TW202011450A - Barrier discharge lamp capable of suppressing crack on illumination tube - Google Patents

Abstract

The present invention is provided to suppress decrease in luminous efficiency. According to one embodiment, a barrier discharge lamp includes a cylindrical illumination tube, an internal electrode, and a reflective film. The illumination tube is sealed with gas and passed by ultraviolet light. The internal electrode is disposed inside the illumination tube, and a spiral conductor extends in a tube axis direction of the illumination tube. The reflective film is provided on the inner surface of the illumination tube so that ultraviolet light is reflected toward the inside of the illumination tube. The barrier discharge lamp performs barrier discharge between an internal electrode disposed inside the illumination tube and an external electrode provided on the outer surface side of the illumination tube. In the internal electrode, when the wire diameter is set to be <pso> mm, and when the interval in the tube axis direction is set to be P mm, P/<pso> is above 10.0 and below 80.0.

Description

Barrier discharge lamp

The invention relates to an electric lamp, and in particular to a barrier discharge lamp.

Previously, there have been known barrier discharge lamps used for the purpose of cleaning or modifying substrates. The barrier discharge lamp uses a dielectric barrier discharge generated by connecting a spiral internal electrode arranged inside a light-emitting tube as a dielectric and an external electrode arranged outside the light-emitting tube to an AC power source. The internal gas corresponds to a specific wavelength of ultraviolet light. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2013-211164

[Problems to be solved by the invention]

In the barrier discharge lamp as described above, for example, the luminous efficiency may decrease due to the size of the internal electrode or the like.

The problem to be solved by the present invention is to provide a barrier discharge lamp that can suppress a decrease in luminous efficiency. [Means to solve the problem]

The barrier discharge lamp of the embodiment includes a cylindrical arc tube, internal electrodes, and a reflective film. The light-emitting tube is filled with gas and transmits ultraviolet light. The internal electrode is arranged inside the arc tube, and the spiral conductor extends in the tube axis direction of the arc tube. The reflective film is provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube. The barrier discharge lamp performs barrier discharge between an internal electrode provided inside the arc tube and an external electrode provided on the outer surface side of the arc tube. In the internal electrode, when the wire diameter is ψ mm and the interval in the tube axis direction is Pmm, P/ψ is 10.0 or more and 80.0 or less.

The barrier discharge lamp of another embodiment includes a cylindrical light-emitting tube, internal electrodes, and a reflective film. The cylindrical light-emitting tube is filled with gas and transmits ultraviolet light. The internal electrode is arranged inside the arc tube, and a spiral conductor extends in the tube axis direction of the arc tube. A reflective film is provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube. The barrier discharge lamp performs barrier discharge between the internal electrode provided inside the arc tube and the external electrode provided on the outer surface side of the arc tube. In the internal electrode, the wire diameter ψmm is 0.5 mm mm or more and 1.0 mm mm or less, and the interval Pmm in the tube axis direction is 10 mm or more and 50 mm mm or less.

In the barrier discharge lamp, the internal electrode has a coil portion, and when the coil outer diameter of the coil portion is Cmm, C/ψ is 25.0 or more and 90.0 or less. Furthermore, in the barrier discharge lamp, the distance between the outer surface of the coil portion included in the inner electrode and the inner surface of the arc tube is 3 mm or less. Furthermore, the length of the reflective film in the tube axis direction is equal to or greater than the length of the coil portion of the internal electrode in the tube axis direction.

The barrier discharge lamp of another embodiment includes a cylindrical light-emitting tube, an internal electrode, a reflective film, and an external electrode. The cylindrical light-emitting tube is filled with gas and transmits ultraviolet light. The internal electrode is arranged inside the arc tube, and a spiral conductor extends in the tube axis direction of the arc tube. A reflective film is provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube. The external electrode is provided on the outer surface side of the light emitting tube corresponding to the inner surface provided with the reflective film. In the internal electrode, when the wire diameter is ψ mm and the interval in the tube axis direction is Pmm, P/ψ is 10.0 or more and 80.0 or less.

The barrier discharge lamp of another embodiment includes a cylindrical light-emitting tube, an internal electrode, a reflective film, and an external electrode. The cylindrical light-emitting tube is filled with gas and transmits ultraviolet light. The internal electrode is arranged inside the arc tube, and a spiral conductor extends in the tube axis direction of the arc tube. A reflective film is provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube. The external electrode is provided on the outer surface side of the light emitting tube corresponding to the inner surface provided with the reflective film. In the internal electrode, the wire diameter ψ is 0.5 mm mm or more and 1.0 mm mm or less, and the interval P in the tube axis direction is 10 mm mm or more and 50 mm mm or less. [Effect of invention]

According to the present invention, cracking of the arc tube can be suppressed.

The barrier discharge lamp 1 of the embodiment described below includes a cylindrical light-emitting tube 2, an internal electrode 3, and a reflective film 4. The light-emitting tube 2 is filled with gas and transmits ultraviolet light. The internal electrode 3 is arranged inside the arc tube 2, and the spiral conductor extends in the tube axis direction of the arc tube 2. The reflective film 4 is provided on the inner surface 2 a of the light-emitting tube 2, and reflects ultraviolet light toward the inside of the light-emitting tube 2. The barrier discharge lamp 1 performs barrier discharge between the internal electrode 3 provided inside the arc tube 2 and the external electrode 7 provided on the outer surface 2b side of the arc tube 2. In the internal electrode 3, when the wire diameter is ψ [mm] and the interval in the tube axis direction is P [mm], P/ψ is 10.0 or more and 80.0 or less.

Furthermore, the barrier discharge lamp 1 of the embodiment described below includes a cylindrical arc tube 2, an internal electrode 3, and a reflective film 4. The light-emitting tube 2 is filled with gas and transmits ultraviolet light. The internal electrode 3 is arranged inside the arc tube 2, and the spiral conductor extends in the tube axis direction of the arc tube 2. The reflective film 4 is provided on the inner surface 2 a of the light-emitting tube 2, and reflects ultraviolet light toward the inside of the light-emitting tube 2. The barrier discharge lamp 1 performs barrier discharge between the internal electrode 3 provided inside the arc tube 2 and the external electrode 7 provided on the outer surface 2b side of the arc tube 2. In the internal electrode 3, the wire diameter ψ [mm] is 0.5 mm or more and 1.0 mm or less, and the interval P [mm] in the tube axis direction is 10 mm or more and 50 mm or less.

Furthermore, the internal electrode 3 of the embodiment described below has a coil portion 3a, and when the coil outer diameter of the coil portion 3a is C [mm], C/ψ is 25.0 or more and 90.0 or less.

Furthermore, in the embodiment described below, the distance between the outer surface 3a1 of the coil portion 3a and the inner surface 2a of the arc tube 2 is 3 mm or less.

Further, the length L4 of the reflective film 4 in the tube axis direction in the embodiment described below is equal to or greater than the length L3 of the coil portion 3a in the tube axis direction.

Moreover, the barrier discharge lamp 1 of the embodiment described below includes a cylindrical arc tube 2, an internal electrode 3, a reflective film 4, and an external electrode 7. The light-emitting tube 2 is filled with gas and transmits ultraviolet light. The internal electrode 3 is arranged inside the arc tube 2, and the spiral conductor extends in the tube axis direction of the arc tube 2. The reflective film 4 is provided on the inner surface 2 a of the light-emitting tube 2, and reflects ultraviolet light toward the inside of the light-emitting tube 2. The external electrode 7 is provided on the outer surface 2b side of the arc tube 2 corresponding to the inner surface 2a provided with the reflective film 4. In the internal electrode 3, when the wire diameter is ψ [mm] and the interval in the tube axis direction is P [mm], P/ψ is 10.0 or more and 80.0 or less.

Moreover, the barrier discharge lamp 1 of the embodiment described below includes a cylindrical arc tube 2, an internal electrode 3, a reflective film 4, and an external electrode 7. The light-emitting tube 2 is filled with gas and transmits ultraviolet light. The internal electrode 3 is arranged inside the arc tube 2, and the spiral conductor extends in the tube axis direction of the arc tube 2. The reflective film 4 is provided on the inner surface 2 a of the light-emitting tube 2, and reflects ultraviolet light toward the inside of the light-emitting tube 2. The external electrode 7 is provided on the outer surface 2b side of the arc tube 2 corresponding to the inner surface 2a provided with the reflective film 4. In the internal electrode 3, the wire diameter ψ [mm] is 0.5 mm or more and 1.0 mm or less, and the interval P [mm] in the tube axis direction is 10 mm or more and 50 mm or less.

Hereinafter, embodiments of the present invention will be described based on the drawings. In addition, the embodiments shown below do not limit the technology disclosed in the present invention.

[Embodiment] FIG. 1 is a plan view showing a barrier discharge lamp of an embodiment, and FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1. As shown in FIGS. 1 and 2, the barrier discharge lamp 1 of the embodiment includes a light-emitting tube 2, an internal electrode 3, a reflective film 4, a base 5, and a wire 6. Moreover, the barrier discharge lamp 1 performs barrier discharge between the external electrode 7 provided on the outer surface side of the barrier discharge lamp 1. In addition, in the present embodiment, the configuration in which the external electrode 7 is provided on the outer surface side of the barrier discharge lamp 1 may be combined with the barrier discharge lamp 1 and the external electrode 7, and more specifically The combination of the arc tube 2 and the external electrode 8 is called a "barrier discharge lamp".

In addition, for easy understanding of the description, FIGS. 1 and 2 illustrate a three-dimensional orthogonal coordinate system including the Z axis with the irradiation direction as the positive direction. Moreover, the illustration of the external electrode 7 is omitted in FIG. 1.

The arc tube 2 is a cylindrical member that transmits ultraviolet light. As a material of the arc tube 2, for example, synthetic quartz with a high vacuum ultraviolet transmittance of a wavelength of 200 nm or less can be exemplified. Furthermore, both ends of the arc tube 2 in the tube axis direction (Y-axis direction) are held by a sealing member having a rod structure, and are hermetically sealed. From the viewpoint of suppressing stress cracking caused by ultraviolet irradiation, for example, the outer diameter D [mm] of the arc tube 2 may be 30 mm or more. Furthermore, for example, the length of the arc tube 2 in the tube axis direction can be set to 750 mm.

In addition, gas is enclosed inside the arc tube 2. The gas is, for example, xenon gas of 80 kPa to 200 kPa. In addition, the gas may include, for example, one of krypton, xenon, argon, and neon, or a combination of multiple gases. In addition, the gas may contain, for example, halogen gas if necessary. The light-emitting tube 2 can emit ultraviolet light (eximer light) having a specific peak wavelength corresponding to the type of the enclosed gas.

The internal electrode 3 is arranged inside the arc tube 2. The coil portion 3 a which is a spiral conductor of the internal electrode 3 extends in the tube axis direction of the arc tube 2. The internal electrode 3 is formed of, for example, a material containing tungsten. Specifically, 50% or more of the total composition of the internal electrode 3 is tungsten. In particular, if doped tungsten obtained by adding potassium or the like to tungsten is used as the internal electrode 3, it can have higher dimensional stability.

Here, in the internal electrode 3, if the relationship between the wire diameter ψ [mm] and the interval P [mm] in the tube axis direction is expressed as P/ψ, P/ψ can be set to 10.0 or more and 80.0 or less, for example, 37.5 . If P/ψ is less than 10, so-called light shielding in which the internal electrode 3 itself becomes a shadow of ultraviolet light emitted from the arc tube 2 occurs, which is not preferable. On the other hand, if P/ψ exceeds 80.0, it is suggested that the interval P in the tube axis direction becomes wider. That is, at the portion where the internal electrode 3 and the external electrode 7 face each other, the electric field is concentrated, and the internal electrode 3 is red-hot. The red heat of the internal electrode 3 changes from a dielectric barrier discharge to a glow discharge or an arc discharge, and the excimer generated by the dielectric barrier discharge causes thermal dissociation, so the illuminance of ultraviolet light decreases. Therefore, it is not preferable to make P/ψ exceed 80.0. Therefore, it is desirable that P/ψ is 10.0 or more and 80.0 or less, and more preferably 15.0 to 40.0.

Furthermore, the wire diameter ψ [mm] of the internal electrode 3 can be, for example, 0.5 mm or more and 1.0 mm or less, and more specifically, for example, 0.8 mm. If the wire diameter ψ [mm] of the internal electrode 3 is set to less than 0.5 mm, the internal electrode 3 becomes red hot due to the power applied to the internal electrode 3, and the dielectric barrier discharge changes to glow discharge or arc discharge, and the dielectric barrier discharge The excimer produced causes thermal dissociation, so the illuminance of ultraviolet light decreases. Therefore, it is not preferable to make the wire diameter ψ [mm] of the internal electrode 3 less than 0.5 mm. On the other hand, if the wire diameter ψ of the internal electrode 3 exceeds 1.0 mm, the internal electrode 3 itself becomes a so-called light-shielding shadow of ultraviolet light emitted from the arc tube 2, which is not preferable. According to the above, for example, the wire diameter ψ [mm] of the internal electrode 3 can be set to 0.5 mm or more and 1.0 mm or less.

Furthermore, in the internal electrode 3, for example, the interval P [mm] in the tube axis direction can be set to, for example, 10 mm or more and 50 mm or less. If the interval P [mm] is less than 10 mm, the internal electrode 3 itself becomes a shadow of ultraviolet light emitted from the arc tube 2, which is not preferable. On the other hand, if the interval P [mm] is more than 50 mm, the electric field is concentrated at the portion where the internal electrode 3 and the external electrode 7 face, and the internal electrode 3 is red-hot. The red heat of the internal electrode 3 changes from a dielectric barrier discharge to a glow discharge or an arc discharge, and the excimer generated by the dielectric barrier discharge causes thermal dissociation, so the illuminance of ultraviolet light decreases. Therefore, it is not preferable to set the interval P [mm] to more than 40 mm. According to the above, by setting the interval P of the internal electrode 3 in the tube axis direction to 10 mm or more and 50 mm or less, ultraviolet light can be stably emitted.

Furthermore, if the relationship between the coil outer diameter C[mm] and the wire diameter ψ[mm] of the coil portion 3a of the internal electrode 3 is expressed as C/ψ, C/ψ can be set to 20.0 or more and 90.0 or less, for example, C/ ψ is 50.5. If C/ψ is less than 20.0, so-called light shielding in which the internal electrode 3 itself becomes a shadow of the ultraviolet light emitted from the arc tube 2 occurs, which is not preferable. On the other hand, if C/ψ exceeds 90.0, it becomes difficult to keep the interval P [mm] of the internal electrode 3 in the tube axis direction constant, and there is a non-uniform interval P of the internal electrode 3 in the tube axis direction possibility. When the interval P [mm] in the tube axis direction of the internal electrode 3 becomes uneven, the illuminance of the ultraviolet light in the tube axis direction of the arc tube 2 becomes uneven, which is not preferable. Therefore, C/ψ is preferably 20.0 or more and 90.0 or less, and more preferably 40.0 to 60.0.

Furthermore, the distance L between the outer surface 3a1 of the coil portion 3a of the internal electrode 3 and the inner surface 2a of the arc tube 2 is 3 mm or less. If the distance L between the outer surface 3a1 of the coil portion 3a and the inner surface 2a of the arc tube 2 exceeds 3 mm, the distance between the internal electrode 3, more specifically, the coil portion 3a of the internal electrode 3 and the external electrode 7 becomes large. If the distance between the coil portion 3a and the external electrode 7 becomes larger, the electric field that can be applied to the inside of the arc tube 2 decreases, the excitation energy required for generating excimers cannot be secured, and the luminous efficiency decreases due to the decrease in the illuminance of ultraviolet light. Not preferred. Therefore, it is desirable that the distance L [mm] between the outer surface 3a1 of the coil portion 3a and the inner surface 2a of the arc tube 2 is 3 mm or less, preferably 2.5 mm or less.

The reflective film 4 is provided on the inner surface 2 a of the light-emitting tube 2, and reflects ultraviolet light toward the inside of the light-emitting tube 2. As a material of the reflective film 4, for example, silicon dioxide can be exemplified. Furthermore, the reflective film 4 is not limited to silicon dioxide, and may include a material containing ultraviolet scattering particles such as alumina. From the viewpoint of maintaining good reflectance, the reflective film 4 is formed, for example, so that the thickness t [μm] becomes 100 μm or more and 300 μm or less. In addition, the reflective film 4 may be in contact with the coil portion 3a of the internal electrode 3, and may be away from it.

Furthermore, the reflective film 4 is arranged so that the circumferential angle θ of the arc tube 2 is 180° or more, for example, 200° or more and 300° or less. Further, the length L4 of the reflective film 4 in the tube axis direction is arranged so as to be equal to or greater than the length L3 of the coil portion 3 a of the internal electrode 3 in the tube axis direction. As a result, the ultraviolet light generated by the light-emitting tube 2 is efficiently irradiated to the object to be irradiated, and a decrease in luminous efficiency can be suppressed.

The external electrode 7 is provided on the outer surface 2b side of the light-emitting tube 2 corresponding to the inner surface 2a of the light-emitting tube 2 provided with the reflective film 4. The external electrode 7 also serves as a heat dissipation block for dissipating heat from the heat-generating barrier discharge lamp 1 and can be made of aluminum or stainless steel, for example. In addition, a flow path through which a liquid or gas refrigerant can flow is provided inside the external electrode 7 to further improve heat dissipation. The external electrode 7 and the light-emitting tube 2 may be in contact with each other or may be separated, but if the external electrode 7 is brought into contact with the light-emitting tube 2, heat dissipation can be improved. Furthermore, in the example shown in FIG. 2, the angle θ in the circumferential direction of the reflective film 4 is the same as the angle in the circumferential direction of the outer surface 2 b of the arc tube 2 covered by the external electrode 7, but it is not limited to This may be different from each other.

The lead 6 is electrically connected to the internal electrode 3. Furthermore, the lead wire 6 is pulled out from the base 5 that supports both ends of the arc tube 2 in the tube axis direction, and is electrically connected to the external electrode 7 via a lighting device (not shown) connected to an AC power source, which can A predetermined voltage is applied between the electrodes to emit light. The lighting device includes an inverter capable of outputting high voltage and high frequency, and is configured to be able to supply power from the AC power supply to the barrier discharge lamp 1. The lighting device can apply a sine wave with a frequency of 120 kHz, for example, and light the barrier discharge lamp 1 with a lamp power of about 1 kW.

[Evaluation Test] A lighting test was performed using a prototype of a barrier discharge lamp, and the luminous efficiency under the change of the interval P, the wire diameter ψ, and P/ψ in the tube axis direction of the internal electrode was evaluated. The results are shown in Table 1, respectively. In addition, the power [W] uses an oscilloscope TDS3012B (manufactured by Tektronix), the voltage probe uses P3000 (manufactured by Tektronix), and the current uses A6303 (manufactured by Tektronix) ). Ultraviolet (UV) illuminance [mW/cm2] is to connect VUV-S172 (manufactured by Ushio (USHIO) Motor Company) as the illuminance meter head to the main body of the illuminance meter UIT-250 (manufactured by Ushio (USHIO) Motor Company), so that The illuminance meter head contacts the barrier discharge lamp to measure the ultraviolet illuminance. In addition, in order to express the characteristics of the barrier discharge lamp, the value obtained by dividing the illuminance by electric power is taken as the luminous efficiency. In addition, regarding the state of the internal electrode, the luminous efficiency is 0.50 or more, and the internal electrode is not red heat as a criterion, and it is judged as ○: good, △: there is no problem in the internal electrode, but the luminous efficiency is 0.50 or less, ×: the internal electrode is red heat, There is a problem. As shown in Table 1, as long as P/ψ is 10.0 or more and 80.0 or less, the wire diameter ψ[mm] is 0.5 mm or more and 1.0 mm or less, and the interval P[mm] in the tube axis direction is 10 mm or more and 50 mm or less, Both can be judged as ○: good. From these results, the conditions for suppressing the decrease in luminous efficiency were confirmed. Table 1

As described above, the barrier discharge lamp 1 of the embodiment includes the cylindrical arc tube 2, the internal electrode 3, and the reflective film 4. The light-emitting tube 2 is filled with gas and transmits ultraviolet light. The internal electrode 3 is arranged inside the arc tube 2, and the spiral conductor extends in the tube axis direction of the arc tube 2. The reflective film 4 is provided on the inner surface 2 a of the light-emitting tube 2, and reflects ultraviolet light toward the inside of the light-emitting tube 2. The barrier discharge lamp 1 performs barrier discharge between the internal electrode 3 provided inside the arc tube 2 and the external electrode 7 provided near the arc tube 2, that is, on the outer surface 2 b side. In the internal electrode 3, when the wire diameter is ψ [mm] and the interval in the tube axis direction is P [mm], P/ψ is 10.0 or more and 80.0 mm or less. As a result, a decrease in the luminous efficiency of the barrier discharge lamp 1 can be suppressed.

Moreover, the barrier discharge lamp 1 of the embodiment includes a cylindrical light-emitting tube 2, internal electrodes 3, and a reflective film 4. The light-emitting tube 2 is filled with gas and transmits ultraviolet light. The internal electrode 3 is arranged inside the arc tube 2, and the spiral conductor extends in the tube axis direction of the arc tube 2. The reflective film 4 is provided on the inner surface 2 a of the light-emitting tube 2, and reflects ultraviolet light toward the inside of the light-emitting tube 2. The barrier discharge lamp 1 performs barrier discharge between the internal electrode 3 provided inside the arc tube 2 and the external electrode 7 provided near the arc tube 2, that is, on the outer surface 2 b side. In the internal electrode 3, the wire diameter ψ [mm] is 0.5 mm or more and 1.0 mm or less, and the interval P [mm] in the tube axis direction is 10 mm or more and 50 mm or less. As a result, a decrease in the luminous efficiency of the barrier discharge lamp 1 can be suppressed.

Furthermore, in the barrier discharge lamp 1 of the embodiment, the internal electrode 3 has the coil portion 3a, and when the coil outer diameter of the coil portion 3a is C [mm], C/ψ is 25.0 or more and 90.0 or less. As a result, a decrease in the luminous efficiency of the barrier discharge lamp 1 can be suppressed.

Furthermore, in the embodiment, the distance L [mm] between the outer surface 3a1 of the coil portion 3a and the inner surface 2a of the arc tube 2 is 3 mm or less. As a result, a decrease in the luminous efficiency of the barrier discharge lamp 1 can be suppressed.

Furthermore, the length L4 in the tube axis direction of the reflective film 4 of the embodiment is equal to or greater than the length L3 in the tube axis direction of the coil portion 3 a of the internal electrode 3. As a result, a decrease in the luminous efficiency of the barrier discharge lamp 1 can be suppressed.

Although the embodiments of the present invention have been described, the embodiments are presented as examples and are not intended to limit the scope of the invention. The embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. As in the scope or gist of the invention, the embodiment or its modifications are included in the invention described in the claims and their equivalent scope.

1: Block discharge lamp 2: LED 2a: the inner surface of the luminous tube 2b: the outer surface of the luminous tube 3: internal electrode 3a: Coil part 3a1: outer surface of the coil part 4: reflective film 5: lamp holder 6: Wire 7: external electrode C: Coil outer diameter of the coil part D: the outer diameter of the luminous tube L: distance between the outer surface of the coil part and the inner surface of the arc tube L3: Length of the coil part in the direction of the tube axis L4: Length of the reflective film in the direction of the tube axis P: interval of the internal electrode in the tube axis direction t: thickness X, Y, Z: direction ψ: wire diameter of internal electrode θ: angle

FIG. 1 is a plan view showing a barrier discharge lamp of an embodiment. FIG. 2 is an A-A cross-sectional view of FIG. 1.

1: Block discharge lamp

2: LED

3: internal electrode

3a: Coil part

4: reflective film

5: lamp holder

6: Wire

L3: Length of the coil part in the direction of the tube axis

L4: Length of the reflective film in the direction of the tube axis

P: interval of the internal electrode in the tube axis direction

X, Y, Z: direction

Claims (7)

A barrier discharge lamp, including: The cylindrical light-emitting tube is filled with gas and transmits ultraviolet light; An internal electrode disposed inside the light-emitting tube, and a spiral conductor extending in the tube axis direction of the light-emitting tube; and A reflective film is provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube, and A barrier discharge is performed between the internal electrode provided inside the arc tube and the external electrode provided on the outer surface side of the arc tube, In the internal electrode, when the wire diameter is ψ mm and the interval in the tube axis direction is Pmm, P/ψ is 10.0 or more and 80.0 or less. A barrier discharge lamp, including: The cylindrical light-emitting tube is filled with gas and transmits ultraviolet light; An internal electrode disposed inside the light-emitting tube, and a spiral conductor extending in the tube axis direction of the light-emitting tube; and A reflective film is provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube, and A barrier discharge is performed between the internal electrode provided inside the arc tube and the external electrode provided on the outer surface side of the arc tube, In the internal electrode, the wire diameter ψmm is 0.5 mm or more and 1.0 mm or less, and the interval Pmm in the tube axis direction is 10 mm or more and 50 mm or less. The barrier discharge lamp according to claim 1 or claim 2, wherein the internal electrode has a coil portion, and when the coil outer diameter of the coil portion is Cmm, C/ψ is 25.0 or more and 90.0 or less . The barrier discharge lamp according to claim 1 or claim 2, wherein the distance between the outer surface of the coil portion included in the inner electrode and the inner surface of the arc tube is 3 mm or less. The barrier discharge lamp according to item 1 or item 2 of the patent application range, wherein the length of the reflective film in the tube axis direction is the tube axis direction of the coil portion included in the internal electrode Above the length. A barrier discharge lamp, including: The cylindrical light-emitting tube is filled with gas and transmits ultraviolet light; The internal electrode is arranged inside the light-emitting tube, and a spiral conductor extends in the tube axis direction of the light-emitting tube; A reflective film provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube; and An external electrode provided on the outer surface side of the light emitting tube corresponding to the inner surface provided with the reflective film, In the internal electrode, when the wire diameter is ψ mm and the interval in the tube axis direction is Pmm, P/ψ is 10.0 or more and 80.0 or less. A barrier discharge lamp, including: The cylindrical light-emitting tube is filled with gas and transmits ultraviolet light; The internal electrode is arranged inside the light-emitting tube, and a spiral conductor extends in the tube axis direction of the light-emitting tube; A reflective film provided on the inner surface of the light-emitting tube to reflect the ultraviolet light toward the inside of the light-emitting tube; and An external electrode provided on the outer surface side of the light emitting tube corresponding to the inner surface provided with the reflective film, In the internal electrode, the wire diameter ψ is 0.5 mm or more and 1.0 mm or less, and the interval P in the tube axis direction is 10 mm or more and 50 mm or less.

Images