JP4054699B2 - Dielectric barrier discharge lamp illumination device and ultraviolet irradiation device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dielectric barrier discharge lamp illumination device and an ultraviolet irradiation device using the same.
[0002]
[Prior art]
Excimer discharge lamps, that is, dielectric barrier discharge lamps that generate a near-unique emission by silently discharging a rare gas such as xenon or a rare gas such as xenon or krypton and a mixed gas such as chlorine are described in many literatures. It has been known for some time. In the dielectric barrier discharge, a pulsed current flows by so-called silent discharge. This pulsed current has a high-speed electron flow and has a long rest period. Therefore, a substance that emits ultraviolet rays, such as xenon, temporarily binds to the molecular state (excimer state) and reabsorbs when returning to the ground state. Efficiently emits less ultraviolet light.
[0003]
As a dielectric barrier discharge lamp, a dielectric barrier discharge lamp that performs a dielectric barrier discharge using an elongated tubular hermetic container is known (see Patent Document 1).
[0004]
In addition, it is a light transmissive, long and thin tube, a light transmissive external electrode on the outer surface of the discharge vessel also serving as a first dielectric for dielectric barrier discharge, and a ratio L / D of length L to diameter D on the inner side. Has also been proposed with an inner electrode made of 30 or more metal rods or metal pipes (see Patent Document 2).
[0005]
Further, the present inventor also provides a dielectric barrier discharge lamp in which the internal electrode is disposed by the action of tension, or the internal electrode is provided with a position restrictor, that is, an anchor, so that the drooping of the internal electrode is suppressed. (See Patent Document 3). According to Patent Document 3, since the anchor is made of a conductive metal, the anchor also functions as a part of the internal electrode, so that the distance between the internal and external electrodes is reduced and the startability is improved.
[0006]
An arc tube having an elongated hermetic container as disclosed in Patent Documents 1 to 3, an internal electrode extending in the axial direction in the hermetic container, and an excimer-generating gas sealed in the hermetic container, and a cooling function The outer tube is externally attached to the outer surface of the hermetic container by press-contacting the arc tube to a lamp body recessed so that a part of the outer surface of the hermetic container fits and interposing an external electrode therebetween. The electrodes can be brought into close contact to cause uniform dielectric barrier discharge along the tube axis direction, and heat generated from the arc tube can be quickly dissipated to maintain a high luminous efficiency.
[0007]
  Power can be supplied to the internal electrode sealed inside the hermetic container from one end or both ends of the internal electrode. However, the dielectricYaWiring is facilitated by carrying out from one end side of the discharge lamp.
[0008]
  In addition, dielectric burrsYaSince the discharge lamp has a low luminous efficiency due to heat generated by the discharge during lighting, a cooling medium passage such as water is formed inside the lamp body as a cooling function of the lamp body, and the cooling medium Is discharged from one end of the lamp body and discharged from the other end.YaCool the discharge lamp and dielectric burrs at the optimum operating temperatureYaThe discharge lamp can be lit with high efficiency.
[0009]
[Patent Document 1]
          JP-A-11-111235
[Patent Document 2]
          JP-A-7-272692
[Patent Document 3]
          JP 2001-084966 A
[Problems to be solved by the invention]
  However, dielectric burrsYaIt was found that the ultraviolet illuminance distribution along the tube axis direction of the discharge lamp is high on the power supply end side of the internal electrode, and conversely low on the terminal end side, so that it is difficult to obtain a uniform UV illuminance distribution in the tube axis direction.
[0010]
  In addition, dielectric burrsYaThe UV illuminance distribution along the tube axis direction of the discharge lamp is high on the inlet side of the cooling medium passage of the lamp body, and conversely low on the outlet side, so that a uniform UV illuminance distribution is obtained in the tube axis direction. I also found it difficult.
[0011]
The present invention relates to a dielectric barrier discharge lamp illuminating device in which, when a work to be irradiated with ultraviolet rays moves relatively in a direction perpendicular to the tube axis, the amount of ultraviolet irradiation to the workpiece is leveled along the tube axis direction, and It aims at providing the ultraviolet irradiation device using this.
[0012]
[Means for achieving the object]
    A dielectric barrier discharge lamp illuminating device according to a first aspect of the present invention is an elongated tubular hermetic container made of an ultraviolet light transmissive material, an internal electrode sealed in the hermetic container along the axial direction and fed from one end, Excimer generation gas sealed in an airtight container and on the outer surface of the airtight containerAlong its axial directionAttachedPower is supplied from the other end of the airtight container.Dielectric burrs in the airtight container through cooperation with internal electrodesYaA plurality of dielectric barrier discharge lamps having external electrodes that act to cause discharge,And external electrodesAgainsteachIt is characterized by arranging the feeding ends in parallel so that they are alternately adjacent.
[0013]
  The dielectric barrier discharge lamp illuminating device of the present invention supplies power to the internal electrodes.Airtight containerMade from one end ofIn addition, power is supplied to the external electrode from the other end of the airtight container.A plurality of dielectric barrier discharge lamps,eachThe power feeding ends are arranged so as to be alternately adjacent to each other. Hereinafter, each component of the dielectric barrier discharge lamp will be described.
[0014]
<Regarding Dielectric Barrier Discharge Lamp> The dielectric barrier discharge lamp includes an airtight container, an internal electrode, an excimer generation gas, and an external electrode.
[0015]
(Regarding the Airtight Container) The airtight container is made of a material that is transparent to ultraviolet rays, and can generally be manufactured using synthetic quartz glass. However, the present invention may be made of any material as long as it is ultraviolet transmissive to vacuum ultraviolet light having a wavelength to be used.
[0016]
In order to increase the ultraviolet output, the outer diameter of the airtight container is preferably 12 mm or more. In order to lower the discharge start voltage, the inner diameter is preferably 25 mm or less. Furthermore, the wall thickness can be 2 mm or less, preferably about 0.3 to 1 mm. On the other hand, the length of the airtight container is not limited at all, and can be set to an arbitrary length, for example, about 1 m, according to the required ultraviolet irradiation length. In particular, according to the present invention, the external electrode can be uniformly pressed in the tube axis direction of the hermetic container by the support means, and therefore, the length may be 1 m or more.
[0017]
An exhaust pipe is connected to the hermetic container as a means for sealing the excimer production gas after exhausting the inside of the hermetic container. In the present invention, the exhaust pipe is connected to one side of the hermetic container and to the side surface of the part exposed to the outside from the lamp body. When exhaust is performed through the exhaust pipe, the excimer generated gas is sealed in the airtight container from the exhaust pipe, and the exhaust pipe is chipped off to form an exhaust chip off portion. When exhaust is exhausted through an exhaust pipe formed at one end of the hermetic container, especially when the hermetic container is as long as 1 m or longer, there is a tendency that the time is somewhat longer for sufficient exhaust. Therefore, if necessary, a pair of exhaust pipes may be formed in the vicinity of both ends of the hermetic container, and exhaust may be performed simultaneously. Therefore, in this case, a pair of exhaust tip-off portions is formed.
[0018]
In addition, if the airtight container is tubular, it may be slightly curved as well as a straight straight pipe. In practice, a slight curve is likely to be formed when the elongated tube is formed. For example, a curve of about 1 mm or less can be formed for a total length of about 1200 mm. However, this degree of bending is allowed as being almost straight. In addition, when the airtight container is curved in an arc shape as described above, the back portion of the arc is preferably disposed so as to face the external electrode. Moreover, you may arrange | position so that the part of the side surface of a circular arc may be opposed to an external electrode. Therefore, by controlling the arrangement of the external electrodes so that the external electrodes are opposed to each other within an arbitrary angle range as described above, it is possible to obtain a good pressure contact between the external electrode and the outer surface of the hermetic container. In addition, although the cross-sectional shape of a pipe is generally circular, a desired cross-sectional shape such as an ellipse or a quadrangle can be adopted if necessary.
[0019]
    (About the internal electrode)If it is sealed inside the airtight container and powered from one end of the airtight container,Any configuration may be used. For example, a large number of unit mesh portions may have a mesh shape in which the airtight container is arranged in the axial direction through gaps, or internal electrodes having various configurations as in the prior art described above may be adopted as desired. Is allowed. However, since the internal electrode has a mesh shape, the amount of ultraviolet rays generated can be relatively increased, which is preferable. Note that “a large number of unit mesh portions are in the form of meshes arranged with gaps in the axial direction of the airtight container” means that the unit mesh portions are close to the inner wall surface of the airtight container and are airtight. Although it is spatially separated from each other in the axial direction of the container, it refers to a state where it is electrically connected. In addition, the unit mesh part may be continuous with respect to the circumferential direction, or may be divided. Therefore, specifically, the unit mesh portion is allowed to have, for example, a ring shape (the former mode), a spiral shape or a coil shape (the latter mode), or a mesh shape. In the case of a mesh shape, the former or the latter belongs to the configuration of the mesh.
[0020]
When the unit mesh portion has a ring shape, a plurality of unit mesh portions are connected at a predetermined pitch by providing a connecting portion extending in the axial direction of the hermetic container, and conductively Can be connected. In addition, by configuring the connecting portion so as to extend along the central axis of the hermetic container, the internal electrode as a whole is a filament for a copying halogen bulb having a large number of ring anchors (corresponding to unit mesh portions). Thus, the manufacturing equipment can be diverted and the manufacturing becomes easy. However, if necessary, a configuration in which the central axis of the hermetic container is removed and the connecting portion is directly connected to the ring portion of the mesh-like portion may be employed. The connecting portion may be a single straight line or may have a coil shape whose outer diameter is 20% or less with respect to the inner diameter of the airtight container. Further, the connecting portion can be sealed in a state where an appropriate value of tension, preferably 2 kg or more, acts in the direction of the central axis. In order to apply the tension, it is convenient to form the internal electrode in a coil shape. Even if it is not coiled, tension in the central axis direction can be applied to the connecting portion. Regardless of the shape of the connecting portion, it is easy to apply tension to the connecting portion by sealing the both ends of the connecting portion to both ends of the airtight container. However, if necessary, the connecting portion is sealed to only one side of the hermetic container at one end, and the other end is fixed to the sealing portion by an appropriate means such as an anchor wire at the other end of the hermetic container. It is also possible to apply tension to the.
[0021]
On the other hand, when the unit mesh portion has a spiral shape or a mesh shape, the spiral or mesh portion also functions as a connecting portion, so that many unit mesh portions are mechanically and conductively connected to each other. Link. However, the shape retention of the internal electrode can be further imparted by welding a connecting portion made of a single or a plurality of rod-like bodies to a spiral or mesh unit mesh portion. Alternatively, when a spiral or mesh unit mesh portion is formed using a winding frame instead of the connecting portion of the rod-shaped body, the shape retention is improved. Note that the winding frame may be either insulating or conductive. If any of the above-described configurations is adopted for the mesh-like portion, the shape of the internal electrode can be given stability and the handling thereof can be facilitated.
[0022]
Further, the internal electrode is configured such that a product P · P of a pitch P (m) with respect to the axial direction of the unit mesh portion and a pressure p (Pa) of the excimer generation gas described later is within a predetermined range. .
[0023]
Furthermore, in the present invention, the distance between the unit mesh portion and the inner wall surface of the hermetic container is set to 3 mm or less even when the excimer generation gas sealing pressure is increased and the lamp efficiency is improved as described later. can do. If the distance is 3 mm or less, the discharge sustaining voltage can be suppressed to 1000 V or less under certain conditions.
[0024]
Furthermore, the material constituting the internal electrode is not particularly limited. For example, a refractory metal such as tungsten, molybdenum and nickel may be used. However, tungsten and nickel have a relatively small work function and are likely to emit electrons. Therefore, it is effective in reducing the starting voltage.
[0025]
Furthermore, in order to seal the internal electrode to the end of an airtight container made of quartz glass, it is possible to employ a sealing structure using a sealing metal foil that is often used when sealing the quartz glass in a compact manner. it can. Moreover, the sealing metal foil can be hermetically sealed by pinch sealing quartz glass.
[0026]
(Excimer production gas) Excimer production gas is a mixture of one or more kinds of rare gases such as xenon, krypton, argon or helium, or a mixed gas of rare gas and halogen such as fluorine, chlorine, bromine or iodine, for example, XeCl, KrCl. Etc. can be used. Further, in addition to the excimer-generating gas, a gas that does not generate excimer, such as neon, may be mixed and used.
[0027]
Furthermore, the pressure of the excimer product gas can be set to 20000 Pa or more. As the pressure increases, the lamp efficiency improves and the UV output increases. However, the lamp efficiency tends to saturate with increasing pressure.
[0028]
    (External electrode) The external electrode is connected to the outer surface of the hermetic vessel with respect to the gas tight vessel of the dielectric barrier discharge lamp, the excimer forming gas and the arc tube equipped with the internal electrode.Along its axial directionAttached. The mode of attachment may be either a detachable mode or a non-detachable mode. Then, a dielectric barrier that uses the wall surface of the hermetic container as a dielectric between the inner electrode sealed inside the hermetic container.YaIt acts to cause discharge inside the airtight container.In addition, power supply to the external electrode is performed from the other end side of the hermetic container. Therefore, power supply to the dielectric barrier discharge lamp is performed separately on both ends of the hermetic container.
[0029]
  The external electrode has a length in the tube axis direction so as to face the internal electrode. Then, dielectric variability along the tube axis direction of the arc tube.YaDischarge can occur. Note that the width of the external electrode in the direction perpendicular to the tube axis is generally preferably in the range of about 60 to 300 ° at an angle centered on the tube axis of the hermetic container. Accordingly, the portion where the hermetic container of the arc tube is exposed to the outside without the external electrode is formed in a range of about 300 to 60 °, and the ultraviolet rays transmitted through the wall surface of the hermetic container are exposed. Irradiation from a portion to the outside and over a relatively long distance along the tube axis direction of the arc tube can be used for various purposes. However, dielectric burrsYaIn order to radiate as much ultraviolet rays as possible by discharge and to irradiate the emitted ultraviolet rays at a preferable angle, the width in the direction perpendicular to the tube axis of the external electrode is preferably within a range of about 90 to 240 °. There should be. Further, in order to obtain high ease of attachment / detachment of the external electrode and strong pressure contact with the outer surface of the airtight container under the action of the spring force by the support means, it is preferable to be within a range of about 240 ° or less. Therefore, in order to satisfy both the detachability of the external electrode and the radiation of ultraviolet rays, the range of about 60 to 240 ° is optimal.
[0030]
Further, when the external electrode is detachably attached to the outer surface of the hermetic container, the external electrode may be a thin and flexible conductive metal foil, plate or metal wire, or may be a thick rigid body. May be. In either case, the inner surface of the external electrode facing the hermetic container acts as a reflecting means if the reflectance to ultraviolet rays is high, and is effective in increasing the amount of ultraviolet rays that can be taken out to the outside. As a material having a high ultraviolet reflectance, for example, high-purity aluminum or silver can be used. When the external electrode is made of a rigid body, it can be used that functions also as a lamp.
[0031]
Furthermore, the external electrode may be in a continuous planar state or mesh state. The mesh shape means that a large number of unit mesh portions are respectively arranged in the axial direction of the hermetic container via gaps, and the unit mesh portion approaches the inner wall surface of the hermetic container, and further in the axial direction of the hermetic container. A state where they are spatially separated from each other but are electrically connected. Moreover, the unit mesh part may be continuous with respect to the circumferential direction, or may be divided. Therefore, the unit mesh portion is specifically allowed to have a mesh shape, for example.
[0032]
  <Multiple dielectric burrsYaDischarge lamp arrangement> Multiple dielectric burrsYaDischarge lamp has internal electrodesAnd external electrodesAgainsteachThe feeding ends are arranged so as to be adjacent to each other. In the present invention, “internal electrode”And external electrodesAgainsteach`` Feed ends are alternately adjacent '' means that dielectricYaOne discharge lampTwo separated on both ends of the airtight containerThis means that the power feeding end includes not only a mode in which the power feeding ends are alternately distributed to the left and right end portions but also a mode in which a plurality of units are distributed. This is because the former mode can finely level the ultraviolet illuminance, but even the latter mode can achieve leveling in an integral sense.
[0033]
  In addition, dielectric burrsYaThe number of discharge lamps is preferably equal to the number assigned to the left and right. However, dielectric burrsYaIf the number of discharge lamps is to some extent, for example, 9 or more, the difference between the left and right is reduced, so that an odd number may be used.
[0034]
<About the effect | action of this invention> In this invention, the objective of the invention can be achieved by having comprised the structure demonstrated above.
[0035]
  That is, this kind of dielectricYaIn a discharge lamp, the closer to the feed end of the internal electrode, the dielectricYaSince a strong discharge occurs, the longitudinal direction of the internal electrode, and hence the dielectricYaAlong the tube axis of the discharge lampInternal electrodeThere is a tendency that the ultraviolet illuminance decreases from the feeding end toward the non-feeding end.
[0036]
  On the other hand, according to the present invention, the dielectricYaDischarge lampFor internal and external electrodesThe feeding end ofSeparated at both ends of the hermetic vessel and between adjacent dielectric barrier discharge lampsSince a plurality of them are arranged side by side in the left-right direction, it is preferable that the number is an even number in order to improve the uniformity of the higher ultraviolet illuminance. However, dielectric burrsYaIs moved relative to the tube axis in a direction perpendicular to the tube axis, the amount of UV irradiation to the workpiece is leveled along the tube axis direction. Dielectric burrsYaIf the number of ultraviolet discharge lamps is nine or more, the number of discharge lamps may be an odd number in that degree because the difference between the left and right is reduced.
[0037]
    <About other configurations>
  Although not an essential component of the present invention, the following configurations can be selectively added as desired.
1 (Lamp socket) Dielectric barrier discharge lampSalaryIn order to facilitate electricity, lamp sockets having a suitable shape and structure can be attached to both ends of the hermetic container. The arc tube can be supported by the support means via the lamp socket.
2 (Regarding Support Means) The support means is means for supporting both ends of the hermetic container of the dielectric barrier discharge lamp. Further, the dielectric barrier discharge lamp can be supported by interposing a spring force in the support means. Accordingly, it becomes easy to press the airtight container and the external electrode attached to the outer surface thereof with each other by applying a spring force. The spring force is configured to act on at least one end of the hermetic container, preferably on both ends. The specific means for applying the spring force is not particularly limited. For example, the hermetic container can be supported via a spring. Further, it is allowed to use a support means including a support portion supported by the hermetic container and a spring portion that applies a spring force in parallel with the support portion.
[0038]
In the case of support means for supporting the hermetic container via a spring, the support means has a spring interposed between the fixing portion and the hermetic container. The spring can be used by processing a spring material made into a plate shape or a rod shape into various structures and shapes. In the case where the external electrode is pressed against the outer surface of the hermetic container by applying a spring force over the entire length of the hermetic container while supporting means for applying the spring force is provided at one end of the hermetic container, one end of the hermetic container is supported by a hinge. The other end can be attached to the fixed portion by a supporting means for applying a spring force.
[0039]
  In order to press the external electrode against the outer surface of the hermetic container, a lamp body having rigidity extending along the longitudinal direction of the hermetic container can be used as a fixing portion. Then, the airtight container can be pressed against the lamp body, and the external electrode can be sandwiched between the lamp body and the airtight container at that time, so that the external electrode is brought into close contact with the outer surface of the airtight container. convenient. In such an embodiment, the external electrode can be formed of a flexible member, and a relatively inexpensive external electrode can be easily obtained by using a member having high ultraviolet reflectivity. Further, by providing an appropriate cooling means in the lamp body, it is effective to remove heat from the airtight container via the external electrode and to keep the ultraviolet radiation efficiency high. As a cooling means, a cooling medium, such as water, can be passed through the lamp body.
3 (About the lamp) The lamp is made of a heat conductive material such as aluminum or stainless steel, and there is a dielectricYaSince the discharge lamp is attached to the heat conduction state,YaIt can be used as a means for removing heat generated by lighting of the discharge lamp. In order to strengthen the action of such a lamp, the lamp can be forcibly cooled. For example, a cooling medium such as water can be passed through the inside or outside of the lamp body. Or, the outer surface of the lamp body is unevenInThus, a known cooling means can be used as appropriate, such as making the structure easy to dissipate heat and / or using a fan device that forcibly passes air.
[0040]
  In addition, the dielectricYaBy attaching a discharge lamp,YaIt becomes easier to support the discharge lamp. Therefore, if necessary, support means described later can be used.
[0041]
  In addition, dielectric burrs on the lampYaBy attaching the discharge lamp, the external electrode can be sandwiched between the airtight container and the lamp body as desired, and the external electrode can be easily pressed against the outer surface of the airtight container. For this purpose, support means described later can be used.
[0042]
A dielectric barrier discharge lamp illuminating device according to a second aspect of the present invention includes a dielectric barrier discharge lamp, and a dielectric barrier discharge lamp provided therein with a cooling medium flow path leading from an inlet on one end side to an outlet on the other end side. A plurality of dielectric barrier discharge lamp units having elongated lamp bodies attached in the longitudinal direction of the lamp body are arranged in parallel so that the cooling medium inlets of the lamp bodies are alternately adjacent to each other. ing.
[0043]
In the present invention, a single dielectric barrier discharge lamp is allowed to have the structure described in the invention of claim 1.
[0044]
In addition to the structure described in the first aspect of the invention, the lamp body is allowed to have a cooling medium flow path inside, and an inlet of the cooling medium is provided at one end side of the lamp body, and the other end side. An outlet is formed in each. The cooling medium flow path may be formed inside the lamp body, for example, through the lamp body, or a pipe-shaped cooling medium flow path is welded to the outer surface of the lamp body by welding or the like. You may form by attaching.
[0045]
The lamp body and a single dielectric barrier discharge lamp are combined to form a dielectric barrier discharge lamp unit. However, a larger number of dielectric barrier discharge lamp units are arranged at as short intervals as possible and required within a small area. In order to ensure a sufficient amount of ultraviolet light, the width of the lamp should be relatively narrow. Preferably, it is about 120 to 200% with respect to the maximum width of the dielectric barrier discharge lamp.
[0046]
  The plurality of dielectric barrier discharge lamp units are arranged so that the inlets of the cooling medium passages of the lamp body are alternately adjacent to each other. In the present invention, “the inlets are alternately adjacent” means a dielectric barrier.YaThis means that not only the discharge lamp unit is a single unit and the inflow ports are alternately distributed to the left and right end portions, but also includes a mode in which a plurality of discharge lamp units are distributed. This is because the former mode can finely level the ultraviolet illuminance, but even the latter mode can achieve leveling in an integral sense.
[0047]
  In addition, dielectric burrsYaThe number of discharge lamps is preferably equal to the number assigned to the left and right, that is, an even number is preferable in order to improve the uniformity of the ultraviolet illuminance. However, dielectric burrsYaIf the number of discharge lamps is to some extent, for example, 9 or more, the difference between the left and right is reduced, so that an odd number may be used.
[0048]
Thus, in the present invention, the intended object of the invention can be achieved by having the configuration described above.
[0049]
  That is, this kind of dielectricYaIn the discharge lamp, the luminous efficiency decreases as the temperature rises. In addition, the temperature of the lamp gradually increases from the cooling medium inlet to the outlet. Therefore, dielectric burrsYaThere is a tendency that the ultraviolet illuminance decreases from the inlet to the outlet along the tube axis direction of the discharge lamp.
[0050]
On the other hand, according to the present invention, as described above, since the inflow ports of the lamp body are distributed to the left and right ends and arranged in parallel, the work to be irradiated with ultraviolet rays is perpendicular to the tube axis. In the case of relative movement, the amount of ultraviolet irradiation to the work is leveled along the tube axis direction.
[0051]
According to a third aspect of the present invention, there is provided an ultraviolet irradiation apparatus according to the first or second aspect; an ultraviolet irradiation apparatus main body provided with the dielectric barrier discharge lamp apparatus; and lighting the dielectric barrier discharge lamp apparatus. And a high-frequency lighting circuit.
[0052]
In the present invention, the “ultraviolet irradiation device” means any device that uses ultraviolet rays generated from a dielectric barrier discharge lamp device. For example, 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 part of the ultraviolet irradiation device excluding the dielectric barrier discharge lamp device and the high frequency generation means.
[0053]
Further, one or more dielectric barrier discharge lamp devices can be used as required.
[0054]
Furthermore, a high frequency lighting circuit is used to light the dielectric barrier discharge lamp device. The high-frequency lighting circuit includes high-frequency generating means, generates a high-frequency voltage, and supplies the dielectric barrier discharge lamp device with high-frequency power necessary for the lighting. “High frequency” refers to a frequency of 10 kHz or more. However, it is preferably 100 kHz to 2 MHz. The high-frequency lighting circuit preferably applies a high-frequency voltage of about 1500 V or less, preferably 700 to 1000 V, when the dielectric barrier discharge lamp device is stably lit. Furthermore, the starting voltage of the dielectric barrier discharge lamp device is 2 to 2.3 kVp-p, and can be easily started by increasing the secondary open voltage of the high-frequency lighting circuit to the starting voltage. In this case, it is preferable to use a parallel inverter as a main component as the high-frequency generating means because a high step-up ratio can be easily obtained. Since the high-frequency output waveform is a sine wave, noise generation is reduced when the dielectric barrier discharge lamp device is turned on. However, if necessary, the starting pulse voltage generating means can be used together with the high frequency generating means. Furthermore, the dielectric barrier discharge lamp device and the high-frequency lighting circuit are preferably arranged at close positions, but can be arranged at positions separated from each other if necessary. Unlike a general discharge lamp, the dielectric barrier discharge lamp device does not need to connect current limiting means in series. However, in order to adjust the lamp current to a predetermined value, lighting with an appropriate value of impedance connected in series can be performed as necessary. Further, when the dielectric barrier discharge lamp device is connected to the high-frequency lighting circuit, if the external electrode is grounded, noise generation is reduced.
[0055]
In dielectric barrier discharge when the internal electrode has a mesh-like configuration and is an anode and the external electrode is a cathode, there is a lot of ultraviolet radiation from the vicinity of the unit mesh part of the internal electrode, and the adjacent unit mesh Less UV radiation from the middle of the part. Therefore, it was found that when the pitch of the unit mesh portion is large, the degree of uniformity of the ultraviolet illuminance in the axial direction of the hermetic container deteriorates and the ultraviolet illuminance also decreases. In addition, when the phase of an internal electrode and an external electrode is reverse, it does not become above. If the pitch of the unit mesh portion of the internal electrode is 4 mm or less, the valley portion where the ultraviolet illuminance between the unit mesh portions is reduced is filled with the region having a high ultraviolet intensity generated by each unit mesh portion, and as a result, airtight The uniformity of the ultraviolet illuminance in the axial direction of the container is remarkably improved and the ultraviolet illuminance is improved.
[0056]
In addition, since strong afterglow light emission is generated by pulse lighting, it contributes to the improvement of ultraviolet illuminance.
[0057]
The high-frequency lighting circuit 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. However, the configuration may be such that a sine wave pulse is obtained using an inverter having a sine wave output.
[0058]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0059]
1 to 8 show a first embodiment of a dielectric barrier discharge lamp illuminating device according to the present invention, and FIG. 1 is a conceptual diagram for explaining the arrangement and power supply modes of a plurality of dielectric barrier discharge lamps. 2 is a partially cutaway front view and left and right side views of a dielectric barrier discharge lamp, FIG. 3 is a front view of an arc tube, FIG. 4 is a front sectional view of an enlarged main portion, and FIG. FIG. 6 is a sectional view taken along the line VI-VI ′ of FIG. 5, FIG. 7 is an enlarged longitudinal sectional view of the lamp body, and FIG. 8 is a right side view of the same.
[0060]
In each figure, the dielectric barrier discharge lamp illumination device EXF has a plurality of dielectric barrier discharge lamp units EU in FIG. Each dielectric barrier discharge lamp unit EU is composed of a combination of a single dielectric barrier discharge lamp EXL and a lamp body CB. The dielectric barrier discharge lamp EXL has a total length of 1295 mm and an effective light emission length of 1130 mm. Hereinafter, each component will be described.
[0061]
  <Regarding Dielectric Barrier Discharge Lamp EXL> In the present embodiment, the dielectric barrier discharge lamp EXL includes an arc tube LT, an external electrode OE,Internal electrodeA lamp socket LS1 on the power supply end side, first support means SS1,External electrodeThe lamp socket LS2 on the power feeding end side and the second support means SS2 are provided. In the figure, T is a voltage side power supply terminal block.
[0062]
(Regarding the arc tube LT) As shown in FIG. 3, the arc tube LT includes an airtight container 1, an excimer forming gas, an internal electrode 2, and a pair of lead wires 3, 4.
[0063]
The hermetic container 1 includes an elongated cylindrical hollow portion 1a having an overall length of about 1200 mm and made of an ultraviolet light transmissive material having an outer diameter of 18 mm and an inner diameter of 16 mm, and sealing portions 1b formed at both ends of the hollow portion 1a. ing. The sealing portion 1b has a pinch seal structure in which a molybdenum foil 1b1 is embedded. Further, an exhaust tip off portion 1c projects from the side surface in the vicinity of one end of the hollow portion 1a. The exhaust tip off portion 1c is formed at a position 40 mm from one end of the airtight container 1.
[0064]
Xenon is enclosed in the hollow portion 1a of the hermetic container 1 as an excimer production gas.
[0065]
The internal electrode 2 includes a connecting portion 2a, a large number of unit mesh portions 2b, and both end straight portions 2c. The connecting portion 2a is mainly composed of a coil 2a having an outer diameter of 1.2 mm formed by winding a thin metal wire made of a tungsten wire having a wire diameter of 0.26 mm. The unit mesh portion 2b is made up of a large number of ring-shaped anchors arranged on the connecting portion 2a at a constant pitch of, for example, 15 mm. Both end straight portions 2c are formed by extending both ends of the connecting portion 2a. And the internal electrode 2 welds the both-ends linear part 2c to the end of the molybdenum foil 1b1 of the sealing part 1b formed in the both ends of the airtight container 1, in the state which acted about 2 kg of tension. The connecting portion 2 a of the internal electrode 2 is extended by the action of tension while being mounted in the airtight container 1.
[0066]
The pair of lead-in wires 3 and 4 are welded to the molybdenum foil 1b1 embedded in the sealing part 1b formed at both ends of the hermetic container 1, and the base ends are exposed to the outside from the sealing part 1b. Yes. However, since the lead-in wire 4 is on the non-power feeding side, the externally exposed portion is cut after the hermetic container 1 is sealed, and the lead wire 4 is short. In addition, if necessary, a heat-resistant insulator can be applied to conceal the exposed portion after cutting the lead-in wire 4.
[0067]
    (External Electrode OE) The external electrode OE includes an electrode main part 11, a reinforcing ring part 12, and a packing 13, as mainly shown in FIG. The electrode main part 11 is formed of a high-purity aluminum plate formed so as to have an opening angle of about 220 ° in the cross section and is formed in a bowl-like body that is curved in a substantially arc shape, and the inside of the airtight container 1 of the arc tube LT. It is fitted to the outer surface of the hermetic container 1 over almost the entire length of the region facing the electrode 2. The reinforcing ring portion 12 is made of a conductive metal, one end overlaps the end portion of the electrode main portion 11 from above, and the other end side will be described later.Internal electrodeIt is inserted into the opening of the lamp socket LS1 on the power supply end side. The packing 13 is interposed between the reinforcing ring portion 12 and the outer surface facing the airtight container 1,Internal electrodeThe inside of the lamp socket LSI on the power supply end side is sealed waterproof and moisture-proof.
[0068]
    (Internal electrodeAbout the lamp socket LS1 on the feeding end side)Internal electrodeThe lamp socket LS1 on the power supply end side has a function of supplying power to the internal electrode 2 of the arc tube LT as mainly shown in FIG. 4, and includes a socket cylinder 14, a tightening ring portion 15, a wire harness. 16, an insulating disk 17 and an insulating protection part 18. The socket cylinder 14 has a bottomed cylindrical shape and encloses the end portion of the arc tube LT on the power feeding side. A small opening is provided at the center of the bottom. The tightening ring portion 15 is conductively and mechanically fixed to the opening of the socket tube body 14, and tightens the end portion on the power feeding side of the arc tube LT via the reinforcing ring portion 12 and the packing 13 of the external electrode OE. Fix to the socket cylinder 14.
[0069]
The wire harness 16 electrically connects the lead-in wire 3 led out from the arc tube LT and a mounting / terminal device 23 described later. The insulating disk 17 is made of a ceramic disk having a relatively small opening in the center, and insulates the wire harness 16 introduced from the bottom of the socket cylinder 14 via the opening from the socket cylinder 14. The insulation protection unit 18 is made of a ceramic cylindrical body, and holds the wire harness 16 introduced into the socket cylindrical body 14 in an insulating manner while being fixed by being inserted therein.
[0070]
    (Regarding the first support means SS1) The first support means SS1, as shown mainly in FIG.Internal electrodeThe lamp socket LS1 on the power supply end side is supported. The insulating joint 19, the leaf spring 20, the first arm 21, the second arm 22, the attachment / terminal device 23, and the like.
[0071]
One end of the insulating joint 19 is fixed to the tip of the second arm 22, and a coupling plate 19 a protrudes from the other end. The coupling plate 19a is insulated from the second arm 22.
[0072]
  The leaf spring 20 is L-shaped as a whole, and a spring force applying portion 20a that is curved is formed in the middle portion. Further, one end of the leaf spring 20 is connected via the insulating joint 19 and the second arm 22.Internal electrodeIt is insulatively connected to the socket cylinder 14 of the lamp socket LS1 on the power supply end side. Further, the other end of the leaf spring 20 is fixed to the attachment / terminal device 23.
[0073]
The base end of the first arm 21 is welded to the rear end portion of the socket cylinder 14, and the insulation protection portion 18 of the lamp socket LS 1 on the power supply end side is fixed to the socket cylinder 14.
[0074]
  The second arm 22 has a proximal end mainly as shown in FIG.Internal electrodeIt is welded to the front end of the socket cylinder 14 of the lamp socket LS1 on the power supply end side.
[0075]
  The mounting / terminal device 23 is coupled to the socket cylinder 15 at a position separated from the socket cylinder 15, and the arc tube LT and the external electrode OE are connected to the socket cylinder 15.Internal electrodeIt also functions to apply and fix a spring force via the lamp socket LS1 on the power supply side and the first support means SS1. In addition, an attachment / terminal fitting 23a, a bolt / nut 23b, and an attachment screw 23c are provided. One end of the mounting / terminal fitting 23a is connected to the leaf spring 20 and the wire harness 16 by a bolt / nut 23b. Further, the other end is attached to the voltage-side power terminal block T by the attachment screw 23c, for example, in a suspended state as shown in the figure. Bolts and nuts 23bInternal electrodeThe power supply end of the dielectric barrier discharge lamp device EXL is supported via the lamp socket LS1 on the power supply end side, and also functions as a terminal fitting. Its plate surface extends substantially parallel to the dielectric barrier discharge lamp device EXL. Exist. The bolt / nut 23b mechanically and electrically connects the other end of the wire harness 16 to the mounting / terminal fitting 23a together with the leaf spring 20.
[0076]
    (External electrodeAbout the lamp socket LS2 on the power supply end side)External electrodeAs shown in FIG. 5, the lamp socket LS2 on the feeding end side is roughlyInternal electrodeThe structure is similar to the lamp socket LS1 at the power supply end, but power is not supplied to the internal electrode 2 and the external electrode OE is grounded.To supply power to the external electrode OEThe socket cylinder 30, the tightening ring portion 31, and the insulating disk 32 are configured.
[0077]
  The socket cylinder 30 has a bottomed cylindrical shape,The other end of the airtight container 1, that is, the external electrode OEHold the power supply end.
[0078]
  As shown in FIG. 6, the tightening ring portion 31 has a split structure, and by screwing a pair of tightening screws 31 a, external electrodesOEIs electrically and mechanically connected to the opening of the socket cylinder 30;Airtight container 1ofotherThe end is tightened and fixed to the socket cylinder 30.
[0079]
The insulating disk 32 is disposed on the inner surface of the bottom of the socket tube 30 and insulates the lead wire 4 connected to the internal electrode 2 of the arc tube LT from the socket tube 30 that is grounded.
[0080]
  (Regarding the second support means SS2) The second support means SS2, as shown mainly in FIG.External electrodeThe lamp socket LS2 on the power supply end side is supported. The mounting / terminal device 35, the leaf spring 36 and the arm 37 are included.
[0081]
  The mounting / terminal device 35 includes a mounting / terminal fitting 35a, a screw 35b, and a mounting screw 35c. Mounting / terminal fitting 35aExternal electrodeThe external electrode OE of the dielectric barrier discharge lamp device EXL is electrically connected to a ground power source terminal block (not shown) via the lamp socket LS2 on the power supply end side, and at the same time, the dielectric barrier discharge lamp device EXLExternal electrodeThe power supply end is supported, and the plate surface thereof extends substantially parallel to the dielectric barrier discharge lamp device EXL. The screw 35b connects the leaf spring 36 to one end of the mounting / terminal fitting 35a. The attachment screw 35c mechanically and electrically attaches the other end of the attachment / terminal fitting 35a to a ground power terminal block (not shown).
[0082]
The leaf spring 36 is L-shaped as a whole, and a spring force applying portion 36a that is curved is formed in the middle portion. One end of the leaf spring 36 is connected via an arm 37 to the socket cylinder 30 of the lamp socket LS2 on the non-power feeding end side. The other end of the leaf spring 36 is fixed to the mounting / terminal fitting 35a by a terminal screw 35b. The base end of the arm 37 is welded to the front end portion of the socket cylinder 30.
[0083]
The arm 37 has a proximal end welded to the socket cylinder 30 and a distal end connected to the leaf spring 36.
[0084]
<Regarding Lamp CB> As shown in FIGS. 7 and 8, the lamp CB is elongated along the arc tube LT and has a semicircular recess having a semicircular cross section in which about half of the airtight container 1 is embedded in the lower surface. A portion 40 is formed, and a hollow coolant flow path 41 is formed inside. The cooling medium flow passage 41 is configured to flow in from an inflow port 41a disposed on one end side of the lamp body CB and to flow out from an outflow port (not shown) disposed on the other end side. . The lamp body CB has a length opposite to the effective light emission length of the arc tube LT. And the exhaust tip off part 1c is arrange | positioned in the position exposed from the end of the lamp body CB. The exhaust tip-off part 1 c may be arranged at an arbitrary angular position on the outer periphery of the airtight container 1.
[0085]
  <Multiple dielectric burrsYaRegarding arrangement of discharge lamp unit Eu> Plural dielectric burrsYaThe discharge lamp unit Eu is a dielectric burrYaFeeding end for internal electrode of discharge lamp EXLAnd the feeding end for the external electrodeButIt is divided into both ends of the hermetic vessel, and between the adjacent dielectric barrier discharge lamps EXL, the feeding end of the internal electrode and the feeding end of the external electrode areThey are arranged so as to be alternately located on the left and right. That is, in FIG. 1, the first and third internal electrode feed ends from the top are on the right side of FIG.External electrodeThe feeding end is on the left side of Fig. 1.groundIt is drawn as it is. In contrast, the second and fourth from the top of FIG.Internal electrodeThe feeding end is located on the left side of FIG. Each internal electrode feed end hasRespectivelyOne pole of the high-frequency power source S is connected. Also,eachThe other pole of the high-frequency power source S andEach external electrode feed endIs groundedIs connected electrically.
[0086]
FIG. 9 is a conceptual diagram for explaining the arrangement of a plurality of dielectric barrier discharge lamps and the flow mode of the cooling medium in the second embodiment of the dielectric barrier discharge lamp illumination device of the present invention. In the present embodiment, the inflow ports 41a and the outflow ports 41b that are distributed and arranged on both ends of the back surface of the lamp body CB are arranged so as to be alternately arranged on the left and right. That is, in FIG. 9, the first and third inflow ports 41a from the top are depicted on the right side of FIG. 9, and the outflow port 41b is depicted on the left side of FIG. On the other hand, in the second and fourth from the top of FIG. 9, the inlet 41a is located on the left side of FIG. In the figure, the arrows indicate the flow direction of the cooling medium.
[0087]
10 to 12 show an ultraviolet cleaning apparatus as an embodiment of the ultraviolet irradiation apparatus of the present invention. FIG. 10 is a front sectional view, FIG. 11 is a bottom view, and FIG. 12 is a line XX 'in FIG. FIG. In each figure, the same parts as those in FIGS. 1 to 8 are denoted by the same reference numerals, and description thereof is omitted. The ultraviolet irradiation device UVW includes an ultraviolet irradiation device main body 51, a lighting circuit 52, and a dielectric barrier discharge lamp illumination device EXF.
[0088]
The ultraviolet irradiation device main body 51 has a box shape as a whole, and the interior is divided into an ultraviolet irradiation chamber 51a and a power supply chamber 51b in the vertical direction. The ultraviolet irradiation chamber 51a and the power supply chamber 51b are configured such that one end thereof can be opened and closed by a hinge 51c.
[0089]
In the ultraviolet irradiation chamber 51a, a dielectric barrier discharge lamp illumination device EXF is disposed as will be described later. The ultraviolet irradiation chamber 51a is fixedly disposed on the upper part of the conveying means of the workpiece cleaning device, and the lower surface is opened, and the workpiece (not shown) passing under the lower surface is irradiated with ultraviolet rays. It is supposed to be. In FIG. 11, the hatched portion indicates the effective ultraviolet irradiation region.
[0090]
The power supply chamber 51b houses therein a lighting circuit 52 and a control circuit (not shown), and is rotatable upward in FIG. 10 with a hinge 51c as a rotation center. In addition, 51b1 is a handle for gripping the power supply chamber 51b during rotation, 51b2 is a handle for transporting the ultraviolet irradiation apparatus main body 51 or the power supply chamber 51b, and 51b3 is a protector for the power supply wiring.
[0091]
The lighting circuit 52 is housed in the power supply chamber 51b, converts a power supply introduced into the power supply chamber 51b via a power supply wiring protector 51b3, generates a high frequency voltage, and a plurality of dielectric barrier discharge lamp devices. Power is supplied to each dielectric barrier discharge lamp EXL of the unit EX.
[0092]
The plurality of dielectric barrier discharge lamp units EU are arranged adjacent to each other in the ultraviolet irradiation chamber 51a. However, each of the required dielectric barrier discharge lamp device units EX can be attached and detached for ease of manufacture and maintenance.
[0093]
Also, in order to allow the cooling water to flow through the cooling medium flow passage of the lamp CB, a pipe for supplying cooling water is connected to the inlet, and a pipe for drainage is connected to the outlet. Yes.
[0094]
【The invention's effect】
    According to the first aspect of the present invention, an elongated tubular airtight container made of an ultraviolet light transmissive material, sealed in the airtight container along its axial direction.Airtight containerAn internal electrode fed from one end, an excimer-generating gas sealed in an airtight container, and an outer surface of the airtight containerAlong its axial directionAttachedPower is supplied from the other end of the airtight container.Dielectric burrs in the airtight container through cooperation with internal electrodesYaA plurality of dielectric barrier discharge lamps having external electrodes that act to cause discharge,And external electrodesAgainsteachBy arranging the feeding ends in parallel so that they are alternately adjacent to each other, the work to be irradiated with ultraviolet rays is relatively perpendicular to the tube axis in a state where a plurality of dielectric barrier discharge lamps are arranged in parallel. Therefore, it is possible to provide a dielectric barrier discharge lamp illuminating device in which the amount of ultraviolet irradiation with respect to the workpiece is leveled along the tube axis direction.
[0095]
According to the second aspect of the present invention, the dielectric barrier discharge lamp and the cooling medium flow path leading from the inlet on one end side to the outlet on the other end are provided in the length direction of the dielectric barrier discharge lamp. A plurality of dielectric barrier discharge lamp units having elongated lamp bodies in contact with each other are arranged in parallel so that the cooling medium inlets of the lamp bodies are alternately adjacent to each other. It is possible to provide a dielectric barrier discharge lamp illuminating device in which the amount of ultraviolet irradiation with respect to the workpiece is leveled along the tube axis direction when moved relative to the direction perpendicular to the axis.
[0096]
According to a third aspect of the present invention, the dielectric barrier discharge lamp according to the first or second aspect, an ultraviolet irradiation apparatus main body provided with the dielectric barrier discharge lamp, and a high-frequency lighting circuit are provided. An ultraviolet irradiation device having an effect can be provided.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram for explaining the arrangement and power supply modes of a plurality of dielectric barrier discharge lamps according to a first embodiment of a dielectric barrier discharge lamp illumination device of the present invention.
FIG. 2 is a partially cut front view and left and right side views showing a dielectric barrier discharge lamp.
[Figure 3] Front view of arc tube
[Figure 4] SimilarlyThe lamp socket on the inner electrode feeding end side and the first support means;Enlarged main section central section front view
[Figure 5]External electrodeLamp socket on the feeding end side andSecondEnlarged main part center cross-section front view of support means
6 is a cross-sectional view taken along line VI-VI ′ of FIG.
FIG. 7 is an enlarged vertical sectional view of the same lamp.
[Fig. 8] Right side view
FIG. 9 is a conceptual diagram for explaining the arrangement of a plurality of dielectric barrier discharge lamps and the mode of flow of a cooling medium, showing a second embodiment of the dielectric barrier discharge lamp illumination device of the present invention.
FIG. 10 is a front sectional view showing an ultraviolet cleaning apparatus as an embodiment of the ultraviolet irradiation apparatus of the present invention.
FIG. 11 is also a bottom view
12 is a cross-sectional view taken along line XX ′ of FIG.
[Explanation of symbols]
      DESCRIPTION OF SYMBOLS 1 ... Airtight container, CB ... Lamp, EU ... Dielectric barrier discharge lamp unit, EXF ... Dielectric barrier discharge lamp illuminating device, S ... High frequency power supply

Claims (3)

Internal electrodes, excimer generated gas sealed in air tight containers elongated tubular airtight container made of ultraviolet transmitting material, while being FuSo along the axial direction of the airtight container is fed from one end of the airtight container, and external acts to rise to dielectric burrs ya discharge in an airtight container to the outer surface of the airtight container along its axial direction is fed from the other end of the spliced by Rutotomoni airtight container in cooperation with the internal electrode A dielectric barrier discharge lamp illuminating device, wherein a plurality of dielectric barrier discharge lamps having electrodes are arranged in parallel so that respective power supply ends for the internal electrode and the external electrode are alternately adjacent to each other . An elongate tubular hermetic container made of an ultraviolet light transmissive material, an internal electrode sealed along the axial direction in the hermetic container, an excimer generating gas sealed in the hermetic container, and an inner surface attached to the outer surface of the hermetic container A dielectric barrier discharge lamp having an external electrode which acts to generate a dielectric barrier discharge in the hermetic container by cooperating with the electrode, and a cooling medium passing from the inlet at one end to the outlet at the other end. A plurality of dielectric barrier discharge lamp units each having a flow path and a long and narrow lamp body joined in the length direction of the dielectric barrier discharge lamp are arranged in parallel so that the cooling medium inlets of the lamp bodies are alternately adjacent to each other. A dielectric barrier discharge lamp illuminating device characterized in that the device is arranged in a regular manner. A dielectric barrier discharge lamp illumination device according to claim 1 or 2;
An ultraviolet irradiation device body provided with a dielectric barrier discharge lamp illumination device;
A high frequency lighting circuit for lighting a dielectric barrier discharge lamp;
An ultraviolet irradiation device comprising:

Images