阅读说明：本技术 X射线管绝缘体 (X-ray tube insulator ) 是由 R·K·O·贝林 T·施伦克 T·雷佩宁 于 2018-06-15 设计创作，主要内容包括：本发明提出了一种处于X射线管内的绝缘体,所述绝缘体具有真空侧和环境侧以及馈通,所述馈通基本上与所述真空侧的对称轴和所述环境侧的对称轴一致。所述真空侧的所述对称轴和所述环境侧的所述对称轴相对于彼此具有至少5°,优选90°的角度。还提出了一种包括这种绝缘体的X射线源,并且本发明还扩展到一种用于使用具有这种绝缘体的X射线源来生成患者的X射线图像的医学成像装置。在实施例中,提供了一种X射线源,其中,所述绝缘体在环境表面处被插入电连接器。(The invention proposes an insulator in an X-ray tube, having a vacuum side and an ambient side and a feed-through which substantially coincides with an axis of symmetry of the vacuum side and an axis of symmetry of the ambient side. The axis of symmetry of the vacuum side and the axis of symmetry of the ambient side have an angle of at least 5 °, preferably 90 °, with respect to each other. An X-ray source comprising such an insulator is also proposed, and the invention also extends to a medical imaging apparatus for generating an X-ray image of a patient using an X-ray source having such an insulator. In an embodiment, an X-ray source is provided, wherein the insulator is inserted with electrical connectors at the ambient surface.)

1. An asymmetric X-ray tube insulator (200) for providing isolation between a ground potential (208) and a potential (207) of a feedthrough, the insulator comprising:

a vacuum interface (201) for contacting a vacuum region (211) of an X-ray tube,

an environment interface (202) for being in contact with an environment (212) of the X-ray tube,

a feedthrough channel (213) inside the insulator for receiving the feedthrough to conduct a potential of the feedthrough from the environmental interface to the vacuum interface,

wherein the feedthrough channel extends from the vacuum interface to the environmental interface inside the insulator,

wherein the vacuum interface and the environmental interface are angled with respect to each other,

wherein a first axis perpendicular to the vacuum interface is at an angle of at least 5 °, preferably 90 °, to a second axis perpendicular to the environmental interface,

wherein the vacuum interface has a diameter, and wherein the environmental interface has a diameter, an

Wherein the diameter of the vacuum interface exceeds the diameter of the environmental interface by at least a factor of 2.

2. The asymmetric X-ray tube insulator of claim 1, further comprising:

a conductive outer surface (214) for carrying the ground potential, and

wherein the conductive outer surface extends from the vacuum interface to the environmental interface.

3. The asymmetric X-ray tube insulator according to claim 1 or 2,

wherein the vacuum interface and the environmental interface are angled with respect to each other characterized in that,

the feed-through channel (213) extending from the vacuum interface (201) in a first direction into the insulator (200),

wherein the feed-through channel (213) extends from the environmental interface (202) in a second direction into the insulator, and

wherein the first and second directions have an angle of at least 5 °, preferably 90 °, with respect to each other.

4. The asymmetric X-ray tube insulator of claim 3, wherein the first direction is parallel to the first axis, and wherein the second direction is parallel to the second axis.

5. The asymmetric X-ray tube insulator according to any one of the preceding claims,

wherein the first axis perpendicular to the vacuum interface (201) is a virtual symmetry axis (205) and the second axis perpendicular to the environmental interface (202) is a virtual symmetry axis (206).

6. The asymmetric X-ray tube insulator according to any one of the preceding claims,

wherein the insulator is formed of a homogeneous body of an isotropic material, preferably alumina.

7. The asymmetric X-ray tube insulator according to any one of the preceding claims,

wherein the vacuum interface has a virtual circular axis of symmetry,

wherein the vacuum interface is realized as a wafer-type insulator interface that is substantially flat and has a structured surface,

wherein the environmental interface has a virtual circular symmetry axis or has a virtual discrete rotational symmetry axis, and

wherein the two axes of symmetry are angled with respect to each other.

8. The asymmetric X-ray tube insulator according to any one of claims 1 to 6,

wherein the vacuum interface has a virtual circular axis of symmetry,

wherein the vacuum interface is realized as a substantially flat wafer-type insulator interface with a structured surface, wherein the thickness of the virtual circular symmetry axis is shorter than the diameter of the vacuum interface, and

wherein the insulator has a conical shape at the environmental interface.

9. The asymmetric X-ray tube insulator according to any one of claims 1 to 6,

wherein the insulator has a conical shape at the vacuum interface,

wherein the environmental interface has a virtual circular axis of symmetry,

wherein the environmental interface is realized as a wafer-type insulator interface that is substantially flat and has a structured surface.

10. Asymmetric X-ray tube insulator according to one of claims 7, 8 or 9,

wherein the axis of symmetry of the vacuum interface extends parallel to a direction in which the feed-through channel extends from the vacuum interface into the insulator,

wherein the axis of symmetry of the environmental interface extends parallel to a direction in which the feedthrough channel extends from the environmental interface into the insulator.

11. The asymmetric X-ray tube insulator according to any one of the preceding claims,

wherein the feed-through channel inside the insulator is curved and/or angled within the insulator.

12. The asymmetric X-ray tube insulator according to any one of claims 2 to 11,

wherein the conductive outer surface extends perpendicularly from the vacuum interface toward the angled section of the insulator, and

wherein the conductive outer surface extends perpendicularly from the environmental interface toward the angled section of the insulator.

13. The asymmetric X-ray tube insulator according to any one of claims 2 to 12,

wherein the conductive outer surface circumferentially surrounds the vacuum interface and

wherein the electrically conductive outer surface circumferentially surrounds the environmental interface.

14. An X-ray source (302) for generating X-rays, the source comprising an insulator (307) according to any one of claims 1 to 13,

wherein the insulator is in contact with a vacuum region of the X-ray source via the vacuum interface; and is

Wherein the insulator is in contact with an environment of the X-ray source via the environment interface.

15. A medical imaging apparatus (300) for generating an X-ray image of a patient, the medical imaging apparatus comprising:

x-ray source with an insulator (307) according to any one of claims 1 to 13.

Technical Field

In general, the invention relates to the field of X-ray sources and/or X-ray generators for generating X-ray radiation. In particular, the present invention relates to an asymmetric X-ray tube insulator, an X-ray source for generating X-rays and a medical imaging apparatus for generating an image of a patient.

Background

High voltage ceramic insulators for X-ray tubes isolate the high potential from ground potential and enable power supply through feedthroughs for e.g. control voltage, current, sensor signals, heat.

An axisymmetric design is preferred to simplify manufacturing and minimize thermal or electrical distortion. These insulators may be cylindrical, conical, or substantially flat, also referred to by the skilled artisan as "wafer" insulators. They are typically structured, for example, to shield the triple point and function even under adverse conditions on the vacuum side (e.g., the influence of dissociating agents such as charge carriers, UV or X-rays, etc.) and the environmental side under oil or flexible bulk insulators (rubber, silicone sheets, plastics, etc.).

High voltage ceramic insulators are typically the interface between the vacuum and the ambient oil, rubber, silicon or plastic insulation.

US 4811375a describes an X-ray tube comprising a generally cylindrical evacuated metal tube envelope having an anode rotatably mounted therein. Ceramic insulation is provided inside the tube envelope near the anode to prevent arcing. The anodes are rotated by an external variable speed DC drive motor that is magnetically coupled to the rotating anode assembly through the tube envelope wall. The tube enclosure wall includes ferrous sections that minimize gaps in magnetic coupling while allowing for a thick, robust tube enclosure wall. A variable speed DC motor or a variable speed pneumatic motor may be used to drive the anode. In a preferred embodiment, the anode drive unit is electromechanically fastened to the anode, whereby the drive unit can be brought to a desired anode speed and then fastened to the anode, which drive unit acts as a flywheel to bring the anode to speed quickly. An electromagnet serving as a clutch is also employed. In addition, the anode driving unit may be operated at a high speed suitable for radiography, and the electromagnetic clutch unit may be intermittently operated to maintain the anode rotation during fluoroscopy. When a radiographic phase is required in the middle of the fluoroscopy, the electromagnetic clutch is actuated to bring the anode to its full speed. An alternative drive unit comprises a DC stator outside the tube envelope that acts on an inner rotor mounted for rotation with the anode. The X-ray tube also includes a cathode rotatably mounted in the tube envelope and containing a plurality of cathode filaments. A cathode rotation drive unit is provided for rotating the cathode to select a desired filament. The cathode drive unit is preferably magnetically coupled through the tube wall to rotate the cathode. The DC drive motor includes a DC stator outside the tube envelope that operates on a rotor with encapsulated rare earth magnets, and an AC stator that operates on a squirrel cage rotor through laminated segmented tube walls. A fan is provided for air cooling of the tube envelope.

Disclosure of Invention

The inventors of the present invention have found that because the vacuum interface is typically weakest at the maximum allowable electric field strength, there may be a mismatch in the required dimensions between the two interfaces. The coaxial designs used in the prior art to date can become bulky.

Therefore, there may be a need for an improved way of isolating ground potential from the potential of the feed-through of the insulator used in the X-ray tube.

This is achieved by the subject matter of the independent claims, wherein further embodiments are incorporated in the dependent claims and in the following description.

According to a first aspect of the present invention, an asymmetric X-ray tube insulator for providing isolation between ground potential and the potential of a feedthrough is presented. The asymmetric X-ray tube insulator comprises: a vacuum interface for contact with a vacuum region of an X-ray tube, and an environmental interface for contact with an environment of the X-ray tube. Further, the insulator includes a feedthrough channel inside the insulator for receiving the feedthrough to direct the potential of the feedthrough from the environmental interface to the vacuum interface. Further, the feedthrough channel extends from the vacuum interface to the environmental interface inside the insulator. The vacuum interface and the ambient interface of the insulator are angled with respect to each other.

In other words, asymmetric X-ray tube insulators (hereinafter "insulators") have a vacuum interface and an ambient interface that are generally not parallel to each other. Instead, the interfaces extend perpendicular to the respective axes of symmetry, but the two axes of symmetry are not identical, but are angled with respect to each other. This will become apparent from several different embodiments and is explained below. This is in contrast to an axisymmetric prior art insulator, where both the vacuum interface and the ambient interface extend perpendicular to a parallel or same axis of symmetry, respectively. Thus, the asymmetric insulator of the present invention can be viewed as providing a non-coaxial design of the insulator to be used in an X-ray tube. The skilled person will understand that the angled configuration of the vacuum interface and the ambient interface relates to a main surface of the vacuum interface and a main surface of the ambient interface. For example, a technician considers the surface portion of the vacuum interface extending perpendicular to the direction in which the feedthrough extends through the vacuum interface when determining the angular configuration between the vacuum interface and the environmental interface. In the same way, in this exemplary example, the surface portion of the environmental interface extending perpendicular to the direction in which the feedthrough extends through or along the environmental surface is used to determine the angled configuration of the asymmetric insulator. This concept of an angled interface is illustrated and elucidated in the context of several different embodiments and can be clearly derived from the embodiment of fig. 2, for example.

In other words, the asymmetric shape of the insulator allows the feedthrough channel to extend from the environmental interface into the insulator in a first direction and the feedthrough channel to extend from the vacuum interface into the insulator in another direction, wherein the first and second directions are not parallel to each other. This geometrical aspect of the insulator will be explained and elucidated hereinafter in the context of several different embodiments.

The inventors of the present invention have found during their research on X-ray tubes that the horizontal width, i.e. the axial thickness, of the insulator should be reduced for future applications of the X-ray tube. Such a horizontal width of the insulator can be seen, for example, in fig. 2, where the horizontal width is given by the distance between the vacuum interface 201 and the long conductive outer surface on the right side of fig. 2 (extending in a direction from the top to the bottom of fig. 2), where both reference numerals 208 and 214 terminate. This horizontal width of the insulator is minimized due to the angled non-coaxial configuration, i.e., due to the asymmetric shape of the insulator 200. In general, the asymmetric insulator of the present invention (which includes a vacuum interface and an ambient interface that are angled with respect to each other) provides such a reduced horizontal width. This asymmetric shape significantly reduces the horizontal width of the insulator, thereby allowing the insulator to be used in future X-ray tubes that may limit this space. At the same time, the asymmetric shape of the insulator allows to take into account the different electrical conditions that the vacuum interface and the environmental interface have to satisfy. At the vacuum interface, problems may arise due to charge carriers, and discharge problems need to be taken into account. The asymmetric geometry of the insulator of the present invention allows for the provision of a large vacuum interface while enabling a significant reduction in the diameter of the ambient interface. This still matches the electrical requirements of both surfaces.

As will be apparent from the following description, the insulator of the present invention relates to a solid matter insulator, wherein different materials may be used. Different examples of material selection will be given below.

The insulator may comprise one feedthrough channel having a feedthrough extending therein, but may of course also comprise two, three, four or more feedthrough channels having corresponding feedthrough channels extending therein. In preferred embodiments, the insulator may provide two, four or six feed-through channels with respective feed-throughs.

Further, the insulator of the present invention is configured to isolate ground potential from the potential of one or more feedthroughs extending through the insulator. For medical imaging applications, for example, when using asymmetric X-ray tube insulators in the X-ray tube of a medical imaging device, typical voltages may range from 20kV to 150 kV.

However, the field of application of the insulator of the present invention is beyond the field of medical imaging. For example, in the field of non-destructive materials testing, the insulator of the present invention may be used. In this field, voltages up to 600kV may be applied, and the insulator of this embodiment is configured to provide corresponding isolation. Another field of application of the insulator of the invention is the field of diffractometers and the field of fluorescence analysis for analyzing compounds. In such a technical field only a voltage of 10kV may be applied, and the inventive insulator may of course also provide a corresponding isolation for such an application.

Therefore, according to an exemplary embodiment of the present invention, a medical imaging apparatus with an X-ray tube comprising an asymmetric X-ray tube insulator is proposed. In an alternative embodiment, an apparatus for non-destructive material testing is presented, the apparatus comprising an X-ray tube having the asymmetric X-ray tube insulator of the present invention. In another exemplary embodiment, a device for diffraction measurements or for fluorescence analysis is proposed, which has an X-ray tube and an asymmetric X-ray tube insulator.

As will be clear to the skilled person, when the insulator is applied to or mounted on the X-ray tube itself, the vacuum interface of the insulator is in contact with the vacuum region of the X-ray tube. Furthermore, in this mounting configuration, the environmental interface of the insulator is in contact with the environment of the X-ray tube.

By using different options, the feedthrough can be brought into contact with the feedthrough channel. According to an exemplary embodiment, during the manufacturing of the insulator, the insulator provides one or more feed-through channels as hollow channels within the insulator, in which hollow channels the conductive material of the feed-through is soldered. Thus, by soldering the electrical feedthrough into the feedthrough channel, it can be achieved that no air gap is enclosed between the conductive feedthrough and the solid matter surrounding the insulator. In an alternative production method, the feed-through is brought into contact with the insulator along the feed-through channel by using a powder sintering method. Typically, temperatures above 1900 ℃ are used during the sintering process. After sintering, the ceramic body is usually metallized in the region of the mechanical interface and brazed with a metal shield and a support structure.

According to another exemplary embodiment, the insulator comprises a conductive outer surface for carrying a ground potential, wherein the conductive outer surface extends from the vacuum interface to the environment interface.

The conductive outer surface may be implemented, for example, as a metal layer on the outer surface of the insulator. However, according to another exemplary embodiment, not the entire outer surface of the insulator is electrically conductive, but only a partial section of the outer surface is electrically conductive. According to another exemplary embodiment, a semiconducting outer surface is used.

According to another exemplary embodiment of the invention, the vacuum interface and the ambient interface of the insulator are angled with respect to each other in the following manner: such that the feedthrough channel extends from the vacuum interface into the insulator in a first direction and the feedthrough channel extends from the environment interface into the insulator in a second direction. In this embodiment, the first direction and the second direction have an angle of at least 5 °, preferably 90 °, with respect to each other.

As may be taken from the exemplary embodiment of fig. 2, for example, the two directions may be oriented perpendicularly with respect to each other. In the embodiment of fig. 2, the first and second directions are equal to two axes of symmetry 205, 206, since the embodiment of fig. 2 comprises an ambient interface 202 showing rotational symmetry with respect to the axis 207, whereas the vacuum interface 201 shows rotational symmetry with respect to the axis of symmetry 205. However, other angled configurations besides the perpendicular configuration are also embodiments that fall within the scope of the present invention.

According to another exemplary embodiment of the present invention, the diameter of the vacuum interface exceeds the diameter of the ambient interface by a factor of at least 2.

As can be taken from the embodiment shown in fig. 2, for example, the diameter of the environmental interface 202 is significantly smaller compared to the diameter of the vacuum interface 201. The diameters of the two interfaces are compared in the cross-sectional view shown in fig. 2.

According to another exemplary embodiment of the present invention, the insulator is formed by a homogeneous body of isotropic material. In a preferred embodiment, alumina is used.

Due to the use of isotropic material it is ensured that no electrical effects occur between different materials within the insulator, since by this embodiment boundary layers are avoided.

According to another preferred embodiment, the insulator is realized as a one-piece component.

In this embodiment it is also ensured that no air gaps are included between the different parts of the insulator, which would cause negative electrical effects within the insulator. In particular, such an insulator avoids any disadvantages of an unwanted discharge process. It is of course clear to the skilled person that the isotropic feature mentioned above relates only to the insulator itself, whereas the feed-through material will be different as it is considered non-insulating but carrying the feed-through voltage.

According to another exemplary embodiment of the invention, the asymmetric insulator comprises a vacuum interface with a circular symmetry axis, and the vacuum interface is realized as a wafer-type insulator interface, which is substantially flat and has a structured surface. Furthermore, in this embodiment, the environmental interface has a virtual circular axis of symmetry or has a virtual discrete axis of rotational symmetry, and the two axes of symmetry are at an angle to each other.

Such a structured surface can be taken from fig. 2, for example, wherein two recesses above and below the feedthrough 207 are comprised in the surface of the vacuum interface 201. However, due to their diameter to thickness ratio, the skilled person understands such interfaces as wafer-type insulator interfaces.

It must be noted that the term "wafer-type insulator interface" is commonly used and clearly understood by the skilled person. In particular, the skilled person understands a wafer-type insulator interface as an interface having a high ratio of the diameter of the interface divided by the depth of the interface. This wafer-type insulator interface is represented in fig. 2 by vacuum interface 201.

As is commonly used by those skilled in the art, the axial thickness of the wafer insulator/wafer insulator interface is generally shorter than its diameter, in addition to the conical insulator. The wafer insulation appears to be a substantially flat disc, at least on the ambient side. A disadvantage of this short design is the reduction of the leakage path, which is understood to be the path length from the high voltage terminal to ground across the insulator. Even under unfavorable conditions, such as free charge carriers in vacuum, high residual gas pressure, vacuum UV irradiation, impact of loose particles, etc., a suitable structuring of the surface and bulk material is essential to achieve the necessary high-pressure stability.

According to another exemplary embodiment of the present invention, the asymmetric X-ray tube insulator has a vacuum interface with an imaginary circular symmetry axis and the vacuum interface is realized as a wafer-type insulator interface which is substantially flat and has a structured surface.

In contrast to the previous embodiments, the insulator has a conical shape at the environmental interface, which generally simplifies achieving a sufficiently large leakage path. According to another exemplary embodiment of the present invention, the insulator has a conical shape at the vacuum interface and the ambient interface has an imaginary circular symmetry axis and is realized as a wafer-type insulator which is substantially flat and has a structured surface.

According to a further exemplary embodiment of the present invention, the axis of symmetry of the vacuum interface extends parallel to the direction in which the feed-through channel extends from the vacuum interface into the insulator. Furthermore, the symmetry axis of the environmental interface extends parallel to the direction in which the feed-through channel extends from the environmental interface into the insulator. Such an embodiment is shown in the non-limiting example of fig. 2, where both virtual symmetry axes of both interfaces are parallel to the direction away from both interfaces. According to a further exemplary embodiment of the present invention, the feed-through channel inside the insulator is curved and/or angled within the insulator.

Such curved and/or angled path features of the feed-through channel may of course be applied to several channels, which in embodiments comprising several feed-throughs are comprised by an insulator.

According to another exemplary embodiment of the invention, the conductive outer surface extends from the vacuum interface perpendicularly towards the angled section of the insulator. Further, the electrically conductive outer surface of the insulator extends perpendicularly from the environmental interface toward the angled section of the insulator.

As can be taken from fig. 2, the two ends of the insulator 200 extend perpendicularly away from the respective interfaces and then meet at an angled section of the outer surface of the insulator along the ground potential directed along the circumference of the insulator. For example, in the non-limiting embodiment of FIG. 2, the inner short mechanical connection between the two interfaces includes a vertical segment. This internal short mechanical connection is shown on the left side of fig. 2. In contrast, the longer mechanical connection between the two interfaces shown on the right hand side of fig. 2 comprises two angled sections, wherein each section is angled at 45 °. It will be clear to the skilled person in light of this disclosure that several different angles may also be used, based on the different geometries provided according to different embodiments of the invention.

According to another exemplary embodiment of the present invention, the electrically conductive outer surface circumferentially surrounds the vacuum interface and the ambient interface.

According to another aspect of the invention, an X-ray source for generating X-rays is proposed. The X-ray source comprises an insulator according to any of the embodiments or aspects mentioned herein. The insulator is in contact with a vacuum region of the X-ray source via a vacuum interface, and the insulator is in contact with an environment of the X-ray source via an environment interface.

Such X-ray sources may be applied in several different technical fields. Such an X-ray source may be applied, for example, in an X-ray imaging device for medical purposes, or in a non-destructive material testing device, or in a diffractometer or fluorescence analysis device.

In an embodiment, an X-ray source is provided, wherein an insulator is inserted into the electrical connector at the ambient surface.

According to another exemplary embodiment of the present invention, a medical imaging apparatus for generating X-ray images of a patient is presented, wherein the apparatus comprises an X-ray source with an insulator according to any of the embodiments and aspects mentioned herein.

These and other aspects of the invention are apparent from and will be elucidated with reference to the embodiments described hereinafter.

Drawings

The subject matter of the invention will be explained in more detail below with reference to exemplary embodiments shown in the drawings, in which

Fig. 1 shows a cross-sectional view through a prior art insulator commonly used in X-ray sources;

fig. 2 schematically shows a cross-section through an asymmetric insulator according to an exemplary embodiment of the present invention; and is

Fig. 3 schematically shows a medical imaging system comprising an X-ray source and an X-ray source insulator according to another exemplary embodiment of the present invention.

Detailed Description

Fig. 1 schematically shows a cross-section through an X-ray source comprising a prior art X-ray source insulator. An X-ray source 100 is shown having a vacuum region 101 with an alumina portion 102. In fig. 1, the vacuum interface is indicated by reference numeral 106. Furthermore, a silicon plate 103 is included, which is an electrically stable interface, wherein a small diameter is sufficient. Further, a plastic insulator 104 is included in the arrangement shown in fig. 1. The X-ray source 100 also includes an oil or cable interface 105, which is an interface with the environment. As can be seen from fig. 1, the prior art utilizes axisymmetric designs, since they simplify manufacturing and minimize thermal or electrical distortion. Until now, the skilled person has considered such axisymmetric and/or concentric X-ray insulators as being beneficial and sufficient, since they can successfully shield even under adverse conditions on the vacuum side (e.g. the influence of free agents like charge carriers, UV or X-rays, etc.) and on the environmental side under oil or flexible bulk insulators.

However, the inventors of the present invention have found during their research that different geometries of the insulator are beneficial for several different applications of the X-ray source in the future. In an embodiment, the inventors of the present invention propose the use of an angled isotropic insulator, such as an angled alumina ceramic insulator, which represents the interface between the vacuum and the environment. This may be applicable to X-ray tubes and other vacuum electronics.

As a non-limiting example, fig. 2 shows a cross-section of an asymmetric X-ray tube insulator 200 for providing isolation between ground potential 208 and a potential 207 of a feedthrough. The insulator comprises a vacuum interface 201 for contacting a vacuum region 211 of the X-ray tube. Furthermore, the environment interface 202 is configured for being in contact with an environment 212 of the X-ray tube. A feedthrough channel 213 extends inside the insulator and is configured for receiving a feedthrough to conduct a potential of the feedthrough from an environmental interface to a vacuum interface. Electrical connectors and cables may then be applied to one or more feedthroughs of the insulation on the vacuum side in order to bring power to several different devices, such as control devices, sensors or heating devices. As can be seen from fig. 2, the feed-through channel 213 extends inside the insulator 200 from the vacuum interface 201 to the environment interface 202. The vacuum interface 201 and the ambient interface 202 are angled with respect to each other. Thus, a non-coaxial and non-axisymmetric design and geometry is provided. The insulator 200 of this embodiment is extremely flat along the axis of symmetry 205 of the vacuum interface 201, taking into account the mismatch in the required dimensions between the two interfaces. In other words, the horizontal width (i.e., axial thickness) of the insulator 200 is reduced in the cross-sectional view shown by the asymmetric geometry.

Insulator 200 also includes a conductive outer surface 214 for carrying ground potential 208. The conductive outer surface 214 extends from the vacuum interface 201 to the environmental interface 202. The angled configuration of the two interfaces 201, 202 is characterized in that the feed-through channel 213 extends from 201 into the insulator 200 in a first direction that is angled to a second direction in which the feed-through channel extends from the environmental interface 202 into the insulator 200. The angle of the exemplary embodiment of fig. 2 is 90 °. However, the technical advantage of reducing the thickness of the insulator along the axis of symmetry of the vacuum interface has been achieved with an angle of at least 5 °. Thus, according to other exemplary embodiments, an angle of 10 °, 15 °, 20 °, 30 °, 45 °, 50 °, 60 °, 70 °, 80 °, or 85 ° may be used to achieve this technical effect.

As can also be seen from fig. 2, the vacuum interface 201 has a virtual axis of symmetry 205 and the environment interface 202 has a virtual axis of symmetry 206. In the embodiment of fig. 2, the angle between the two axes of symmetry is 90 °. Fig. 2 also shows two top views 203 and 204. Top view 203 shows a top view of the environmental interface 202, while top view 204 shows the vacuum interface 201. The conductive feedthrough 207 extending along the feedthrough channel 213 can be seen in the cross-sectional view on the right side of fig. 2, and can also be seen in the top view 204. Thus, when the insulator is applied to an X-ray tube, the vacuum region 211 is in contact with the vacuum interface 201, and the environment interface 202 is in contact with the environment 212. The 90 ° angle of the arrangement in fig. 2 is depicted in fig. 2 with reference numeral 210. The body 209 of the insulator 200 may be made of an isotropic material, such as alumina.

In an embodiment, an X-ray source is provided, wherein an insulator 200 is inserted into the electrical connector at the ambient surface.

According to another exemplary embodiment of the present invention, fig. 3 shows a medical imaging device 300 for generating an X-ray image of a patient. It is clear to the skilled person that this is a schematic simplified diagram. The medical imaging apparatus 300 comprises an X-ray source 302 with an asymmetric X-ray source/X-ray tube insulator 307, which is only schematically shown and only for illustrative purposes. The C-arm 301 further comprises an X-ray detector 303 and a patient table 304. The medical imaging system 300 shown in figure 3 further comprises a display 305 and a control unit 306 to be used by the medical practitioner. Any of the previously mentioned asymmetric insulators of the embodiments of the present invention may be applied and used within the medical imaging system 300 shown in fig. 3.

In the medical imaging device 300, the following exemplary embodiment of the insulator 307 may be used. For example, the entire insulator 307 (including the vacuum and ambient insulator interface) may be composed of a single homogeneous block of isotropic material (e.g., alumina). The block may be manufactured from a plurality of elements which are later joined, for example by sintering or gluing or other techniques. The insulator or a part thereof may be manufactured by 3D printing. In one embodiment, the wafer-type insulator interface (substantially flat, structured, circularly symmetric) on the vacuum side will be accompanied by another insulator interface having an environment with a different axis of symmetry (circularly symmetric or discrete rotational symmetric), where the two axes are angled with respect to each other.

Alternatively, the medical imaging device 300 comprises a wafer insulator interface on the vacuum side followed by an angled conical insulator structure on the ambient side, or vice versa.

In another embodiment of medical imaging device 300, the wafer insulator of the vacuum side is accompanied by a substantially different wafer insulator structure of the ambient side and vice versa.

It can be considered essential to the invention that the insulator has a vacuum side and an ambient side and that the feed-through substantially coincides with an axis of symmetry of the vacuum side and an axis of symmetry of the ambient side, wherein the axis of symmetry of the vacuum side and the axis of symmetry of the ambient side have an angle of at least 5 °, preferably 90 °, with respect to each other.