JPH0992225A - Dielectric barrier discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric barrier discharge lamp having a high efficiency of emitting eximer beam of rare gas element and halogen element eximer and having a long service life. SOLUTION: This lamp has a pair of wall members 11, 12 facing to each other and being composed of dielectric respectively; a closed type discharge container 10 for forming a discharge space S between these wall members 11, 12; a pair of electrodes 21, 22 disposed on the outer surface of the respective members 11, 12; and discharge gas composed of rare gas and halogen gas and filled in the container 10. In the space S dielectric barrier discharge is generated, thereby eximer is generated by the rare gas element and the halogen element to emit eximer beam. In the thus provided dielectric barrier discharge lamp a light emitting element supply material 30 made of halogen compound being solid at the normal temp. is arranged in the vessel 10.

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 that emits excimer light by utilizing dielectric barrier discharge.

[0002]

2. Description of the Related Art As shown in FIG. 4, outer surfaces 83, 8 of a pair of wall members 81, 82 made of a dielectric material facing each other.
4, a pair of electrodes 85 and 86 are arranged, and these electrodes 8
When an AC voltage is applied between 5 and 86, the wall materials 81 and 82
It is known that a large number of needle-shaped discharge plasmas are generated during this period. Dielectric barrier discharge (also known as "Ozonizer discharge" or "Silent discharge". Such revised discharge "Handbook" published by The Institute of Electrical Engineers of Japan, Resale June 1991 7
Printing issuance, page 263). When this dielectric barrier discharge is generated in an appropriate discharge gas, excimer light peculiar to the composition of the discharge gas is emitted. The development of lamps that utilize discharge, that is, dielectric barrier discharge lamps, is in progress.

For example, in Japanese Unexamined Patent Publication No. 1-144560, a rare gas such as krypton-fluorine, krypton-chlorine, xenon-fluorine, xenon-chlorine or the like is contained in a discharge vessel at least a part of which is made of a dielectric material. A dielectric barrier discharge lamp filled with a discharge gas composed of a mixed gas of halogen gas is described.

When a mixed gas of a rare gas and a halogen gas is used as the discharge gas, the excimer light is emitted by the excimer of the rare gas element and the halogen element depending on the proportion of the halogen gas in the discharge gas. Since the efficiency changes, it is important to set the proportion of halogen gas so that a high luminous efficiency is obtained.

However, in a dielectric barrier discharge lamp filled with a halogen gas at a rate that can obtain high luminous efficiency, the intensity of excimer light emitted from the excimer of a rare gas element and a halogen element decreases early and is long. There is a problem that the service life cannot be obtained.

In order to elucidate the cause of this, a lamp in which the intensity of excimer light was lowered was examined, and it was found that the amount of halogen gas in the discharge vessel was significantly reduced. The cause of this is not clarified exactly, but because the halogen gas reacts with the material forming the discharge vessel during the lighting of the lamp, or the material forming the discharge vessel such as oxygen or hydrogen from the material forming the discharge vessel due to discharge or the like. It is considered that this is because the active substance is released, and the active substance reacts with the halogen gas to inhibit the contribution of halogen to the light emission. Therefore, if the halogen gas is overfilled, a somewhat long service life may be obtained, but with this, a dielectric barrier discharge lamp with high luminous efficiency cannot be obtained.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made based on the above circumstances, and its object is to provide:
An object of the present invention is to provide a dielectric barrier discharge lamp which has a high luminous efficiency of excimer light emitted from an excimer formed by a rare gas element and a halogen element and has a long service life.

[0008]

DISCLOSURE OF THE INVENTION A dielectric barrier discharge lamp of the present invention has one wall member and the other wall member, which are made of a dielectric material and which face each other, respectively, and the one wall member and the other wall member. A sealed discharge vessel forming a discharge space between the discharge vessel and one of the wall material and the other electrode on the outer surface of the other wall material in the discharge vessel, and the discharge A discharge gas composed of a rare gas and a halogen gas filled in the container, and by causing a dielectric barrier discharge in the discharge space of the discharge container, excimers due to the rare gas element and the halogen element are generated. A dielectric barrier discharge lamp that emits excimer light, wherein an element supplying substance for light emission composed of a halogen compound which is solid at room temperature is arranged in the discharge vessel. And butterflies.

In the above dielectric barrier discharge lamp, it is preferable that the halogen compound constituting the light emitting element supplying substance is a metal halogen compound, and further, the halogen compound constituting the light emitting element supplying substance is a lanthanoid. It is preferably a halide of one or more metals selected from group elements, yttrium, tin, lead, silver and barium.

In the above dielectric barrier discharge lamp, it is preferable that the vapor pressure of the halogen compound in the rated lighting state is 1 / 10,000 or less of the total pressure of the discharge gas.

Further, in the above-mentioned dielectric barrier discharge lamp, a light emitting element supply material accommodation chamber communicating with the discharge space is formed in the discharge vessel, and the light emission element supply material accommodation chamber is formed in the light emission element supply material accommodation chamber. A feed substance is preferably arranged.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The dielectric barrier discharge lamp of the present invention will be described in detail below. FIG. 1 is an explanatory sectional view showing the structure of an example of the dielectric barrier discharge lamp of the present invention. In this dielectric barrier discharge lamp,
It is composed of one cylindrical wall member 11 made of a dielectric material, and a dielectric material arranged in the one wall member 11 along its cylinder axis and having an outer diameter smaller than the inner diameter of the one wall member 11. Sealed discharge vessel 1 having another cylindrical wall member 12
0 is provided. In this discharge vessel 10, both end portions of one wall material 11 and the other wall material 12 are joined by sealing wall portions 13 and 14, and one wall material 11 and the other wall material 12 are connected to each other. A cylindrical discharge space S is formed.

As the dielectric material forming the one wall member 11 and the other wall member 12, for example, quartz glass can be used, and in particular, synthetic quartz having high transparency to vacuum ultraviolet rays having a wavelength of 160 to 200 nm. It is preferable to use glass. This synthetic quartz glass is VAD (Vapo
r-phased Axial Deposition
n) is a quartz glass manufactured by firing silica powder by a direct method or the like, and has a silica purity of 9
It is more than 9.99% by weight.

One wall member 11 of the discharge vessel 10 is provided with one mesh-like electrode 21 made of a conductive material such as a wire mesh in close contact with the outer peripheral surface 15 thereof, and the other wall member 11 of the discharge vessel 10 is The wall member 12 is provided with a film-shaped electrode 22 made of aluminum so as to cover the outer surface 16, and one electrode 21 and the other electrode 22 are connected to a high frequency power source 20, respectively.

The discharge vessel 10 is filled with a discharge gas composed of a mixed gas of a rare gas and a halogen gas, and is solid at room temperature by the same element as the halogen gas used as the discharge gas. The element supplying substance for light emission 30 composed of the halogen compound is disposed.

It is preferable to use a metal halogen compound as the halogen compound constituting the light emitting element supplying substance, and particularly, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium. It is preferable to use a halide of at least one metal selected from among thulium, ytterbium, lutetium (above, lanthanoid group elements), yttrium, tin, lead, silver and barium.

In the above, the vapor pressure of the halogen compound in the rated lighting state is 10000 of the total pressure of the discharge gas.
It is preferable that the ratio is not more than 1 /. This state can be set by selecting conditions such as the filling pressure of the discharge gas and the type of halogen compound. Here, the "vapor pressure of the halogen compound in the rated lighting state" means the vapor pressure of the halogen compound at the coldest point temperature of the outer surface of the discharge vessel when the lamp is lit at the rated temperature.

In the above dielectric barrier discharge lamp, when a high frequency voltage is applied between the one electrode 21 and the other electrode 22, a dielectric barrier discharge is generated in the discharge space S in the discharge vessel 10. Accordingly, an excimer (hereinafter, also referred to as “rare gas-halogen excimer”) is generated by the rare gas element and the halogen element, and excimer light emitted from the rare gas-halogen excimer is emitted from the one wall material 11 Is emitted to the outside from the mesh of the other electrode 21 via.

The halogen gas initially filled in the discharge vessel 10 gradually disappears, but the halogen gas is generated and replenished by gradually decomposing the light emitting element supply material 30. The decomposition of the light emitting element supply material 30 is performed by irradiating the light emitting element supply material 30 with excimer light emitted from the excimer of the rare gas element generated together with the rare gas-halogen excimer by the dielectric barrier discharge, and the discharge. It is thought to be caused by the heat generated by.

According to the above construction, the halogen gas is gradually replenished into the discharge space S from the light emitting element supply material 30 arranged in the discharge vessel 10 as the lamp lighting time elapses. The decrease in the amount of halogen gas in S is effectively compensated, and it becomes unnecessary to excessively fill the discharge vessel 10 with halogen gas, resulting in high luminous efficiency and service life. A long dielectric barrier discharge lamp is obtained.

Further, according to the constitution in which the halogen compound of the above-mentioned specific metal is used as the light emitting element supply substance 30, a residue produced by liberating halogen from the halogen compound, for example, a simple metal or a metal oxide. Since its vapor pressure is low, it is possible to suppress light emission due to the residue.

Further, by satisfying the condition that the vapor pressure of the halogen compound in the rated lighting state is 1 / 10,000 or less of the total pressure of the discharge gas, the light emission by the halogen compound molecule which is not an excimer becomes extremely small. Therefore, the target excimer light can be emitted with high efficiency.

FIG. 2 is an explanatory sectional view showing the structure of another example of the dielectric barrier discharge lamp of the present invention. In this dielectric barrier discharge lamp, one end side of the inner surface 17 of the other wall material 12 constituting the discharge vessel 10 has a circumference with a thickness smaller than the gap between the one wall material 11 and the other wall material 12. The ridge portion 18 extending in the direction is formed so as to protrude into the discharge space S, whereby the ridge portion 18 is formed.
A light emitting element supply substance accommodation chamber K communicating with the discharge space S is formed between the and the sealing wall portion 13. Then, the light emitting element supply material 3 is placed in the light emitting element supply material storage chamber K.
0 is arranged. Others are the same as those of the dielectric barrier discharge lamp shown in FIG.

According to such a dielectric barrier discharge lamp, the same effect as that of the dielectric barrier discharge lamp shown in FIG. 1 can be obtained, and in the light emitting element supply substance accommodation chamber K, which is the region other than the discharge space S. In addition, since the light emitting element supply material 30 is disposed, it is possible to prevent the halogen compound or the residue generated by releasing halogen from the halogen compound from being evaporated by sputtering.

The dielectric barrier discharge lamp of the present invention is not limited to the above-mentioned structure, and various modifications can be made. For example, the shape of the discharge vessel may be a box shape, a flat plate shape, or any other shape as long as it has one wall member and the other wall member that are made of a dielectric and face each other. In addition, a metal film made of aluminum is used as the other electrode, and a light extraction window member made of a translucent material is provided in place of the sealing wall portion 13 so that light is extracted from the end surface of the discharge container. Good.

Further, in the case of forming the light emitting element supply material accommodation chamber, as shown in FIG. 3, the discharge space S provided so as to extend outward from the sealing wall portion 13 of the discharge vessel 10 is formed. The remaining portion 19 of the exhaust pipe used for exhausting and filling the discharge gas forms a luminescence element supply material accommodation chamber K, and inside the luminescence element supply material accommodation chamber K, the luminescence element supply material 30. May be arranged.

Next, a method of manufacturing the above dielectric barrier discharge lamp will be described. First, the discharge vessel is filled with a noble gas, a halogen compound is placed, and then the halogen compound is decomposed by a decomposition treatment applied from the outside to release the halogen gas, whereby the inside of the discharge space is discharged. The dielectric barrier discharge lamp is manufactured by discharging the halogen gas required for the discharge. The decomposition treatment of the halogen compound can be performed by, for example, heat treatment, discharge treatment, or irradiation treatment with light or radiation.

Then, in the decomposition treatment of the halogen compound, by decomposing only a part of the halogen compound,
The remaining halogen compound is used as a light emitting element supplying material.

Further, when the discharge vessel in which the light emitting element supply material accommodation chamber is formed is used, a halogen compound is placed in the light emission element supply material accommodation chamber.

According to such a method, the halogen gas can be filled in the discharge vessel by disposing the halogen compound in the discharge vessel and decomposing it.
Dielectric barrier discharge lamps can be manufactured without directly using halogen gas, which is highly toxic and inconvenient to handle.

[0031]

EXAMPLES Examples of the dielectric barrier discharge lamp of the present invention will be described below. Example 1 A dielectric barrier discharge lamp A1 according to the present invention was produced according to the configuration shown in FIG. 1 and the following conditions. Discharge container (10): One wall material (11); synthetic quartz glass, total length about 150
mm, outer diameter 26.5 mm, inner diameter 23.5 mm (wall thickness 1.
5 mm), the other wall material (12); synthetic quartz glass, total length about 150
mm, outer diameter 14 mm, inner diameter 12 mm (wall thickness 1 mm), one electrode (21): made of stainless wire mesh, the other electrode (22): made of aluminum, discharge gas: xenon, light emitting element supply material (30): Dysprosium bromide 10
mg

Before starting the operation of the lamp, dysprosium bromide was heat-treated to decompose a part of the dysprosium bromide to generate about 0.6 mg of bromine, which was released into the discharge space.

When the above dielectric barrier discharge lamp A1 was lit by an AC wave having an applied voltage of 3.5 kV and a frequency of about 20 kHz by the power source (20), the power consumption was about 20 W and the wavelength was about 282 nm. Ultraviolet rays in the wavelength range of 270 to 320 nm having a maximum peak at (wavelength of excimer light emitted from excimer formed by xenon and bromine) were emitted.

The coldest spot temperature of the outer surface of the discharge vessel (10) during lighting is 100 ° C., and the vapor pressure of dysprosium bromide at this temperature (1 × 10 ⁻³⁰ atm).
Is 1 / 10,000 or less of the total pressure (30 kPa) of the discharge gas, and almost no light emission due to dysprosium bromide molecules was observed. In addition, the above dielectric barrier discharge lamp A1 is continuously turned on, and the total radiant flux maintenance rate is 70%.
When the time until it became% was examined, it was about 1000 hours.

<Comparative Example 1> Luminescent element supplying substance (30)
No bromine is added, and bromine is mixed with xenon as a discharge gas.
Dielectric barrier discharge lamp A except that 6 mg was enclosed.
A dielectric barrier discharge lamp B1 for comparison was produced under the same conditions as in No. 1, and the dielectric barrier discharge lamp B1 was lit under the same conditions as those of the dielectric barrier discharge lamp A1. The efficiency was equivalent to that of the dielectric barrier discharge lamp A1. Then, when the dielectric barrier discharge lamp B1 was continuously lit and the time until the maintenance rate of the total radiant flux reached 70% was examined, it was about 400.
It was time.

<Embodiment 2> According to the structure shown in FIG. 2, the ridge portion (18) is provided on the inner surface of the other wall material (12), and the discharge vessel (10) is provided with a luminous element supply substance accommodating chamber (K). ) Is formed, and 10 mg of yttrium iodide is provided as a luminescent element supply material (30) in the luminescent element supply material storage chamber (K).
, And by heating the yttrium iodide to decompose a part of it before starting the operation of the lamp,
A dielectric barrier discharge lamp A2 of the present invention was produced under the same conditions as for the dielectric barrier discharge lamp A1 except that about 1 mg of iodine was produced and discharged into the discharge space.

When the above-mentioned dielectric barrier discharge lamp A2 was lit under the same conditions as the dielectric barrier discharge lamp A1, the power consumption was about 20 W and the wavelength was about 253 nm (excimer emitted from xenon and iodine was emitted. 230 to 275 having a maximum peak in the wavelength of excimer light)
Ultraviolet radiation in the nm range was emitted. Further, the coldest spot temperature of the outer surface of the discharge vessel (10) during lighting is 100 ° C., and the vapor pressure (1 Pa or less) of yttrium iodide at this temperature is 10000 of the total pressure (30 kPa) of the discharge gas. It is less than one-third, and almost no light emission due to yttrium iodide molecules was observed. Further, when the above-mentioned dielectric barrier discharge lamp A2 was continuously turned on and the time until the maintenance rate of the total radiant flux reached 70% was examined, it was about 1200 hours.

<Comparative Example 2> Luminescent element supplying substance (30)
Iodine 1 with xenon as discharge gas
Dielectric barrier discharge lamp A2 except that mg is enclosed
A dielectric barrier discharge lamp B2 for comparison was produced under the same conditions as above, and this dielectric barrier discharge lamp B2 was lit under the same conditions as the dielectric barrier discharge lamp A1, and the initial luminous efficiency of excimer light was obtained. Was equivalent to the dielectric barrier discharge lamp A2. Then, when the dielectric barrier discharge lamp B2 was continuously lit and the time until the maintenance rate of the total radiant flux reached 70% was examined, it was about 500 hours.

Example 3 A dielectric barrier discharge lamp A according to the present invention having the structure shown in FIG. 3 and the following conditions.
3 was produced. Discharge container (10): One wall material (11); synthetic quartz glass, total length about 150
mm, outer diameter 26.5 mm, inner diameter 24.5 mm (wall thickness 1 m
m), the other wall material (12); synthetic quartz glass, total length about 150
mm, outer diameter 14 mm, inner diameter 12 mm (wall thickness 1 mm), one electrode: stainless steel wire mesh, the other electrode: aluminum, discharge gas: xenon Luminescent element supply substance (30): silver chloride 10 mg

Before starting the operation of the lamp, a low pressure mercury lamp was used to irradiate silver chloride with ultraviolet rays having a wavelength of 254 nm to decompose a part of the silver chloride, and thereby about 0.3
Chlorine (mg) was generated and released into the discharge space.

The above-mentioned dielectric barrier discharge lamp A3 was applied with a power source (20) at an applied voltage of about 8 kV and a frequency of about 3.
When it was turned on with an AC wave of 5 kHz, the power consumption was about 8
Ultraviolet rays having a wavelength of 280 to 350 nm, which is 0 W and has a maximum peak at a wavelength of about 308 nm (wavelength of excimer light emitted from excimer formed by xenon and chlorine), were emitted.

The coldest spot temperature of the outer surface of the discharge vessel (10) during lighting is 100 ° C., and the vapor pressure of silver chloride (1 Pa or less) at this temperature is the total pressure of the discharge gas (21 kPa). Of 1 / 10,000 or less, and almost no light emission due to silver chloride molecules was observed. Further, when the above dielectric barrier discharge lamp A3 was continuously lit and the time until the maintenance rate of the total radiant flux reached 70% was examined, it was about 900 hours.

<Comparative Example 3> Luminescent element supplying substance (30)
No chlorine was added, and chlorine was used as a discharge gas together with xenon.
Dielectric barrier discharge lamp A except that 3 mg was enclosed
A dielectric barrier discharge lamp B3 for comparison was produced under the same conditions as in No. 3, and the dielectric barrier discharge lamp B3 was lit under the same conditions as those of the dielectric barrier discharge lamp A3. The efficiency was equivalent to that of the dielectric barrier discharge lamp A3. Then, when the dielectric barrier discharge lamp B3 was continuously lit and the time until the maintenance rate of the total radiant flux reached 70% was examined, it was about 300.
It was time.

[0044]

According to the present invention, the halogen gas is gradually replenished to the discharge space from the light emitting element supplying substance arranged in the discharge vessel with the passage of the lighting time of the lamp. It is effectively compensated for the decrease in the amount of the gas, and it becomes unnecessary to overfill the discharge vessel with halogen gas. As a result, the dielectric barrier discharge has a high luminous efficiency and a long service life. You get a lamp.

Further, when a halogen compound of a specific metal is used as the light emitting element supplying substance, a residue produced by liberating halogen from the halogen compound, for example, a simple metal or a metal oxide, has a vapor pressure of Since it is low, light emission due to the residue can be suppressed.

Further, by satisfying the condition that the vapor pressure of the halogen compound in the rated lighting state is 1 / 10,000 or less of the total pressure of the discharge gas, the light emission by the halogen compound molecule which is not an excimer becomes extremely small. Therefore, the target excimer light can be emitted with high efficiency.

Further, a halogen compound is released from the halogen compound or the halogen compound by forming a light emitting element supply material accommodation chamber in the discharge vessel and disposing the light emission element supply material in the light emission element supply material accommodation chamber. It is possible to prevent the residue generated in this way from evaporating due to the grasshopper.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view showing a configuration of an example of a dielectric barrier discharge lamp of the present invention.

FIG. 2 is an explanatory sectional view showing the constitution of another example of the dielectric barrier discharge lamp of the present invention.

FIG. 3 is an explanatory cross-sectional view showing the constitution of still another example of the dielectric barrier discharge lamp of the present invention.

FIG. 4 is an explanatory diagram showing a principle for generating a dielectric barrier discharge.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Discharge vessel 11 One wall material 12 The other wall material 13,14 Sealing wall part 15 The outer surface of one wall material 16 The outer surface of the other wall material 17 The inner surface of the other wall material 18 The protrusion part 19 The remainder of the exhaust pipe 20 power source 21 one electrode 22 the other electrode 30 light emitting element supply material S discharge space K light emitting element supply material accommodation chamber 81,82 wall material 83,84 outer surface of wall material 85,86 electrode

Claims (5)

[Claims] 1. A hermetically sealed type having one wall member and the other wall member facing each other made of a dielectric material and forming a discharge space between the one wall member and the other wall member. A discharge vessel, one electrode and the other electrode disposed on the outer surface of each of the wall material and the other wall material of the discharge vessel, and a discharge composed of a rare gas and a halogen gas filled in the discharge vessel. A dielectric barrier discharge lamp having a working gas and generating a dielectric barrier discharge in a discharge space of the discharge container to generate an excimer by a rare gas element and a halogen element to emit excimer light. A dielectric barrier discharge lamp, wherein an element supply material for light emission made of a halogen compound which is solid at room temperature is arranged in the discharge vessel. 2. The dielectric barrier discharge lamp according to claim 1, wherein the halogen compound constituting the light emitting element supply material is a metal halogen compound. 3. The metal halide compound constituting the light emitting element supply material is a halide of one or more metals selected from the lanthanoid group elements, yttrium, tin, lead, silver and barium. The dielectric barrier discharge lamp according to claim 2. 4. The dielectric according to any one of claims 1 to 3, wherein the vapor pressure of the halogen compound in the rated lighting state is 1 / 10,000 or less of the total pressure of the discharge gas. Barrier discharge lamp. 5. A discharge vessel is provided with a luminescence element supply substance storage chamber communicating with the discharge space, and the luminescence element supply substance is arranged in the luminescence element supply substance storage chamber. The dielectric barrier discharge lamp according to any one of claims 1 to 4.