X-ray generating device

Abstract

In an X-ray generating apparatus (101) in which an X-ray tube (102) is grounded to a protruding portion (107c) of a container (107), discharge between the X-ray tube (102) and the container (107) is reduced. The container (107) includes the protruding portion (107c) so that, in an axial direction Dt, a bent portion (107d) is positioned between an anode-side joint portion (128) at which an insulating tube (4) and an anode (103) are joined to each other and a cathode-side joint portion (122) at which the insulating tube (4) and a cathode (104) are engaged to each other.

Description

[0001] This divisional application is based on Chinese patent application No. 201780051938.8, filed on September 28, 2017, entitled "X-ray Generating Device", which is the Chinese national phase application WO2018 / 079176. Technical Field

[0002] This invention relates to an X-ray generating apparatus including an X-ray tube. Background Technology

[0003] Some existing X-ray generating devices include an X-ray tube with a transmission target. This type of X-ray generating device has a grounded metal container filled with an insulating liquid, and the X-ray tube and the driving circuitry for driving the X-ray tube are housed within the metal container. This structure, where the X-ray tube is housed within a metal container, is called a monotank structure. The monotank structure allows for a smaller size and higher reliability in X-ray generating devices, making discharge less likely even when high tube voltages are applied.

[0004] Typically, in X-ray generating equipment with a single-tank structure, the potential of the X-ray tube's anode and cathode relative to the grounded metal container is determined by using either a neutral grounding method or an anode grounding method.

[0005] In X-ray generating equipment using a neutral-point grounding method, a bipolar voltage source applies +1 / 2 Va and -1 / 2 Va to the anode and cathode of the X-ray tube, respectively, thereby applying the tube voltage Va. In this neutral-point grounding method, the X-ray tube, including the anode, is installed in a state where it is completely immersed in an insulating liquid.

[0006] Patent document 1 describes an X-ray generating device that includes a transmission X-ray tube using a neutral point grounding method and has a single-tank structure.

[0007] Using the neutral point grounding method described in Patent Document 1, the maximum voltage difference between the common ground electrode and the metal container is half the tube voltage Va. This method facilitates the reduction in size and high electrical reliability of X-ray generating equipment.

[0008] On the other hand, X-ray generating equipment that is suitable for reducing size and using a neutral grounding method is not suitable for magnified imaging because the X-ray target is set in a container and therefore the reduction in distance between the X-ray generator and the object is limited.

[0009] In X-ray generating equipment using anode grounding, the anode of the X-ray tube and the metal container are grounded, and a unipolar voltage source applies a potential of -Va (negative tube voltage) to the cathode. The anode can be considered as part of the metal container or a single tank. Therefore, in X-ray tubes using anode grounding and mounted in a container, the anode is partially exposed to the outside of the single tank, while the insulating tube and cathode are completely immersed in an insulating liquid.

[0010] In X-ray generating equipment using an anode-grounded transmission X-ray tube, the X-ray target is positioned on the wall surface of a metal container or outside the metal container. Therefore, the X-ray generator can be positioned close to the object, and the X-ray generating equipment is suitable for magnified imaging. Typically, the magnification is determined by the ratio of the distance between the X-ray generator and the X-ray detection surface (SID) to the distance between the X-ray generator and the object (SOD). Here, "SID" and "SOD" are abbreviations for "source-to-image receiver distance" and "source-to-object distance," respectively. Patent Document 2 describes an X-ray generating equipment with a single-tank structure, wherein the anode of the anode-grounded transmission X-ray tube protrudes outside the container.

[0011] Citation List

[0012] Patent documents

[0013] [Patent Document 1] US Patent No. 7949099

[0014] [Patent Document 2] Japanese Patent Application Publication No. 2015-58180 Summary of the Invention

[0015] [Technical Issues]

[0016] The X-ray generating apparatus described in Patent Document 2 (in which the anode of the anode-grounded transmission X-ray tube protrudes to the outside of the container) has the following problem: the X-ray generating apparatus may not be able to simultaneously reduce SOD and stably apply tube voltage, and therefore at least one of magnified imaging and stable imaging may be limited.

[0017] [Technical Solution]

[0018] The present invention provides an X-ray generating apparatus capable of magnified imaging in which the discharge between the X-ray tube and the container is reduced.

[0019] [Solution to the problem]

[0020] According to the present invention, an X-ray generating apparatus includes an X-ray tube and a conductive container housing the X-ray tube. The X-ray tube includes a cathode comprising an electron emission source, an anode comprising a transmission target, and an insulating tube connected to each of the anode and the cathode. The container includes a flange portion extending toward the insulating tube, the flange portion projecting from the flange portion, and the anode being secured to the flange portion.

[0021] Other features of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0022] Figure 1A This is a cross-sectional view of an X-ray generating apparatus according to a first embodiment of the present invention.

[0023] Figure 1B This is a front view of an X-ray generating apparatus according to a first embodiment of the present invention.

[0024] Figure 1C This is a top view of an X-ray generating apparatus according to a first embodiment of the present invention.

[0025] Figure 1D This is a side view of an X-ray generating apparatus according to a first embodiment of the present invention.

[0026] Figure 2A This is a perspective view of an X-ray generating apparatus according to a second embodiment of the present invention.

[0027] Figure 2B A cross-sectional view (a) of an X-ray generating apparatus according to a second embodiment of the present invention is shown, along with graphs (b), (c), and (d) relating to the distance between the inner surface of the container and the insulating tube.

[0028] Figure 3A This is a perspective view of an X-ray generating apparatus according to a third embodiment of the present invention.

[0029] Figure 3B A cross-sectional view (a) of an X-ray generating apparatus according to a third embodiment of the present invention is shown, along with graphs (b), (c), and (d) relating to the distance between the inner surface of the container and the insulating tube.

[0030] Figure 4A This is a cross-sectional view showing the main parts of the fourth embodiment of the present invention.

[0031] Figure 4B This is a cross-sectional view showing the main parts of the fifth embodiment of the present invention.

[0032] Figure 4CThis is a cross-sectional view showing the main parts of the sixth embodiment of the present invention.

[0033] Figure 4D This is a perspective view of the protective components.

[0034] Figure 5A This is a cross-sectional view showing the anode-side connection portion and the cathode-side connection portion of an X-ray tube according to a seventh embodiment of the present invention.

[0035] Figure 5B This is a cross-sectional view showing the anode-side connection portion and the cathode-side connection portion of an X-ray tube according to an eighth embodiment of the present invention.

[0036] Figure 6 This is a block diagram illustrating an X-ray imaging system according to a ninth embodiment of the present invention. Detailed Implementation

[0037] Embodiments of the present invention will now be described with reference to the accompanying drawings.

[0038] [First Embodiment]

[0039] X-ray generating equipment

[0040] Figure 1A This is a cross-sectional view of an X-ray generating apparatus 101 according to a first embodiment of the present invention. Figures 1B to 1D These are the front view, top view, and side view of the X-ray generating apparatus 101. In this specification and the accompanying drawings, the z-axis extends along the axial direction Dt of the X-ray tube, while the xy-plane extends along the radial direction of the X-ray tube. The z-coordinate of the emitting surface of the transmission target is 0. The direction in which X-rays are emitted from the container 107 is the positive z-direction, while the direction towards the cathode 104 is the negative z-direction. In other words, the direction from the cathode 104 towards the anode 103 is the positive z-direction.

[0041] X-ray generating apparatus 101 includes an X-ray tube 102, an insulating liquid 108, and a container 107 for containing the X-ray tube 102 and the insulating liquid 108. A key feature of this invention is the specific positional relationship between the container 107 and the X-ray tube 102. This positional relationship will be described below.

[0042] [X-ray tube]

[0043] The X-ray tube 102 according to the first embodiment is a transmission X-ray tube. The X-ray tube 102 includes an anode 103 having a transmission target 1, a cathode 104 having an electron emission source 9, and an insulating tube 4. The insulating tube 4 is connected to the anode 103 and the cathode 104 at one end and the other end, respectively, and the anode 103 and the cathode 104 are mutually insulated. The insulating tube 4, the anode 103, and the cathode 104 form a vacuum-sealed container.

[0044] The anode 103 includes a transmission target 1 and an annular anode member 2. The transmission target 1 includes a target layer 1a and a support window 1b supporting the target layer 1a. The anode member 2 is electrically connected to the target layer 1a and connected to the support window 1b. The anode member 2 and the support window 1b are sealed along an annular line using brazing material.

[0045] The target layer 1a, comprising heavy metals such as tungsten and tantalum, generates X-rays when irradiated with electrons. The thickness of the target layer 1a is determined based on the balance between the penetration depth of electrons that contribute to X-ray generation and the self-attenuation of the generated X-rays passing through the target layer 1a toward the support window 1b. This thickness can range from 1 μm to tens of μm.

[0046] The support window 1b functions as an end window, transmitting and emitting X-rays generated in the target layer 1a to the outside of the X-ray tube 102. The support window 1b is made of a material capable of transmitting X-rays. Examples of such materials include beryllium, aluminum, silicon nitride, and isotopes of carbon. The support window 1b can be made of diamond, which has high thermal conductivity, thereby effectively transferring heat from the target layer 1a to the anode member 2.

[0047] The insulating tube 4 is made of a material with vacuum-sealing and insulating properties. Examples of such materials include ceramic materials (e.g., alumina and zirconium oxide) and glass materials (e.g., sodium calcium and quartz). To reduce thermal stress between the insulating tube 4 and the cathode member 8 and anode member 2, the cathode member 8 and anode member 2 are made of materials whose linear expansion coefficients αc (ppm / ℃) and αa (ppm / ℃) are close to the linear expansion coefficient αi (ppm / ℃) of the insulating tube 4. Examples of such materials include alloys, such as Kovar and Monel.

[0048] In this specification, the axial direction Dt and axis Ct of the X-ray tube 102 are defined as the axial direction and axis of the insulating tube 4.

[0049] The cathode 104 includes an electron emission source 9 and a cathode member 8. The electron emission source 9 includes a head portion 23 having an electron emitter and a neck portion 22 fixing the head portion to the cathode member 8. The cathode member 8 is annular and connected to the electron emission source 9.

[0050] The electron emission source 9 is brazed to the cathode component 8 using brazing material or thermally fused to the cathode component 8 by means of laser welding or the like. The head portion 23 of the electron emission source 9 includes an electron emitter, such as an immersion thermionic source, a filament thermionic source, or a cold cathode source. The head portion 23 may include electrodes (not shown) defining an electrostatic field, such as lead-out grid electrodes or converging lens electrodes. The neck portion 22 is shaped like a hollow cylinder or multiple cylinders extending in the axial direction, allowing wires electrically connected to the electron emitter and the electrostatic lens electrodes to extend through it.

[0051] The X-ray tube 102 according to the first embodiment is a transmission X-ray tube. For example... Figure 1A As shown, the X-ray tube 102 is fixed to the container 107 for anode grounding. The anode 103 of the X-ray tube 102 is grounded by being electrically connected to the grounding terminal 105 through the conductive container 107. The cathode 104 of the X-ray tube 102 is electrically connected to the negative electrode terminal of the tube drive circuit 106 and electrically connected to the grounding terminal through the positive electrode terminal of the tube drive circuit 106. The tube drive circuit 106 includes a tube voltage driver (not shown) that outputs a tube voltage Va. The potential of the positive electrode terminal of the tube drive circuit 106 is defined as the ground potential, and the negative electrode terminal of the tube drive circuit 106 outputs a potential -Va (V). The tube drive circuit 106 includes an electron quantity controller (not shown) that controls the number of electrons emitted from the electron emitter.

[0052] [container]

[0053] Container 107 has a sealed structure and contains an insulating liquid 108, an X-ray tube 102, and a tube drive circuit 106. Container 107 includes a rear receiving portion 107a, a flange portion 107b, and a protruding portion 107c that accommodate the tube drive circuit 106. The rear receiving portion 107a and the flange portion 107b are sealed along a closed line to form a liquid seal. The flange portion 107b and the protruding portion 107c are sealed along an annular line to form a liquid seal.

[0054] In the first embodiment, each of the rear receiving portion 107a, the flange portion 107b, and the protrusion portion 107c is conductive, allowing the entire container 107 to have the same potential (ground potential). Grounding the container 107 in this manner ensures the electrical stability of the X-ray generating apparatus 101. Considering conductivity and strength, each of the rear receiving portion 107a, the flange portion 107b, and the protrusion portion 107c can be made of a metallic material.

[0055] The container 107 is vacuum-filled with insulating liquid 108 to prevent air bubbles from forming between the X-ray tube 102 and the tube drive circuit 106. This is because air bubbles in the insulating liquid 108 are regions with a dielectric constant lower than that of the surrounding area and could potentially cause discharge. The insulating liquid 108 facilitates heat exchange via convection due to uneven temperature distribution among the components disposed within the container. The insulating liquid 108 also reduces uneven temperature distribution within the container 107; allows heat in the container 107 to dissipate to the outside through the walls of the container 107; and reduces discharge between the X-ray tube 102, the tube drive circuit 106, and the container 107. Specifically, a fluid with heat resistance, flowability, and electrical insulation properties corresponding to the operating temperature range of the X-ray generating equipment 101 is used as the insulating liquid 108. Examples of such fluids include chemically synthesized oils such as silicone oil or fluoropolymer oil; mineral oil; and insulating gases such as SF6.

[0056] [The positional relationship between the various parts of the container and the X-ray tube]

[0057] refer to Figures 1A to 1D The positional relationship between the X-ray tube 102 according to the invention and the rear receiving portion 107a, flange portion 107b and protrusion portion 107c of the container will be described.

[0058] The X-ray generating apparatus 101 according to the first embodiment includes a protrusion 107c having a cylindrical shape, and the anode 103 of the X-ray tube 102 is connected to the protrusion 107c.

[0059] The anode 103 of the X-ray tube 102 is connected to an opening formed in the cylindrical protrusion 107c, thereby securing the X-ray tube 102 to the container 107. The tube drive circuit 106 is secured to the rear receiving portion 107a of the container using a fixing member (not shown). By dividing the rear receiving portion 107a, which is continuous along the closed line with the flange portion 107b, into a portion for securing and receiving the X-ray tube 102 and a portion for securing the tube drive circuit 106, the X-ray tube 102 can be selectively disposed within the protrusion 107c of the container 107.

[0060] If in such Figure 6 In the X-ray imaging system shown, the anode of the X-ray tube is fixed to a container without protrusions. The portion of the container facing the object and close to the object will have a larger area, and it will be difficult to reduce the source-to-image receiver distance (SID).

[0061] Conversely, container 107 includes a flange portion 107b that is continuous with the rear receiving portion 107a along a closed line. The flange portion extends from the portion continuous with the rear receiving portion 107a toward and surrounds the insulating tube 4. Container 107 also includes a protrusion 107c that is continuous with the flange portion 107b along a circular line. The protrusion includes a portion projecting from the flange portion 107b in a direction away from the rear receiving portion 107a, and the anode 103 is fixed to the protrusion. Container 107 includes a curved portion 107d between the protrusion 107c and the flange portion 107b. The protrusion 107c and the flange portion 107b are continuous with each other along a circular line, wherein the curved portion 107d, extending circumferentially along the inner surface of container 107, is located between the protrusion and the flange portion. In other words, the curved portion 107d is positioned in the portion of container 107 that protrudes into container 107. In other words, the flange portion 107b extends circumferentially, such that the curved portion 107d surrounds the insulating tube 4.

[0062] Since the protrusion 107c protrudes from the flange portion 107b and has a bend 107d between them, the transmission target 1 can be positioned at the end of the protrusion 107c of the container 107, where the electron beam is focused and X-rays are generated.

[0063] Therefore, when the X-ray generating apparatus 101 according to the present invention is used in Figure 6 In the X-ray imaging system 200 shown, the X-ray imaging system 200 can have high magnification and effectively perform high-resolution imaging. That is, between the X-ray generating device 101 and the X-ray detector 206, the source-to-object distance SOD can be effectively reduced relative to the source-to-image receiver distance SID, for which the detection surface area of ​​the X-ray detector 206 is practically limited; and the magnification SID / SOD can be increased. Therefore, the transmission target 1 (the X-ray generator of the X-ray generating device 101) can be positioned close to the region of interest (ROI) of the object 204 having a portion protruding toward the X-ray generating device 101, while preventing collision between the X-ray generating device 101 and the object 204. An example of the object 204 with the protruding portion includes a semiconductor substrate on which multiple devices of different heights are mounted.

[0064] like Figure 1AAs shown, in the axial direction Dt (z direction), the bent portion 107d is positioned between the anode-side connection portion 128 (where the insulating tube 4 and the anode 103 are connected to each other) and the cathode-side connection portion 122 (where the insulating tube 4 and the cathode 104 are connected to each other). By arranging the X-ray tube 102 in the container 107 in this way, an X-ray generating device 101 capable of performing magnified imaging and possessing high reliability can be provided. In other words, the technical advantage of arranging the transmission target 1 at a protruding position in the container 107 is that it is suitable for magnified imaging. Moreover, since the bent portion 107d, which has the same potential as the anode, is arranged to be separated from the cathode 104, discharge can be reduced and the reliability of the X-ray generating device 101 can be ensured. This arrangement is equivalent to separating the bent portion 107d, which has the same potential as the anode, from the three points (the connection portion between the cathode 104 and the insulating tube 4), and thus reducing the discharge of the X-ray generating device 101.

[0065] Note that the statement “the protruding portion 107c protrudes from the flange portion 107b and has a curved portion 107d between them” has essentially the same meaning as the statement “the container 107 includes a flange portion that extends from a portion of itself that is continuous with the rear receiving portion 107a along the closure line toward and surrounds the insulating tube 4”.

[0066] Figure 2A This is a perspective view of an X-ray generating apparatus 101 according to a second embodiment of the present invention. Figure 2B A cross-sectional view (a) of the X-ray generating apparatus 101 and graphs (b), (c), and (d) relating to the distance between the inner surface of the container 107 and the insulating tube 4 are shown. Figure 2B In the same manner as in the other figures of this specification, the direction from the cathode 104 toward the anode 103 is defined as the positive z-direction, and the position of the inner surface of the container 107 along the axial direction Dt is represented by z.

[0067] The X-ray generating apparatus 101 according to the second embodiment includes a protruding portion 107c having a cuboid shape. The second embodiment differs from the first embodiment in the shapes of the flange portion 107b, the protruding portion 107c, and the curved portion 107d. In the second embodiment, the curved portion 107d is rectangular and surrounds the insulating tube 4.

[0068] exist Figure 2B In diagram (b), the distance Li between the insulating tube 4 and the inner circumferential surface of the container 107 is plotted relative to the position z in the axial direction. Figure 2B In graph (c), the first derivative of the distance Li with respect to position z is plotted relative to position z. Similarly, in Figure 2BIn the graph (d), the second derivative of distance Li with respect to position z is plotted with respect to position z.

[0069] like Figure 2B As shown in the cross-sectional views (a) and diagram (c), the location where the local minimum of the first derivative of the distance Li between the insulating tube 4 and the container 107 with respect to position z coincides with the location of the bend 107d. Figure 2B As shown in the cross-sectional view (a) and diagram (d), the location where the sign of the second derivative of the distance Li between the insulating tube 4 and the container 107 with respect to position z changes from negative to positive coincides with the location of the curved portion 107d. Therefore, even though the container 107 includes portions with finite radii of curvature, the location of the curved portion 107d can be uniquely determined.

[0070] Figure 3A This is a perspective view of an X-ray generating apparatus 101 according to a third embodiment of the present invention. Figure 3B A cross-sectional view (a) of the X-ray generating apparatus 101 and graphs (b), (c), and (d) relating to the distance between the inner surface of the container 107 and the insulating tube 4 are shown. The X-ray generating apparatus 101 according to a third embodiment includes a protrusion 107c having a truncated conical shape. The third embodiment differs from the first embodiment in the shape of the protrusion 107c, and from the second embodiment in the shapes of the flange portion 107b, the protrusion 107c, and the curved portion 107d. In the third embodiment, the curved portion 107d is annular and surrounds the insulating tube 4, as in the first and second embodiments.

[0071] exist Figure 3B In diagram (b), the distance Li between the insulating tube 4 and the inner circumferential surface of the container 107 is plotted relative to the position z in the axial direction. Figure 3B In graph (c), the first derivative of the distance Li with respect to position z is plotted relative to position z. Similarly, in Figure 3B In the graph (d), the second derivative of distance Li with respect to position z is plotted with respect to position z.

[0072] Similarly, in the third embodiment, such as Figure 3B As shown in the cross-sectional views (a) and diagram (c), the location where the local minimum of the first derivative of the distance Li between the insulating tube 4 and the container 107 with respect to position z coincides with the location of the bend 107d. Figure 3B As shown in the cross-sectional view (a) and diagram (d), the position where the sign of the second derivative of the distance Li between the insulating tube 4 and the container 107 with respect to position z changes from negative to positive coincides with the curved portion 107d.

[0073] Figures 4A to 4CThis is a partially enlarged cross-sectional view of the main part of the X-ray generating apparatus 101 according to the fourth, fifth and sixth embodiments of the present invention. Figures 4A to 4C Cathode-side connection portion 122 and anode-side connection portion 128 of an X-ray generating apparatus 101 according to one of the corresponding embodiments of the fourth to sixth are shown. Cathode 104 (cathode member 8) and insulating tube 4 are connected to each other at cathode-side connection portion 122. Anode 103 (anode member 2) and insulating tube 4 are connected to each other at anode-side connection portion 128.

[0074] exist Figure 4A In the fourth embodiment shown, the distance Lcb between the cathode-side connection portion 122 and the curved portion 107d is greater than the distance Lca between the cathode-side connection portion 122 and the anode-side connection portion 128. The fourth embodiment (where the protruding length of the protruding portion 107c is smaller) may be affected by the height of the object (not shown) when capturing a magnified image of the object. Therefore, the fourth embodiment is not particularly suitable for magnified imaging compared to the fifth and sixth embodiments described below. On the other hand, in the fourth embodiment, the cathode-side connection portion 122, which forms the tri-point where the electric field concentration occurs, is not closer to the curved portion 107d than the anode-side connection portion 128. Therefore, discharge between the cathode 104 and the container 107 is unlikely to occur. In the fourth embodiment, the distance between the curved portion 107d and the cathode-side connection portion 122 can be equal to the distance between the anode-side connection portion 128 and the cathode-side connection portion 122.

[0075] exist Figure 4B In the fifth embodiment shown, the distance Lcb between the cathode-side connection portion 122 and the curved portion 107d is less than the distance Lca between the cathode-side connection portion 122 and the anode-side connection portion 128. Compared to the fourth embodiment, the fifth embodiment (in which the protruding length of the protruding portion 107c is longer) is less likely to be affected by the height of the object (not shown) when capturing a magnified image of the object. Therefore, the fifth embodiment is more suitable for magnified imaging than the fourth embodiment. On the other hand, in the fifth embodiment, the cathode-side connection portion 122, which forms the tri-point where the electric field concentration occurs, is closer to the curved portion 107d than the anode-side connection portion 128. Therefore, the voltage resistance between the cathode 104 and the container 107 is reduced, and discharge is more likely to occur compared to the fourth embodiment. In other words, the curved portion 107d according to the fifth embodiment has a proximal point 107p, at which the distance from the cathode-side connection portion 122 to the inner circumferential surface of the container 107 is minimized. In the fifth embodiment, the distance Lcb between the proximal point 107p and the cathode-side connection portion 122 is less than the distance Lca between the anode-side connection portion 128 and the cathode-side connection portion 122.

[0076] Figure 4CThe sixth embodiment shown is a modification of the fifth embodiment. The difference between the sixth and fifth embodiments is that a protective member 120 with insulating properties is disposed between the bent portion 107d (proximal point 107p) and the cathode-side connection portion 122, so that the bent portion 107d (proximal point 107p) is not directly visible from the cathode-side connection portion 122. For example... Figure 4C and 4D As shown, the protective member 120 is a tubular member having a shape formed by rotating an L-shaped cross-section. The protective member 120 surrounds the X-ray tube 102 such that the bent portion 107d (proximal point 107p) is not directly visible from the area surrounding the cathode-side connection portion 122. The protective member 120 is made of an insulating solid material, such as ceramic, glass, or resin. The protective member 120 can have a 1×10⁻⁶ shape at 25°C. 5 Ωm or higher volume resistivity.

[0077] Next, refer to Figure 5A and 5B The method for determining the positions of the cathode-side connection portion 122 and the anode-side connection portion 128 will be described. Figure 5A and 5B This is a cross-sectional view showing the anode-side connection portion 128 and the cathode-side connection portion 122 of the X-ray tube 102 according to the seventh and eighth embodiments of the present invention.

[0078] In the seventh embodiment, both the anode member 2 and the cathode member 8, which are disc-shaped, are connected to the insulating tube 4 at their facing surfaces. In the seventh embodiment, the cathode-side connection portion 122 corresponds to the cathode-side end portion of the insulating tube 4, while the anode-side connection portion 128 corresponds to the anode-side end portion of the insulating tube 4. Therefore, the distance Lca between the cathode-side connection portion 122 and the anode-side connection portion 128 is the same as the length of the insulating tube 4 in the axial direction.

[0079] The eighth embodiment differs from the seventh embodiment in that the anode member 2 and the cathode member 8 include tubular sleeve portions that protrude in a direction such that the sleeve portions face each other. In the eighth embodiment, the cathode-side connecting portion 122 is offset from the cathode-side end of the insulating tube 4 along the axial direction Dt by the protruding length of the sleeve portion of the cathode member 8. Similarly, the anode-side connecting portion 128 is offset from the anode-side end of the insulating tube 4 along the axial direction Dt by the protruding length of the sleeve portion of the anode member 2. Therefore, the distance Lca between the cathode-side connecting portion 122 and the anode-side connecting portion 128 is less than the axial length of the insulating tube 4.

[0080] By using the above method, regardless of the shape of the anode member 2, the cathode member 8 and the insulating tube 4, the positions of the cathode-side connection portion 122 and the anode-side connection portion 128 can be determined in the region where the electric field is concentrated and adjacent to the opposite electrode.

[0081] Figure 6 This is a block diagram of an X-ray imaging system 200 according to a ninth embodiment of the present invention. The system controller 202 cooperates with each other to control the X-ray generating device 101 and the X-ray detection device 201.

[0082] The tube drive circuit 106 outputs various control signals to the X-ray tube 102 under the control of the system controller 202. The X-ray generating device 101 emits X-rays according to the control signals output from the system controller 202. The X-ray detector 206 detects the X-rays 11 emitted from the X-ray generating device 101 and passing through the object 204. The X-ray detector 206 includes multiple detection elements (not shown) and obtains the transmitted X-ray image. The X-ray detector 206 converts the transmitted X-ray image into an image signal and outputs the image signal to the signal processor 205. The signal processor 205 performs predetermined signal processing on the image signal under the control of the system controller 202 and outputs the processed image signal to the system controller 202. The system controller 202 outputs a display signal to the display device 203 according to the processed image signal, so that the display device 203 can display the image. The display device 203 displays the image (which is a captured image of the object 204) on the screen based on the display signal. A slit (not shown) with a predetermined gap, a collimator (not shown) with a predetermined opening, etc., can be disposed between the X-ray tube 102 and the object 204 to reduce unnecessary X-ray irradiation. In the ninth embodiment, the object 204 is supported by an arrangement portion or a delivery portion (not shown) to separate it from the X-ray tube 102 and the X-ray detector 206 by a predetermined distance.

[0083] The X-ray imaging system 200 according to the ninth embodiment can stably capture magnified images, the X-ray imaging system 200 including an X-ray generating device 101 suitable for magnified imaging and reducing discharge.

[0084] [Beneficial effects of the invention]

[0085] Using the present invention, it is possible to provide an X-ray generating device that has high reliability due to reduced discharge and can perform magnified imaging due to low SOD.

[0086] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims should be interpreted in the broadest sense to cover all modifications and equivalent structures and functions.

[0087] This application claims the benefit of Japanese Patent Application No. 2016-212124, filed on October 28, 2016, which is incorporated herein by reference in its entirety.

Claims

1. An X-ray generating apparatus comprising: an X-ray tube including: a cathode including an electron emission source, an anode including a transmission target, and an insulating tube joined to each of the anode and the cathode via an anode-side joining portion and a cathode-side joining portion, respectively, an insulating liquid; an electrically conductive container including a flange portion extending toward the insulating tube and a protruding portion protruding from the flange portion via a curved portion, the anode being fixed to the protruding portion, the container being configured to house the X-ray tube and the insulating liquid, a solid insulating member configured to be located between the curved portion and the cathode-side joining portion such that the curved portion cannot be directly seen from the cathode-side joining portion, wherein a distance between the curved portion and the cathode-side joining portion is smaller than a distance between the anode-side joining portion and the cathode-side joining portion.

2. The X-ray generating device of claim 1, wherein, the curved portion has a proximal point at which a distance from the cathode-side joining portion to an inner surface of the container is smallest.

3. The X-ray generating device of claim 1, wherein, the solid insulating member and the insulating liquid are located between the curved portion and the cathode-side joining portion.

4. The X-ray generating device of claim 1, wherein, The volume resistivity of the solid insulating member is greater than or equal to 1 x 10 5 Ωm.

Images