Barrier discharge lamps and barrier discharge lamp modules

Abstract

The objective is to provide a barrier discharge lamp and a barrier discharge lamp module that can appropriately detect the illuminance of ultraviolet light irradiated onto an object. [Solution] The barrier discharge lamp according to the embodiment comprises: a discharge tube having a cylindrical shape and gas sealed in its internal space; a first electrode provided on the outer wall of the discharge tube; a second electrode provided on the outer wall of the discharge tube or in the internal space of the discharge tube and facing the first electrode; a first reflective film provided on the inner wall of the discharge tube and having a hole penetrating in the thickness direction; and a second reflective film provided on the inner wall of the discharge tube and facing the hole of the first reflective film.

Description

Technical Field

[0001] Embodiments of the present invention relate to a barrier discharge lamp and a barrier discharge lamp module.

Background Art

[0002] There is a barrier discharge lamp that irradiates ultraviolet rays with a wavelength of 200 nm or less. The barrier discharge lamp is used, for example, for surface treatment such as removal of organic substances attached to the surface of an object (photo cleaning treatment), surface modification, and formation of an oxide film.

[0003] The barrier discharge lamp includes a light-emitting tube having a tubular shape, a pair of electrodes facing each other, and a reflective film provided on the inner wall of the light-emitting tube. In such a barrier discharge lamp, when power is applied to the pair of electrodes, dielectric barrier discharge occurs inside the light-emitting tube, and ultraviolet rays having a specific wavelength are generated according to the type of gas enclosed inside the light-emitting tube. The generated ultraviolet rays are directly irradiated to the outside through the light-emitting tube, or are irradiated to the outside through the light-emitting tube after being reflected by the reflective film provided on the inner wall of the light-emitting tube.

[0004] Here, the light-emitting tube is formed of, for example, synthetic quartz glass. Synthetic quartz glass has high resistance to ultraviolet rays, but when the time for ultraviolet rays to enter is long, defects occur in the chemical structure, and the transmittance of ultraviolet rays may decrease over time. When the transmittance of ultraviolet rays decreases over time, the illuminance of the ultraviolet rays irradiated to the object to be processed may decrease over time, and there is a risk that the processing of the object becomes insufficient or unevenness occurs in the processing.

[0005] Therefore, a technique has been proposed in which holes are provided in the reflective film provided on the inner wall of the light-emitting tube, and the illuminance of the ultraviolet rays emitted through the holes in the reflective film is detected. By controlling the power applied to the pair of electrodes based on the illuminance of the ultraviolet rays emitted through the holes in the reflective film, it is possible to suppress the decrease in the illuminance of the ultraviolet rays irradiated to the object to be processed over time.

[0006] Here, the ultraviolet light irradiated onto the object being processed includes ultraviolet light emitted directly through the discharge tube and ultraviolet light emitted through the discharge tube after being reflected by the reflective film. In contrast, if holes are simply made in the reflective film, the ultraviolet light emitted through the holes in the reflective film (the ultraviolet light to be detected) includes ultraviolet light emitted directly through the discharge tube and the holes in the reflective film, but it hardly includes ultraviolet light emitted through the discharge tube after being reflected by the reflective film.

[0007] Therefore, the difference between the illuminance of ultraviolet light irradiated onto the object being processed and the illuminance of ultraviolet light to be detected may become large, potentially making it impossible to properly detect the illuminance of ultraviolet light irradiated onto the object.

[0008] Therefore, there was a need for the development of a technology that could accurately detect the intensity of ultraviolet light irradiated onto an object. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2010-225343 [Overview of the project] [Problems that the invention aims to solve]

[0010] The problem that this invention aims to solve is to provide a barrier discharge lamp and a barrier discharge lamp module that can appropriately detect the illuminance of ultraviolet light irradiated onto an object. [Means for solving the problem]

[0011] The barrier discharge lamp according to the embodiment comprises: a discharge tube having a cylindrical shape and a gas sealed in its internal space; a first electrode provided on the outer wall of the discharge tube; a second electrode provided on the outer wall of the discharge tube or in the internal space of the discharge tube and facing the first electrode; a first reflective film provided on the inner wall of the discharge tube and having a hole penetrating in the thickness direction; and a second reflective film provided on the inner wall of the discharge tube and facing the hole of the first reflective film. [Effects of the Invention]

[0012] According to embodiments of the present invention, it is possible to provide a barrier discharge lamp and a barrier discharge lamp module that can appropriately detect the illuminance of ultraviolet light irradiated onto an object. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic diagram illustrating a barrier discharge lamp module according to this embodiment. [Figure 2] This is a schematic diagram of the barrier discharge lamp shown in Figure 1, viewed from the Z direction. [Figure 3] Figure 2 is a schematic cross-sectional view of the barrier discharge lamp in the direction of line AA. [Figure 4] Figure 2 is a schematic cross-sectional view of the barrier discharge lamp in the direction of the BB line. [Figure 5] This is a schematic diagram illustrating a barrier discharge lamp according to another embodiment. [Figure 6] Figure 5 is a schematic cross-sectional view of the barrier discharge lamp in the CC line direction. [Modes for carrying out the invention]

[0014] The embodiments will be illustrated below with reference to the drawings. In each drawing, similar components are denoted by the same reference numerals, and detailed descriptions will be omitted as appropriate.

[0015] In each figure, the arrows X, Y, and Z represent three mutually orthogonal directions. For example, the X direction can be the direction in which the barrier discharge lamp extends (the length direction). For example, the Y direction can be the width direction of the barrier discharge lamp. For example, the Z direction can be the direction in which the electrode 13 (corresponding to an example of the first electrode) and the electrode 14 (corresponding to an example of the second electrode) face each other.

[0016] FIG. 1 is a schematic diagram for exemplifying a barrier discharge lamp module 100 according to the present embodiment. As shown in FIG. 1, the barrier discharge lamp module 100 is provided with, for example, a barrier discharge lamp 1, a detection unit 2, and a controller 3.

[0017] FIG. 2 is a schematic diagram when the barrier discharge lamp 1 in FIG. 1 is viewed from the Z direction. FIG. 3 is a schematic cross-sectional view in the direction of the A-A line of the barrier discharge lamp 1 in FIG. 2. FIG. 4 is a schematic cross-sectional view in the direction of the B-B line of the barrier discharge lamp 1 in FIG. 2. As shown in FIGS. 2 to 4, the barrier discharge lamp 1 includes, for example, a light-emitting tube 11, a reflection film 12 (corresponding to an example of the first reflection film), an electrode 13, and an electrode 14.

[0018] The light-emitting tube 11 has a cylindrical shape and extends in the X direction. For example, both ends of the light-emitting tube 11 are closed. The contour of the light-emitting tube 11 when viewed from the X direction can be a flat shape. The flat shape is, for example, a shape in which the dimension of the light-emitting tube 11 in the Y direction is shorter than the dimension of the light-emitting tube 11 in the Z direction. If the contour of the light-emitting tube 11 is a flat shape, the distance between the electrode 13 and the electrode 14 becomes shorter, so it becomes easy to generate a dielectric barrier discharge between the electrode 13 and the electrode 14.

[0019] When viewed from the X direction, the outline of the discharge tube 11 can be, for example, substantially rectangular or substantially elliptical. The outlines of the discharge tubes 11 illustrated in FIGS. 3 and 4 are substantially rectangular. If the outline of the discharge tube 11 is substantially rectangular, it becomes easy to provide the electrodes 13 and 14 on the outer wall of the discharge tube 11.

[0020] The lengths of the discharge tube 11 in the X direction and the Y direction can be appropriately set according to the dimensions of the irradiation region of the required ultraviolet rays 200. The length (thickness) of the discharge tube 11 in the Z direction is, for example, about 10 mm to 15 mm. The wall thickness of the discharge tube 11 is, for example, about 2 mm.

[0021] A gas is enclosed in the internal space of the discharge tube 11. In the dielectric barrier discharge lamp 1, dielectric barrier discharge is performed between the electrodes 13 and 14 to give high-energy electrons to the enclosed gas to generate excimer-excited molecules. When the excimer-excited molecules return to their original state, light having a specific peak wavelength is generated according to the type of the gas. Therefore, the gas enclosed in the internal space of the discharge tube 11 can be appropriately changed according to the use of the dielectric barrier discharge lamp 1. The gas enclosed in the internal space of the discharge tube 11 can be, for example, a noble gas such as krypton, xenon, argon, neon, or a mixed gas in which a plurality of types of noble gases are mixed. Further, the gas can further contain a halogen gas or the like as necessary.

[0022] The pressure of the gas (enclosure pressure) in the internal space of the discharge tube 11 at 25°C is, for example, about 1.3 kPa to 100 kPa. The enclosure pressure can be determined by the standard state of the gas (SATP (Standard Ambient Temperature and Pressure): temperature 25°C, 1 bar).

[0023] For example, when photocleaning the surface of a glass plate for a flat panel display or when decomposing organic matter, it is preferable to use xenon as the sealed gas. In this case, the sealing pressure of the xenon can be, for example, about 93 kPa. By using xenon as the sealed gas, ultraviolet 200 with a peak wavelength of 172 nm can be generated, thereby enhancing the photocleaning effect and the decomposition effect of organic matter.

[0024] Ultraviolet light 200 generated in the internal space of the discharge tube 11 is irradiated to the outside through the discharge tube 11. Therefore, the discharge tube 11 is made of a material with high transmittance of ultraviolet light 200. Examples of materials with high transmittance of ultraviolet light 200 include synthetic quartz glass.

[0025] The reflective film 12 is film-like and extends in the X direction. The reflective film 12 is provided on the inner wall of the discharge tube 11 and faces the electrode 13 across the discharge tube 11. As shown in Figure 4, the reflective film 12 can be provided, for example, on the inner wall of the discharge tube 11 facing the electrode 13, and on a pair of inner walls that intersect the inner wall facing the electrode 13. The reflective film 12 is not provided on the inner wall of the discharge tube 11 facing the electrode 14.

[0026] Therefore, if a reflective film 12 is provided, ultraviolet rays 200 generated in the internal space of the discharge tube 11 that do not go toward the inner wall of the discharge tube 11 facing the electrode 14 can be reflected toward the inner wall of the discharge tube 11 facing the electrode 14. In other words, the reflective film 12 reflects ultraviolet rays 200 that do not go toward the direction of irradiation toward the direction of irradiation.

[0027] The thickness of the reflective film 12 can be, for example, about 100 μm to 300 μm. This makes it easy to maintain good reflectivity against ultraviolet 200. The reflective film 12 can be formed using a material containing ultraviolet scattering particles, such as SiO2 (silicon dioxide) or aluminum oxide.

[0028] If the reflective film 12 is provided, the extraction efficiency of ultraviolet 200 can be improved. In addition, if the reflective film 12 is provided, the area of ​​the discharge tube 11 that is directly affected by ultraviolet 200 can be reduced, thereby suppressing chemical structural changes of the discharge tube 11 caused by the incidence of ultraviolet 200.

[0029] The electrode 13 is provided on the outer wall of the discharge tube 11. As shown in Figure 4, the electrode 13 is provided on the side of the discharge tube 11 opposite to the side from which ultraviolet light 200 is emitted. The electrode 13 faces the reflective film 12, with the discharge tube 11 in between. In this case, if a gap occurs between the electrode 13 and the outer wall of the discharge tube 11, the amount of power supplied to the internal space of the discharge tube 11 may vary. Therefore, it is preferable that the electrode 13 be in close contact with the outer wall of the discharge tube 11.

[0030] The electrode 14 is provided on the outer wall of the discharge tube 11. As shown in Figure 4, the electrode 14 is provided on the side of the discharge tube 11 from which ultraviolet light 200 is emitted. The portion of the inner wall of the discharge tube 11 facing the electrode 14 does not have a reflective film 12. In this case, if a gap occurs between the electrode 14 and the outer wall of the discharge tube 11, the amount of power supplied to the internal space of the discharge tube 11 may vary. Therefore, it is preferable to make the electrode 14 in close contact with the outer wall of the discharge tube 11.

[0031] As shown in Figure 1, the electrode 14 is located on the side of the discharge tube 11 from which the ultraviolet light 200 is emitted. Therefore, the electrode 14 is permeable to ultraviolet light 200. In this case, if the light shielding rate of the electrode 14 is increased, the amount of power supplied to the internal space of the discharge tube 11 increases, making dielectric barrier discharge more likely to occur. However, if the light shielding rate of the electrode 14 is made too high, the illuminance of ultraviolet light 200 irradiated onto the object to be processed becomes too low. Therefore, it is preferable that the light shielding rate of the electrode 14 be between 10% and 40%.

[0032] Furthermore, as shown in Figure 1, the detection unit 2 is located on the side of the discharge tube 11 where the electrode 13 is provided. Therefore, the electrode 13 is capable of transmitting ultraviolet light 200 generated in the internal space of the discharge tube 11 so that the ultraviolet light 200 generated in the internal space of the discharge tube 11 is incident on the light receiving part of the detection unit 2. As will be described later, it is preferable that the illuminance of the ultraviolet light incident on the detection unit 2 be approximately the same as the illuminance of the ultraviolet light 200 irradiated to the outside via the electrode 14. Therefore, it is preferable that the light shielding rate of the electrode 13 be approximately the same as the light shielding rate of the electrode 14. For example, the electrode 13 can be the same as the electrode 14.

[0033] As shown in Figure 2, electrodes 13 and 14 have a grid-like structure, for example. Electrodes 13 and 14 can be formed by applying a material in a grid pattern to the outer wall of the discharge tube 11 using a printing method such as inkjet printing or screen printing, and then curing it. Alternatively, electrodes 13 and 14 can be formed directly on the outer wall of the discharge tube 11 using a flexographic printing method, for example.

[0034] Electrodes 13 and 14 can be formed from, for example, a conductive material. In this case, when ultraviolet light 200 is irradiated onto air in the atmosphere in which the barrier discharge lamp 1 is provided, ozone may be generated. Therefore, it is preferable that electrodes 13 and 14 be formed from a conductive material that does not react easily with ozone. Electrodes 13 and 14 can be formed from, for example, gold or a gold alloy.

[0035] Furthermore, electrodes 13 and 14 can also be, for example, mesh-like. Electrodes 13 and 14 can, for example, have a knitted braided structure formed from Monel wire with a diameter of about 0.1 mm.

[0036] In this case, as mentioned above, it is preferable that electrodes 13 and 14 be in close contact with the outer wall of the discharge tube 11. Therefore, it is preferable that electrodes 13 and 14 be formed directly on the outer wall of the discharge tube 11 using an inkjet method or a flexographic printing method.

[0037] Furthermore, as shown in Figure 2, a film-like terminal 13a can be provided at the end of the electrode 13 in the X direction. The terminal 13a can be provided at at least one end of the electrode 13. In the electrode 13 illustrated in Figure 2, terminals 13a are provided at each of the ends on both sides of the electrode 13. The material of the terminal 13a can be the same as the material of the electrode 13.

[0038] A film-like terminal 14a can be provided at the end of the electrode 14 in the X direction. The terminal 14a can be provided at at least one end of the electrode 14. In the electrode 14 illustrated in Figure 2, terminals 14a are provided at each of the ends on both sides of the electrode 14. The material of the terminal 14a can be the same as the material of the electrode 14.

[0039] Furthermore, a cover can be provided to cover terminals 13a and 14a. The cover can be made from an insulating material such as resin or ceramics.

[0040] As mentioned above, the discharge tube 11 is made of, for example, synthetic quartz glass. Synthetic quartz glass has high resistance to ultraviolet 200, but if the incident time of ultraviolet 200 is long, defects may occur in the chemical structure of the synthetic quartz glass, and the transmittance of ultraviolet 200 may decrease over time. If the transmittance of ultraviolet 200 decreases over time, the irradiance of ultraviolet 200 onto the object to be treated will decrease over time, which may result in insufficient treatment of the object or uneven treatment.

[0041] Therefore, the barrier discharge lamp module 100 is provided with a detection unit 2. The detection unit 2 detects the illuminance of ultraviolet 200 generated in the internal space of the discharge tube 11 and emitted to the outside of the discharge tube 11. As will be described later, the detection unit 2 detects the ultraviolet 200 emitted through the holes 12a and 42a of the reflective films 12 and 42. The detection unit 2 is not particularly limited as long as it is capable of converting the illuminance of the incident ultraviolet 200 into an electrical signal. The detection unit 2 can be, for example, an ultraviolet illuminometer.

[0042] In this case, the detection unit 2 can also be installed on the side of the barrier discharge lamp 1 from which the ultraviolet light 200 is emitted. However, when irradiating an object to be processed with ultraviolet light, the object to be processed is placed on the side of the barrier discharge lamp 1 from which the ultraviolet light 200 is emitted. Therefore, if the detection unit 2 is installed on the side of the barrier discharge lamp 1 from which the ultraviolet light 200 is emitted, the distance between the barrier discharge lamp 1 and the object to be processed will increase. Since the inverse square law applies between the illuminance of ultraviolet light 200 and the distance, installing the detection unit 2 on the side of the barrier discharge lamp 1 from which the ultraviolet light 200 is emitted may significantly reduce the illuminance of the ultraviolet light irradiated onto the object to be processed.

[0043] Therefore, as shown in Figure 1, the detection unit 2 is located on the side of the barrier discharge lamp 1 opposite to the side from which the ultraviolet light 200 is emitted. In this way, even with the detection unit 2 installed, the distance between the barrier discharge lamp 1 and the object to be processed can be set to an appropriate range.

[0044] In this case, if the reflective film 12 is positioned opposite the detection unit 2, the ultraviolet light 200 incident on the detection unit 2 will be blocked by the reflective film 12. Therefore, as shown in Figure 2, a hole 12a penetrating the thickness direction is provided near one end of the reflective film 12 in the X direction. The hole 12a of the reflective film 12 is opposite the vicinity of one end of the electrode 13. The light receiving part of the detection unit 2 is opposite the hole 12a of the reflective film 12.

[0045] Furthermore, as mentioned above, the electrode 13 is capable of transmitting ultraviolet light 200. Therefore, the ultraviolet light 200 generated in the internal space of the discharge tube 11 enters the light-receiving section of the detection unit 2 through the holes 12a in the reflective film 12, the discharge tube 11, and the electrode 13.

[0046] As shown in Figure 1, the controller 3 is electrically connected to the terminal 13a of electrode 13, the terminal 14a of electrode 14, and the detection unit 2. The controller 3 includes an arithmetic unit such as a CPU (Central Processing Unit) and a storage unit such as memory. The controller 3 is, for example, a computer. The controller 3 may also further include a lighting circuit and power supply for lighting the barrier discharge lamp 1.

[0047] For example, the controller 3 controls the power applied to electrodes 13 and 14 so that the illuminance of ultraviolet 200 detected by the detection unit 2 is within a predetermined range. In this way, even if the transmittance of ultraviolet 200 in the discharge tube 11 decreases over time, the illuminance of ultraviolet 200 irradiated onto the object being processed can be kept within a predetermined range. As a result, the quality of the processed object can be kept within a predetermined range, and the usable period of the barrier discharge lamp 1 can be extended.

[0048] Here, the ultraviolet light 200 irradiated onto the object to be processed includes ultraviolet light 200 that is emitted directly through the discharge tube 11 and electrode 14, and ultraviolet light 200 that is reflected by the reflective film 12 and then emitted through the discharge tube 11 and electrode 14.

[0049] In contrast, if holes 12a are simply provided in the reflective film 12, the ultraviolet light 200 incident on the light receiving part of the detection unit 2 includes ultraviolet light 200 that is directly emitted through the discharge tube 11, the holes 12a in the reflective film 12, and the electrode 13, but hardly any ultraviolet light 200 that is reflected by the reflective film 12 is included.

[0050] Therefore, a difference may occur between the illuminance of ultraviolet 200 irradiated onto the object being processed and the illuminance of ultraviolet 200 detected by the detection unit 2, which may prevent the controller 3 from properly controlling the illuminance of ultraviolet 200.

[0051] Therefore, as shown in Figures 2 and 3, a reflective film 12b (corresponding to an example of a second reflective film) is also provided on the inner wall of the discharge tube 11 facing the electrode 14. As shown in Figure 3, the reflective film 12b is connected to the reflective film 12. In the X direction, the length of the reflective film 12b is shorter than the length of the reflective film 12. As shown in Figure 2, when viewed from the Z direction, the reflective film 12b is provided near the end of the reflective film 12 on the side where the hole 12a is provided. The reflective film 12b is provided on the inner wall of the discharge tube 11 and faces the hole 12a of the reflective film 12. When viewed from the Z direction, the hole 12a of the reflective film 12 is located inside the reflective film 12b. The thickness and material of the reflective film 12b can be the same as the thickness and material of the reflective film 12.

[0052] As shown in Figures 2 and 4, when viewed from the Z direction, in the region of the barrier discharge lamp 1 that irradiates ultraviolet light 200 toward the object to be processed, the electrode 13, discharge tube 11, reflective film 12, and electrode 14 overlap.

[0053] When viewed from the Z direction, in the region of the barrier discharge lamp 1 where the illuminance of ultraviolet 200 is detected (the region where the detection unit 2 is provided), the electrode 13, discharge tube 11, reflective film 12b, and electrode 14 overlap.

[0054] Therefore, the irradiation conditions of ultraviolet 200 irradiated onto the object to be processed and the irradiation conditions of ultraviolet 200 detected by the detection unit 2 are approximately the same, so the difference between the illuminance of ultraviolet 200 irradiated onto the object to be processed and the illuminance of ultraviolet 200 detected by the detection unit 2 can be reduced. In other words, appropriate detection of the illuminance of ultraviolet rays irradiated onto the object can be performed. As a result, the controller 3 can perform appropriate control of the illuminance of ultraviolet 200.

[0055] As mentioned above, the inverse square law applies between the illuminance of ultraviolet 200 and the distance. Therefore, it is preferable that the distance between the detection unit 2 and the barrier discharge lamp 1 be approximately the same as the distance between the object to be processed and the barrier discharge lamp 1. For example, an adjustment mechanism can be provided to adjust the distance between the detection unit 2 and the barrier discharge lamp 1. The adjustment mechanism can be, for example, equipped with a screw mechanism. If an adjustment mechanism is provided, the illuminance of ultraviolet light irradiated onto the object can be detected with even greater accuracy.

[0056] Figure 5 is a schematic diagram illustrating a barrier discharge lamp 4 according to another embodiment. Figure 6 is a schematic cross-sectional view of the barrier discharge lamp 4 in the CC line direction in Figure 5. As shown in Figures 5 and 6, the barrier discharge lamp 4 includes, for example, a discharge tube 41, a reflective film 42 (corresponding to an example of a first reflective film), an electrode 43 (corresponding to an example of a first electrode), and an electrode 44 (corresponding to an example of a second electrode).

[0057] The discharge tube 41 is cylindrical in shape, with a length (length in the axial direction of the tube) that is longer than the diameter of the tube. For example, both ends of the discharge tube 41 are closed. When viewed from the X direction, the contour of the discharge tube 41 is, for example, approximately circular.

[0058] The length of the discharge tube 41 in the X direction can be appropriately set according to the dimensions of the required ultraviolet 200 irradiation area. The length (diameter) of the discharge tube 41 in the Y and Z directions is, for example, about 16 mm to 50 mm. The wall thickness of the discharge tube 41 is, for example, about 1.5 mm. The material of the discharge tube 41, the gas enclosed within it, and the sealing pressure can be the same as those for the discharge tube 11 described above.

[0059] Furthermore, a cover 41a can be provided to cover the end of the discharge tube 41. The cover 41a can be formed from an insulating material such as resin or ceramics.

[0060] The reflective film 42 is film-like and extends in the X direction. The reflective film 42 is provided on the inner wall of the discharge tube 41 and faces the electrode 43 across the discharge tube 41. The thickness and material of the reflective film 42 can be the same as those of the reflective film 12 described above. As shown in Figure 6, when viewed from the X direction, the reflective film 42 can be installed in a range where the central angle θ1 is approximately 180° to 300°.

[0061] Furthermore, similar to the case of the reflective film 12 described above, the reflective film 42 is provided with holes 42a that penetrate in the thickness direction. Therefore, ultraviolet light 200 generated in the internal space of the discharge tube 41 is incident on the light receiving part of the detection unit 2 described above through the holes 42a of the reflective film 42, the discharge tube 41, and the electrode 43.

[0062] The electrode 43 is provided on the outer wall of the discharge tube 41. The electrode 43 is provided on the side of the discharge tube 41 opposite to the side from which ultraviolet light 200 is emitted. The electrode 43 faces the reflective film 42, with the discharge tube 41 in between. Similar to the case of the electrode 13 described above, it is preferable that the electrode 43 be in close contact with the outer wall of the discharge tube 41. As shown in Figure 6, when viewed from the X direction, the electrode 43 can be positioned in a range where the central angle θ2 is approximately 180° to 300°.

[0063] Similar to electrode 13 described above, electrode 43 is capable of transmitting ultraviolet light 200. Electrode 43 has, for example, a lattice structure. The light-shielding rate of electrode 43 can be, for example, about the same as that of electrode 13 described above. The material and formation method of electrode 43 can be the same as those of electrode 13 described above.

[0064] The electrode 44 has, for example, a coil 44a and a leg 44b. The coil 44a and the leg 44b can be formed integrally. The coil 44a and the leg 44b can be formed, for example, by plastic deformation of a wire containing tungsten as the main component.

[0065] The coil 44a is spiral in shape and is provided in the internal space of the discharge tube 41. The coil 44a extends in the X direction through the central region of the internal space of the discharge tube 41. By providing the electrode 44 with the coil 44a in the internal space of the discharge tube 41, the distance between electrode 44 and electrode 43 can be shortened. Therefore, even if the contour of the discharge tube 41 viewed from the X direction is not flat, it becomes easy to generate a dielectric barrier discharge between electrode 43 and electrode 44.

[0066] Legs 44b are provided at each of the ends of the coil 44a. Legs 44b extend in the X direction from the ends of the coil 44a. Legs 44b are electrically connected to the controller 3 via lead wires 44c.

[0067] In the case of the barrier discharge lamp 4, a dielectric barrier discharge is performed between electrode 43 and electrode 44 to generate ultraviolet light 200 in the internal space of the discharge tube 41. The generated ultraviolet light 200 is emitted to the outside from the region of the discharge tube 41 where the reflective film 42 is not provided.

[0068] Here, the ultraviolet light 200 irradiated onto the object to be processed includes ultraviolet light 200 that is emitted directly through the discharge tube 41 and ultraviolet light 200 that is reflected by the reflective film 42 and then emitted through the discharge tube 41.

[0069] In contrast, if holes 42a are simply provided in the reflective film 42, the ultraviolet light 200 incident on the light receiving part of the detection unit 2 includes ultraviolet light 200 that is directly emitted through the discharge tube 41, the holes 42a in the reflective film 42, and the electrode 43, but hardly any ultraviolet light 200 that is reflected by the reflective film 42 is included.

[0070] Therefore, similar to the barrier discharge lamp 1 described above, a reflective film 42b is also provided on the inner wall of the discharge tube 41 on the side opposite to the electrode 43. As shown in Figures 5 and 6, the reflective film 42b is connected to the reflective film 42. In the X direction, the length of the reflective film 42b is shorter than the length of the reflective film 42. As shown in Figure 5, when viewed from the Z direction, the reflective film 42b is located near the end of the reflective film 42 on the side where the holes 42a are provided. In this case, the holes 42a of the reflective film 42 are located inside the reflective film 42b. The thickness and material of the reflective film 42b can be the same as those of the reflective film 42.

[0071] As shown in Figure 5, when viewed from the Z direction, in the region of the barrier discharge lamp 4 that irradiates ultraviolet light 200 toward the object to be processed, the electrode 43, discharge tube 41, reflective film 42, and electrode 44 (coil 44a) overlap.

[0072] When viewed from the Z direction, in the region of the barrier discharge lamp 1 where the illuminance of ultraviolet 200 is detected (the region where the detection unit 2 is provided), the electrode 43, discharge tube 41, reflective film 42b, and electrode 44 (coil 44a) overlap.

[0073] Therefore, the irradiation conditions of ultraviolet 200 irradiated onto the object to be processed and the irradiation conditions of ultraviolet 200 detected by the detection unit 2 are approximately the same, so the difference between the illuminance of ultraviolet 200 irradiated onto the object to be processed and the illuminance of ultraviolet 200 detected by the detection unit 2 can be reduced. In other words, appropriate detection of the illuminance of ultraviolet rays irradiated onto the object can be performed. As a result, the controller 3 can perform appropriate control of the illuminance of ultraviolet 200.

[0074] Furthermore, similar to the barrier discharge lamp 1 described above, an adjustment mechanism can be provided to adjust the distance between the detection unit 2 and the barrier discharge lamp 4. If an adjustment mechanism is provided, the illuminance of ultraviolet light irradiated onto the target object can be detected with even greater accuracy.

[0075] Although several embodiments of the present invention have been illustrated above, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. Furthermore, the embodiments described above can be implemented in combination with each other.

[0076] The following are additional notes regarding the embodiments described above.

[0077] (Note 1) A luminescent tube having a cylindrical shape with gas sealed inside; The first electrode provided on the outer wall of the light-emitting tube; A second electrode is provided on the outer wall of the light-emitting tube, or in the internal space of the light-emitting tube, and is opposite to the first electrode; A first reflective film is provided on the inner wall of the light-emitting tube and has holes that penetrate in the thickness direction; A second reflective film is provided on the inner wall of the light-emitting tube and faces the hole of the first reflective film; A barrier discharge lamp equipped with [a specific feature].

[0078] (Note 2) The first electrode is a barrier discharge lamp as described in Appendix 1, which is capable of transmitting ultraviolet light generated in the internal space of the discharge tube.

[0079] (Note 3) The barrier discharge lamp according to Appendix 1 or 2, wherein the holes in the first reflective film are facing the vicinity of one end of the first electrode.

[0080] (Note 4) A barrier discharge lamp according to any one of the appendices 1 to 3, wherein, when viewed from a direction in which the first electrode and the second electrode are facing each other, the holes in the first reflective film are located on the inside of the second reflective film.

[0081] (Note 5) A barrier discharge lamp as described in any one of the appendices 1 to 4; A detection unit for detecting ultraviolet light emitted through the pores of the first reflective film; A barrier discharge lamp module equipped with [a specific feature]. [Explanation of Symbols]

[0082] 1 Barrier discharge lamp, 2 Detection unit, 3 Controller, 4 Barrier discharge lamp, 11 Discharge tube, 12 Reflective film, 12a Hole, 12b Reflective film, 13 Electrode, 14 Electrode, 41 Discharge tube, 42 Reflective film, 42a Hole, 42b Reflective film, 43 Electrode, 44 Electrode, 100 Barrier discharge lamp module

Claims

1. A light-emitting tube having a cylindrical shape with gas sealed inside; The first electrode provided on the outer wall of the discharge tube; A second electrode is provided on the outer wall of the light-emitting tube or in the internal space of the light-emitting tube, and is opposite to the first electrode; A first reflective film provided on the inner wall of the light-emitting tube and having a hole penetrating in the thickness direction; A second reflective film is provided on the inner wall of the light-emitting tube and faces the hole of the first reflective film; A barrier discharge lamp equipped with [a specific feature].

2. The barrier discharge lamp according to claim 1, wherein the first electrode is capable of transmitting ultraviolet light generated in the internal space of the discharge tube.

3. The barrier discharge lamp according to claim 1 or 2, wherein the holes in the first reflective film are facing the vicinity of one end of the first electrode.

4. The barrier discharge lamp according to claim 1 or 2, wherein, when viewed from a direction in which the first electrode and the second electrode are facing each other, the holes in the first reflective film are located on the inside of the second reflective film.

5. A barrier discharge lamp according to claim 1 or 2; A detection unit for detecting ultraviolet light emitted through the pores of the first reflective film; A barrier discharge lamp module equipped with [a specific feature].

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