JP2008077909A - Dielectrics barrier discharge lamp device and ultraviolet irradiation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dielectric barrier discharge lamp device in which simplification of lamp structure is promoted by making an exterior electrode unnecessary, and an ultra-violet ray irradiation device equipped with this. <P>SOLUTION: The dielectric barrier discharge lamp device is equipped with an airtight container 1 formed in a slender tubular shape composed of an ultraviolet ray translucent material, an excimer-forming gas encapsulated in the airtight container, and a long internal electrode 2 arranged in the airtight container along nearly the total length of its tube axial direction, and is installed with a plurality of the dielectric barrier discharge lamps 10A, 10B adjoining mutually very closely and a high frequency lamp lighting circuit 11 that impresses voltage between the internal electrodes of the plurality of dielectric barrier discharge lamps, while by the voltage impressed between the internal electrodes of the plurality of dielectric barrier discharge lamps adjoining mutually very closely, the internal electrode of the other dielectrics barrier electric discharge lamp seen from respective one dielectric barrier discharge lamp functions as the external electrode to form the dielectric barrier discharge in the airtight container. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a dielectric barrier discharge lamp device including a plurality of dielectric barrier discharge lamps and an ultraviolet irradiation device using the dielectric barrier discharge lamp device.

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. Since 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 light 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 larger 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 irradiated object, 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, the dielectric barrier discharge lamp described in Patent Document 1 has an external electrode for applying a high-frequency voltage between the internal electrode and the internal electrode in order to generate dielectric barrier discharge using the hermetic container as a dielectric. It must be placed in close contact with the outer surface. If the external electrode can be omitted, the lamp structure can be greatly simplified.

  It is an object of the present invention to provide a dielectric barrier discharge lamp device that eliminates the need for external electrodes and simplifies the lamp structure, and an ultraviolet irradiation device that includes the dielectric barrier discharge lamp device.

  The dielectric barrier discharge lamp apparatus according to the present invention is 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 disposed in the airtight container over almost the entire length in the tube axis direction. A plurality of dielectric barrier discharge lamps that are closely adjacent to each other, and a high-frequency lighting circuit that applies a voltage between the internal electrodes of the plurality of dielectric barrier discharge lamps. The internal electrodes of the other dielectric barrier discharge lamp function as external electrodes when viewed from one of the dielectric barrier discharge lamps by the voltage applied between the internal electrodes of a plurality of adjacent dielectric barrier discharge lamps. It is characterized in that dielectric barrier discharge occurs in the container.

  According to the present invention, the other internal electrode of the plurality of adjacent dielectric barrier discharge lamps acts as the external electrode of one dielectric barrier discharge lamp, so that the separate external electrode is omitted and the lamp structure is simplified. It is possible to provide a dielectric barrier discharge lamp device and an ultraviolet irradiation device including the same.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

    1 to 3 show a first embodiment for implementing a dielectric barrier discharge lamp device according to the present invention, FIG. 1 is a circuit block diagram of the dielectric barrier discharge lamp device, and FIG. 2 is a plurality of adjacent dielectrics. FIG. 3 is a partially cutaway front view showing a single dielectric barrier discharge lamp.

In this embodiment, the dielectric barrier discharge lamp apparatus includes a plurality of, for example, a pair of dielectric barrier discharge lamps 10 and a high frequency lighting circuit HFC. <Regarding the dielectric barrier discharge lamp 10> The dielectric barrier discharge lamp 10 is airtight. A container 1, an excimer forming gas and an internal electrode are provided. In addition, as an incidental structure, power supply units 3A and 3B are provided. In addition, the airtight container 1, the excimer forming gas, the internal electrode 2, and the power feeding units 3A and 3B are assembled and integrated in advance.

    (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. 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, since the hermetic container 1 is used by arranging a plurality of dielectric barrier discharge lamps 10 adjacent to each other along the tube axis direction in parallel, it is a straight tube excellent in linearity in the adjacent direction. However, 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 acceptable. In the direction perpendicular to the adjacent direction, the plurality of adjacent dielectric barrier discharge lamps 10 may be curved as long as they have the same shape. Further, the airtight container 1 may have a double tube structure in which a cylindrical discharge space is formed.

    (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.

    (Regarding Internal Electrode 2) The internal electrode 2 is disposed so as to face the internal electrode 2 of the adjacent dielectric barrier discharge lamp 10 so as to be adjacent to each other with the wall surface of the airtight container 1 containing the internal electrode 2 interposed therebetween. It acts as an external electrode of the dielectric barrier discharge lamp 10. 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.

  A preferred configuration example of the internal electrode 2 shown in FIGS. 2 and 3 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, for example, a ring shape, a spiral shape, a coil shape, or a mesh shape. The As shown in FIGS. 2 and 3, in the illustrated embodiment, a plurality of ring-shaped mesh portions 2 b are dispersed in the tube axis direction, and each mesh-shaped portion 2 b is positioned on the central axis of the airtight container 1. Coupling portions 2a formed by winding in a coil shape are coupled at a predetermined interval.

  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. 3, 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.

    (About Feed Units 3A and 3B) The feed units 3A and 3B constitute a feed end for supplying the internal electrode 2 with a current required 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. The power feeding units 3A and 3B are output terminals of a high-frequency lighting circuit HFC described later. Note that one or both of the power feeding units 3A and 3B can be connected to the high-frequency lighting circuit HFC.

    (Regarding Adjacent Form of Plural Dielectric Barrier Discharge Lamps 10) As shown in FIG. 2, the plural dielectric barrier discharge lamps 10 are adjacent to each other so that the airtight containers 1 and 1 are in close contact with each other. In this case, the mesh-like portions 2b of the internal electrodes 2 may or may not face each other. When the power feeding parts 3A and 3B are flat and the width is larger than the outer diameter of the main part of the airtight container 1, the flat surfaces of the power feeding parts 3A and 3B shown in FIG. If it arrange | positions, it will not become a close obstacle of the airtight containers 1 and 1. FIG.

  In the present invention, the number of dielectric barrier discharge lamps is not limited to two as long as it is plural. For example, in the case of three lights, one light is shared and two sets of two lights are made. Then, each set is connected to a high frequency lighting circuit. Therefore, in this case, two high-frequency lighting circuits 11 are used.

  <Regarding the High Frequency Lighting Circuit 11> The high frequency lighting circuit 11 includes one (hereinafter referred to as 10A) internal electrode 2 and the other (hereinafter referred to as 10B) internal electrodes of a plurality of adjacent dielectric barrier discharge lamps 10. A high frequency voltage is applied between the two dielectric barrier discharge lamps 10A and 10B, and the two dielectric barrier discharge lamps 10A and 10B are simultaneously energized to light. In the present invention, as can be understood from the above, one or a plurality of high-frequency lighting circuits 11 are used.

  In the present embodiment, the high-frequency lighting circuit 11 is mainly composed of, for example, a rectified DC power supply RDC, a power switch SW and an inverter INV, and the high-frequency output has one dielectric barrier discharge at one end via a capacitor C1. The other is directly applied to the internal electrode 2 of the lamp 10A and the other is directly applied to the internal electrode 2 of the other dielectric barrier discharge lamp 10B. The capacitor C1 can be connected for the purpose of adjusting the lamp current supplied from the high-frequency lighting circuit 11, but is not an essential component.

  The rectified DC power supply RDC rectifies an AC voltage supplied from the AC power supply AC and outputs a DC voltage. A smoothing circuit can be added if desired.

  The power switch SW is a means for blinking the dielectric barrier discharge lamps 10A and 10B, and the insertion site is not particularly limited. In the illustrated embodiment, the power switch SW is inserted between the rectified DC power supply RDC and the inverter INV. Yes.

  The inverter INV is means for converting a DC voltage into a high-frequency AC voltage, and the circuit format and the like are not particularly limited. For example, the inverter INV is configured by a parallel inverter.

  One end of the output terminal of the high-frequency lighting circuit 11 is connected to the internal electrode 2 of the dielectric barrier discharge lamp 10A via the capacitor C1, as shown in FIG. The other output end is connected to the internal electrode 2 of the dielectric barrier discharge lamp 10B.

  <Operation of Dielectric Barrier Discharge Lamp Device> In the dielectric barrier discharge lamp device of the present embodiment, when the power switch SW of the high frequency lighting circuit 11 is turned on, the inverter INV is activated to generate a high frequency voltage. The high-frequency voltage output from the high-frequency lighting circuit 11 is applied between the internal electrodes 2 and 2 of the plurality of adjacent dielectric barrier discharge lamps 10A and 10B. As a result, in FIG. 1, in the dielectric barrier discharge lamp 10 </ b> A, the inner electrode 2 of the dielectric barrier discharge lamp 10 </ b> B acts as an outer electrode, and dielectric barrier discharge occurs inside the hermetic container 1. Similarly, in FIG. 1, in the dielectric barrier discharge lamp 10 </ b> B, the internal electrode 2 of the dielectric barrier discharge lamp 10 </ b> A acts as an external electrode, and dielectric barrier discharge occurs inside the hermetic container 1.

  When the plurality of dielectric barrier discharge lamps 10A and 10B are turned on, vacuum ultraviolet light having a center wavelength of 172 nm is emitted by the xenon excimer by dielectric barrier discharge. 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.

    FIG. 4 is a circuit block diagram showing a second mode for carrying out the dielectric barrier discharge lamp device of the present invention. In this embodiment, three dielectric barrier discharge lamps 10 (hereinafter referred to as 10A, 10B, and 10C) and two high-frequency lighting circuits 11 (hereinafter referred to as 11A and 11B) are used, and high-frequency lighting is used. The arrangement of the power feeding ends from the circuits 11A and 11B is different from the first embodiment.

  That is, the high frequency lighting circuit 11A has one of its output terminals connected to the internal electrode 2 of the dielectric barrier discharge lamp 10A via the capacitor C1, and the other output terminal adjacent to the dielectric barrier discharge lamp 10A. Directly connected to the internal electrode 2 of the discharge lamp 10B. The high-frequency lighting circuit 11B has one of its output terminals connected to the internal electrode 2 of the dielectric barrier discharge lamp 10C via the capacitor C2, and the other output terminal directly connected to the internal electrode 2 of the adjacent dielectric barrier discharge lamp 10B. Connecting. The other output terminals of the high-frequency lighting circuits 11A and 11B are maintained at the same potential. Further, it is preferable that one power supply portion 3B of the dielectric barrier discharge lamp 10 is covered with an insulator so as not to be exposed to the outside, or not formed so as not to be exposed from the airtight container 1.

  Then, the dielectric barrier discharge lamps 10A and 10B are turned on by the high frequency lighting circuit 11A by causing the internal electrodes 2 and 2 to act as external electrodes, and the dielectric barrier discharge lamps 10C and 10B are respectively connected to the internal electrodes. The high frequency lighting circuit 11B is lit by causing 2 and 2 to act as external electrodes.

  As another configuration, a reflector is arranged in order to increase the ultraviolet illuminance when irradiating the workpiece with ultraviolet rays radiated from a plurality of dielectric barrier discharge lamps 10 or to make the ultraviolet illuminance distribution uniform. Can be set. Further, in order to remove the heat generated by lighting the dielectric barrier discharge lamp 10, a cooling device of a desired system such as a water cooling system can be provided.

    FIG. 5 is a front cross-sectional view showing an ultraviolet cleaning device as an embodiment for carrying out the ultraviolet irradiation device of the present invention. In the figure, the same parts as those in FIGS. The ultraviolet irradiation device includes an ultraviolet irradiation device main body 21, a high-frequency lighting circuit 11, and a plurality of dielectric barrier discharge lamps 10.

  In the present invention, the ultraviolet irradiation device means any device that uses ultraviolet rays generated from the dielectric barrier discharge lamp 10. For example, a light cleaning device, a light curing device, a light drying device, and the like. Further, the ultraviolet irradiation device main body 21 is constituted by a remaining portion excluding the plurality of dielectric barrier discharge lamps 10 and the high-frequency generation circuit 11 adjacent to the dielectric barrier discharge lamp device from the ultraviolet irradiation device.

1 is a circuit block diagram of a first embodiment for implementing a dielectric barrier discharge lamp device of the present invention. Schematic cross-sectional view of a plurality of adjacent dielectric barrier discharge lamps Similarly, a partially cut-out front view of the arc tube support and power supply The circuit block diagram which shows the 2nd form for implementing the dielectric barrier discharge lamp apparatus 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

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Airtight container, 1a ... Discharge space, 1b ... Sealing part, 1b1 ... Sealing metal foil, 2 ... Internal electrode, 2a ... Connection part, 2b ... Mesh-like part, 2c ... End part, 3A, 3B ... Power feeding part DESCRIPTION OF SYMBOLS 10, 10A, 10B ... Dielectric barrier discharge lamp, 11 ... High frequency lighting circuit, INV ... Inverter, RDC ... Rectified DC power supply, SW ... Switch

Claims (2)

It is equipped with 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 long internal electrode disposed in the airtight container over almost the entire length in the tube axis direction. A plurality of adjacent dielectric barrier discharge lamps;
A high frequency lighting circuit for applying a voltage between internal electrodes of a plurality of dielectric barrier discharge lamps;
The internal electrodes of the other dielectric barrier discharge lamp are externally viewed from one of the dielectric barrier discharge lamps by the voltage applied between the internal electrodes of the plurality of dielectric barrier discharge lamps closely adjacent to each other. A dielectric barrier discharge lamp device, wherein the dielectric barrier discharge lamp functions as an electrode and causes dielectric barrier discharge in an airtight container. An ultraviolet irradiation device body;
The dielectric barrier discharge lamp device according to claim 1, wherein the dielectric barrier discharge lamp device is disposed in a main body of the ultraviolet irradiation device;
An ultraviolet irradiation device comprising:

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