Miniature microfocus x-ray tube and miniature microfocus x-ray tube system having the same

Abstract

The utility model discloses a kind of miniature microfocus ray tube and the miniature microfocus ray tube system with it, miniature microfocus ray tube includes: insulating component, the insulating component is defined with the vacuum cavity extending along its axial direction;Microfocus electron gun, it is arranged in the axial end of the insulating component to be connected with the insulating component sealing, the microfocus electron gun is used for emitting electron beam towards the other end of the insulating component axial direction, the axis of the electron beam and the axis of the vacuum cavity are mutually parallel or coincide;Anode window, it is arranged in the other end of the insulating component axial direction to be connected with the insulating component sealing, the anode window is provided with target material towards the side of the microfocus electron gun, the electron beam bombardment the target material to generate X-ray for transmission through the anode window. According to the utility model embodiment's miniature microfocus ray tube, since transmission target structure is used, the volume of ray tube can be significantly reduced, greatly reduce the weight of ray tube.

Description

Technical Field

[0001] This utility model belongs to the field of X-ray imaging technology, specifically relating to a miniature microfocus X-ray tube and a miniature microfocus X-ray tube system having the same. Background Technology

[0002] Current closed-loop microfocus X-ray tubes all employ a coaxial reflective target structure. The electron beam bombards the target, reflecting X-rays, with the electron beam axis perpendicular to the anode axis. Because the target and tube shell of a microfocus X-ray tube are coaxially aligned, the tube's insulation performance depends not only on the surface insulation performance of the insulating components (ceramic) but also on the vacuum insulation performance between the anode and the tube shell. Since the tube diameter is twice the insulation safety distance, this structure is not conducive to miniaturization. Furthermore, because the surface insulation length determines the anode rod length, this structure also hinders the lightweighting of microfocus X-ray tubes. Utility Model Content

[0003] The purpose of this utility model embodiment is to provide a miniature microfocus X-ray tube and a miniature microfocus X-ray tube system having the same, so as to solve the problem that miniature microfocus X-ray tubes are difficult to miniaturize and lighten in the prior art.

[0004] This utility model provides a miniature microfocus X-ray tube and a miniature microfocus X-ray tube system having the same.

[0005] The first aspect of this utility model provides a miniature microfocus X-ray tube.

[0006] The miniature microfocus X-ray tube according to an embodiment of the present invention includes: An insulating component defining a vacuum cavity extending along its axial direction; A microfocus electron gun is disposed at one end of the insulating component along its axial direction to be sealed to the insulating component. The microfocus electron gun is used to emit an electron beam toward the other end of the insulating component along its axial direction. The axis of the electron beam is parallel to or coincides with the axis of the vacuum cavity. An anode window is disposed at the other end of the insulating assembly along its axial direction to be sealed to the insulating assembly. A target is disposed on the side of the anode window facing the microfocus electron gun. The electron beam bombards the target to generate X-rays for transmission through the anode window.

[0007] Furthermore, the microfocus electron gun includes a cathode for emitting an electron beam toward the other end of the insulating assembly along its axial direction, the cathode being connected to a negative high voltage, and the anode window being grounded.

[0008] Furthermore, the end of the insulating component connected to the microfocus electron gun is provided with a ring-shaped shield in the circumferential direction.

[0009] Furthermore, the emission angle of the X-rays is greater than 170°.

[0010] Furthermore, the microfocus electron gun includes: A housing defining a mounting cavity, the housing being axially connected to one end of the insulating assembly; The cathode is located within the mounting cavity and is fixed to the housing via two thermal pins.

[0011] The miniature microfocus X-ray tube system according to a second aspect embodiment of the present invention includes: The miniature microfocus X-ray tube described in the above embodiments; A power supply assembly connected to the micro-microfocus X-ray tube to supply power to the micro-microfocus X-ray tube.

[0012] Furthermore, the microfocus electron gun includes: A housing defining a mounting cavity, the housing being axially connected to one end of an insulating assembly; The cathode is located within the mounting cavity and is fixed to the housing via two thermal pins. The power supply component includes: An accelerating power supply, which is a negative high-voltage power supply, is connected to the housing of the microfocus electron gun at its negative terminal, and the anode window is grounded.

[0013] Furthermore, the power supply assembly also includes: A cathode power supply is provided, with its positive terminal connected to the housing of the microfocus electron gun and its negative terminal connected to the cathode of the microfocus electron gun.

[0014] Furthermore, the microfocus electron gun also includes: A gate-controlled electrode, wherein the gate-controlled electrode is disposed within the mounting cavity; The power supply assembly also includes: A grid-controlled power supply is used to control the emission of an electron beam. The negative terminal of the grid-controlled power supply is connected to the grid-controlled electrode, and the positive terminal of the grid-controlled power supply is connected to the negative terminal of the cathode power supply.

[0015] Furthermore, the power supply assembly also includes: A cathode thermionic source, wherein the negative terminal of the cathode thermionic source is connected to the two thermionic pins of the cathode, and the positive terminal of the cathode thermionic source is connected to the negative terminal of the cathode power supply.

[0016] According to the embodiments of the present invention, the micro-focus X-ray tube, due to the use of a transmission target structure, can significantly reduce the volume of the X-ray tube and greatly reduce its weight. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a micro-focus X-ray tube in the prior art; Figure 2 This is a schematic diagram of the structure of the micro-focus X-ray tube according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the circuit principle of the micro-focus X-ray tube according to an embodiment of the present invention.

[0018] Attached Figure

[0019] Miniature microfocus X-ray tube 100; insulating component 10; microfocus electron gun 20; housing 21; cathode 22; thermal pin 23; grid-controlled electrode 24; anode window 30; target material 40; shielding component 50; electron beam 1; X-ray 2. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0021] The terms "first," "second," etc., used in the specification and claims of this utility model are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this utility model can be implemented in orders other than those illustrated or described herein. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0022] The following is combined Figures 1 to 3 The miniature microfocus X-ray tube 100 provided in this utility model embodiment will be described in detail through specific embodiments and application scenarios.

[0023] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0024] According to an embodiment of the present invention, a micro-focus ray tube 100 includes an insulating component 10, a micro-focus electron gun 20, and an anode window 30.

[0025] Specifically, the insulating component 10 defines a vacuum cavity extending along its axial direction; a microfocus electron gun 20 is disposed at one end of the insulating component 10 along its axial direction to be sealed and connected to the insulating component 10, and the microfocus electron gun 20 is used to emit an electron beam 1 toward the other end of the insulating component 10 along its axial direction, the axis of the electron beam 1 being parallel to or coincident with the axis of the vacuum cavity; an anode window 30 is disposed at the other end of the insulating component 10 along its axial direction to be sealed and connected to the insulating component 10, and a target material 40 is disposed on the side of the anode window 30 facing the microfocus electron gun 20, and the electron beam 1 bombards the target material 40 to generate X-rays 2 for transmission through the anode window 30.

[0026] In other words, such as Figure 2 As shown, the miniature microfocus X-ray tube 100 according to an embodiment of the present invention mainly includes a microfocus electron gun 20 and a transmission target structure. An electron beam 1 emitted from the microfocus electron gun 20 directly bombards the target material 40 on the anode window 30 and exits from the anode window 30. The axis of the electron beam 1 is coaxial with or coincides with the insulating component 10. In this structure, the insulation performance of the X-ray tube is mainly determined by the surface insulation performance of the insulating component 10 (ceramic). If increasing the voltage doubles the insulation safety distance, then the length of the insulating component 10 only needs to be doubled, which is very beneficial for miniaturization. Conversely, in the prior art, such as... Figure 1 As shown, the miniature microfocus X-ray tube A typically uses a reflective target B. If increasing the voltage doubles the insulation safety distance, the radial diameter of the corresponding insulation component C must double. This demonstrates that the existing structure is not conducive to miniaturization. In this invention, the diameter of the X-ray tube is no longer constrained by vacuum insulation performance; therefore, the diameter can be significantly reduced, and the weight of the insulation component 10 can be significantly reduced. Furthermore, since the transmission target structure does not require a copper anode rod, the overall weight of the miniature microfocus X-ray tube 100 can be greatly reduced.

[0027] Therefore, the micro-focus X-ray tube 100 according to the present invention, by adopting a transmission target structure, can significantly reduce the volume of the X-ray tube and greatly reduce its weight.

[0028] According to one embodiment of the present invention, the microfocus electron gun 20 includes a cathode for emitting an electron beam 1 toward the other end of the insulating assembly 10 in the axial direction, the cathode being connected to a negative high voltage, and an anode window 30 being grounded.

[0029] Specifically, traditional closed-tube reflective target microfocus X-ray sources use positive high-voltage drive. To avoid vacuum discharge, a safe distance needs to be maintained between the anode and the window. Therefore, the focal object distance (FOD) must be at least 5 mm. Furthermore, the higher the voltage level of the microfocus X-ray tube, the larger the FOD, which is less conducive to achieving a large imaging magnification ratio. According to the embodiment of this utility model, the microfocus X-ray tube 100 uses a negative high-voltage drive mode. Since the target is coated on the inner wall of the window, the FOD can be made very small, less than 2 mm, which is very beneficial for achieving a large imaging magnification ratio in a small space.

[0030] Preferably, an annular shield 50 is provided circumferentially at one end of the insulating component 10 connected to the microfocus electron gun 20, which can improve the external insulation performance.

[0031] Optionally, the emission angle of X-ray 2 is greater than 170°.

[0032] Specifically, by combining the transmissive micro-focus X-ray tube 100 with the negative high-voltage driving mode, the working emission angle of the micro-focus X-ray tube 100 is close to 180°, which is much larger than that of the closed-tube reflective target micro-focus X-ray source constrained by the tube shell, making it easier to image objects at close range.

[0033] According to one embodiment of the present invention, the microfocus electron gun 20 includes a housing and a cathode.

[0034] Specifically, the housing defines a mounting cavity, the housing is connected to one axial end of the insulating assembly 10, and the cathode is located in the mounting cavity and fixed to the housing by two thermal pins.

[0035] The micro-microfocus X-ray tube system according to a second aspect embodiment of the present invention includes the micro-microfocus X-ray tube 100 described in the above embodiment and a power supply component, wherein the power supply component (not shown) is connected to the micro-microfocus X-ray tube 100 to supply power to the micro-microfocus X-ray tube 100.

[0036] According to one embodiment of the present invention, the microfocus electron gun 20 includes a housing 21 and a cathode 22.

[0037] The housing 21 defines a mounting cavity, and the housing 21 is connected to one end of the insulating assembly 10 in the axial direction; the cathode 22 is located in the mounting cavity and is fixed to the housing 21 by two thermal pins 23; The power supply assembly includes an accelerating power supply, which is a negative high-voltage power supply. The negative terminal of the accelerating power supply is connected to the housing 21 of the microfocus electron gun 20, and the anode window 30 is grounded.

[0038] Specifically, such as Figure 3As shown, U0 is the accelerating power supply, which is a negative high-voltage power supply. The anode window 30 is grounded, and the outer shell of the microfocus electron gun 20 is connected to a negative potential with a voltage between -50 and -130kV, which is used to accelerate electrons to the required energy.

[0039] Furthermore, the power supply assembly also includes a cathode power supply, the positive terminal of which is connected to the housing 21 of the microfocus electron gun 20, and the negative terminal of which is connected to the cathode 22 of the microfocus electron gun 20.

[0040] Specifically, such as Figure 3 As shown, Uc is the cathode power supply, with the positive terminal connected to the outer shell of the microfocus electron gun 20 and the negative terminal connected to the cathode 22. The cathode power supply voltage and the accelerating power supply voltage are used together to focus the electron beam 1.

[0041] According to one embodiment of the present invention, the microfocus electron gun 20 further includes a gate control electrode 24 disposed within the mounting cavity; the power supply assembly further includes a gate control power supply, which is used to control the emission of the electron beam 1, the negative terminal of the gate control power supply being connected to the gate control electrode 24, and the positive terminal of the gate control power supply being connected to the negative terminal of the cathode power supply. Figure 3 In the diagram, Ug is the gate-controlled power supply, with its positive terminal connected to the negative terminal of Uc and its negative terminal connected to the gate-controlled electrode 24, used to control the emission current of the cathode 22.

[0042] Furthermore, the power supply assembly also includes a cathode thermal power supply, the negative terminal of which is connected to the two thermal pins 23 of the cathode 22, and the positive terminal of which is connected to the negative terminal of the cathode power supply.

[0043] Specifically, Uh is the cathode thermal power supply, which is connected to the two thermal pins 23 of the cathode 22. One end of the power supply is connected to the negative terminal of Uc, and is used to heat the cathode 22 to emit electrons.

[0044] Other structures and techniques of the micro-focus X-ray tube system according to the embodiments of this utility model are prior art and will not be described in detail here.

[0045] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. A miniature microfocus X-ray tube, characterized in that, include: An insulating component defining a vacuum cavity extending along its axial direction; A microfocus electron gun is disposed at one end of the insulating component along its axial direction to be sealed to the insulating component. The microfocus electron gun is used to emit an electron beam toward the other end of the insulating component along its axial direction. The axis of the electron beam is parallel to or coincides with the axis of the vacuum cavity. An anode window is disposed at the other end of the insulating assembly along its axial direction to be sealed to the insulating assembly. A target is disposed on the side of the anode window facing the microfocus electron gun. The electron beam bombards the target to generate X-rays for transmission through the anode window.

2. The micro-focus X-ray tube according to claim 1, characterized in that, The microfocus electron gun includes a cathode for emitting an electron beam toward the other end of the insulating assembly along its axial direction, the cathode being connected to a negative high voltage, and the anode window being grounded.

3. The micro-focus X-ray tube according to claim 1, characterized in that, The insulating component is provided with a ring-shaped shield at one end where it is connected to the microfocus electron gun.

4. The micro-focus X-ray tube according to claim 1, characterized in that, The X-ray emission angle is greater than 170°.

5. The micro-focus X-ray tube according to claim 1, characterized in that, The microfocus electron gun includes: A housing defining a mounting cavity, the housing being axially connected to one end of the insulating assembly; The cathode is located within the mounting cavity and is fixed to the housing via two thermal pins.

6. A miniature microfocus ray tube system, characterized in that, include: The micro-focus X-ray tube according to any one of claims 1-5; A power supply assembly connected to the micro-microfocus X-ray tube to supply power to the micro-microfocus X-ray tube.

7. The micro-focus X-ray tube system according to claim 6, characterized in that, The microfocus electron gun includes: A housing defining a mounting cavity, the housing being axially connected to one end of an insulating assembly; The cathode is located within the mounting cavity and is fixed to the housing via two thermal pins. The power supply component includes: An accelerating power supply, which is a negative high-voltage power supply, is connected to the housing of the microfocus electron gun at its negative terminal, and the anode window is grounded.

8. The micro-focus X-ray tube system according to claim 7, characterized in that, The power supply assembly also includes: A cathode power supply is provided, with its positive terminal connected to the housing of the microfocus electron gun and its negative terminal connected to the cathode of the microfocus electron gun.

9. The micro-focus X-ray tube system according to claim 8, characterized in that, The microfocus electron gun also includes: A gate-controlled electrode, wherein the gate-controlled electrode is disposed within the mounting cavity; The power supply assembly also includes: A grid-controlled power supply is used to control the emission of the electron beam. The negative terminal of the grid-controlled power supply is connected to the grid-controlled electrode, and the positive terminal of the grid-controlled power supply is connected to the negative terminal of the cathode power supply.

10. The micro-focus ray tube system according to claim 9, characterized in that, The power supply assembly also includes: A cathode thermionic source, wherein the negative terminal of the cathode thermionic source is connected to the two thermionic pins of the cathode, and the positive terminal of the cathode thermionic source is connected to the negative terminal of the cathode power supply.

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