JP2001135278A - Dielectric barrier lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric barrier lamp that radiates emission light produced within its emission tube toward the exterior of the light emission tube with stability and high efficiency. SOLUTION: External electrodes 108 are made in close contact with a light- emitting tube 103 by forming a spiral groove 113 and projection 112 on the contact face of the arc tube 103 with a casing 107 disposed at the periphery thereof. Also, the external electrodes 108 are made ion a thin metallic band shape and given a high opening area ratio by forming many openings 111 of arbitrary shapes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp, and more particularly to a dielectric barrier lamp used for an ultraviolet exposure apparatus or the like.

[0002]

2. Description of the Related Art In order to manufacture a semiconductor integrated circuit (IC), a liquid crystal display panel (LCD), a printed circuit board (PCB), and the like, it is common to use a photocurable resin (resin) and an ultraviolet exposure apparatus. is there. In such an exposure apparatus, a mercury lamp, a dielectric barrier lamp, or the like is used.

In a dielectric barrier lamp, a discharge vessel is filled with a discharge gas forming excimer molecules, and excimer molecules are formed by an ozonizer discharge or a dielectric barrier discharge. A lamp for extracting light emitted from the excimer molecule. Conventional examples of such a dielectric barrier lamp are disclosed in JP-A-7-14553 and JP-A-7-1455.
No. 4 and JP-A-6-310104, "Dielectric barrier discharge lamp". As shown in FIG. 5, such a conventional example includes a discharge vessel 1, an inner tube 2, an outer tube 3, electrodes 4, 5, a getter 6, a discharge space 7, a power source 8, and a protrusion 9. Discharge vessel 1 whose external shape is substantially cylindrical
The discharge space 7 is filled with a discharge gas for forming excimer molecules by dielectric barrier discharge. At least a part of the discharge vessel 1 also functions as a dielectric of a dielectric barrier discharge, and at least a part of the discharge gas is transparent to light emitted from excimer molecules. Conductive mesh electrodes 4 and 5 are provided on at least a part of this light-transmitting dielectric to constitute a dielectric barrier discharge lamp. At least one group of the wires forming the conductive mesh electrode is arranged so as to obliquely intersect the axis 10a-10b of the discharge vessel 1.

Another conventional example of a dielectric barrier discharge lamp device is disclosed in, for example, JP-A-8-153493. FIG. 6 shows this conventional example. This dielectric barrier discharge lamp device includes a plurality of dielectric barrier discharge lamps 1 each having the same configuration as the dielectric barrier discharge lamp shown in FIG.
a, 1b, 1c, two V-shaped light reflectors having vertices 12
11, 13, light extraction window 20, lamp house 21, cooling block 22, inert gas inlet 23 such as nitrogen gas, inert gas outlet 24, discharge gas filled space 26, light reflecting plate 27 and cooling fluid It is composed of passages 28 and 29.

[0005] As described above, the light-transmitting discharge vessel having a substantially cylindrical outer shape, the metal mesh electrode provided on the entire outer periphery of a part of the outer surface of the discharge vessel, and the discharge vessel inside the electrode are substantially referred to as the discharge vessel. A plurality of cylindrical dielectric barrier discharge lamps 1a to 1 comprising a coaxial inner electrode and a discharge gas filled in a discharge vessel and forming excimer molecules by dielectric barrier discharge.
c and these plural lamps are arranged in parallel and stored,
This is a dielectric barrier discharge lamp device including a lamp house 21 having a light extraction window 20 for extracting excimer light emitted from excimer molecules, and a power supply for performing dielectric barrier discharge. And the plurality of adjacent lamps described above.
V-shaped light reflectors 11 and 13 are provided between the two to increase the luminous intensity and to obtain relatively uniform parallel light from the light extraction window 20 over a wide range.

[0006]

However, the conventional dielectric barrier discharge lamp described above lacks vibration, shock and thermal stability because a linear external electrode is spirally wound around the outer periphery of the arc tube. . In addition, a sufficient light emission output required for recent exposure apparatuses such as ICs, LCDs, and PCBs cannot be obtained.
Further, when a plurality of dielectric barrier discharge lamps are used, there is a problem that the size becomes large and power consumption increases.

[0007] Accordingly, an object of the present invention is to provide excellent stability,
Another object of the present invention is to provide a dielectric barrier discharge lamp having high luminous efficiency.

[0008]

According to the dielectric barrier lamp of the present invention, a housing is disposed outside the arc tube, and spiral grooves and projections are formed on the inner surface of the housing. Further, a thin metal strip-shaped electrode is used as an external electrode on the outer periphery of the arc tube, which is housed in a helical groove of the housing portion and held tightly on the outer surface of the arc tube.

A large number of openings are formed in a mesh shape in the strip-shaped external electrode, and a high aperture ratio efficiently radiates light emitted from the arc tube to the outside of the arc tube. Also, the internal electrodes are
A metal rod-shaped electrode is inserted into the center hole of the arc tube, and an electrode holder is disposed at least at one end. The high-frequency drive voltage is applied to the internal and external electrodes, preferably via an electrode fixing plate.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure and operation of a preferred embodiment of a dielectric barrier lamp according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view of a preferred embodiment of a dielectric barrier lamp according to the present invention. The configuration of the dielectric barrier lamp 100 will be described. This dielectric barrier lamp 100
Is the conductive metal rod electrode 10 installed at the center of the lamp.
1. It includes a terminal 102 provided on the electrode 101 for applying a high-frequency drive voltage, and an arc tube 103 of a double structure or a coaxial structure arranged around the electrode 102. This arc tube 103
The discharge space sealed by the outer tube and the inner tube
104 is filled with a rare gas such as argon or xenon. This arc tube 103 is made of light (ultraviolet light) such as quartz glass.
It is formed of a transparent material. Insulated electrode holding members 105 and 10 are inserted through the electrode 101 and on both sides of the arc tube 103.
6 are located.

The dielectric barrier lamp 100 further includes a housing 107, a thin metal strip-shaped and spiral external electrode 108 disposed outside the arc tube 103, and an electrode fixing plate 110. Protrusions 112 and grooves 113 for holding the spiral external electrodes 108 are formed alternately on a portion of the housing 107 facing the arc tube 103.

Next, FIGS. 2 and 3 are sectional views of the dielectric barrier lamp 100 according to the present invention shown in FIG. FIG. 4 is a view showing the appearance of the dielectric barrier lamp 100 according to the present invention. As best shown in FIG. 4, the dielectric barrier lamp 100 of the present invention is
Means that a large number of openings 108 are formed in the external electrode 108 arranged and formed on the outer periphery of the arc tube 103. These openings 108
Will be apparent from the following description.

In this dielectric barrier lamp 100, a high-frequency driving voltage is applied between a thin metal external electrode 108 and a central rod-shaped metal internal electrode 101. Since the external electrode 108 and the internal electrode 101 face each other, discharge occurs between the external electrode 108 and the internal electrode 101 by the high-frequency drive voltage applied to the external electrode 108. At this time, it is well known that the wavelength of the emitted light changes depending on the type of the rare gas interposed between the electrodes 108 and 101.

At this time, unless the external electrode 108 is in close contact with the arc tube 103, optimal light emission cannot be maintained.
If the external electrode 108 does not have an appropriate aperture ratio, the emitted light cannot be sufficiently emitted from the light emitting window to the outside. Therefore, generally, the external electrode 108 is relatively spirally wound around the outer periphery of the arc tube 103 so as to obtain a sufficient opening.

According to the dielectric barrier lamp 100 of the present invention, the spiral external electrode 1
Grooves 113 are formed at a pitch into which the holes 08 can be fitted. The groove 113 can press or adhere the thin strip-shaped external electrode 108 of a good conductive metal such as SUS (stainless steel), Monel, or aluminum to the outer surface of the arc tube 103 at a constant pitch. The end of the external electrode 108 is fixed by the fixing plate 110 as described above. Simply winding the strip-shaped external electrode 108 around the outer surface of the arc tube 103 may cause displacement due to vibration, impact, heat generation, or the like. However, according to the dielectric barrier lamp 100 of the present invention, the groove 113 and the protrusion 112 provided in the housing 107 are provided.
Thus, the external electrode 108 can be securely and stably fixed. Moreover, by processing the protrusion 112 to a height that sets the distance between the arc tube 103 and the housing 107, it is possible to keep the thickness of the strip-shaped external electrode 108 constant without impairing it. It is. By appropriately selecting the pitch between the groove 113 and the protrusion 112, the aperture ratio of the external electrode 108 can be determined.

Furthermore, the dielectric barrier lamp 100 of the present invention
According to the width of the metal plate forming the external electrode 108,
Many openings 111 are formed over the entire length. By using the external electrode 108 having such a specific shape, the aperture ratio is greatly increased, and the emitted light can be emitted to the outside extremely efficiently. The opening 111 of the external electrode 108 is circular, rectangular,
It can be rhombic or any other shape. External electrode 108
In addition, by forming such an opening 111, it is possible to realize a high aperture ratio of about 60% or more. External electrode
The formation of such openings 111 in 108 can be made by well-known means, including machining and chemical etching. Further, since the external electrode 108 holds both ends thereof by the electrode holding portions 105 and 106 made of a non-conductive material such as a synthetic resin,
It does not become unstable during operation.

As best shown in FIG. 4, the high frequency drive voltage is generated by a voltage generator 120 and applied between the inner electrode 101 and the outer electrode 108 of the dielectric barrier lamp 100. Since such a high-frequency voltage generator 120 is well known,
Here, the description is omitted.

The configuration and operation of the preferred embodiment of the dielectric barrier lamp according to the present invention have been described above in detail. However, it should be understood by those skilled in the art that the present invention should not be limited to only such specific embodiments, and that various modifications can be made in accordance with specific applications. For example, the internal electrode may be a conductive coating applied to the inner wall of the arc tube instead of the metal rod electrode of the specific embodiment.

[0020]

As can be understood from the above description, the dielectric barrier lamp according to the present invention has an aperture ratio of, for example, 60%.
Since the above values can be extremely high, it is possible to efficiently emit light such as ultraviolet rays emitted from the arc tube. Further, since the external electrode is securely held on the outer surface of the arc tube by the groove and the projection of the housing, a remarkable practical effect that light emission is extremely stabilized can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a preferred embodiment of a dielectric barrier lamp according to the present invention;

FIG. 2 is an end sectional view of the dielectric barrier lamp of FIG. 1;

FIG. 3 is a sectional view of an intermediate portion of the dielectric barrier lamp of FIG. 1;

4 is an external view showing an operation state of the dielectric barrier lamp of FIG. 1,

FIG. 5 is a longitudinal sectional view of a conventional dielectric barrier discharge lamp,

FIG. 6 is a sectional view of a conventional dielectric barrier discharge lamp device.

[Explanation of symbols]

 100 Dielectric barrier lamp 101 Internal electrode 102 Terminal 103 Arc tube 104 Discharge space 105 Electrode holding member 106 Electrode holding member 107 Housing 108 External electrode 110 External electrode fixing part 111 Opening 112 Spiral protrusion 113 Spiral groove

Claims (6)

[Claims] 1. A dielectric barrier lamp having an inner electrode and an outer electrode inside and outside a luminous tube having a double structure, respectively, wherein a rare gas is sealed in a discharge space of the luminous tube. Disposing a housing portion on the outer surface, forming a spiral groove and a spiral protrusion on the inner surface of the housing portion, and holding the external electrode disposed on the outer surface of the arc tube in the spiral groove. Characteristic dielectric barrier lamp. 2. The dielectric barrier lamp according to claim 1, wherein the external electrode is a thin metal strip-shaped electrode. 3. The light emitting portion of at least the external electrode,
3. The dielectric barrier lamp according to claim 2, wherein a number of small openings are formed. 4. The dielectric barrier lamp according to claim 1, wherein said internal electrode is a metal rod-shaped electrode inserted into a center hole of said arc tube. 5. The internal electrode is longer than the arc tube, and an electrode holding portion is arranged on at least one side of the arc tube to hold an end of the external electrode.
2. The dielectric barrier lamp according to claim 1. 6. An electrode fixing plate is provided at an end of said external electrode,
2. The dielectric barrier lamp according to claim 1, wherein a high-frequency drive voltage is applied to the electrode fixing plate.