JP2001155687A - Dielectric barrier discharge lamp device, dielectric barrier discharge lamp lighting device and ultraviolet irradiation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric barrier discharge lamp device, a dielectric barrier discharge lamp lighting device using the same and a ultraviolet irradiation device that can suppress the deposition of ion into a irradiated matter without causing the increase of irradiation non-uniform for the irradiated matter. SOLUTION: In the device, there are provided an airtight vessel 1 in the form of thin and long tube comprising a ultraviolet ray transmitting material, an inner electrode 2 sealed and mounted into the airtight vessel and arranged into a central axis direction along with extending along substantially central axis direction of the air tightness vessel, a dielectric barrier discharge lamp DBL having an excimer component gas in the form of net sealed into the airtight vessel and an outer electrode in the form of net arranged into an outer surroundings of the airtight vessel, and an outer surrounding vessel 6 in the form of thin and long tube comprising the ultraviolet ray transmitting material accommodating the dielectric barrier discharge lamp.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric barrier discharge lamp device, a dielectric barrier discharge lamp lighting device using the same, and an ultraviolet irradiation device.

[0002]

2. Description of the Related Art Excimer discharge lamps which emit a near-monochromatic radiation by discharging an electrodeless discharge of a rare gas such as xenon or a mixed gas such as xenon or krypton and chlorine are described in a number of documents. It has been known for some time.

[0003] Conventionally, a dielectric barrier discharge lamp generally used includes a coaxial cylindrical discharge vessel formed by separating an inner tube and an outer tube and closing both ends thereof with an annular end plate and a circular end plate. Used. The outer tube also serves as a radiation outlet window.

One of a pair of electrodes disposed on the coaxial cylindrical discharge vessel is a conductive mesh electrode, and is mounted on the outer tube of the coaxial discharge vessel. The other electrode is a conductive thin-film electrode, which is formed on the inner tube of the coaxial discharge vessel and also serves as a reflector.

[0005] Further, caps are mounted on both end plates of the coaxial cylindrical discharge vessel, respectively, and are used for supporting a dielectric barrier discharge lamp.

[0006] Then, a high frequency high voltage is applied between the conductive mesh electrode and the conductive thin film electrode from a power source to supply electric energy required for dielectric barrier discharge.

[0007] The dielectric barrier discharge is a so-called silent discharge, in which a pulsed current flows. This pulsed current has a high-speed electron flow and many pauses, so the substance that emits ultraviolet light, such as xenon, is temporarily combined with the molecular state (excimer state) and reabsorbed when returning to the ground state. Since ultraviolet rays with a small amount are efficiently emitted, attempts are being made to use them for the purpose of surface modification and residue treatment in, for example, a light cleaning (dry cleaning) step of a liquid crystal glass substrate or a semiconductor wafer substrate.

The reason for using an electrode having a mesh structure is to cause a stable discharge to occur over a large area. During stable discharge, light emission is observed near the intersection of the mesh.

The dielectric barrier discharge lamp using the above-mentioned conventional dielectric barrier discharge has a relatively large amount of ultraviolet rays generated, but has the following problems. That is, since a discharge occurs through two glass walls serving as dielectrics, a high-frequency high voltage of several kV is required. For this reason, the high-frequency transformer that generates a high voltage not only becomes extremely large but also difficult to manufacture and expensive. In addition, the structure of the discharge vessel is complicated, and the amount of quartz glass used increases, which also increases the cost.

On the other hand, there has been proposed a dielectric barrier discharge lamp which performs a dielectric barrier discharge stably without applying the high voltage as described above using an elongated tubular airtight container,
It is described in JP-A-11-111235. In this dielectric barrier discharge lamp, one of the electrodes is exposed and sealed as an internal electrode extending along the center axis direction in an elongated tubular airtight container filled with excimer-produced gas, and the other electrode is externally sealed. The electrodes are configured in a mesh structure. In addition, when the internal electrodes are electrically heated from the outside, the starting electrons can be emitted and the starting voltage can be greatly reduced. In addition, since it has a simple structure and uses a small amount of quartz glass, it can be obtained at low cost.

[0011]

However, in the device disclosed in JP-A-11-111235, since the mesh-shaped electrodes are exposed on the outer surface of the discharge lamp, cleaning of the outer surface of the lamp is difficult, and maintenance is difficult. There is an obstacle that it is not excellent.

Further, since the mesh electrode is exposed,
The ions generated at the electrodes are easily released to the outside world, and for example, the ions may adhere to an object to be irradiated such as a liquid crystal substrate, which may cause the object to be charged to cause dust collection or the like.

In order to prevent ions generated by the mesh-shaped electrodes from adhering to the object to be irradiated, a panel made of, for example, synthetic quartz, which is transparent to ultraviolet rays, is disposed between the discharge lamp and the object to be irradiated. However, since the incident angle of the radiated light from the discharge lamp to the panel is not uniform, light scattering and refraction spots due to the panel are liable to occur, and irradiation unevenness to the irradiation object increases.

In particular, the shorter the wavelength of the light emitted from the discharge lamp, the higher the refractive index of the quartz glass becomes, as shown in Table 1, so that light scattering and refraction spots due to the panel become remarkable,
Irradiation unevenness with respect to the irradiation target increases.

[Table 1]

The present invention provides a dielectric barrier discharge lamp device capable of suppressing ion attachment to an irradiation object without increasing irradiation unevenness on the irradiation object, a dielectric barrier discharge lamp lighting device using the same, and a dielectric barrier discharge lamp lighting device using the same. It is an object to provide an ultraviolet irradiation device.

[0016]

According to a first aspect of the present invention, there is provided a dielectric barrier discharge lamp device, comprising: an elongated tubular hermetic container made of a material that transmits ultraviolet light; A dielectric barrier discharge lamp having an internal electrode extending along the central axis direction, an excimer generation gas sealed in a hermetic container, and a mesh-like external electrode provided on the outer periphery of the hermetic container. And an elongate tubular envelope made of a UV-transmissive material for accommodating the dielectric barrier discharge lamp.

In the present invention and each of the following inventions, definitions and technical meanings of terms are as follows unless otherwise specified.

<About the airtight container>

An airtight container made of a material that transmits ultraviolet light is
Generally, it can be manufactured using quartz glass such as synthetic quartz glass such as Sprazil (trade name). However, the present invention may be made of any material as long as it is transparent to ultraviolet light.

The outer diameter and thickness of the hermetic container are not limited, but in order to reduce the starting voltage as much as possible, the outer diameter must be 25 m.
m, preferably 15 mm or less, and a wall thickness of 2 mm or less, preferably about 0.3 to 1.5 mm.

The length of the airtight container is not limited at all and can be any length according to the required effective irradiation length.

Generally, an exhaust pipe is connected to the airtight container as a means for evacuating the inside of the airtight container and then filling the excimer generated gas. In the present invention, when the exhaust pipe is connected, the exhaust pipe may be connected to any part of the airtight container, but by connecting the exhaust pipe to the side surface, the connection work of the exhaust pipe and the exhaust / sealing work become easy. When the gas is exhausted through the exhaust pipe, the excimer product gas is sealed in the airtight container from the exhaust pipe, and the exhaust pipe is chipped off to form an exhaust chip. However, a chipless type airtight container that does not use an exhaust pipe may be used.

The airtight container is not limited to a straight tube as long as it is tubular, and may be curved. The cross-sectional shape of the tube is generally circular, but a desired cross-sectional shape such as an ellipse or a square can be used if necessary.

<Regarding the internal electrode>

The internal electrodes are made of tungsten, molybdenum,
Although made of a refractory metal such as nickel, tungsten is effective in lowering the starting voltage because tungsten has a relatively small work function and easily emits electrons.

If the internal electrode is sealed inside the airtight container and extends substantially along the central axis of the airtight container, the shape of the internal electrode is limited to a coil shape, a rod shape, a line shape or a plate shape. do not do. In addition, "almost along the central axis" means that it may not only coincide with the central axis but also be slightly off the central axis.

Furthermore, in order to dispose the internal electrodes along the central axis, the internal electrodes may collide with the inner surface of the airtight container at a suitable number of locations in the longitudinal direction of the internal electrodes, for example, to strike the inner surface of the airtight container. Accordingly, it is allowed to use a position corrector that positions the internal electrode substantially along the central axis of the airtight container. Such a configuration is effective for regulating the disposition position of the internal electrode when the airtight container is long.

If the internal electrodes are arranged so as to be located substantially along the central axis of the hermetic container using the position locator, the distance between the internal electrodes and the external electrodes can be kept constant. Irradiation unevenness of ultraviolet light on the lower surface of the dielectric barrier discharge lamp due to sagging of the internal electrode can be reduced.

The position locator may be formed of either a conductor or an insulator. In particular, if the position locator is formed of an insulating material such as a quartz glass material, the potential gradient between the internal and external electrodes can be increased. This is preferable because the influence on the surface can be suppressed.

Further, an appropriate number of position determiners can be dispersed and arranged along the length direction of the internal electrodes as necessary.

In the case of the position corrector made of a conductor, one end is wound in a linear shape and wound around the internal electrode and fixed, and the other end is wound in a ring shape close to the inner surface of the airtight container, or the middle portion is formed in a ring shape. It is possible to adopt a configuration in which both ends are wound around and fixed to the internal electrodes. Further, a configuration may be adopted in which a plurality of arms are radially projected around the internal electrode so as to approach the inner surface of the airtight container.

In the case of a position corrector made of an insulator, a structure is adopted in which glass, ceramics, pottery, or the like is formed into a disk shape whose peripheral edge is close to the inner surface of the airtight container, and the internal electrode is supported at the center. be able to.

In order to seal the internal electrode to the end of an airtight container made of quartz glass, a sealing structure using a sealing metal foil, which is frequently used when compactly sealing quartz glass, is employed. it can. Further, the sealing metal foil can be hermetically sealed by pinch sealing the quartz glass.

<Excimer Product Gas>

The excimer product gas may be a rare gas such as xenon, krypton, argon or helium or a mixed gas of a rare gas and a halogen such as fluorine, chlorine, bromine or iodine, for example, XeCl, KrCl, etc. Alternatively, a gas that does not produce excimer, such as neon, may be mixed in addition to the excimer producing gas.

Here, the filling pressure of the excimer generated gas is not limited, but as the filling pressure increases, the ultraviolet output increases, while the starting voltage and the lighting voltage also increase.
An appropriate pressure range, for example, about 10 to 70 kPa is suitable.

<Regarding External Electrodes>

The external electrode acts to generate a dielectric barrier discharge between the internal electrode and the internal electrode. In order to guide ultraviolet light emitted from the excimer generated by the dielectric barrier discharge to the outside, and to emit ultraviolet light. To increase, a mesh-like structure has been conventionally employed.

As the mesh shape, for example, mesh knitting,
A turtle shell, a flat knit, a punching plate, or the like can be used. Since the knitted fabric is particularly excellent in elasticity, it is easy to prepare a cylindrical mesh structure with an inner diameter larger than the outer diameter of the airtight container, place it outside the airtight container, and pull it toward both ends. By reducing the diameter, the external electrode can be brought into contact with the outer surface of the airtight container. Also, wrap the mesh structure spread out in a plate shape around the side of the airtight container and butt or overlap both sides, then tie it through a wire to the side edge of the mesh structure, or fold it into a U-shape etc. It may be secured using a curved mechanical lock.

The external electrode can be formed using a suitable metal such as stainless steel, nickel or the like. Here, the external electrode is as thin as possible, preferably 0.05 to 0.05, in order to increase the generation of ultraviolet rays due to dielectric barrier discharge.
The mesh structure is preferably formed using a metal wire of about 0.5 mm.

Further, in place of the metal wire, a conductive paste can be directly printed or transferred onto the outer surface of the hermetic container and baked to form a mesh electrode. This is preferable because the external electrode can be in close contact with the airtight container. Here, Ag, Pd, Pt, Au, Ni
Among them, a conductive paste obtained by kneading at least one kind of conductive metal particles and a Pb, B-based or quartz glass material can be used. Alternatively, a mesh-shaped electrode may be formed by printing a pattern of this kind of conductive paste on a resin film, pasting the resin film to an airtight container, and transferring the pattern. By the method, a mesh-like pattern can be formed in the airtight container. Further, a metal film acting as a reflective film can be formed on a part of the outer surface of the airtight container by using these printing techniques.

<About the surrounding container>

The surrounding container accommodates a dielectric barrier discharge lamp, and is generally made of a material that transmits ultraviolet light in addition to quartz glass, and has an elongated tubular shape, like the airtight container.

Further, a medium for cooling the dielectric barrier discharge lamp is circulated in a space formed between the inner surface of the outer container and the outer surface of the airtight container to suppress the temperature rise of the discharge lamp. A decrease in luminous efficiency can be prevented.
The medium for cooling should be selected from those which have little absorption of the emitted light of the discharge lamp and which do not promote oxidation of the metal. For example, an inert gas such as nitrogen gas is suitable.

<Other Configurations>

In order to facilitate the support of the dielectric barrier discharge lamp and the energization of the electrodes, it is possible to mount caps having an appropriate shape and structure on both ends of the hermetic container.

<Operation of the Present Invention>

When a high-frequency voltage is applied between the internal electrode and the external electrode, a pulse-like dielectric barrier discharge occurs near the intersection of the meshes of the external electrodes, and ultraviolet rays having a wavelength of the resonance line of the rare gas are generated. . For example, when xenon is sealed, short-wavelength ultraviolet rays of 172 nm are generated.

Further, since the internal electrodes are exposed in the hermetic container, the starting voltage and the lighting voltage are reduced. further,
Since the discharge lamp provided with the external electrodes is accommodated in a tubular envelope, external discharge of ions generated by the external electrodes can be prevented. In addition, since the outer container is formed of the same shape as the airtight container, the incident angle of the radiation light of the discharge lamp with respect to the outer container is substantially uniform, and light scattering spots and refraction spots in the outer container can be suppressed. .

Therefore, the dielectric barrier discharge lamp device according to the present invention has an effect that it is possible to suppress the attachment of ions to the irradiation object without increasing irradiation unevenness on the irradiation object.

According to a second aspect of the present invention, there is provided a lighting device for a dielectric barrier discharge lamp, wherein the high frequency voltage is applied between an internal electrode and an external electrode of the dielectric barrier discharge lamp. And generating means.

In the present invention, “high frequency” refers to 10 k
The high frequency generating means generates a high frequency voltage and supplies the dielectric barrier discharge lamp with the high frequency power required for lighting the same. The oscillation frequency is preferably 3
It is 0 kHz to 2 MHz.

Preferably, the high frequency generator applies a high frequency voltage of 300 to 800 V to the dielectric barrier discharge lamp when the dielectric barrier discharge lamp is stably operated.
Furthermore, the starting voltage of the dielectric barrier discharge lamp is 2 to
It is 2.3 kVp-p, and can be easily started by increasing the secondary open-circuit voltage of the high frequency generating means to the starting voltage. In this case, it is preferable that the high frequency generating means is mainly composed of a parallel inverter because a high boosting ratio can be easily obtained. Since the high-frequency output waveform is a sine wave, noise is reduced when the dielectric barrier discharge lamp is turned on. However, if necessary, a starting pulse voltage generating means can be used in addition to the high frequency generating means.

If the dielectric barrier discharge lamp and the high-frequency generating means are electrically connected as required, they can be arranged at positions separated from each other. Unlike a general discharge lamp, the dielectric barrier discharge lamp does not need to connect current limiting means in series. However, in order to adjust the lamp current to a predetermined value, lighting by connecting an appropriate value of impedance in series can be performed as necessary. Also,
When connecting the dielectric barrier discharge lamp to the high frequency generating means, grounding the external electrodes reduces noise generation.

According to a third aspect of the present invention, there is provided an ultraviolet irradiation device, comprising: an ultraviolet irradiation device main body; and the dielectric barrier discharge lamp device according to the second embodiment supported by the ultraviolet irradiation device main body. .

In the present invention, the term "ultraviolet irradiation device" means any device that utilizes ultraviolet light generated from a dielectric barrier discharge lamp. For example, there are a semiconductor stepper, a light cleaning device, a light curing device, a light drying device, and the like.

The "ultraviolet irradiation device main body" means the remaining portion of the ultraviolet irradiation device excluding the dielectric barrier discharge lamp and the high frequency generating means.

Further, one or a plurality of dielectric barrier discharge lamps can be used as needed.

According to a fourth aspect of the present invention, there is provided the ultraviolet irradiating apparatus according to the third aspect, wherein the ultraviolet irradiating apparatus main body includes a lamp support having a concave reflecting surface on an inner surface thereof, and a dielectric barrier discharge lamp apparatus. Is characterized in that the dielectric barrier discharge lamp is accommodated in such a manner that the dielectric barrier discharge lamp is deviated so as to be separated from the concave reflecting surface.

The dielectric barrier discharge lamp device is supported by a lamp support having an inner surface provided with a concave reflection surface of the ultraviolet irradiation device main body, and an outer container of the dielectric barrier discharge lamp device has a dielectric barrier discharge lamp. Since the lamp accommodates the dielectric barrier discharge lamp with the lamp deflected away from the concave reflection surface, the dielectric barrier discharge lamp is consequently in a direction relatively away from the concave reflection surface, that is, covered. Because of the deflection in the direction of the irradiation body, an increase in direct radiation from the discharge lamp can be expected.

[0061]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view showing an embodiment of a dielectric barrier discharge lamp device according to the present invention, and FIG. 2 is a front view showing a state where external electrodes are also removed. In each figure, 1
Is an airtight container, 2 is an internal electrode, 3 is an external lead wire, 4 is an external electrode, 6 is an envelope, and DBL is a dielectric barrier discharge lamp.

The hermetic container 1 is made of quartz glass and has an elongated cylindrical hollow portion 1a having an outer diameter of 11.5 mm and an inner diameter of 9.5 mm, and a sealing portion 1b and a hollow portion 1a formed at both ends of the hollow portion 1a. It has an exhaust tip 1c formed on the side surface and has a total length of 650 mm.

The sealing portion 1b has a molybdenum foil 1b1 inside.
Is embedded in a pinch seal structure.
The airtight container 1 is formed on the central side surface. Xenon is sealed in the hollow part 1a of the airtight container 1 as an excimer production gas at about 40 kPa.

The internal electrode 2 is made of Al, S having a wire diameter of 1.1 mm.
It is a doped tungsten rod to which a small amount of i and K are added and subjected to high temperature treatment, and both ends of the doped tungsten rod are connected to a fine tungsten wire 2b having a diameter of 0.3 mm. Here, Al, Si,
It is known that when doped tungsten containing a small amount of K is treated at a high temperature, the secondary crystallization of tungsten, that is, coarse crystallization, is caused. Thus, the phenomenon that the doped tungsten hardly sags at a high temperature during operation of the discharge lamp ( Non-sag) is particularly preferable.

The internal electrode 2 is disposed so as to penetrate the center of the quartz positioning ruler 5 which forms a cross at three places near the center and both ends thereof. The arrangement is regulated almost along the axis.

The tungsten thin wire 2b has both ends linear portions 2b supported by sealing portions 1b formed at both ends of the airtight container 1, and is welded to one end of the molybdenum foil 1b1. The external lead wire 3 has a base end exposed to the outside, a tip end embedded in the sealing portion 1b, and welded to the other end of the molybdenum foil 1b1.

The external electrode 4 is formed by braiding a knitted mesh structure shown in an enlarged scale in FIG. 3 into a cylindrical shape, and is in close contact with the outer surface of the airtight container 1 and surrounds the entire periphery. Projecting outward through the mesh structure.

The knitted knitting of the external electrode 4 is formed using a stainless steel wire (# 304) having a wire diameter of 0.1 mm. Mesh interval is 2.8mm long, 3mm wide
It is.

Further, in order to mount the external electrode 4 on the airtight container 1, the knitted braided structure is formed into a cylindrical body having a diameter of 20 mm, and the airtight container 1 is inserted into the cylindrical body, and then the both ends of the cylindrical body are inserted. And pull it toward both ends. Then, the cylindrical body contracts while the mesh is deformed by being elongated. The exhaust tip portion 1c pushes and expands the mesh portion in the process of pulling the cylindrical body, and penetrates the external electrode 4 to protrude to the outside as described above. The cylindrical body is deformed from the portion through which the exhaust tip portion 1c penetrates, adheres to the airtight container 1, and gradually expands in both ends after the shape is stabilized, so that the mesh is deformed into a rhombus, but the shape is stable. The state in which it is in close contact with the airtight container 1 is maintained. Since the exhaust tip 1c penetrates the external electrode 4, the external electrode 4 is fixed to the airtight container 1 so that the external electrode 4 does not accidentally fall off.

Instead of such a mesh made of metal wires, for example, a silver-palladium conductive paste is printed directly or indirectly on the outer surface of the airtight container 1 to form a mesh-like pattern. The external electrode 4 can also be used.

The dielectric barrier discharge lamp DBL thus configured has a rated value of 90 W in lamp power, and is housed in an elongated cylindrical quartz glass envelope 6 having an outer diameter of 18 mm and an inner diameter of 16 mm. It has a double pipe structure as a whole. Further, both ends of the outer container 6 are connected to the external lead wires 3.
Is closed by the closing member 7 while penetrating through.

Here, ventilation holes (not shown) are provided in the closing members 7 on both sides so that nitrogen gas sent from an external device flows through the space between the surrounding container 6 and the airtight container 1. Thereby, the temperature rise of the airtight container 1 is suppressed, and the decrease in the luminous efficiency is reduced.

FIG. 4 is a circuit diagram showing one embodiment of the dielectric barrier discharge lamp lighting device of the present invention. In the figure, the same parts as those in FIG. AS is a commercial AC power supply, RDC is a rectified DC power supply, SW is a blinking switch, AF is an active filter, HFI is a high-frequency inverter, and C1 is a capacitor.

The rectified DC power supply RDC comprises a full-wave rectifier circuit and outputs a non-smooth rectified DC voltage. The active filter AF is composed of a chopper circuit, smoothes an unsmoothed rectified DC voltage, and outputs a DC voltage whose input current has a high power factor and low harmonic distortion and is converted to a required value. .

The high-frequency inverter HFI is of a parallel inverter circuit type and comprises a pair of switching means Q1, Q
2. Output transformer TR, constant current inductor L, resonance capacitor C2, starting resistors R1, R2 and feedback winding FC
It is constituted by. A pair of switching means Q
1 and Q2 are, for example, bipolar transistors, and have both emitters connected to the negative electrode of the DC output terminal of the active filter AF.

The output transformer TR is composed of an insulating transformer and has a primary winding p and a secondary winding s. One end of the primary winding p is connected to the switching means Q1.
And the other is connected to the collector of the switching means Q2. One end of the constant current inductor L is connected to the positive terminal of the output terminal of the active filter AF,
The other end is connected to the center tap of the primary winding p of the output transformer TR.

The resonance capacitor C2 is connected to the output transformer TR
To the two ends of the primary winding p to form a parallel resonance circuit with the inductance of the primary winding. Starting resistor R1
Is connected to the base of the switching means Q1 and the positive terminal of the output terminal of the active filter AF. Starting resistor R2
Is similarly connected to the base of the switching means Q2 and the positive terminal of the output terminal of the active filter AF. The feedback winding FC is magnetically coupled to the output transformer TR, and has one end connected to the base of the switching means Q1 and the other end connected to the base of the switching means Q2.

Next, the circuit operation of the high-frequency inverter HFI will be described. When the switching means Q1 is turned on, current flows from the positive electrode of the active filter AF to the constant current inductor L, from the center tap of the primary winding p of the output transformer TR to the upper half of the figure and to the negative electrode of the active filter AF via the switching means Q1. Flows. At this time, the switching means Q2 is off. Next, when the switching means Q2 is turned on, the active filter A is connected to the constant current inductor L from the positive electrode of the active filter AF, to the lower half of the figure from the center tap of the primary winding p of the output transformer TR, and to the active filter A via the switching means Q2.
A current flows to the negative electrode of F. At this time, the switching means Q
1 is off.

Then, the primary winding p of the output transformer TR
, Alternating currents flow in the opposite direction, that is, alternating current,
Since the parallel resonance circuit of the resonance capacitor C2 and the inductance of the primary winding p resonates at the fundamental frequency of the alternating current,
A sine wave AC voltage is obtained in the secondary winding s.

Incidentally, an AC voltage is also induced in the feedback winding FC magnetically coupled to the output transformer TR to alternately supply a drive signal to the switching means Q1 and Q2, so that the high-frequency inverter HFI is self-excited. Oscillate.

The activation of the high-frequency inverter HFI is as follows.
When a drive signal is supplied from the positive electrode at the output terminal of the active filter AF to the bases of the switching means Q1 and Q2 via the starting resistors R1 and R2, one of the switching means is turned on first. When one of the switching means starts to be turned on, the switching means which is turned on from the feedback winding FC is fed back as a current having a polarity in the on direction, so that the switching means is turned on reliably, and conversely, the one which is turned off is turned off. The high-frequency inverter HFI is turned off without fail because it acts as a polarity in the off direction with respect to the switching means.

The capacitor C1 regulates the lamp current flowing through the dielectric barrier discharge lamp DBL.

The dielectric barrier discharge lamp DBL can adopt the above embodiment. The internal electrode 2 is connected to one end of the secondary winding s of the output transformer TR via the capacitor C1. The external electrode 5 is connected to the other end of the secondary winding s and is grounded.

Next, the circuit operation of the entire dielectric barrier discharge lamp lighting device will be described.

When the power switch SW is turned on, a non-smoothed rectified DC voltage is applied from the rectified DC power supply RDC to the input terminal of the active filter AF, so that a required value of the smoothed DC voltage appears at the output terminal. . Since this DC voltage is applied to the input terminal of the high-frequency inverter HFI, the high-frequency inverter HFI starts. When the high-frequency inverter HFI is activated, a sine-wave high-frequency AC output voltage is applied to the dielectric barrier discharge lamp D via the capacitor C1.
Since the voltage is applied between the internal electrode 2 and the external electrode 5 of the BL, the dielectric barrier discharge lamp DBL is turned on. When the dielectric barrier discharge lamp DBL is turned on, ultraviolet light having a wavelength of 172 nm, which is a resonance line of xenon, is generated.

FIG. 5 is a cross-sectional view of a main part showing a first embodiment of the ultraviolet irradiation apparatus of the present invention.

In the figure, DBL denotes a dielectric barrier discharge lamp, 12 denotes a lamp support, and 13 denotes a work to be irradiated such as a liquid crystal substrate.

The dielectric barrier discharge lamp DBL has a structure adopting the above-described embodiment. In order to correspond to a work having a size of 550 × 650 mm, for example, a large number of 36 lamps are arranged at a small interval, and a total of 7 lamps are used. 0.0mW /
The arrangement is made so as to have an ultraviolet radiation intensity of not less than square centimeters, and eight of them are shown in the figure. The same parts as those in FIG. 1 are denoted by the same reference numerals.

The lamp support 12 is made of aluminum, has a concave reflecting surface 12a on the lower surface, and a cooling water passage 12 inside.
b.

The dielectric barrier discharge lamp device DBL is supported in a state where the envelope 6 is in contact with the concave reflecting surface 12a of the lamp support 12, and a high-frequency generating means (not shown).
Is electrically connected to the external electrode 4 using the lamp support 12 as a conductive path. The lamp support 12 is grounded.

The envelope 6 accommodates the dielectric barrier discharge lamp with the airtight container 1 eccentric so as to be separated from the concave reflecting surface 12a.

The work 13 is a dielectric barrier discharge lamp D
The lamp is moved so as to be able to receive ultraviolet irradiation by approaching the lamp to a position of 3 mm from below the BL.

According to the present embodiment, the dielectric barrier discharge lamp DBL is deviated relatively to the direction away from the concave reflecting surface 12a, that is, to the work 13, so that the dielectric barrier discharge lamp DBL Increase in direct radiation from Accordingly, the uniformity of the UV illuminance at the close position does not decrease, and the UV irradiation can be performed while the object to be irradiated with the UV light is brought close to a close distance.

[0095]

According to the first to fourth aspects of the present invention, the dielectric barrier discharge lamp having an elongated tubular shape is accommodated in the elongated tubular envelope, so that the irradiation unevenness of the object to be irradiated can be increased. Without coming, ion attachment to the irradiation object is suppressed.

According to the third and fourth aspects of the present invention,
An ultraviolet irradiation device capable of preventing deterioration of the uniformity of ultraviolet illuminance can be provided.

Furthermore, according to the fourth aspect of the present invention, there is provided an ultraviolet irradiating apparatus which does not reduce the uniformity of the ultraviolet illuminance at a close position and which can irradiate an ultraviolet light by approaching an object to be irradiated with the ultraviolet light as close as possible. be able to.

[Brief description of the drawings]

FIG. 1 is a front view showing one embodiment of a dielectric barrier discharge lamp device of the present invention.

FIG. 2 is a front view showing a state in which external electrodes are also removed.

FIG. 3 is a front view of an enlarged main part of the external electrode.

FIG. 4 is a circuit diagram showing one embodiment of a lighting device for a dielectric barrier discharge lamp according to the present invention.

FIG. 5 is a sectional view of an essential part showing an embodiment of an ultraviolet irradiation device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Airtight container 1a ... Hollow part 1b ... Sealing part 1b1 ... Molybdenum foil 1c ... Exhaust chip part 2 ... Internal electrode 2a ... Coil part 2b ... Both ends straight part 3 ... External lead wire 4 ... External electrode 5 ... Positioning corrector 6 ... Enclosure DBL ... Dielectric barrier discharge lamp 12 ... Lamp support

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuhiko Yoshikawa F-term (reference) 3K072 AA00 CA16 in 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo

Claims (4)

[Claims] 1. An elongate tubular airtight container made of a material that transmits ultraviolet light, an internal electrode sealed in the airtight container, extending substantially along the central axis of the airtight container, and disposed in the central axis direction. A dielectric barrier discharge lamp having an excimer product gas sealed in the hermetic container and a mesh-shaped external electrode disposed on the outer periphery of the hermetic container; and a UV-transmissive material for housing the dielectric barrier discharge lamp. An elongate tubular envelope. 2. The dielectric barrier discharge lamp device according to claim 1, further comprising: high frequency generating means for applying a high frequency voltage between an internal electrode and an external electrode of the dielectric barrier discharge lamp. Dielectric barrier discharge lamp lighting device. 3. An ultraviolet irradiation device comprising: an ultraviolet irradiation device main body; and the dielectric barrier discharge lamp device according to claim 2 supported by the ultraviolet irradiation device main body. 4. The ultraviolet irradiation device body includes a lamp support having a concave reflecting surface on an inner surface; an outer container of the dielectric barrier discharge lamp device includes a dielectric barrier discharge lamp having a concave reflecting surface. The ultraviolet irradiation device according to claim 3, wherein the dielectric barrier discharge lamp is accommodated so as to be deviated so as to be separated from the dielectric barrier discharge lamp.