discharge tube

Abstract

A discharge tube comprises a container; an anode section having a plate-shaped form and an opening; a cathode section having a plate-shaped form and emitting photoelectrons in response to incident light passing through the opening; an anode electrode section having a rod-shaped form and extending along an alignment direction in which the anode section and the cathode section face each other; and a cathode electrode section having a rod-shaped form and extending along the alignment direction.If one side, where the anode section is located relative to the cathode section in the orientation direction, is defined as one side, and the other side opposite that side is defined as the other side, then the anode electrode section extends from the anode section to the other side, and the cathode electrode section extends from the cathode section to the other side. A junction area of ​​the cathode section with the cathode electrode section is exposed from one side, as viewed from the anode section, in the orientation direction.

Description

Technical field

[0001] The present invention relates to a discharge tube. State of the art

[0002] Patent document 1 describes a discharge tube for detecting ultraviolet rays, comprising an anode section, a cathode section, and a plurality of connecting wires, each connected to the anode section and the cathode section. In the fabrication of the discharge tube described in patent document 1, the cathode section is welded to the connecting wires, and then a spacer is placed between the cathode section and the anode section. Afterward, the anode section is welded to the connecting wires, and the spacer is removed. List of patent literature

[0003] Patent literature 1: Unexamined Japanese patent publication no. 2012-207971 Summary of the invention: Technical problem

[0004] The discharge tube described above requires a simplification of the manufacturing process. Furthermore, both the suppression of unintended discharges (abnormal discharges) and an improvement in detection accuracy are necessary.

[0005] Therefore, one aspect of the present invention provides a discharge tube which simplifies the manufacturing process of the discharge tube and improves the detection accuracy. Solution to the problem

[0006] A discharge tube according to one aspect of the present invention is [1] “a discharge tube” comprising: a container in which a discharge gas is enclosed; an anode section comprising a plate-shaped element in which an opening is formed and which is arranged in the container; a cathode section comprising a plate-shaped element in which the container is arranged facing the anode section and which emits photoelectrons in response to incident light through the opening; an anode electrode section having a rod-shaped form extending along an alignment direction in which the anode section and the cathode section face each other and is connected to the anode section; and a cathode electrode section having a rod-shaped form extending along the alignment direction and connected to the cathode section.If one side, where the anode section is located relative to the cathode section in the orientation direction in which the anode and cathode sections face each other, is defined as one side, and another side opposite that side is defined as the other side, then the anode electrode section extends from the anode section to the other side, and the cathode electrode section extends from the cathode section to the other side. A junction area of ​​the cathode section with the cathode electrode section is exposed in the orientation direction when viewed from the anode section.

[0007] In the discharge tube, the connection between the cathode section and the cathode electrode section is visible from the anode section when viewed from one side in the direction of alignment. Similarly, both the connection between the cathode section and the cathode electrode section, as well as the connection between the anode section and the anode electrode section, are visible from one side in the direction of alignment. Therefore, during the manufacturing of the discharge tube, the cathode section can be positioned relative to the cathode electrode section, and the anode section can be positioned relative to the anode electrode section. Subsequently, the connection between the cathode section and the cathode electrode section, as well as the connection between the anode section and the anode electrode section, can be carried out in a single process.This simplifies the manufacturing process compared to the manufacturing process described in patent literature 1 above, in which the cathode section is connected to the cathode electrode section, then the anode section is positioned relative to the anode electrode section, and then the anode section is connected to the anode electrode section. Furthermore, since the connection area of ​​the cathode section to the cathode electrode section in the discharge tube does not overlap the anode section in the orientation direction, the occurrence of an abnormal discharge due to overlap of the connection area with the anode section can be suppressed. Therefore, according to the discharge tube, the manufacturing process can be simplified and the detection accuracy improved.

[0008] A discharge tube according to one aspect of the present invention can be [2] “the discharge tube according to [1] in which the connection area is thinner than a part of the cathode section, the section surrounding the connection area”. In this case, the connection of the cathode section with the cathode electrode section can be facilitated.

[0009] A discharge tube according to one aspect of the present invention can be [3] “the discharge tube according to [2] in which the connection area is formed thinner than the section surrounding the connection area by forming a recess in the cathode section which is open to one side”. In this case, the recess can, for example, be used as a marker, and connecting the cathode section to the cathode electrode section can be facilitated.

[0010] A discharge tube according to one aspect of the present invention can be [4] “the discharge tube according to one of points [1] to [3], wherein the cathode section comprises a cutout section formed in an outer edge section, and the cutout section is exposed from one side in the orientation direction as seen from the anode section.” In this case, the occurrence of an abnormal discharge due to the overlap of the cutout section with the anode section can be suppressed.

[0011] A discharge tube according to one aspect of the present invention can be [5] “the discharge tube according to [4], wherein the cathode section further comprises a protruding section that projects from an inner surface of the cutout section, and the protruding section is located within the cutout section when viewed in the direction of orientation.” In this case, the occurrence of an abnormal discharge due to the protruding section projecting from the cutout section can be suppressed. Advantageous effects of the invention

[0012] According to one aspect of the present invention, it is possible to provide a discharge tube that can simplify the manufacturing process of the discharge tube and improve the detection accuracy. Brief description of the drawings [ Fig. 1] Fig. Figure 1 is a perspective view of a discharge tube according to one embodiment. [ Fig. 2] Fig. Figure 2 is a top view of the discharge tube. [ Fig. 3] Fig. Figure 3 is a top view of a discharge tube of a first modification example. [ Fig. 4] Fig. Figure 4 is a perspective view of a discharge tube of a second modification example. Description of embodiments

[0013] An embodiment of the present invention is described in detail below with reference to the drawings. Incidentally, the same reference numerals are used for identical or corresponding components in the following description, and duplicate descriptions are omitted.

[0014] According to the presentation in the Fig. 1 and Fig. 2 comprises a discharge tube 1, a container 10, an anode section 20, a cathode section 30, a pair of anode electrode sections 40, and a pair of cathode electrode sections 50. The anode section 20 and the cathode section 30 are arranged facing each other in the container 10. Hereinafter, one direction (orientation direction) in which the anode section 20 and the cathode section 30 face each other is defined as direction D1, and one side on which the anode section 20 is located with respect to the cathode section 30 in direction D1 is defined as a side S1 (a top side in Fig. 1) specified, and one side on which the cathode section 30 is located in relation to the anode section 20 in the direction of D1 is designated as the other side S2 (a bottom side in Fig. 1) specified. The discharge tube 1 is a sensor that detects ultraviolet radiation by utilizing the properties associated with the work function of the cathode section 30. The discharge tube 1 is used, for example, in applications such as flame detection, combustion monitoring, discharge detection, and as a safety device for the combustion of hydrogen or ammonia.

[0015] The container 10 comprises a stem 11 and a glass bulb 12. The stem 11 is, for example, formed in the form of an annular disc. An exhaust pipe 13 is connected to a central section of the stem 11. The glass bulb 12 is, for example, formed in a substantially cylindrical shape, with one end section (upper section) closed at one end S1 towards D1 and connected at the other end section (lower section) S2 towards D1 to an outer edge section of the stem 11. Accordingly, the interior of the container 10 is hermetically sealed. A discharge gas 2 is enclosed in the container 10. The glass bulb 12 is made, for example, of a material that is transparent to ultraviolet radiation. Examples of materials for the glass bulb 12 are borosilicate glass, ultraviolet-transmitting glass, quartz glass, and crystalline materials such as MgF₂.

[0016] The anode section 20 is formed from a metallic material in a flat, plate-like shape. For example, the anode section 20 is formed in a substantially rhombic shape when viewed along direction D1. In this example, the anode section 20 is formed in a substantially rhombic shape, with one diagonal being longer than the other, and the longer diagonal oriented along direction D2 in which the pair of anode electrode sections 40 face each other. Each corner section of the anode section 20 is curved in plan view so that it has no sharp upper section. The anode section 20 is made, for example, of tungsten, nickel, molybdenum, copper, stainless steel, Kovar metal, or the like.

[0017] A multitude of openings 21 (through holes) penetrating the anode section 20 along direction D1 are formed in a central section of the anode section 20. Each of the openings 21 is, for example, hexagonal in shape. The openings 21 are arranged regularly side by side in a two-dimensional pattern with regular spacing. In other words, the anode section 20 includes in its central section a substantially rhombus-shaped mesh section formed by the number of openings 21 provided along an outer edge section 20a of the anode section 20, and includes in its outer edge section a frame section surrounding the mesh section.Incidentally, the shape of the openings 21 can be a polygonal shape or a circular shape, which differs from a hexagonal shape, and the arrangement, size, number and the like of the openings 21 can also be selected in various forms depending on the application.

[0018] At each end section of the anode section 20, a recess 22 is formed in the direction of D2. In this example, the recesses 22 are open towards D1 on one side S1 and are circular when viewed in the direction of D1. The recesses 22 are formed, for example, by half-etching and are thinner than the parts of the anode section 20 that surround the recesses 22. Since, in the present embodiment, the plate material from which the anode section 20 is made has a uniform thickness, the recesses 22 are thinner than the parts of the anode section 20 that do not belong to the recesses 22 (with the exception of the openings 21). As will be described later, the anode section 20 is connected to the anode electrode sections 40 on the other side S2 in the direction of D1 at the positions of the recesses 22. This means that each of the recesses 22 forms a connection area R1 with the anode electrode section 40.

[0019] In the outer edge section 20a of the anode section 20, a plurality (in this example, four) cutout sections 23 are formed. These cutout sections 23 are sections where, for example, when the anode section 20 is formed during the manufacturing process by etching or the like in a metallic element having a plate shape, bridge sections are formed that connect the anode section 20 and the metallic element surrounding it. That is, each of the cutout sections 23 is a configuration required for the manufacturing process and does not function as an electrode. Furthermore, in the present embodiment, no bridge section remains in the anode section 20. Viewed in the direction D1, two cutout sections 23 are arranged on both sides of a recess 22 in a direction perpendicular to direction D2, such that they face each other.Viewed in the direction of D1, the two remaining cutout sections 23 are arranged on both sides of the other recess 22 in a direction perpendicular to direction D2, so that they face each other. Each of the cutout sections 23 is, for example, semicircular when viewed in the direction of D1.

[0020] The cathode section 30 is formed from a metallic material in a flat, plate-like shape. In this example, the cathode section 30 has the same shape as the anode section 20. That is, the cathode section 30 is essentially rhombus-shaped when viewed in the direction D1. The cathode section 30 is essentially rhombus-shaped, with one diagonal being longer than the other, and the longer diagonal oriented along a direction D3 in which the two cathode electrode sections 50 face each other. Each corner region of the cathode section 30 is curved in the top view so that it has no sharp upper edge. The cathode section 30 is made, for example, of tungsten, nickel, molybdenum, copper, Kovar metal, or the like.

[0021] In contrast to the anode section 20, no opening is formed in the cathode section 30. In the discharge tube 1, light that has passed through the openings 21 of the anode section 20 falls onto a surface 30b of the cathode section 30. The surface 30b is a flat surface of the cathode section 30 on one side S1 in the direction of D1 and functions as a photoelectric surface. The surface 30b emits photoelectrons in response to the incident light through the openings 21.

[0022] At each end section of the cathode section 30, a recess 32 is formed in the direction of D3. In this example, the recesses 32 are open towards D1 on one side S1 and are circular when viewed in the direction of D1. The recesses 32 are formed, for example, by half-etching and are thinner than the parts of the cathode section 30 that surround the recesses 32. Since the plate material of which the cathode section 30 is made has a uniform thickness in the present embodiment, the recesses 32 are thinner than the parts of the cathode section 30 that are not recesses 32. As will be described later, the cathode section 30 is connected to the cathode electrode sections 50 on the other side S2 in the direction of D1 at the positions of the recesses 32. That is, each of the recesses 32 forms a connection area R2 with the cathode electrode section 50.

[0023] In an outer edge section 30a of the cathode section 30, a plurality (in this example, four) cutout sections 33 are formed. Since the cutout sections 33 have the same configuration as the cutout sections 23, their description is omitted here. Viewed in the direction D1, two cutout sections 33 are arranged on either side of a recess 32 in a direction perpendicular to the direction D2, such that they face each other. Viewed in the direction D1, the two remaining cutout sections 33 are arranged on either side of the other recess 32 in a direction perpendicular to the direction D2, such that they face each other. Each of the cutout sections 33 is, for example, formed in a semicircular shape when viewed in the direction D1.

[0024] The anode sections 40 are rod-shaped electrode pins (trunk pins) that are positioned to penetrate and are attached to the trunk 11. The anode electrode sections 40 extend straight from the trunk 11 along direction D1. Viewed in direction D1, the pair of anode electrode sections 40 is arranged so that they face each other in direction D2, with the central section of the trunk 11 lying between them. The anode electrode sections 40 are made, for example, of Kovar metal.

[0025] Each of the anode electrode sections 40 is connected at an end section 40a on one side S1 in the direction of D1 to the connection area R1 of the anode section 20 and extends from the anode section 20 to the other side S2 in the direction of D1. Specifically, the end section 40a is connected to a section of a surface 20b of the anode section 20 on the other side S2 in the direction of D1, with the section overlapping the recess 22 in the direction of D1. In this example, the anode electrode sections 40 are connected to the anode section 20 by laser welding.

[0026] During welding, the anode section 20 is connected to each of the anode electrode sections 40, for example, by irradiating the recess 22 with laser light from one side S1 towards D1 in a state where the end section 40a is brought into contact with the anode section 20 on the other side S2 of the recess 22, and melting and solidifying at least one of the parts, namely the anode section 20 and the anode electrode section 40, at the recess 22. The pair of anode electrode sections 40 has the same height, and the anode section 20 is held by the pair of anode electrode sections 40 perpendicular to the direction D1. That is, the anode electrode sections 40 act as retaining elements that hold the anode section 20.

[0027] The cathode electrode sections 50 are rod-shaped electrode pins (trunk pins) that are positioned to penetrate and are attached to the trunk 11. The cathode electrode sections 50 extend straight from the trunk 11 along direction D1. Viewed in direction D1, the two cathode electrode sections 50 are arranged so that they face each other in direction D3, with the central section of the trunk 11 lying between them. The cathode electrode sections 50 are made, for example, of Kovar metal.

[0028] Each of the cathode electrode sections 50 is connected at an end section 50a on one side S1 in the direction of D1 to the connection area R2 of the cathode section 30 and extends from the cathode section 30 to the other side S2 in the direction of D1. Specifically, the end section 50a is connected to a section of a surface 30c of the cathode section 30 on the other side S2 in the direction of D1, with the section overlapping the recess 32 in the direction of D1. In this example, the cathode electrode sections 50 are connected to the cathode section 30 by laser welding.

[0029] During welding, the cathode section 30 is connected to each of the cathode electrode sections 50, for example, by irradiating the recess 32 with laser light from one side S1 towards D1 in a state where the end section 50a is brought into contact with the cathode section 30 on the other side S2 of the recess 32, and by melting and solidifying at least one of the parts, namely the cathode section 30 and the cathode electrode section 50, at the recess 32. The pair of cathode electrode sections 50 has the same height, and the cathode section 30 is held by the pair of cathode electrode sections 50 perpendicular to direction D1 and parallel to the anode section 20. That is, the cathode electrode sections 50 act as holding elements that hold the cathode section 30.According to the description above, the anode section 20 is arranged on one side S1 in the direction of D1 with respect to the cathode section 30. Therefore, the height of the pair of anode electrode sections 40 is greater than the height of the pair of cathode electrode sections 50.

[0030] In the discharge tube 1, the connection areas R2 of the cathode section 30 with the cathode electrode sections 50 are exposed from the anode section 20, viewed from one side S1 towards D1. That is, the anode section 20 is not located on one side S1 of the connection areas R2, and the connection areas R2 do not overlap the anode section 20 towards D1. Furthermore, viewed from one side S1 towards D1, the cutout sections 23 of the anode section 20 are exposed from the cathode section 30, and the cutout sections 33 of the cathode section 30 are exposed from the anode section 20.

[0031] The operation of the discharge tube 1 is described. In the operating state, a voltage is applied between the anode section 20 and the cathode section 30 via the anode electrode sections 40 and the cathode electrode sections 50. In the operating state, when ultraviolet light passes through the container 10 (glass bulb 12) and the openings 21 of the anode section 20 onto the cathode section 30 (surface 30b), photoelectrons are emitted from the cathode section 30. The photoelectrons are attracted to the anode section 20 and collide with discharge gas molecules in the container 10, thereby ionizing the discharge gas molecules. Of the electrons and positive ions produced by the ionization, the electrons repeatedly collide with other discharge gas molecules, ionizing them and reaching the anode section 20.Meanwhile, the positive ions are accelerated towards the cathode section 30 and collide with it, generating a large number of secondary electrons. The repetition of this phenomenon causes a current to flow between the anode section 20 and the cathode section 30, resulting in a discharge state. In the discharge tube 1, this discharge phenomenon is used to detect light in the ultraviolet range. [Functions and Effects]

[0032] In discharge tube 1, the connection areas R2 of the cathode section 30 with the cathode electrode sections 50 are exposed from the anode section 20, viewed from side S1 towards D1 (alignment direction). Accordingly, both the connection areas R2 of the cathode section 30 with the cathode electrode sections 50 and the connection areas R1 of the anode section 20 with the anode electrode sections 40 are visible from side S1 towards D1.Therefore, if the discharge tube 1 is manufactured by, for example, positioning the cathode section 30 in relation to the cathode electrode sections 50 and the anode section 20 in relation to the anode electrode sections 40, and then irradiation with laser light for laser welding is carried out from one side S1 towards D1, the joining of the cathode section 30 to the cathode electrode sections 50 and the joining of the anode section 20 to the anode electrode sections 40 can be carried out in a single process.This simplifies the manufacturing process compared to the manufacturing process described in the patent literature 1 above, in which the cathode section 30 is connected to the cathode electrode sections 50, then the anode section 20 is positioned relative to the anode electrode sections 40, and then the anode section 20 is connected to the anode electrode sections 40. Accordingly, the labor required for the manufacturing process can be reduced, and the discharge tubes 1 can be mass-produced. Furthermore, since in the discharge tube 1 the connection areas R2 of the cathode section 30 with the cathode electrode sections 50 do not overlap the anode section 20 in the direction of D1, the occurrence of an abnormal discharge due to an overlap of the connection areas R2 with the anode section 20 can be suppressed.Therefore, according to discharge tube 1, the manufacturing process of the discharge tube can be simplified and the detection accuracy improved. Furthermore, since the anode section 20 and the cathode section 30 in discharge tube 1 consist of flat, plate-shaped elements, the number of processes that could lead to deformation of the elements can be reduced, for example, compared to cases where the anode and cathode sections have curved sections. Therefore, the accuracy of the distance between the anode section 20 and the cathode section 30 can be improved.

[0033] The connection areas R2 are formed thinner than the parts of the cathode section 30 that surround the connection areas R2. Accordingly, the connection of the cathode section 30 to the cathode electrode sections 50 can be facilitated. For example, if the cathode section 30 is connected to the cathode electrode sections 50 by laser welding, the formation of the connection areas R2, which are thinner than the parts of the cathode section 30 that surround the connection areas R2, allows the laser welding to be performed with lower power than if the connection areas R2 were not thinner. Therefore, the connection of the cathode section 30 to the cathode electrode sections 50 can be facilitated.Furthermore, the connection of the anode section 20 with the anode electrode sections 40 can be facilitated by making the connection areas R1 thinner than the parts of the anode section 20 that do not belong to the connection areas R1.

[0034] The connection areas R2 are formed thinner than the areas surrounding them by the recesses 32 in the cathode section 30, which are open towards one side S1. In this case, the recesses 32 can be used as markers, for example, and the joining of the cathode section 30 to the cathode electrode sections 50 can be facilitated. For example, if the cathode section 30 is joined to the cathode electrode sections 50 by laser welding from one side S1 of the cathode section 30, the recesses 32 serve as markers for the weld points, so that the weld points can be easily identified compared to cases where the recesses 32 are not provided. Therefore, the joining of the cathode section 30 to the cathode electrode sections 50 can be facilitated.Since the recesses 32 are formed such that they open towards one side S1, the connection areas R2 are further away from the anode section 20 in the direction of D1 than the areas that do not belong to the connection areas R2. Even if deformations or similar occur in the connection areas R2 due to the connection, a reduction in the distance to the anode section 20 in the direction of D1 can be suppressed. This reduces the possibility of discharge due to the connection areas R2. Furthermore, the connection areas R1 are thinner than the other areas formed by the recesses 22 in the anode section 20, which are open towards one side S1. In this case, the recesses 22 can be used as markers, and connecting the anode section 20 to the anode electrode areas 40 can be facilitated.

[0035] The cathode section 30 comprises the cutout sections 33 formed in the outer edge section 30a, and the cutout sections 33 are exposed from one side S1 towards D1, as viewed from the anode section 20. Accordingly, the occurrence of an abnormal discharge due to the overlap of the cutout sections 33 with the anode section 20 can be suppressed. If the cutout sections 33 overlap the anode section 20, there is a possibility of an abnormal discharge occurring between the cutouts 33 and the anode section 20; however, according to the cathode section 30 in the present embodiment, the occurrence of such an abnormal discharge can be suppressed. Furthermore, the anode section 20 comprises the cutout sections 23 formed in the outer edge section 20a, and the cutout sections 23 are exposed from the other side S2 towards D1, as viewed from the cathode section 30.Accordingly, the occurrence of an abnormal discharge due to the cutout sections 23, which overlap the cathode section 30, can be suppressed. [Modification examples]

[0036] In a first modification example, which according to the representation in Fig. As shown in Figure 3, the anode section 20 includes a projecting section 24 that extends from an inner surface of each of the cutout sections 23. The projecting section 24 is, for example, a burr that arises when the anode section 20 is cut off from a metal element during the manufacturing process of the anode section 20, and is part of the bridge section described above that remains in the anode section 20. Viewed along direction D1, the projecting section 24 is located within the cutout section 23. That is, viewed along direction D1, the projecting section 24 is located within the outer edge section 20a (an outer edge if the cutout section 23 is assumed not to be formed) of the anode section 20.

[0037] Furthermore, the cathode section 30 includes a projecting section 34 that extends from an inner surface of each of the cutout sections 33. The projecting section 34 is, for example, a burr that arises when the cathode section 30 is cut off from a metal part during the manufacturing process of the cathode section 30, and is part of the bridge section described above that remains in the cathode section 30. Viewed in the direction D1, the projecting section 34 is located inside the cutout section 33. That is, viewed in the direction D1, the projecting section 34 is located inside the outer edge section 30a (an outer edge if the cutout section 33 is assumed not to be formed) of the cathode section 30.

[0038] In the first modification example, the protruding section 34 is located within the cutout section 33 when viewed in the direction of D1. Accordingly, the occurrence of an abnormal discharge due to the protruding section 34 extending from the cutout section 33 can be suppressed. If the protruding section 34 is not located within the cutout section 33, an abnormal discharge can occur between the protruding section 34 and the anode section 20; however, according to the first modification example, the occurrence of such an abnormal discharge can be suppressed.

[0039] The discharge tube 1 can be used as in a second modification example in Fig. 4 trained. In Fig.In the second modification example, the glass bulb 12 is omitted. Viewed from the direction of D1, the anode section 20 and the cathode section 30 are essentially triangular. Three anode electrode sections 40 are connected to the anode section 20, and the anode section 20 has three connection areas R1. Furthermore, the anode section 20 includes six cutout sections 23. Similarly, three cathode electrode sections 50 are connected to the cathode section 30, and the cathode section 30 has three connection areas R2. In addition, the cathode section 30 includes six cutout sections 33. Also in the second modification example, the connection areas R2 of the cathode section 30 with the cathode electrode sections 50 are exposed from the anode section 20 on one side S1 in the direction of A.In the second modification example, similar to the embodiment described above, the manufacturing process of the discharge tube can be simplified and the detection accuracy improved.

[0040] The present invention is not limited to the embodiment and modification examples described above. For example, the material and shape of each configuration are not limited to those described above, and different materials and shapes can be used.

[0041] In the embodiment described above, the cathode electrode sections 50 are connected to the surface 30c on the other side S2 of the cathode section 30; however, the cathode electrode sections 50 can also be connected to the surface 30b on one side S1 of the cathode section 30. For example, the cathode electrode sections 50 can be arranged to penetrate the cathode section 30, and they can be connected to the surface 30b on one side S1 of the cathode section 30 at sections that protrude from the cathode section 30. That is, the cathode electrode sections 50 need only be connected to one of the surfaces 30b on one side S1 and the surface 30c on the other side S2 of the cathode section 30.From the perspective of suppressing abnormal discharges or the like, it is preferred if the cathode electrode sections 50 are connected to the surface 30c on the other side S2 of the cathode section 30, as in the embodiment described above. Likewise, the anode electrode sections 40 can be connected to a surface on one side S1 of the anode section 20 and need only be connected to one of the surfaces on one side S1 and the surface 20b on the other side S2 of the anode section 20. Furthermore, the cathode electrode sections 50 and the cathode section 30, as well as the anode electrode sections 40 and the anode section 20, are not limited to being connected directly by welding or the like, but can, for example, be connected indirectly using a joining material such as a brazing alloy.

[0042] The recesses 32 need not be formed in the cathode section 30, and the cathode section 30 can have the same thickness along its entire length. The recesses 22 need not be formed in the anode section 20, and the anode section 20 can have the same thickness along its entire length. The recesses 32 of the cathode section 30 can be formed so that they open towards the other side S2. The recesses 22 of the anode section 20 can be formed so that they open towards the other side S2. The cutout sections 33 of the cathode section 30 can overlap the anode section 20 when viewed from one side S1 towards D1. The cutout sections 33 need not be formed in the cathode section 30. The cutout sections 23 need not be formed in the anode section 20.In the first modification example, the projecting section 34 of the cathode section 30 can include a section that, viewed in the direction of D1, lies outside the cutout 33. In the first modification example, the projecting section 24 of the anode section 20 can include a section that lies outside the cutout section 33 when viewed in the direction of D1. List of reference symbols

[0043] 1: Discharge tube, 10: Container, 20: Anode section, 21: Opening, 30: Cathode section, 30a: Outer edge section, 32: Recess, 33: Cutout section, 34: Projecting section, 40: Anode electrode section, 50: Cathode electrode section, D1: Direction (alignment direction), R2: Connection area. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2012-207971

[0003]

Claims

[1] Discharge tube comprising: a container in which a discharge gas is enclosed; an anode section consisting of a plate-shaped element in which an opening is formed and which is arranged in the container; a cathode section consisting of a plate-shaped element facing the container and emitting photoelectrons in response to the incident light passing through the opening; an anode electrode section having a rod shape and extending along an orientation direction in which the anode section and the cathode section face each other, and which is connected to the anode section; and a cathode electrode section which has a rod shape and extends along the alignment direction and is connected to the cathode section, wherein, if one side on which the anode section is located in relation to the cathode section in the orientation direction in which the anode section and the cathode section face each other is defined as one side, and one side opposite that side is defined as the other side, the anode electrode section extends from the anode section to the other side, and the cathode electrode section extends from the cathode section to the other side, and wherein a connection area of ​​the cathode section with the cathode electrode section is exposed from the anode section in the direction of orientation when viewed from one side. [2] Discharge tube according to claim 1, wherein the connection area is thinner than a section of the cathode section, the section surrounding the connection area. [3] Discharge tube according to claim 2, wherein the connection area is thinner than the section surrounding the connection area by forming a recess in the cathode section which is open to one side. [4] Discharge tube according to one of claims 1 to 3, wherein the cathode section has a cut-out section formed in an outer edge section, and where the cut-out section is exposed on one side in the direction of alignment, as seen from the anode section. [5] Discharge tube according to claim 4, wherein the cathode section further comprises a projecting section that protrudes from an inner surface of the cut-out section, and where the protruding section, viewed in the direction of orientation, is located within the cut-out section.

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