JP2011233363A - X-ray tube device and x-ray device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray tube device capable of deflecting an electron beam with excellent energy efficiency, moving a focus formed on a target surface, increasing X-ray output and suppressing the direct hit of a recoil electron to an X-ray radiation window, and an X-ray device provided with the X-ray tube device.SOLUTION: An X-ray tube device 10 comprises: an X-ray tube 30; and a deflection part 70. The X-ray tube 30 includes an anode target 35 having a target surface 35b, a cathode 36 for making an electron beam be incident on the target surface from a first direction d1 along a first plane S1 and forming a focus F on the target surface, and a vacuum envelope 31 having the X-ray radiation window 33 positioned in a second direction d2 along a second plane S2. The deflection part 70 deflects electron beam emitted from the cathode 36 in a direction along the first plane S1, and moves the position of the focus F on the target surface 35b along the first plane S1. An angle formed by the first direction d1 from the target surface 35b at a position where the focus F is formed is within the range of 8° to 40°.

Description

  The present invention relates to an X-ray tube device and an X-ray device including the X-ray tube device.

  The X-ray tube apparatus includes an X-ray tube. The X-ray tube is configured to generate an X-ray by colliding an electron beam with an anode target. Such an X-ray tube apparatus is used in many applications such as a medical diagnostic apparatus, an industrial nondestructive inspection apparatus, and a material analysis apparatus.

  During X-ray imaging, a technique is known in which the X-ray tube improves the resolution characteristics of an X-ray image by arranging X-ray focal points at a plurality of different positions with respect to the X-ray detector. In order to arrange the X-ray focal point at a plurality of positions, it is necessary to move the X-ray focal point instantaneously, and many techniques are known for that purpose (see, for example, Patent Documents 1 to 4).

  In the above X-ray tube apparatus, the electron beam is incident on the anode target from a direction substantially perpendicular to the moving direction of the focal point. However, in this case, since the supply voltage to the deflecting unit necessary for moving the focal point is generally large, it is necessary to deflect the electron beam with high energy efficiency, that is, with low energy. Therefore, as a method for efficiently deflecting an electron beam by an external magnetic field, a method is known in which a constriction is formed in a part of a vacuum envelope surrounding the electron beam and a magnetic deflection yoke is disposed in the constriction ( For example, see Patent Documents 5 to 8.)

  In the vacuum envelope, since the outer diameter of the constricted portion is small, the distance between the magnetic poles can be shortened. Since the magnetic flux density acting on the orbit of the electron beam can be increased, the energy required for deflecting the electron beam can be reduced, or the electron beam can be deflected even when the electron beam speed is high.

U.S. Pat. No. 4,010,370 U.S. Pat. No. 4,160,909 US Pat. No. 4,689,809 US Pat. No. 6,252,935 US Pat. No. 6,629,579 US Pat. No. 6,777,991 US Pat. No. 7,289,603 JP 2009-240577 A

  By the way, the potential of the X-ray emission window is the same as that of the anode target, or is substantially intermediate between the cathode potential and the anode potential. The recoil electrons that jump out in the direction of the X-ray emission window directly hit the X-ray emission window, so it is difficult to reduce the heating of the X-ray emission window. Due to the above, there is a problem that there is a limit in increasing the X-ray output.

  The present invention has been made in view of the above points, and an object of the present invention is to be able to deflect an electron beam in an energy efficient manner, move a focal point formed on a target surface, increase an X-ray output, and increase an X-ray emission window. An object of the present invention is to provide an X-ray tube apparatus and an X-ray apparatus including the X-ray tube apparatus that can suppress direct hit of recoil electrons.

In order to solve the above problems, an X-ray tube apparatus according to an aspect of the present invention provides:
An anode target having a target surface that emits X-rays upon incidence of an electron beam, and an electron beam from the first direction above the target surface along a first plane perpendicular to the target surface to the target surface. And a cathode forming a focal point on the target surface, the anode target and the cathode are accommodated, the inside is in a vacuum state, and along the second plane perpendicular to the target plane and the first plane from the focal point, respectively. A vacuum envelope having an X-ray radiation window located in the second direction, and an X-ray tube comprising:
A deflecting unit that deflects an electron beam emitted from the cathode in a direction along the first plane, and moves the position of the focal point on the target surface along the first plane;
An angle formed by the first direction from the target surface at a position where the focal point is formed is any one of a range of 8 ° to 40 °.

An X-ray apparatus according to another aspect of the present invention is
An anode target having a target surface that emits X-rays upon incidence of an electron beam, and an electron beam from the first direction above the target surface along a first plane perpendicular to the target surface to the target surface. And a cathode forming a focal point on the target surface, the anode target and the cathode are accommodated, the inside is in a vacuum state, and along the second plane perpendicular to the target plane and the first plane from the focal point, respectively. A vacuum envelope having an X-ray emission window positioned in the second direction, and deflecting an electron beam emitted from the cathode in a direction along the first plane, An X-ray tube apparatus comprising: a deflecting unit that moves a focal point on the target surface along the first plane;
A deflection power source for supplying a voltage to the deflection unit;
A deflection power source control unit that controls a voltage that the deflection power source supplies to the deflection unit so that the focal point moves continuously or intermittently on the target surface along the first plane;
An angle formed by the first direction from the target surface at a position where the focal point is formed is any one of a range of 8 ° to 40 °.

  According to the present invention, the electron beam can be deflected with high energy efficiency, the focal point formed on the target surface can be moved, the X-ray output can be increased, and the recoil electron direct hit to the X-ray radiation window can be suppressed. An X-ray apparatus including the X-ray tube apparatus and the X-ray tube apparatus can be provided.

It is a schematic diagram which shows the X-ray apparatus which concerns on the 1st Embodiment of this invention, and is the figure seen from the direction perpendicular | vertical to a target surface. It is the other schematic diagram which shows the X-ray apparatus shown in FIG. 1, and is the figure seen from the direction along the target surface. It is a perspective view which shows the anode target shown in FIG.1 and FIG.2, and is a figure which shows a mode that the position of a focus moves on a target surface by deflecting an electron beam. It is sectional drawing which shows the said anode target, and is a figure which shows a mode that an electron beam penetrate | invades inside an anode target and an X-ray is emitted from the inside of an anode target. It is sectional drawing which shows the anode target of the comparative example of the said X-ray apparatus, and is a figure which shows a mode that an electron beam penetrate | invades inside an anode target and an X-ray is emitted from the anode target inside. It is the figure which showed the change of the deflection angle of an electron beam with respect to the movement distance of a focus position in the X-ray apparatus of Example 1 which concerns on the said embodiment with the graph. It is the figure which showed the change of the deflection angle of the electron beam with respect to the movement distance of a focus position in the X-ray apparatus of Example 2 which concerns on the said embodiment with the graph. It is the figure which showed the change of the deflection angle of an electron beam with respect to the movement distance of a focus position in the X-ray apparatus of Example 3 which concerns on the said embodiment with the graph. It is the figure which showed the change of the deflection angle of an electron beam with respect to the movement distance of a focus position in the X-ray apparatus of Example 4 which concerns on the said embodiment with the graph. It is the figure which showed the change of the deflection angle of the electron beam with respect to the movement distance of a focus position in the X-ray apparatus of Example 5 which concerns on the said embodiment with the graph. It is the figure which showed the change of the deflection angle of an electron beam with respect to the movement distance of a focus position in the X-ray apparatus of Example 6 which concerns on the said embodiment with the graph. It is the figure which showed the change part of the distance between an electron emission source and a focus with respect to the movement distance of a focus position in the X-ray apparatus of Example 5 which concerns on the said embodiment. It is a perspective view which shows the said anode target, and is a figure which shows the shape of the track | orbit of an electron beam, and the focus formed in an anode target. It is sectional drawing which shows the X-ray tube apparatus of the X-ray apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows the X-ray tube apparatus along line XV-XV of FIG. It is sectional drawing which shows the X-ray tube apparatus along line XVI-XVI of FIG. It is sectional drawing which shows the X-ray tube apparatus of the X-ray apparatus which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows the X-ray tube apparatus along line XVIII-XVIII of FIG. It is sectional drawing which shows the X-ray tube apparatus along line XIX-XIX of FIG. It is sectional drawing which shows the X-ray tube apparatus of the X-ray apparatus which concerns on the 4th Embodiment of this invention. It is other sectional drawing which shows the X-ray tube apparatus shown in FIG. It is a front view which shows the X-ray tube apparatus shown in FIG.

Hereinafter, an X-ray apparatus according to a first embodiment of the present invention will be described in detail with reference to the drawings. In the first embodiment, a basic concept of an X-ray apparatus will be described.
As shown in FIGS. 1, 2, and 3, the X-ray apparatus includes an X-ray tube device 10, a deflection power source 81, a deflection power source control unit 82, a focusing power source 83, and a focusing power source control unit 84. I have. The X-ray tube device 10 includes an X-ray tube 30, a focal position detector 60, and a deflection unit 70.
The X-ray tube 30 includes an anode target 35, a cathode 36, a focusing electrode 9, and a vacuum envelope 31.

  The anode target 35 has a target surface 35b provided on a part of the outer surface of the anode target. The target surface 35b emits X-rays when an electron beam emitted from the cathode 36 is incident thereon. The anode target 35 is made of a metal such as a tungsten alloy. A positive voltage is applied to the anode target 35 relative to the cathode 36.

  The cathode 36 causes an electron beam to enter the target surface 35b from the first direction d1 along the first plane S1 perpendicular to the target surface 35b above the target surface 35b, thereby forming a focal point F on the target surface 35b. A negative voltage relative to the anode target 35 is applied to the cathode 36. A voltage and current applied to the cathode 36 are supplied to the electron emission source 36 a of the cathode 36. The electron emission source 36a is formed of an electrode, a coiled filament, or the like. Here, the electron emission source 36a is formed of a coiled filament.

  The focusing electrode 9 is located between the target surface 35 b and the cathode 36. The focusing electrode 9 is provided so as to surround the trajectory of the electron beam from the cathode 36 toward the focal point F. The focusing electrode 9 focuses the electron beam.

  The vacuum envelope 31 accommodates the anode target 35, the cathode 36 and the focusing electrode 9. The vacuum envelope 31 includes a vacuum vessel 32, an X-ray emission window 33, an X-ray transmission window 31a for detecting a focal position, and a metal surface portion 34. The inside of the vacuum envelope 31 is in a vacuum state. The vacuum container 32 is made of a metal such as copper, stainless steel, or aluminum.

  The X-ray emission window 33 is located in the second direction d2 along the second plane S2 perpendicular to the target surface 35b and the first plane S1 from the focal point F. The X-ray transmission window 31a is located in the third direction d3 different from the second direction d2 from the focal point F. The X-ray emission window 33 and the X-ray transmission window 31a are provided in the vacuum vessel 32 in an airtight manner. Here, the X-ray emission window 33 and the X-ray transmission window 31a are made of beryllium. The metal surface portion 34 is provided inside the vacuum envelope 31 including the surface of the X-ray radiation window 33 on the vacuum side and the surface of the X-ray transmission window 31a, and is set to the ground potential (0 V). In this embodiment, since the vacuum vessel 32, the X-ray emission window 33, and the X-ray transmission window 31a are made of metal, the entire vacuum envelope 31 is made of metal.

  Here, an angle formed by the first direction d1 from the target surface 35b where the focal point F is formed is α. An angle formed by the second direction d2 from the target surface 35b where the focal point F is formed is β.

  The angle α is in the range of 8 ° to 40 °. In this embodiment, the angle α is 12 °. The range of the angle β is not particularly limited, but the angle β is preferably in the range of 5 ° to 25 °.

  A high voltage power supply 15 is connected to the X-ray tube 30. The high voltage power supply 15 is for supplying a high voltage between the cathode 36 and the anode target 35. In this embodiment, the high voltage power supply 15 supplies a high voltage only to the cathode 36.

  A tube voltage V is applied between the cathode 36 and the anode target 35 of the X-ray tube 30. When the potential of the anode target 35 is VA and the potential of the cathode 36 is VC, the tube voltage V is VA-VC. The tube voltage V is 20 kV to 100 kV.

  In this embodiment, the high voltage power supply 15 supplies a voltage of −V to the cathode 36. The anode target 35 and the vacuum envelope 31 are grounded (0 V).

  The potential of the cathode 36 is not limited to −V, and may be set to any value within the range of −V to 0V (−V ≦ VC ≦ 0). The potential of the anode target 35 is not limited to the ground potential, and may be set to any value within the range of the ground potential to + V (0 ≦ VA ≦ + V).

  In particular, the potential of the cathode 36 is set to be in the range of −V to −V / 2 (−V ≦ VC ≦ −V / 2), and the potential of the anode target 35 is equal to or higher than the ground potential and equal to or lower than + V / 2. When it is set to any one of the ranges (0 ≦ VA ≦ + V / 2), it is possible to suppress recoil electrons directly hitting the X-ray emission window 33 and the X-ray transmission window 31a.

  In the X-ray tube 30 configured as described above, for example, a negative high voltage of −100 kV or more is applied to the cathode 36. The anode target 35 and the vacuum envelope 31 are grounded. The electron emission source 36a of the cathode 36 is further given a low voltage and current of ± 100 V or less.

  As a result, an electron beam is emitted from the cathode 36 to the target surface 35b of the anode target 35, X-rays are emitted from the focal point F formed on the target surface 35b, and the X-rays are transmitted through the X-ray emission window 33 to the outside. To be emitted.

  The focal position detector 60 is located outside the vacuum envelope 31 in the third direction d3 from the focal point F. The focus position detector 60 detects the position of the focus F formed on the target surface 35b when X-rays are incident from the target surface 35b, and outputs position information of the focus F.

  The focal position detector 60 includes an X-ray selective transmission unit 61 and an X-ray detector 62. The X-ray selective transmission unit 61 is formed by an X-ray shielding member having a slit or a slit collimator in which a plurality of X-ray shielding plates are arranged at intervals to form a plurality of slits. An X-ray shielding plate having a slit as an X-ray shielding member is disclosed, for example, in US Pat. No. 6,252,935. A slit collimator is disclosed in, for example, Japanese Patent Application Laid-Open No. 2009-240577. The X-ray detector 62 detects the position of the focal point F by detecting the position where the X-rays transmitted through the slit of the X-ray selective transmission unit 61 are incident, and outputs position information of the focal point F.

  The deflecting unit 70 deflects the electron beam emitted from the cathode 36 in the direction along the first plane S1, and moves the position of the focal point F on the target surface 35b along the first plane S1. In this embodiment, the deflection unit 70 is a magnetic deflection unit, and is provided outside the vacuum vessel 32 and at a position surrounding the trajectory of the electron beam.

  The deflection power supply 81 supplies a voltage to the deflection unit 70. The deflection power supply control unit 82 controls the voltage that the deflection power supply 81 supplies to the deflection unit 70 so that the focal point F moves continuously or intermittently on the target surface 35b along the first plane S1.

  The focusing power supply 83 supplies a voltage to the focusing electrode 9. The focus power supply controller 84 receives position information of the focus F from the focus position detector 60. The focusing power supply controller 84 controls the voltage supplied to the focusing electrode 9 by the focusing power supply 83 based on the position information of the focal point F. As a result, the size of the focal point F does not change depending on the position of the focal point F, and the focal point is not blurred or distorted, so that X-rays with uniform intensity can be emitted, contributing to the acquisition of a better X-ray image. can do.

  FIG. 4 is a diagram showing a state in which an electron beam is incident on the anode target 35 and X-rays are emitted from the anode target 35 in the above embodiment, and the first plane S1 and the second plane S2 are made into one plane. FIG.

  FIG. 5 is a cross-sectional view showing an anode target of an X-ray apparatus of a comparative example of this embodiment, and is a view showing a comparative example of FIG. FIG. 5 is a diagram illustrating a state in which an electron beam is incident perpendicularly to the target surface 35b and X-rays are emitted from the anode target 35, and is a diagram illustrating the second plane S2.

  As shown in FIG. 4, the angle α is in the range of 8 ° to 40 °. Let the penetration depth of the electron beam into the anode target 35 be d. The depth d is a specific length. Then, the maximum distance through which X-rays pass through the anode target 35 is d × sin α / sin β. As the value of d × sin α / sin β is smaller, that is, as the angle α is closer to 0 °, the absorption of X-rays generated in the anode target 35 by the anode target 35 can be suppressed. This is one of the reasons that the X-ray dose emitted from the anode target 35 increases. Further, the recoil electrons generated inside the anode target 35 have more components that pass through the surface side of the anode target 35 than in the prior art. The generation of X-rays in the anode target 35 occurs not only in the process in which the initial electron beam loses energy in the anode target 35, but also a recoil generated by elastic scattering of a part of the electron beam with almost no energy loss. It occurs even in the process of losing energy. X-rays generated inside the anode target 35 due to the recoil electrons are generated more on the surface side of the anode target 35 than in the prior art, and are thus easily emitted from the anode target 35. This is considered to be another factor that increases the X-ray dose than before.

  As in the example of FIG. 4, when the angle α is in the range of 8 ° to 40 °, the value of d × sin α / sin β can be reduced, so that the X-ray dose emitted from the anode target 35 is increased. Can be made.

  On the other hand, the larger the value of d × sin α / sin β, that is, the closer the angle α is to 90 °, the greater the amount of X-ray absorption by the anode target 35 and the lower the X-ray dose emitted from the anode target 35. Will do. Further, since recoil electrons generated in the anode target 35 have more components passing through a deeper portion of the anode target 35 than in the case of FIG. 4, X-rays generated in the anode target 35 due to the recoil electrons are not generated. It is more absorbed by the anode target 35 than the case of FIG. This is considered to be another factor that decreases the X-ray dose.

  As shown in FIG. 5, for this reason, when an electron beam is incident from a direction perpendicular to the target surface 35b, the distance through which the X-rays pass through the anode target 35 is d × sin 90 ° / sin β = d / sin β. In this case, since the value of d × sin α / sin β cannot be reduced, the X-ray dose emitted from the anode target 35 decreases.

  Next, the X-ray apparatus according to the first to sixth embodiments will be described as an example of an X-ray apparatus capable of deflecting an electron beam with high energy efficiency. In order to evaluate the energy efficiency of the X-ray apparatuses of Examples 1 to 6, the X-ray apparatus of the comparative example will be described.

First, an X-ray apparatus of a comparative example will be described.
As shown in FIGS. 3 and 6 to 11, when the angle α is 90 ° (α = 90 °), the deflection angle θ of the electron beam needs to be relatively large in order to move the position of the focal point F. . For this reason, the deflection power supply 81 needs to supply a relatively high voltage to the deflection unit 70. From the above, it has been impossible to realize an X-ray apparatus capable of deflecting an electron beam with high energy efficiency.

Next, the X-ray apparatus of Examples 1 to 6 will be described.
As shown in FIGS. 3 and 6 to 11, when the angle α is 40 °, 35 °, 30 °, 25 °, 20 °, and 15 °, compared to the case where the angle α is 90 ° (comparative example), It can be seen that the deflection angle θ of the electron beam for moving the focal point F by the same distance can be reduced.

  For this reason, in Examples 1 to 6, it can be seen that the voltage supplied to the deflecting unit 70 by the deflection power supply 81 can be reduced as compared with the comparative example. From the above, the X-ray apparatuses of Examples 1 to 6 can deflect an electron beam with energy efficiency. Note that the above-described effect can be obtained if the angle α of the X-ray apparatus is any one in the range of 8 ° to 40 °.

Next, the effect of providing the focus position detector 60 and the focusing power source controller 84 in the X-ray apparatus of this embodiment will be described.
As shown in FIGS. 2, 3 and 12, the X-ray apparatus of the comparative example (α = 90 °) is compared with the distance between the electron emission source 36a and the focus F even if the position of the focus F is moved. It can be seen that there is no change. In contrast, in the X-ray apparatus of this embodiment, for example, in the X-ray apparatus of Example 5 (α = 20 °), when the position of the focal point F is moved, the distance between the electron emission source 36a and the focal point F is increased. It turns out that a change becomes larger than a comparative example.

  For this reason, in the X-ray apparatus of this embodiment (8 ° ≦ α ≦ 40 °) such as the X-ray device of Example 5, when the position of the focal point F is moved, the size of the focal point F changes or the focal point F changes. It can be seen that blurring and distortion tend to occur.

  Therefore, in this embodiment, the X-ray apparatus is provided with the focus position detector 60 and the focusing power source controller 84. The focus position detector 60 can output the position information of the focus F, and the focusing power supply controller 84 supplies the focusing power supply 83 to the focusing electrode 9 based on the position information of the focus F input from the focus position detector 60. Since the voltage to be controlled can be controlled, the change in the size of the focus F based on the change in the position of the focus F, and the occurrence of blur and distortion in the focus F can be reduced.

  According to the X-ray apparatus according to the first embodiment configured as described above, the X-ray tube 30 includes the anode target 35, the cathode 36, and the vacuum envelope 31. The cathode 36 is set to a negative high potential, and the anode target 35 is grounded together with the vacuum envelope 31 including the X-ray emission window 33.

  The second plane S2 is perpendicular to the target surface 35b and the first plane S1. The X-ray radiation window 33 is located far from the first plane S1. Recoil electrons are emitted from the focal point F with an angular distribution such that incident electrons increase in the direction of specular reflection at the anode target 35b along the first plane S1. However, since the X-ray emission window 33 is not located on the first plane S1, direct hit of recoil electrons to the X-ray emission window 33 can be suppressed, and heating of the X-ray emission window 33 can be suppressed. Can do. And damage to the X-ray radiation window 33 can be prevented. Note that most of the recoil electrons that jump out of the focal point F impact the inner surface of the vacuum vessel 32 that is out of the X-ray emission window 33.

  The angle α is in the range of 8 ° to 40 °. Since the focal point F is formed by making the electron beam incident on the target surface 35b at a relatively shallow angle, the X-ray output emitted from the X-ray emission window 33 can be increased.

  Further, since scattering of recoil electrons above the target surface 35b can be reduced, recoil electrons colliding with the X-ray transmission window 31a and recoil electrons recollising with the target surface 35b including the vicinity of the focal point F can be prevented. Can be suppressed. Thereby, the heating of the X-ray transmission window 31a, the temperature rise of the target surface 35b (focal point F), and the roughness caused by the target surface 35b can be suppressed, and the generation of discharge and the decrease in the output of X-rays can be suppressed. . Furthermore, since the emission of X-rays from other than the focal point F can be suppressed, it is possible to suppress a decrease in the clarity of the X-ray image.

  From the above, it is possible to suppress recoil electrons from directly hitting the X-ray emission window 33 and the X-ray transmission window 31a, and without causing an excessive temperature rise of the X-ray emission window 33 and the X-ray transmission window 31a. An X-ray apparatus capable of increasing the X-ray output can be obtained.

  The deflection power supply control unit 82 can control the voltage supplied from the deflection power supply 81 to the deflection unit 70 so that the focal point F moves continuously or intermittently. The deflecting unit 70 is supplied with a controlled voltage to deflect the electron beam emitted from the cathode 36 in the direction along the first plane S1, and the position of the focal point F is the target along the first plane S1. It can be moved on the surface 35b. In other words, the deflecting unit 70 can scan the electron beam on the target surface 35b continuously or intermittently.

  In addition, when the X-ray apparatus of this embodiment is mounted on a CT apparatus, scanning can be performed while switching the focal position, so that it can be applied to a flying focus (focal position shift) type CT apparatus.

  Furthermore, when the X-ray apparatus of this embodiment is a fixed anode type X-ray apparatus, the weight and size can be reduced as compared with the rotary anode type X-ray apparatus. When a fixed anode type X-ray apparatus is mounted on a CT apparatus, the CT gantry can be rotated at a higher speed, and the imaging time can be further shortened. In addition, since the time required for capturing one tomographic image can be shortened, an X-ray image having less motion blur, that is, motion artifact can be obtained even when the subject is in a non-stationary object state.

  Furthermore, since the electron beam is scanned on the target surface 35b at a sufficiently high speed by the deflecting unit 70, an increase in the focus F temperature can be reduced. Therefore, even when a fixed anode type X-ray apparatus cannot be used practically because the target melts when the electron beam is not scanned, it can be used.

  Further, when the angle α is in the range of 8 ° to 40 ° as in the above embodiment, the position of the focus F is moved Δx when the angle α is 90 °. Compared with the method of moving the position by Δx, the deflection angle θ can be reduced, and the energy for deflecting the electron beam can be reduced.

  The vacuum envelope 31 positioned between the electron beam trajectory and the deflection unit 70 is formed in a cylindrical shape having a size that can secure the electron beam trajectory, and does not have a constricted portion.

  Since the vacuum envelope 31 does not have a constricted portion, the cathode 36 is not disposed further away from the anode target 35, and the potential distribution is not changed and the electron beam is not easily focused. Since the change in the size of the focus F and the occurrence of blur and distortion at the focus F can be reduced, it is possible to contribute to the acquisition of a better X-ray image.

  As described above, the electron beam can be deflected in an energy efficient manner, the focal point F formed on the target surface 35b can be moved, the X-ray output can be increased, and the recoil electron direct hit to the X-ray emission window 33 is suppressed. An X-ray tube device 10 and an X-ray device including the X-ray tube device 10 can be obtained.

  Next, the case where the electron emission source 36a is formed of a rectangular flat cathode having a long axis or a coiled filament will be described. Here, the case where the electron emission source 36a is formed of a coiled filament will be described as an example.

As shown in FIGS. 1 and 13, the cathode 36 emits an electron beam whose cross section perpendicular to the trajectory of the electron beam from the cathode 36 (electron emission source 36a) toward the focal point F is rectangular. This cross section has a major axis. The focal point F is formed in a rectangular shape, specifically a rectangular shape. The focal point F has a major axis along the second plane S2 and a minor axis along the first plane S1. For this reason,
The shape of the focal point F when viewed from the second direction d2 along the second plane S2 is smaller and becomes a shape closer to a square. That is, a higher X-ray intensity can be obtained while the apparent focal shape (effective focal point) is small.

  Next explained is an X-ray apparatus according to the second embodiment of the invention. In this embodiment, the X-ray tube is a rotary anode type X-ray tube. Hereinafter, a rotary anode type X-ray apparatus including a rotary anode type X-ray tube will be described. In this embodiment, the same reference numerals are given to the same functional portions as those in the first embodiment, and detailed description thereof will be omitted.

  As shown in FIGS. 14 to 16, the X-ray apparatus includes an X-ray tube apparatus 10. Although not shown, the X-ray apparatus also includes the deflection power source 81, the deflection power source control unit 82, the focusing power source 83, and the focusing power source control unit 84 described above. The X-ray tube apparatus 10 includes a rectangular box-shaped housing 20, an X-ray tube 30 accommodated in the housing 20, and a coolant 7 filled in the housing 20 and filling between the X-ray tube 30 and the housing 20. And a stator coil 910 as a rotational drive device, a focal position detector 60, and a deflection unit 70.

  The housing 20 has two divided parts 20a and 20c which are divided. The division part 20a has a frame part 20b on the outer edge side of the opening end. The division part 20c has a frame part 20d on the outer edge side of the opening end. The frame portion 20d is formed with a frame-like groove portion formed on the side facing the frame portion 20b.

The division parts 20a and 20c are brought into contact with each other so that the frame parts 20b and 20d face each other, and are fastened by a fastener (not shown). The gap between the frame part 20b and the frame part 20d is liquid-tightly sealed by a frame-shaped O-ring provided in the groove part. The O-ring has a function of preventing the coolant 7 from leaking outside the housing 20.
The housing 20 is provided with a rubber bellows 21 to adjust the pressure of the coolant 7. The housing 20 has a radiation window 24 that emits X-rays to the outside of the housing 20.

  The X-ray tube 30 includes a vacuum envelope 31. The vacuum envelope 31 includes a vacuum container 32 made of metal, an insulating member 40, and an insulating member 50. In this embodiment, the insulating member 50 is formed of a high voltage insulating member. An anode target 35 is indirectly attached to the insulating member 40, and a cathode 36 is indirectly attached to the insulating member 50. The cathode 36 emits an electron beam to the anode target 35. The anode target 35 and the cathode 36 are housed in a vacuum envelope 31.

  The inside of the vacuum envelope 31 is in a vacuum state. The X-ray radiation window 33 is provided in the vacuum container 32 in an airtight manner. Here, the X-ray emission window 33 is made of beryllium. The metal surface portion 34 is provided inside the vacuum vessel 32 including the surface side of the X-ray radiation window 33 on the vacuum side, and is set to the ground potential. The vacuum vessel 32 at a location facing the cathode 36, the focusing electrode 9 and the accelerating electrode 8 is formed in a cylindrical shape.

  The anode target 35 is formed in a disc shape. The anode target 35 has a target layer 35a provided on a part of the outer surface of the anode target. The target layer 35a emits X-rays when an electron beam emitted from the cathode 36 collides with it. The target layer 35a is formed of a metal such as molybdenum, a molybdenum alloy, or a tungsten alloy. The anode target 35 can rotate around the rotation axis A (tube axis). In this embodiment, the anode target 35 is set to the ground potential.

  A cathode support member 37 is connected to the cathode 36. The voltage supply terminal 54 is connected to the cathode 36 through the inside of the cathode support member 37. The voltage supply terminal 54 applies a negative high voltage to the cathode 36 and supplies voltage and current to the electron emission source 36 a of the cathode 36.

  The focusing electrode 9 is located between the focal point F and the cathode 36 inside the vacuum vessel 32. The focusing electrode 9 focuses the electron beam. The focusing electrode 9 is provided so as to surround the trajectory of the electron beam from the cathode 36 toward the focal point F. The focusing electrode 9 is attached to the cathode support member 37, for example. The adjusted negative high voltage is supplied to the focusing electrode 9.

  The acceleration electrode 8 is located between the focal point F and the focusing electrode 9 inside the vacuum vessel 32. The acceleration electrode 8 surrounds the trajectory of the electron beam from the cathode 36 toward the focal point F, and accelerates the electron beam to enter the target surface 35b. The acceleration electrode 8 is attached to the vacuum vessel 32, and the potential of the acceleration electrode 8 is fixed to the same potential (ground potential) as the vacuum vessel 32 and the anode target 35.

  The X-ray tube 30 includes a rotor 920, a bearing 930, a fixed body 1, and a rotating body 2. The fixed body 1 is formed in a cylindrical shape and is fixed to the insulating member 40. The fixed body 1 supports the rotating body 2 in a rotatable manner. The rotating body 2 is formed in a cylindrical shape and is provided coaxially with the fixed body 1. A rotor 920 is attached to the outer surface of the rotating body 2. The rotating body 2 and the anode target 35 are joined via a joint portion 35c. The rotating body 2 is provided so as to be rotatable together with the anode target 35.

  The insulating member 40 forms a part of the vacuum envelope 31. The insulating member 40 is formed by a cylindrical portion 46 and a bottom portion 47 that closes one end side of the cylindrical portion 46. The other end of the cylindrical portion 46 is airtightly joined to the vacuum vessel 32.

  The support member 26 is formed in an annular shape and is hermetically connected to the vacuum vessel 32. The support member 26 is bonded to the insulating member 50. The support member 26 faces the divided portion 20a (housing 20). The support member 26 has an annular groove formed on the side facing the dividing portion 20a. A gap between the support member 26 and the divided portion 20a is sealed by an annular O-ring provided in the groove portion. The O-ring has a function of preventing leakage of the coolant 7 from the gap between the support member 26 and the divided portion 20a to the outside.

  The insulating member 50 is hermetically attached to the support member 26 and forms a part of the vacuum envelope 31. The insulating member 50 has an external end surface 50 </ b> S exposed to the outside of the housing 20. In this embodiment, the outer end surface 50S is a flat surface.

  Inside the insulating member 50, a voltage supply terminal 54 connected to the cathode 36 and led out to the external end face 50S side is provided. In this embodiment, the voltage supply terminal 54 is a high voltage supply terminal. The voltage supply terminal 54 is provided so as to penetrate the external end face 50 </ b> S and supplies a high voltage to the cathode 36.

  The cable 102 is fixed by an insulating member 20 e provided at the opening of the housing 20. The cable 102 is electrically connected to the fixed body 1. The cable 102 sets the anode target 35 to the ground potential via the fixed body 1 and the like, and sets the vacuum vessel 32 (vacuum envelope 31) and the like to the ground potential.

  The high-voltage connector 200 includes a bottomed cylindrical housing 201, a cable 202 having a tip inserted into the housing 201, and the housing 201 filled with the terminal of the cable 202 facing the opening of the housing 201. A fixing portion 203 made of an epoxy resin material to be fixed and a silicone plate 204 made of a silicone resin material inserted between the fixing portion 203 and the outer end surface 50S of the insulating member 50 are provided. In this embodiment, cable 202 is a high voltage cable. The fixing part 203 is an electrical insulating material.

  In this embodiment, the fixing portion 203 as an electrical insulating material of the high voltage connector 200 is in intimate contact with the outer end surface 50 </ b> S of the insulating member 50. Note that the fixing portion 203 may be in direct contact with the outer end surface 50S. The high voltage connector 200 applies a high voltage to the voltage supply terminal 54.

  The X-ray tube apparatus 10 configured as described above is used as follows. When attaching the high voltage connector 200 to the housing 20, the silicone plates 204 are pressed so as to be in close contact with the fixing portion 203 and the outer end surface 50 </ b> S of the insulating member 50.

  An X-ray shielding cap 400 as an X-ray shielding part is detachably attached to the housing 20 so as to cover the high voltage connector 200. The X-ray shielding cap 400 is made of a material containing an X-ray opaque material.

  The coolant 7 is filled in the housing 20 and fills the space between the X-ray tube 30 and the housing 20. As the coolant 7, insulating oil or an aqueous coolant can be used. In this embodiment, an aqueous coolant is used as the coolant 7.

  The focal position detector 60 is located outside the housing 20 in the third direction d3 from the focal point F. Here, the focal position detector 60 is attached to the outer surface of the housing 20. The focus position detector 60 detects the position of the focus F formed on the target surface 35b when X-rays are incident from the target surface 35b, and outputs position information of the focus F.

  The focal position detector 60 includes an X-ray selective transmission unit 61 and an X-ray detector 62. The X-ray selective transmission part 61 is formed of an X-ray shielding member having a slit. The X-ray detector 62 detects the position of the focal point F by detecting the position where the X-rays transmitted through the slit of the X-ray selective transmission unit 61 are incident, and outputs position information of the focal point F.

  The deflection unit 70 is accommodated in the housing 20. The deflecting unit 70 is a magnetic deflecting unit, and is provided outside the vacuum vessel 32 at a position surrounding the electron beam trajectory. Here, the deflection unit 70 is disposed to face the focusing electrode 9. Needless to say, the constricted portion is not formed in the vacuum container 32 (vacuum envelope 31) at the location facing the deflecting portion 70.

  The deflecting unit 70 deflects the electron beam emitted from the cathode 36 in the direction along the first plane S1, and moves the position of the focal point F on the target surface 35b along the first plane S1.

  A cooling mechanism (not shown) is provided outside the housing 20. The cooling mechanism is connected to the inlet 20 i and the outlet 20 o of the housing 20. The cooling mechanism includes a coolant circulation pump that creates a flow of the coolant 7 in the housing 20 and a heat exchanger that releases the heat of the coolant 7 to the outside. For this reason, the coolant 7 is introduced into the housing 20 through the introduction port 20 i and is discharged out of the housing 20 through the discharge port 20 o.

  In the X-ray tube apparatus 10 configured as described above, by applying a predetermined current to the stator coil 910, the rotor 920 rotates and the anode target 35 rotates. Next, a predetermined high voltage is applied to the high voltage connector 200.

  The fixed body 1, the bearing 930, the rotating body 2, the joint portion 35c, and the anode target 35 are set to the ground potential via the cable 102. The high voltage applied to the high voltage connector 200 is applied to the cathode 36 via the voltage supply terminal 54. The vacuum envelope 31 including the X-ray radiation window 33 is grounded. The potential of the cathode 36 is set to -V. The potential of the anode target 35 is set to the ground potential.

  As a result, an electron beam is emitted from the cathode 36 to the target surface 35b of the anode target 35, X-rays are emitted from the focal point F formed on the target surface 35b, and the X-rays pass through the X-ray emission window 33 and the emission window 24. It is transmitted through and radiated to the outside. Since the X-ray tube apparatus 10 includes the deflection unit 70, X-rays can be emitted from the focal point F that has moved on the target surface 35b.

Next, the X-ray tube apparatus 10 shown in FIGS. 14 to 16 will be described with reference to FIG.
The cathode 36 makes an electron beam incident on the target surface 35b from the first direction d1, and forms a focal point F on the target surface 35b. The cathode 36 emits an electron beam having a rectangular cross section perpendicular to the trajectory of the electron beam from the cathode 36 toward the focal point F. The focal point F has a long axis parallel to the direction along the second plane S2, and is formed in a rectangular shape.

  The anode target 35 and the rotation axis A of the rotating body 2 are located on the opposite side of the X-ray emission window 33 with respect to the focal point F. The long axis of the focal point F is parallel to the second plane S2. In other words, the long axis of the focal point F is substantially orthogonal to the rotation direction of the anode target 35 around the rotation axis A.

  The X-ray radiation window 33 is located along the second direction d2 from the focal point F. The second plane S2 is perpendicular to the target surface 35b and the first plane S1. The angle α formed by the first direction d1 from the target surface 35b at the position where the focal point F is formed is in the range of 8 ° to 40 °. The angle β formed by the second direction d2 from the target surface 35b at the position where the focal point F is formed is in the range of 5 ° to 25 °.

  According to the X-ray apparatus according to the second embodiment configured as described above, the X-ray tube 30 includes the anode target 35, the cathode 36, and the vacuum envelope 31. The cathode 36 is set to a negative high potential, and the vacuum envelope 31 including the anode target 35 and the X-ray emission window 33 is grounded.

  The second plane S2 is perpendicular to the target surface 35b and the first plane S1. The X-ray radiation window 33 is located far from the first plane S1. Recoil electrons are emitted from the focal point F with an angular distribution such that incident electrons increase in the direction of specular reflection at the anode target 35b along the first plane S1. However, since the X-ray emission window 33 is not located on the first plane S1, direct hit of recoil electrons to the X-ray emission window 33 can be suppressed, and heating of the X-ray emission window 33 can be suppressed. Can do. And damage to the X-ray radiation window 33 can be prevented. Note that most of the recoil electrons that jump out of the focal point F impact the inner surface of the vacuum vessel 32 that is out of the X-ray emission window 33.

  The angle α is in the range of 8 ° to 40 °. Since the focal point F is formed by making the electron beam incident on the target surface 35b at a relatively shallow angle, the X-ray output emitted from the X-ray emission window 33 can be increased.

  Further, since scattering of recoil electrons above the target surface 35b can be reduced, recoil electrons colliding with the X-ray transmission window 31a and recoil electrons recollising with the target surface 35b including the vicinity of the focal point F can be prevented. Can be suppressed. Thereby, the heating of the X-ray transmission window 31a, the temperature rise of the target surface 35b (focal point F), and the roughness caused by the target surface 35b can be suppressed, and the generation of discharge and the decrease in the output of X-rays can be suppressed. . Furthermore, since the emission of X-rays from other than the focal point F can be suppressed, it is possible to suppress a decrease in the clarity of the X-ray image.

  From the above, it is possible to suppress recoil electrons from directly hitting the X-ray emission window 33 and the X-ray transmission window 31a, and without causing an excessive temperature rise of the X-ray emission window 33 and the X-ray transmission window 31a. An X-ray apparatus capable of increasing the X-ray output can be obtained.

  The deflection power supply control unit 82 can control the voltage supplied from the deflection power supply 81 to the deflection unit 70 so that the focal point F moves continuously or intermittently. The deflecting unit 70 is supplied with a controlled voltage to deflect the electron beam emitted from the cathode 36 in the direction along the first plane S1, and the position of the focal point F is the target along the first plane S1. It can be moved on the surface 35b. In other words, the deflecting unit 70 can scan the electron beam on the target surface 35b continuously or intermittently.

  Further, when the angle α is in the range of 8 ° to 40 ° as in the above embodiment, the position of the focus F is moved Δx when the angle α is 90 °. Compared with the method of moving the position by Δx, the deflection angle θ can be reduced, and the energy for deflecting the electron beam can be reduced.

  The vacuum envelope 31 positioned between the electron beam trajectory and the deflection unit 70 is formed in a cylindrical shape having a size that can secure the electron beam trajectory, and does not have a constricted portion.

  Since the vacuum envelope 31 does not have a constricted portion, the cathode 36 is not disposed further away from the anode target 35, and the potential distribution is not changed and the electron beam is not easily focused. Since the change in the size of the focus F and the occurrence of blur and distortion at the focus F can be reduced, it is possible to contribute to the acquisition of a better X-ray image.

  As the coolant 7, an aqueous coolant having the highest heat transfer coefficient and containing water as a main component can be used. For this reason, the coolant 7 can most effectively remove the heat transmitted to the vacuum vessel 32, the insulating member 40, the insulating member 50, and the support member 26. Further, since the water-based coolant has a larger specific heat than the insulating oil (about twice that of the insulating oil), the temperature rise of the coolant due to the heat radiation of the X-ray tube 30 is suppressed to a low level.

  Since the insulating member 40 is in contact with the coolant 7, the heat from the anode target 35 can be effectively dissipated into the coolant 7. Since the support member 26 is in contact with the cooling liquid 7, the heat transmitted from the cathode 36 to the insulating member 50 can be effectively dissipated to the cooling liquid 7, the temperature of the high voltage connector 200 connected to the insulating member 50 can be lowered, and long-term Insulation of the high voltage connector 200 can be ensured. The inner surface of the vacuum container 32 is heated by most of the recoil electrons that jump out of the focal point F or receives heat radiation from the anode target 35 that has become hot, but the outer surface of the vacuum container 32 has the coolant 7. Therefore, these heats can be effectively dissipated into the coolant 7.

  As described above, the electron beam can be deflected in an energy efficient manner, the focal point F formed on the target surface 35b can be moved, and the X-ray output can be increased without excessive temperature rise of the X-ray emission window 33. An X-ray tube apparatus 10 that can suppress direct hit of recoil electrons to the X-ray emission window 33 and an X-ray apparatus including the X-ray tube apparatus 10 can be obtained. Moreover, the X-ray tube apparatus 10 can be improved, and the X-ray apparatus including the X-ray tube apparatus 10 can be obtained with high reliability over a long period of time.

  Next explained is an X-ray apparatus according to the third embodiment of the invention. In this embodiment, the X-ray tube is a rotary anode type X-ray tube. Hereinafter, a rotary anode type X-ray apparatus including a rotary anode type X-ray tube will be described. In this embodiment, the same reference numerals are given to the same functional parts as those in the first and second embodiments, and the detailed description thereof is omitted.

  As shown in FIGS. 17 to 19, the X-ray apparatus includes an X-ray tube apparatus 10. Although not shown, the X-ray apparatus also includes the deflection power source 81, the deflection power source control unit 82, the focusing power source 83, and the focusing power source control unit 84 described above. The X-ray tube device 10 includes a housing 20, an X-ray tube 30 accommodated in the housing 20, a coolant 7 filled in the housing 20 and filling the space between the X-ray tube 30 and the housing 20, and a rotary drive device. The stator coil 910, the focal position detector 60, and the deflection unit 70 are provided.

  The housing 20 has a housing body 20f and an annular portion 20g. The housing body 20f is formed integrally with a cylindrical portion and an annular portion provided at one end of the cylindrical portion. A radiation window 24 for emitting X-rays to the outside is formed in a part of the cylindrical portion of the housing body 20f. The annular portion 20g is attached to the other end of the cylindrical portion (housing main body 20f). Here, the annular portion 20g is screwed (not shown) so as to be detachable from the cylindrical portion (housing main body 20f) using, for example, a screw as a fastener. An X-ray transmission window 20h for focus position detection is formed in a part of the annular portion 20g. The housing 20 is provided with a rubber bellows 21 to adjust the pressure of the coolant 7.

  The X-ray tube 30 includes a vacuum envelope 31. The vacuum envelope 31 includes a vacuum container 32 and insulating members 40 and 50. In this embodiment, the insulating members 40 and 50 are formed of a high voltage insulating member. An anode target 35 is indirectly attached to the insulating member 40, and a cathode 36 is indirectly attached to the insulating member 50. The cathode 36 emits an electron beam to the anode target 35. The anode target 35 and the cathode 36 are housed in a vacuum envelope 31.

  The inside of the vacuum envelope 31 is in a vacuum state. The X-ray radiation window 33 is provided in the vacuum container 32 in an airtight manner. The metal surface portion 34 is provided inside the vacuum vessel 32 including the surface side of the X-ray radiation window 33 on the vacuum side, and is set to the ground potential. The vacuum vessel 32 at a location facing the cathode 36, the focusing electrode 9 and the accelerating electrode 8 is generally cylindrical.

  The anode target 35 is formed in an annular shape. The anode target 35 has a target layer 35a. The anode target 35 can rotate around the rotation axis A (tube axis). In this embodiment, a positive high voltage is applied to the anode target 35.

  A cathode support member 37 is connected to the cathode 36. The voltage supply terminal 54 is connected to the cathode 36 through the inside of the cathode support member 37. The voltage supply terminal 54 applies a negative high voltage to the cathode 36 and supplies voltage and current to the electron emission source 36 a of the cathode 36.

  The focusing electrode 9 is located between the focal point F and the cathode 36 inside the vacuum vessel 32. The focusing electrode 9 focuses the electron beam. The focusing electrode 9 is provided so as to surround the trajectory of the electron beam from the cathode 36 toward the focal point F. The focusing electrode 9 is attached to the cathode support member 37, for example. The adjusted negative high voltage is supplied to the focusing electrode 9.

  The acceleration electrode 8 is located between the focal point F and the focusing electrode 9 inside the vacuum vessel 32. The acceleration electrode 8 surrounds the trajectory of the electron beam from the cathode 36 toward the focal point F, and accelerates the electron beam to enter the target surface 35b. The acceleration electrode 8 is attached to the fixed body 1, and the potential of the acceleration electrode 8 is fixed to the same potential as that of the anode target 35.

  The X-ray tube 30 includes a rotor 920, a bearing 930, a fixed body 1, and a rotating body 2. The fixed body 1 is formed in a columnar shape and is fixed to the insulating member 40. The fixed body 1 supports the rotating body 2 in a rotatable manner. The fixed body 1 is formed through the anode target 35. The rotating body 2 is formed in a cylindrical shape and is provided coaxially with the fixed body 1. A rotor 920 is attached to the outer surface of the rotating body 2. The rotating body 2 and the anode target 35 are joined via a joint portion 35c. The rotating body 2 is provided so as to be rotatable together with the anode target 35.

  The insulating member 40 forms a part of the vacuum envelope 31. The insulating member 40 is formed by a cylindrical portion 46 and a bottom portion 47 that closes one end side of the cylindrical portion 46. The other end of the cylindrical portion 46 is airtightly joined to the vacuum vessel 32.

  In this embodiment, the insulating member 40 is a high voltage insulating member. The insulating member 40 has an external end face 40 </ b> S exposed to the outside of the housing 20. In this embodiment, the outer end surface 40S is a flat surface.

  A voltage supply terminal 44 is provided on the external end face 40S. The voltage supply terminal 44 is connected to the fixed body 1. In this embodiment, the voltage supply terminal 44 is a high voltage supply terminal. The voltage supply terminal 44 supplies a positive high voltage to the anode target 35 via the fixed body 1 or the like.

  The support member 25 is formed in an annular shape and is bonded to the insulating member 40. The support member 25 faces the annular portion of the housing body 20f. The support member 25 has an annular groove formed on the side of the housing body 20f facing the annular portion. A gap between the support member 25 and the annular portion of the housing main body 20f is sealed by an annular O-ring provided in the groove portion. The O-ring has a function of preventing the coolant 7 from leaking to the outside through the gap between the annular portions of the support member 25 and the housing main body 20f.

  The support member 26 is formed in an annular shape and is hermetically connected to the vacuum vessel 32. The support member 26 is bonded to the insulating member 50. The support member 26 faces the annular portion 20g. The annular portion 20 g has an annular groove formed on the side facing the support member 26. A gap between the annular portion 20g and the support member 26 is sealed by an annular O-ring provided in the groove portion. The O-ring has a function of preventing leakage of the coolant 7 from the gap between the annular portion 20g and the support member 26 to the outside.

  The insulating member 50 is hermetically attached to the support member 26 and forms a part of the vacuum envelope 31. The insulating member 50 has an external end surface 50 </ b> S exposed to the outside of the housing 20. In this embodiment, the insulating member 50 is a high voltage insulating member, and the outer end surface 50S is a flat surface.

  Inside the insulating member 50, a voltage supply terminal 54 connected to the cathode 36 and led out to the external end face 50S side is provided. In this embodiment, the voltage supply terminal 54 is a high voltage supply terminal. The voltage supply terminal 54 is provided so as to penetrate the external end face 50 </ b> S and supplies a high voltage to the cathode 36.

  The high-voltage connector 100 includes a bottomed cylindrical housing 101, a cable 102 having a tip inserted into the housing 101, and the housing 101 filled with the terminal 102a of the cable 102 facing the opening side of the housing 101. And a fixed portion 103 made of an epoxy resin material and a silicone plate 104 made of a silicone resin material inserted between the fixed portion 103 and the outer end surface 40S of the bottom portion 47. In this embodiment, the cable 102 is a high voltage cable. The fixing part 103 is an electrical insulating material.

  In this embodiment, the fixing portion 103 as an electrical insulating material of the high voltage connector 100 is in intimate contact with the outer end surface 40S of the bottom portion 47. Note that the fixing portion 103 may be in direct contact with the outer end surface 40S. The high voltage connector 100 applies a positive high voltage to the voltage supply terminal 44.

  The X-ray tube apparatus 10 configured as described above is used as follows. When the high voltage connector 100 is attached to the housing 20, the silicone plate 104 is pressed so as to be in close contact with the fixing portion 103 and the outer end surface 40 </ b> S of the insulating member 40.

  The high voltage connector 200 includes a housing 201, a cable 202, a fixing portion 203, and a silicone plate 204. In this embodiment, cable 202 is a high voltage cable. The fixing part 203 is an electrical insulating material.

  In this embodiment, the fixing portion 203 as an electrical insulating material of the high voltage connector 200 is in intimate contact with the outer end surface 50 </ b> S of the insulating member 50. Note that the fixing portion 203 may be in direct contact with the outer end surface 50S. The high voltage connector 200 applies a high voltage to the voltage supply terminal 54.

  The X-ray tube apparatus 10 configured as described above is used as follows. When attaching the high voltage connector 200 to the housing 20, the silicone plates 204 are pressed so as to be in close contact with the fixing portion 203 and the outer end surface 50 </ b> S of the insulating member 50.

  An X-ray shielding cap 300 as an X-ray shielding part is detachably attached to the housing 20 so as to cover the high voltage connector 100. An X-ray shielding cap 400 as an X-ray shielding part is detachably attached to the housing 20 so as to cover the high voltage connector 200. The X-ray shielding cap 300 and the X-ray shielding cap 400 are made of a material containing an X-ray opaque material.

  When the anode target 35 is formed of molybdenum or a molybdenum alloy, the anode target 35 can shield X-rays. In this case, the X-ray tube apparatus 10 may not be provided with the X-ray shielding cap 300.

  The coolant 7 is filled in the housing 20 and fills the space between the X-ray tube 30 and the housing 20. As the coolant 7, insulating oil or an aqueous coolant can be used. In this embodiment, an aqueous coolant is used as the coolant 7.

  The focal position detector 60 is located outside the housing 20 in the third direction d3 from the focal point F. Here, the focal position detector 60 is attached to the outer surface of the housing 20. The focus position detector 60 detects the position of the focus F formed on the target surface 35b when X-rays are incident from the target surface 35b, and outputs position information of the focus F.

  The focal position detector 60 includes an X-ray selective transmission unit 61 and an X-ray detector 62. The X-ray selective transmission unit 61 is formed by a slit collimator. The X-ray detector 62 detects the position of the focal point F by detecting the position where the X-rays transmitted through the slit of the X-ray selective transmission unit 61 are incident, and outputs position information of the focal point F.

  The deflection unit 70 is accommodated in the housing 20. The deflecting unit 70 is a magnetic deflecting unit, and is provided outside the vacuum vessel 32 at a position surrounding the electron beam trajectory. Here, the deflection unit 70 is disposed to face the focusing electrode 9. Needless to say, the constricted portion is not formed in the vacuum container 32 (vacuum envelope 31) at the location facing the deflecting portion 70.

  The deflecting unit 70 deflects the electron beam emitted from the cathode 36 in the direction along the first plane S1, and moves the position of the focal point F on the target surface 35b along the first plane S1.

  A cooling mechanism (not shown) is provided outside the housing 20. The cooling mechanism is connected to the inlet 20 i and the outlet 20 o of the housing 20. The cooling mechanism has a coolant circulation pump and a heat exchanger.

  In the X-ray tube apparatus 10 configured as described above, by applying a predetermined current to the stator coil 910, the rotor 920 rotates and the anode target 35 rotates. Next, a predetermined high voltage is applied to each of the high voltage connectors 100 and 200.

  The high voltage applied to the high voltage connector 100 is applied to the anode target 35 and the acceleration electrode 8 through the voltage supply terminal 44, the fixed body 1, the bearing 930, the rotating body 2, and the joint portion 35c. The high voltage applied to the high voltage connector 200 is applied to the cathode 36 via the voltage supply terminal 54. The vacuum envelope 31 including the X-ray emission window 33 and the X-ray transmission window 31a is grounded. The potential of the cathode 36 is set to -V / 2. The potential of the anode target 35 is set to + V / 2.

  As a result, an electron beam is emitted from the cathode 36 to the target surface 35b of the anode target 35, X-rays are emitted from the focal point F formed on the target surface 35b, and the X-rays pass through the X-ray emission window 33 and the emission window 24. It is transmitted through and radiated to the outside. Since the X-ray tube apparatus 10 includes the deflection unit 70, X-rays can be emitted from the focal point F that has moved on the target surface 35b.

Next, the X-ray tube apparatus 10 shown in FIGS. 17 to 19 will be described with reference to FIG.
The cathode 36 makes an electron beam incident on the target surface 35b from the first direction d1, and forms a focal point F on the target surface 35b. The cathode 36 emits an electron beam having a rectangular cross section perpendicular to the trajectory of the electron beam from the cathode 36 toward the focal point F. The focal point F has a long axis parallel to the direction along the second plane S2, and is formed in a rectangular shape.

  The anode target 35 and the rotation axis A of the rotating body 2 are located on the first plane S1. The long axis of the focal point F is parallel to the second plane S2. In other words, the major axis of the focal point F is substantially parallel to the rotation direction of the anode target 35 around the rotation axis A.

  The X-ray radiation window 33 is located along the second direction d2 from the focal point F. The second plane S2 is perpendicular to the target surface 35b and the first plane S1. The angle α formed by the first direction d1 from the target surface 35b at the position where the focal point F is formed is in the range of 8 ° to 40 °. The angle β formed by the second direction d2 from the target surface 35b at the position where the focal point F is formed is in the range of 5 ° to 25 °.

  According to the X-ray apparatus according to the third embodiment configured as described above, the X-ray tube 30 includes the anode target 35, the cathode 36, and the vacuum envelope 31. The cathode 36 is set to a negative high potential, the anode target 35 is set to a positive high potential, and the vacuum envelope 31 including the X-ray emission window 33 is grounded.

  The second plane S2 is perpendicular to the target surface 35b and the first plane S1. The X-ray radiation window 33 is located far from the first plane S1. Recoil electrons are emitted from the focal point F with an angular distribution such that incident electrons increase in the direction of specular reflection at the anode target 35b along the first plane S1. However, since the X-ray emission window 33 is not located on the first plane S1, direct hit of recoil electrons to the X-ray emission window 33 can be suppressed, and heating of the X-ray emission window 33 can be suppressed. Can do. And damage to the X-ray radiation window 33 can be prevented. Note that most of the recoil electrons that jump out of the focal point F impact the inner surface of the vacuum vessel 32 that is out of the X-ray emission window 33.

  The angle α is in the range of 8 ° to 40 °. Since the focal point F is formed by making the electron beam incident on the target surface 35b at a relatively shallow angle, the X-ray output emitted from the X-ray emission window 33 can be increased.

  Further, since scattering of recoil electrons above the target surface 35b can be reduced, recoil electrons colliding with the X-ray transmission window 31a and recoil electrons recollising with the target surface 35b including the vicinity of the focal point F can be prevented. Can be suppressed. Thereby, the heating of the X-ray transmission window 31a, the temperature rise of the target surface 35b (focal point F), and the roughness caused by the target surface 35b can be suppressed, and the generation of discharge and the decrease in the output of X-rays can be suppressed. . Furthermore, since the emission of X-rays from other than the focal point F can be suppressed, it is possible to suppress a decrease in the clarity of the X-ray image.

  From the above, it is possible to suppress recoil electrons from directly hitting the X-ray emission window 33 and the X-ray transmission window 31a, and without causing an excessive temperature rise of the X-ray emission window 33 and the X-ray transmission window 31a. An X-ray apparatus capable of increasing the X-ray output can be obtained.

  The deflection power supply control unit 82 can control the voltage supplied from the deflection power supply 81 to the deflection unit 70 so that the focal point F moves continuously or intermittently. The deflecting unit 70 is supplied with a controlled voltage to deflect the electron beam emitted from the cathode 36 in the direction along the first plane S1, and the position of the focal point F is the target along the first plane S1. It can be moved on the surface 35b. In other words, the deflecting unit 70 can scan the electron beam on the target surface 35b continuously or intermittently.

  Further, when the angle α is in the range of 8 ° to 40 ° as in the above embodiment, the position of the focus F is moved Δx when the angle α is 90 °. Compared with the method of moving the position by Δx, the deflection angle θ can be reduced, and the energy for deflecting the electron beam can be reduced.

  The vacuum envelope 31 positioned between the electron beam trajectory and the deflection unit 70 is formed in a cylindrical shape having a size that can secure the electron beam trajectory, and does not have a constricted portion.

  Since the vacuum envelope 31 does not have a constricted portion, the cathode 36 is not disposed further away from the anode target 35, and the potential distribution is not changed and the electron beam is not easily focused. Since the change in the size of the focus F and the occurrence of blur and distortion at the focus F can be reduced, it is possible to contribute to the acquisition of a better X-ray image.

  As the coolant 7, an aqueous coolant having the highest heat transfer coefficient and containing water as a main component can be used. For this reason, the coolant 7 can most effectively remove the heat transmitted to the vacuum vessel 32, the insulating member 40, the insulating member 50, and the support member 26. Further, since the water-based coolant has a larger specific heat than the insulating oil (about twice that of the insulating oil), the temperature rise of the coolant due to the heat radiation of the X-ray tube 30 is suppressed to a low level.

  Since the insulating member 40 is in contact with the coolant 7, the heat from the anode target 35 can be effectively dissipated into the coolant 7. The insulating member 40 can lower the temperature of the high voltage connector 100 and can ensure the insulation of the high voltage connector 100 over a long period of time. Since the support member 26 is in contact with the cooling liquid 7, the heat transmitted from the cathode 36 to the insulating member 50 can be effectively dissipated to the cooling liquid 7, the temperature of the high voltage connector 200 connected to the insulating member 50 can be lowered, and long-term Insulation of the high voltage connector 200 can be ensured. The inner surface of the vacuum container 32 is heated by most of the recoil electrons that jump out of the focal point F or receives heat radiation from the anode target 35 that has become hot, but the outer surface of the vacuum container 32 has the coolant 7. Therefore, these heats can be effectively dissipated into the coolant 7.

  As described above, the electron beam can be deflected in an energy efficient manner, the focal point F formed on the target surface 35b can be moved, and the X-ray output can be increased without excessive temperature rise of the X-ray emission window 33. An X-ray tube apparatus 10 that can suppress direct hit of recoil electrons to the X-ray emission window 33 and an X-ray apparatus including the X-ray tube apparatus 10 can be obtained. Moreover, the X-ray tube apparatus 10 can be improved, and the X-ray apparatus including the X-ray tube apparatus 10 can be obtained with high reliability over a long period of time.

  Next explained is an X-ray apparatus according to the fourth embodiment of the invention. In this embodiment, the X-ray tube is a fixed anode type X-ray tube. Hereinafter, a fixed anode type X-ray apparatus including a fixed anode type X-ray tube will be described. In this embodiment, the same reference numerals are given to the same functional parts as those in the first to third embodiments, and the detailed description thereof is omitted.

  As shown in FIGS. 20 to 22, the X-ray apparatus includes an X-ray tube apparatus 10. Although not shown, the X-ray apparatus also includes the deflection power source 81, the deflection power source control unit 82, the focusing power source 83, and the focusing power source control unit 84 described above. The X-ray tube apparatus 10 includes an X-ray tube 30, a focus position detector 60, a deflecting unit 70, and a coolant cooler unit 90.

  The X-ray tube 30 includes a vacuum envelope 31. The vacuum envelope 31 includes a vacuum vessel 32, an insulating member 40, an insulating member 50, and an insulating member 80. In this embodiment, the insulating members 40, 50, 80 function as high voltage insulating members. An anode target 35 is attached to the insulating member 40, and the insulating member 40 forms a part of the vacuum envelope 31. The insulating member 40 is formed in a cylindrical shape. A cathode 36 is attached to the insulating member 50, and the insulating member 50 forms a part of the vacuum envelope 31. The insulating member 80 also forms part of the vacuum envelope 31.

  The anode target 35 is bonded to the insulating member 40. The anode target 35 has a housing portion 35d. The accommodating portion 35d is formed in a bowl shape having a narrow mouth near the insulating member 40 and bulging near the target surface 35b. The anode target 35, the cathode 36, the focusing electrode 9, and the acceleration electrode 8 are accommodated in the vacuum envelope 31. A voltage supply wiring that passes through the inside of the insulating member 80 is connected to the anode target 35. A positive high voltage is applied to the anode target 35 and the acceleration electrode 8. The vacuum vessel 32 at a location facing the cathode 36 and the focusing electrode 9 is formed in a cylindrical shape. A negative high voltage is applied to the cathode 36. The adjusted negative high voltage is supplied to the focusing electrode 9.

  The inside of the vacuum envelope 31 is in a vacuum state. The X-ray transmission window 31a for detecting the focal position is provided in the vacuum vessel 32 in an airtight manner. The metal surface portion 34 is provided inside the vacuum container 32 including the surface of the X-ray radiation window 33 on the vacuum side and the surface of the X-ray transmission window 31a, and is set to the ground potential.

  The X-ray tube 30 includes a tube portion 41, a ring portion 42, and a coolant 43. In this embodiment, the coolant 43 is an insulating oil. The tube portion 41 is made of a high voltage insulating material. The tube portion 41 is provided inside the insulating member 40 and the anode target 35. One end portion of the tube portion 41 extends to the outside of the vacuum envelope 31. The pipe part 41 forms an introduction path C1 into which the coolant 43 is introduced. The insulating member 40, the anode target 35, and the pipe part 41 form a discharge path C2 for discharging the coolant 43 therebetween.

  The ring part 42 is provided in the accommodating part 35d. The ring portion 42 is formed integrally with the tube portion 41 so as to surround the side surface of the end portion of the tube portion 41. The ring portion 42 is provided with a gap in the accommodating portion 35d.

  The anode target 35 has a passage C3 provided therein. The passage C3 is connected to the introduction passage C1 and the discharge passage C2. The coolant cooler unit 90 sends the coolant 43 to the introduction path C1, takes in the coolant 43 from the discharge path C2, and circulates the coolant 43. For this reason, the coolant 43 introduced from the introduction path C1 circulates through the passage C3 and is discharged from the discharge path C2.

The focal position detector 60 is located outside the vacuum envelope 31 in the third direction d3 from the focal point F. The focus position detector 60 detects the position of the focus F formed on the target surface 35b when X-rays are incident from the target surface 35b, and outputs position information of the focus F. The focal position detector 60 includes an X-ray selective transmission unit 61 and an X-ray detector 62. The X-ray selective transmission unit 61 is formed of an X-ray shielding member having a slit. The deflection unit 70 is a magnetic deflection unit, and is provided outside the vacuum vessel 32 at a position surrounding the electron beam trajectory. ing. Here, the deflection unit 70 is disposed to face the focusing electrode 9. Needless to say, the constricted portion is not formed in the vacuum container 32 (vacuum envelope 31) at the location facing the deflecting portion 70.

  The deflecting unit 70 deflects the electron beam emitted from the cathode 36 in the direction along the first plane S1, and moves the position of the focal point F on the target surface 35b along the first plane S1.

Next, the X-ray tube apparatus 10 shown in FIGS. 20 to 22 will be described with reference to FIG.
The cathode 36 makes an electron beam incident on the target surface 35b from the first direction d1, and forms a focal point F on the target surface 35b. The X-ray radiation window 33 is located along the second direction d2 from the focal point F. The second plane S2 is perpendicular to the target surface 35b and the first plane S1. The angle α formed by the first direction d1 from the target surface 35b at the position where the focal point F is formed is in the range of 8 ° to 40 °. The angle β formed by the second direction d2 from the target surface 35b at the position where the focal point F is formed is in the range of 5 ° to 25 °.

  According to the X-ray apparatus according to the fourth embodiment configured as described above, the X-ray tube 30 includes the anode target 35, the cathode 36, and the vacuum envelope 31. The cathode 36 is set to a negative high potential, the anode target 35 is set to a positive high potential, and the vacuum envelope 31 including the X-ray emission window 33 is grounded.

  The second plane S2 is perpendicular to the target surface 35b and the first plane S1. The X-ray radiation window 33 is located far from the first plane S1. Recoil electrons are emitted from the focal point F with an angular distribution such that incident electrons increase in the direction of specular reflection at the anode target 35b along the first plane S1. However, since the X-ray emission window 33 is not located on the first plane S1, direct hit of recoil electrons to the X-ray emission window 33 can be suppressed, and heating of the X-ray emission window 33 can be suppressed. Can do. And damage to the X-ray radiation window 33 can be prevented. Note that most of the recoil electrons that jump out of the focal point F impact the inner surface of the vacuum vessel 32 that is out of the X-ray emission window 33.

  The angle α is in the range of 8 ° to 40 °. Since the focal point F is formed by making the electron beam incident on the target surface 35b at a relatively shallow angle, the X-ray output emitted from the X-ray emission window 33 can be increased.

  Further, since scattering of recoil electrons above the target surface 35b can be reduced, recoil electrons colliding with the X-ray transmission window 31a and recoil electrons recollising with the target surface 35b including the vicinity of the focal point F can be prevented. Can be suppressed. Thereby, the heating of the X-ray transmission window 31a, the temperature rise of the target surface 35b (focal point F), and the roughness caused by the target surface 35b can be suppressed, and the generation of discharge and the decrease in the output of X-rays can be suppressed. . Furthermore, since the emission of X-rays from other than the focal point F can be suppressed, it is possible to suppress a decrease in the clarity of the X-ray image.

  From the above, it is possible to suppress recoil electrons from directly hitting the X-ray emission window 33 and the X-ray transmission window 31a, and without causing an excessive temperature rise of the X-ray emission window 33 and the X-ray transmission window 31a. An X-ray apparatus capable of increasing the X-ray output can be obtained.

  The deflection power supply control unit 82 can control the voltage supplied from the deflection power supply 81 to the deflection unit 70 so that the focal point F moves continuously or intermittently. The deflecting unit 70 is supplied with a controlled voltage to deflect the electron beam emitted from the cathode 36 in the direction along the first plane S1, and the position of the focal point F is the target along the first plane S1. It can be moved on the surface 35b. In other words, the deflecting unit 70 can scan the electron beam on the target surface 35b continuously or intermittently.

  Further, when the angle α is in the range of 8 ° to 40 ° as in the above embodiment, the position of the focus F is moved Δx when the angle α is 90 °. Compared with the method of moving the position by Δx, the deflection angle θ can be reduced, and the energy for deflecting the electron beam can be reduced.

  The vacuum envelope 31 positioned between the electron beam trajectory and the deflection unit 70 is formed in a cylindrical shape having a size that can secure the electron beam trajectory, and does not have a constricted portion. Since the vacuum envelope 31 does not have a constricted portion, the cathode 36 is not disposed further away from the anode target 35, and the potential distribution is not changed and the electron beam is not easily focused. Since the change in the size of the focus F and the occurrence of blur and distortion at the focus F can be reduced, it is possible to contribute to the acquisition of a better X-ray image.

  Furthermore, when the cathode has the same ground potential as that of the vacuum envelope 31, heating of the X-ray emission window 33 is suppressed, and therefore it is not necessary to cool the X-ray emission window 33 with the coolant. Further, in this case, recoil electrons do not impact the vacuum envelope 31 and most impact the side surface and back surface of the anode target 35 to heat the anode target 35, but the heat generated by the anode target 35 is the anode It is cooled by the coolant 43 that flows through the passage C3 provided inside the target 35. Since the X-ray tube 30 does not have to be installed in the housing together with the cooling liquid, the housing and the cooling liquid filling the housing can be made unnecessary. In that case, the X-ray tube apparatus 10 can be made more compact and lighter.

  In general, the fixed anode type X-ray tube apparatus 10 can reduce the weight and size as compared with the rotary anode type X-ray tube apparatus. When the X-ray tube apparatus 10 according to this embodiment is mounted on a CT apparatus, the CT gantry can be rotated at a higher speed than when a rotary anode type X-ray tube apparatus is mounted (conventional). It is possible to shorten the shooting time. Moreover, the X-ray tube apparatus 10 of this embodiment can also be mounted on a plurality of CT mounts. In this case, it is possible to shorten the shooting time without increasing the rotation speed of the gantry.

Furthermore, since the electron beam is scanned on the target surface 35b at a sufficiently high speed by the deflecting unit 70, an increase in the focus F temperature can be reduced.
The anode target 35 is heated by the impact of incident electrons and recoil electrons, but since this heat is transmitted to the coolant 43 flowing through the passage C3 provided in the anode target 35, it is radiated well.

  As described above, the electron beam can be deflected with high energy efficiency, the focal point F formed on the target surface 35b can be moved, the recoil electron direct hit to the X-ray emission window 33 can be suppressed, and the X-ray emission window 33 can be suppressed. The X-ray tube apparatus 10 and the X-ray apparatus equipped with the X-ray tube apparatus 10 can be obtained that can increase the X-ray output without excessive temperature rise.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

For example, the deflection unit 70 is not limited to a magnetic deflection unit, and may be an electrostatic deflection unit. When the deflection unit 70 is an electrostatic deflection unit, the deflection unit 70 is provided inside the vacuum vessel 32 so as to surround the trajectory of the electron beam, and the focal point F moves continuously or intermittently on the target surface 35b. The electron beam emitted from the cathode 36 can be deflected.
In the above embodiment, the anode target 35 is grounded together with the vacuum envelope 31 including the X-ray radiation window 33. However, the potential of the anode target 35 is not limited to the ground potential. It suffices if it is set within the range of the potential or a positive high potential.

  Furthermore, in the above embodiment, the case where the cathode 36 is set to a negative high potential has been described. However, the cathode 36 is not limited to a negative high potential, but may be a ground potential or a negative high potential. It may be set within the range.

  The present invention is not limited to the above X-ray tube device and X-ray device, but can be applied to various X-ray tube devices and X-ray devices.

  DESCRIPTION OF SYMBOLS 1 ... Fixed body, 2 ... Rotating body, 7 ... Coolant, 8 ... Accelerating electrode, 9 ... Focusing electrode, 10 ... X-ray tube apparatus, 20 ... Housing, 20h ... X-ray transmission window, 24 ... Radiation window, 30 ... X-ray tube, 31 ... Vacuum envelope, 31a ... X-ray transmission window, 32 ... Vacuum container, 33 ... X-ray emission window, 34 ... Metal surface portion, 35 ... Anode target, 35b ... Target surface, 36 ... Cathode, 36a ... Electron emission source, 40, 50 ... Insulating member, 40S, 50S ... External end face, 60 ... Focus position detector, 61 ... X-ray selective transmission part, 62 ... X-ray detector, 70 ... Deflection part, 81 ... Deflection Power supply, 82: Deflection power supply control unit, 83: Focusing power supply, 84: Focusing power supply control unit, 100, 200 ... High voltage connector, 300, 400 ... X-ray shielding cap, F ... Focus, d1 ... First direction, d2 ... 2nd direction, d3 ... 3rd direction, S1 ... 1st plane, S2 ... 2nd plane , Alpha, beta ... angle, theta ... deflection angle, A ... rotary shaft.

Claims (12)

An anode target having a target surface that emits X-rays upon incidence of an electron beam, and an electron beam from the first direction above the target surface along a first plane perpendicular to the target surface to the target surface. And a cathode forming a focal point on the target surface, the anode target and the cathode are accommodated, the inside is in a vacuum state, and along the second plane perpendicular to the target plane and the first plane from the focal point, respectively. A vacuum envelope having an X-ray radiation window located in the second direction, and an X-ray tube comprising:
A deflecting unit that deflects an electron beam emitted from the cathode in a direction along the first plane, and moves the position of the focal point on the target surface along the first plane;
The X-ray tube apparatus according to claim 1, wherein an angle formed by the first direction with respect to the target surface at a position where the focal point is formed is in a range of 8 ° to 40 °.   The X-ray tube according to claim 1, further comprising a focusing electrode located between the target surface and the cathode, surrounding a trajectory of the electron beam from the cathode toward the focal point, and focusing the electron beam. apparatus.   An acceleration electrode positioned between the focal point and the focusing electrode, surrounding an orbit of an electron beam from the cathode toward the focal point, and accelerating the electron beam to be incident on the target surface. 2. The X-ray tube apparatus according to 2.   The X-ray tube apparatus according to claim 3, wherein the acceleration electrode is set to the same potential as the anode target. The cathode emits an electron beam having a rectangular cross section perpendicular to the trajectory of the electron beam from the cathode toward the focal point,
The X-ray tube apparatus according to claim 1, wherein the focal point has a long axis along the second plane and is formed in a rectangular shape.   6. The angle according to claim 1, wherein an angle formed by the second direction from the target surface at a position where the focal point is formed is in a range of 5 ° to 25 °. The X-ray tube apparatus described. The anode target is fixed, is formed in a cylindrical shape extending along a rotation axis, and is rotatable around the rotation axis;
A fixed body that extends along the rotation axis and is provided inside the rotating body, and rotatably supports the rotating body;
A bearing provided between the fixed body and the rotating body,
The rotation axis is located on the opposite side of the X-ray emission window with respect to the focal point;
The X-ray tube apparatus according to claim 1, wherein a long axis of the focal point is parallel to the second plane. The anode target is fixed, is formed in a cylindrical shape extending along a rotation axis, and is rotatable around the rotation axis;
A fixed body that extends along the rotation axis and is provided inside the rotating body, and rotatably supports the rotating body;
A bearing provided between the fixed body and the rotating body,
The rotation axis is located on the first plane;
The X-ray tube apparatus according to claim 1, wherein a long axis of the focal point is parallel to the second plane.   The X-ray tube apparatus according to any one of claims 1 to 6, wherein the X-ray tube is a fixed anode X-ray tube.   Outside the vacuum envelope, located in a third direction different from the second direction from the focal point, X-rays are incident from the target surface, and the position of the focal point formed on the target surface is detected. The X-ray tube apparatus according to any one of claims 1 to 9, further comprising a focus position detector that outputs position information of the focus. An anode target having a target surface that emits X-rays upon incidence of an electron beam, and an electron beam from the first direction above the target surface along a first plane perpendicular to the target surface to the target surface. And a cathode forming a focal point on the target surface, the anode target and the cathode are accommodated, the inside is in a vacuum state, and along the second plane perpendicular to the target plane and the first plane from the focal point, respectively. A vacuum envelope having an X-ray emission window positioned in the second direction, and deflecting an electron beam emitted from the cathode in a direction along the first plane, An X-ray tube apparatus comprising: a deflecting unit that moves a focal point on the target surface along the first plane;
A deflection power source for supplying a voltage to the deflection unit;
A deflection power source control unit that controls a voltage that the deflection power source supplies to the deflection unit so that the focal point moves continuously or intermittently on the target surface along the first plane;
The X-ray apparatus according to claim 1, wherein an angle formed by the first direction from the target surface at a position where the focal point is formed is in a range of 8 ° to 40 °. A focusing power supply;
A focusing power supply control unit,
The X-ray tube device is located between the focal point and the cathode, surrounds the trajectory of the electron beam from the cathode toward the focal point, and focuses the electron beam, and outside the vacuum envelope, the focal point Is located in a third direction different from the second direction from which the X-ray is incident from the target surface, detects the position of the focal point formed on the target surface, and outputs the focal position information A detector, and
The focusing power supply supplies a voltage to the focusing electrode;
12. The X according to claim 11, wherein the focusing power supply controller controls a voltage supplied from the focusing power supply to the focusing electrode based on position information of the focus input from the focus position detector. Wire device.

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