number of gas blowing pipes are arranged so as to be substantially orthogonal to the tube axis of the hermetic container 1.

  <High Frequency Lighting Circuit HFI> The high frequency lighting circuit HFI applies a high frequency voltage between the internal electrode 2 and the external electrode OE of the dielectric barrier discharge lamp EXL to energize the dielectric barrier discharge lamp EXL to light it. . The high-frequency lighting circuit HFI is mainly composed of a parallel inverter, and the high-frequency output of the high-frequency output is a pair of power supply portions of the arc tube LT in the dielectric barrier discharge lamp EXL via the power supply lines 4 and 4 on the high potential side. 3A and 3B and the low potential side are applied to the external electrode OE, respectively.

  <Operation of Dielectric Barrier Discharge Lamp EXL> In the dielectric barrier discharge lamp EXL, one of the high-frequency output terminals of the high-frequency lighting circuit HFI, for example, the high-voltage side output terminal is connected from the internal electrode 2 to the outside via the feeder lines 4 and 4. Since the low-voltage (ground) side output end is connected to one end of the external electrode OE, for example, the input power source (not shown) of the high-frequency lighting circuit HFI is turned on. A high frequency is generated, and the high frequency output is applied between the internal electrode 2 and the external electrode OE opposed to the internal electrode 2 through the wall surface of the airtight container 1. As a result, dielectric barrier discharge occurs inside the hermetic container 1. By this dielectric barrier discharge, vacuum ultraviolet light having a center wavelength of 172 nm is emitted by the xenon excimer. Since vacuum ultraviolet light permeate | transmits the wall surface of the airtight container 1, and is derived | led-out outside, this can be utilized according to each objective.

  Further, when the dielectric barrier discharge lamp EXL is turned on, the air flow crossing the hermetic container 1 is at least of the dielectric barrier discharge lamp EXL so that the air flow forming means AB is activated and passes the position near the lower surface in the figure of the hermetic container 1. Occurs throughout the effective length to form an air curtain. As a result, since the surface of the airtight container 1 is protected by the air curtain, the adhesion of impurities to the surface of the airtight container 1 is suppressed.

FIG. 5 is a graph showing the change of the ultraviolet illuminance with respect to the lighting time of the dielectric barrier discharge lamp in the first embodiment of the present invention together with that of the comparative example. In the figure, the horizontal axis indicates lighting, and the vertical axis indicates ultraviolet illuminance. In the figure, curve A is the present invention, curve B is a comparative example, and each curve is created based on acquired data up to about 3500 hours of lighting. The comparative example is a conventional technique having the same specifications as the present invention except that no airflow forming means is provided. The figure is created based on the data when the present invention and the comparative example are used in the dry cleaning process under the same conditions. The measurement conditions are those in which air with an air velocity of 3 m and 0.23 m ³ / sec is blown from a position 300 mm away from the side direction of the dielectric barrier discharge lamp EXL, and ultraviolet illuminance at an ultraviolet irradiation distance of 3 mm is measured. As can be understood from the figure on the surface of the dielectric barrier discharge lamp EXL, according to the present invention, since the adhesion of impurities is prevented, there is little decrease in ultraviolet illuminance even when the dielectric barrier discharge lamp is lit for a long time. . On the other hand, in the comparative example, the decrease in ultraviolet illuminance is significant due to the adhesion of impurities.
[Second form]
FIG. 6 is a side sectional view showing a second embodiment for implementing the dielectric barrier discharge lamp of the present invention. In this embodiment, the arc tube LT of the dielectric barrier discharge lamp EXL is different.

  That is, in the arc tube LT, the airtight container 1 has a double tube structure, the discharge space 1a formed inside is cylindrical, and the internal electrode 2 is located inside the airtight container 1 ′ inside the airtight container 1 ′. It is arranged on the outer surface.

  The internal electrode 2 ′ has a cylindrical shape because it is disposed on the cylindrical outer surface of the hermetic container 1 ′. And it forms using the board | plate material and mesh material which consist of an electroconductive material. Further, the airtight container 1 is disposed in close contact with the outer surface of the airtight container 1 having a cylindrical shape. The external electrode OE has the same configuration and arrangement with respect to the airtight container 1 as in the first embodiment.

    7 to 10 show an ultraviolet cleaning apparatus as one embodiment for carrying out the ultraviolet irradiation apparatus of the present invention. FIG. 7 is a front sectional view, FIG. 8 is a bottom view, and FIG. It is sectional drawing which follows a 'line. In each figure, the same parts as those in FIGS. 1 to 4 are denoted by the same reference numerals and description thereof is omitted. The ultraviolet irradiation device UVW includes an ultraviolet irradiation device main body 21, a high frequency lighting circuit 22, and a plurality of dielectric barrier discharge lamps EXL.

  In the present invention, the ultraviolet irradiation device UVW means any device that uses ultraviolet rays generated from the dielectric barrier discharge lamp EXL. For example, a semiconductor stepper, a light cleaning device, a light curing device, a light drying device, and the like. The ultraviolet irradiating device main body 22 is constituted by the remaining part excluding the dielectric barrier discharge lamp EXL and the high frequency generating circuit 22 from the ultraviolet irradiating device UVW.

  As shown in each drawing, a plurality of dielectric barrier discharge lamps EXL can be used as necessary. The air flow forming means AB has a single configuration with respect to the plurality of dielectric barrier discharge lamps EXL and is disposed on the lower surface of the ultraviolet irradiation apparatus main body 22. The dielectric barrier discharge lamp EXL has the same structure as the first embodiment shown in FIGS. 1 to 4 except for the airflow forming means AB.

  The air flow forming means AB is disposed on the lower surface of the ultraviolet irradiation device main body 22.

  The high frequency lighting circuit 22 lights the dielectric barrier discharge lamp EXL. The high-frequency lighting circuit 22 includes high-frequency generating means, generates a high-frequency voltage, and supplies the dielectric barrier discharge lamp with high-frequency power necessary for lighting. The high frequency generates a pulse voltage having a repetition frequency of 10 kHz or more, preferably 100 kHz to 2 MHz.

  The high-frequency lighting circuit 22 may have any other configuration as long as it outputs a pulse voltage. For example, a rectangular wave pulse can be obtained by using a rectangular wave output inverter.

  Thus, in the present invention, since the dielectric barrier discharge lamp EXL includes the air flow forming means AB, the ultraviolet irradiation device UVW that prevents the adhesion of impurities to the surface of the hermetic container and reduces the decrease in the ultraviolet illuminance is provided. Can be realized.

  By the way, the ultraviolet irradiation device main body 21 has a box shape as a whole, and the inside is divided into an ultraviolet irradiation chamber 21a and a power supply chamber 21b in the vertical direction. The ultraviolet irradiation chamber 21a and the power supply chamber 21b are configured such that one end thereof can be opened and closed by a hinge 21c.

  As will be described later, a plurality of dielectric barrier discharge lamps EXL are arranged in parallel in the ultraviolet irradiation chamber 21a. The plurality of dielectric barrier discharge lamps EXL have their external electrodes formed as a single block. Therefore, a plurality of concave curved surfaces of the external electrode OE are arranged in parallel in an adjacent state. In addition, the ultraviolet irradiation chamber 21a is fixedly disposed above the irradiation object transporting means in the cleaning apparatus, and the irradiation object (not shown) that has an open lower surface and passes directly below the lower surface. It is configured to irradiate vacuum ultraviolet light at a very close position.

  The power supply chamber 21b accommodates therein a high-frequency lighting circuit 22 and a control circuit (not shown), and is rotatable upward in FIG. 15 with the hinge 21c as a rotation center. In addition, 21b1 is a handle for gripping the power supply chamber 21b during rotation, 21b2 is a handle for transporting the ultraviolet irradiation apparatus main body 21 or the power supply chamber 21b, and 21b3 is a protector for the power supply wiring.

  The high frequency lighting circuit 22 is housed in the power supply chamber 21b, converts the power introduced into the power supply chamber 21b via the power supply wiring protector 21b3, generates a high frequency voltage, and a plurality of dielectric barrier discharge lamps. Power is supplied to each EXL.

The partial cross section front view of the 1st form for implementing the dielectric barrier discharge lamp of this invention Similarly, partially cutaway front view of arc tube Similarly, a partially cut-out front view of the arc tube support and power supply Same side sectional view The graph which shows the change of the ultraviolet illumination intensity with respect to the lighting time of the dielectric barrier discharge lamp in the 1st form of this invention with that of a comparative example Side surface sectional view which shows the 2nd form for implementing the dielectric barrier discharge lamp of this invention Front sectional drawing which shows the ultraviolet-ray cleaning apparatus as one form for implementing the ultraviolet irradiation device of this invention Similarly bottom view Sectional view along line IX-IX 'in FIG.

Explanation of symbols

      DESCRIPTION OF SYMBOLS 1 ... Airtight container, 2 ... Internal electrode, 4 ... Feed line, 5 ... Holding part, 8 ... Positioning arm, AB ... Airflow formation means, EXL ... Dielectric barrier discharge lamp, HFI ... High frequency lighting circuit, LT ... Arc tube , OE ... External electrode

Claims (2)

An airtight container having an elongated tubular shape made of a material that transmits ultraviolet light;
An excimer-producing gas enclosed in an airtight container;
A long internal electrode arranged to generate a dielectric barrier discharge in the hermetic vessel over substantially the entire length in the tube axis direction;
An external electrode disposed on the outer surface of the hermetic container along the tube axis direction and acting to generate a dielectric barrier discharge in the hermetic container by cooperating with the inner electrode;
Airflow generating means for forming an airflow across the front surface along the tube axis direction of the airtight container;
A dielectric barrier discharge lamp comprising: A dielectric barrier discharge lamp according to claim 1;
An ultraviolet irradiation device body provided with a dielectric barrier discharge lamp;
A high-frequency lighting circuit for lighting a dielectric barrier discharge lamp;
An ultraviolet irradiation device comprising:

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