Electron emitter, electron emitter, X-ray tube, and medical imaging apparatus

Abstract

The invention relates to the technical field of medical instruments, and provides an electron emitter, an electron emitter, an X-ray tube and medical imaging equipment. The electron emitter comprises an emitting part, a non-emitting part and a supporting substrate, the emitting part and the non-emitting part are both arranged on the supporting substrate, and the non-emitting part is arranged on the peripheral side of the emitting part in a surrounding mode; the electron emitter further comprises an isolation part, and the isolation part is arranged on the supporting substrate and located between the emission part and the non-emission part. The electron emitter provided by the invention can ensure that the electron beam is emitted in the direction perpendicular to the emission part as far as possible, reduces the diffusion amount of electrons to the peripheral side of the emission part, further reduces the bending deformation of the electron beam path, and improves the electron distribution uniformity.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to an electron emitter, an electron emitter, an X-ray tube and a medical imaging device. Background Art

[0002] X-ray tube is a high vacuum device that can be used in medical equipment. Its basic principle is that the electron emitter set at the cathode can emit electrons. Under the action of high voltage electric field, the electrons fly to the anode target surface at high speed. The target surface is bombarded by electrons and produces X-rays. In the medical field, X-rays can detect human tissues and help doctors judge the condition of patients.

[0003] The electron-emitting part of the electron emitter has a high resistance value. By applying a voltage to it, the temperature of the electron-emitting part is increased, and it emits hot electrons. However, when the electrons escape, some electrons will be subjected to a large lateral component, especially some electrons near the edge of the emission part have a large lateral component in the initial escape direction. This causes the electrons to diffuse toward both sides of the emission part when escaping, and then, under the influence of the focusing pole of the electron emitter, they are focused and deflected toward the center, which leads to poor image quality of the generated X-ray image. Summary of the invention

[0004] Based on this, it is necessary to provide an electron emitter that can ensure that the electron beam is emitted in a direction perpendicular to the emission portion as much as possible, reduce the diffusion of electrons to the outer peripheral side of the emission portion, thereby reducing the bending deformation of the electron beam path and improving the uniformity of electron distribution.

[0005] An electron emitter comprises a supporting substrate, an emitting portion and a non-emitting portion, wherein both the emitting portion and the non-emitting portion are arranged on the supporting substrate, and the non-emitting portion is arranged around the outer periphery of the emitting portion; the electron emitter also comprises an isolating portion, which is arranged on the supporting substrate and located between the emitting portion and the non-emitting portion.

[0006] It can be understood that a non-emitting part is provided on the outer periphery of the emitting part, and the emitting part and the non-emitting part are blocked by an isolating part to achieve electrical isolation between the emitting part and the non-emitting part. Therefore, the current flowing to the emitting part will not flow to the non-emitting part, and can cause the electron beam of the emitting part to focus as much as possible to the center, reduce the lateral component borne by the electrons at the side of the emitting part, ensure that the electron beam is emitted in a direction perpendicular to the emitting part as much as possible, reduce the diffusion amount to the outer peripheral side, and thus reduce the bending deformation of the electron beam path, and improve the uniformity of electron distribution. In addition, it is precisely because of the setting of the isolating part that the temperature of the non-emitting part can be ensured to be much lower than the heat of the emitting part, thereby reducing the heat transferred from the emitting part to the non-emitting part, and ensuring that the emitting part has sufficient heat for electron escape.

[0007] In some embodiments, the non-emitting portion is continuously disposed around the outer periphery of the emitting portion.

[0008] In some embodiments, there are at least two isolation parts, which are arranged at intervals along the circumference of the emitting part; the emitting part is arranged in the area commonly enclosed by the isolation parts, and the non-emitting part is arranged outside the area commonly enclosed by the isolation parts.

[0009] In some embodiments, the emitting portion and / or the non-emitting portion are integrally formed on the supporting substrate.

[0010] In some of the embodiments, along the circumference of the emitting portion, the region of the support substrate between any two adjacent isolation portions is defined as a current inlet and a current outlet of the emitting portion;

[0011] The emitting portion is provided with a plurality of guide grooves, which are arranged in a staggered manner. The isolating portion is connected to the area between the guide grooves and the area between any adjacent guide grooves, and is connected between the current inlet and the current outlet, thereby jointly defining a current loop.

[0012] In some embodiments, the isolation portion is an isolation groove penetrating the support substrate.

[0013] In some of the embodiments, the electron emitter further comprises a current connection portion, which is disposed on the support substrate and is located within the non-emitting portion, and is connected to a current inlet and a current outlet of the emitting portion.

[0014] In some embodiments, the electron emitter further comprises a heat insulating portion, which is disposed on the supporting substrate and spaced apart on the outside of the isolation portion; wherein the heat insulating portion is at least located at a current inlet of the emission portion and / or a current outlet of the emission portion.

[0015] In some embodiments, the heat insulating portion is a heat insulating groove penetrating the supporting substrate.

[0016] In some embodiments, the heat insulation groove is at least one of an arc groove, a curved groove, and a straight groove extending circumferentially along the emitting portion.

[0017] In some of the embodiments, along the circumference of the emitting portion, the area of ​​the support substrate between the heat insulation portion and the isolation portion is defined as an overlapping area, and the current inlet and / or current outlet of the emitting portion are arranged in the overlapping area; the support substrate is provided with a current connecting portion within the range of the non-emitting portion, and the current connecting portion is connected to the current inlet and / or the current outlet through the overlapping area.

[0018] In some of the embodiments, the width of the overlapping region is 0.5-2 times the width of the current path in the emitting portion.

[0019] In some embodiments, the overlapping area is provided with a first dividing groove, and the first dividing groove divides the overlapping area into a first area and a second area, one of which is connected to the current inlet and the other is connected to the current outlet.

[0020] In some of the embodiments, the supporting substrate is provided with at least one second dividing groove at the emitting portion, and the at least one second dividing groove divides the emitting portion into at least two sub-emitting portions; each of the sub-emitting portions is provided with a plurality of guide grooves, and the plurality of guide grooves are staggered to guide the current path; each of the sub-emitting portions is correspondingly provided with an isolation portion.

[0021] In some of the embodiments, the plurality of guide grooves of each sub-emitting portion are spaced and staggered along the circumferential length of the emitting portion from small to large and from inside to outside, and the area between any two adjacent guide grooves from inside to outside is defined as the current path.

[0022] In some embodiments, the support substrate is provided with a current connection portion within the range of the non-emitting portion;

[0023] Each of the sub-emitting parts is connected in series to the current connecting part to form a current loop; or, some of the sub-emitting parts are connected in series to form a current path, and each of the current paths is connected in parallel to the current connecting part to form a plurality of current loops.

[0024] In some embodiments, the support substrate is provided with a circular hole at the center of the emitting portion, and the circular hole is connected to a portion of the second dividing groove.

[0025] The present application also provides an electron emitter, including the above-mentioned electron emitter, to reduce heat diffusion of the emission part, ensure sufficient electron emission, and avoid the electron emitter from being easily worn out due to long-term heat, thereby extending the service life.

[0026] The present application also provides an X-ray tube, comprising a cathode assembly and an anode assembly, wherein the cathode assembly comprises the above-mentioned electron emitter, and the anode assembly comprises an anode target, wherein the anode target is arranged opposite to and spaced from the electron emitter, and the anode target is configured to generate X-rays in response to electron bombardment of the electron emitter. The X-ray tube has the technical effects of any of the above-mentioned embodiments.

[0027] The present application also provides a medical imaging device, including the above-mentioned X-ray tube, which has the technical effects of any of the aforementioned embodiments and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 A schematic diagram of an electron emitter provided in one embodiment of the present application;

[0030] Figure 2 A schematic diagram of an electron emitter provided in another embodiment of the present application;

[0031] Figure 3 A schematic diagram of an electron emitter provided in yet another embodiment of the present application;

[0032] Figure 4 A simplified cross-sectional view of an electron emitter provided in one embodiment of the present application;

[0033] Figure 5 A schematic diagram of thermal simulation results of an electron emitter provided in one embodiment of the present application;

[0034] Figure 6 A schematic diagram of thermal-structural coupling simulation results of an electron emitter provided in one embodiment of the present application.

[0035] Figure numerals: 10, supporting substrate; 20, isolating part; 30, heat insulating part; 31, heat insulating groove; 41, first dividing groove; 42, second dividing groove; 50, current connecting part; 51, first connecting end; 52, second connecting end; 53, third connecting end; 54, fourth connecting end; 101, emitting part; 101a, first sub-emitting part; 101b, second sub-emitting part; 101c, third sub-emitting part; 101d, fourth sub-emitting part; 102, non-emitting part; 103, circular hole; 201, isolating groove; 1011, current inlet; 1012, current outlet; 1013, guide groove; 1014, current path; 1021, overlapping area. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0037] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it may be directly on the other component or there may also be a central component. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be a central component at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the specification of this application are for illustrative purposes only and do not represent the only implementation method.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0039] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first feature is directly in contact with the second feature, or the first feature and the second feature are indirectly in contact through an intermediate medium. Moreover, a first feature being “above”, “above” or “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below” or “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] Unless otherwise defined, all technical and scientific terms used in the specification of this application have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in the specification of this application includes any and all combinations of one or more related listed items.

[0041] In the related art, the part of the electron emitter used to emit electrons (hereinafter referred to as the emission part) has a high resistance value. By applying a voltage to it to increase the temperature of this part, the kinetic energy of the electrons is increased, and then they escape from the emission part of the electron emitter. When the electrons escape, some electrons will be subjected to a large lateral component, especially some electrons near the edge of the emission part have a large lateral component in the initial escape direction. This causes the electrons to diffuse toward both sides of the emission part when escaping, and then, under the influence of the focusing pole of the electron emitter, they are focused and deflected toward the center. Therefore, in this process, the trajectory of the electrons is curved, which leads to poor image quality of the generated X-ray images.

[0042] Based on this, an embodiment of the present application provides an electron emitter, which not only ensures that the electron beam is emitted in a direction perpendicular to the emission part as much as possible, but also improves the problem of insufficient electron emission caused by heat flow to the emission part. The structure of the electron emitter is described in detail below.

[0043] See also Figures 1 to 4 Exemplarily, the electron emitter includes a support substrate 10, an emission portion 101 and a non-emission portion 102 disposed on the support substrate 10, and the non-emission portion 102 is disposed around the outer periphery of the emission portion 101. The electron emitter also includes an isolation portion 20 disposed on the support substrate 10, and the isolation portion 20 is located between the emission portion 101 and the non-emission portion 102.

[0044] It can be understood that the support substrate 10 is used to install the electron emitter at the target position. For example, a cylindrical structure is provided at the bottom of the support substrate 10 to support the support substrate 10, and the cylindrical structure can be connected to a base for installing the electron emitter. For another example, the base can be provided with a mounting groove, and the electron emitter is fixed in the mounting groove through the support substrate 10. The emission part 101 is a part that is heated by electric current and emits electrons. Since a non-emitting part 102 is provided around the outer periphery of the emission part 101, and the emission part 101 and the non-emitting part 102 are blocked by an isolation part 20, electrical isolation between the emission part 101 and the non-emitting part 102 is achieved. Therefore, the current flowing to the emission part 101 will not flow to the non-emitting part 102, causing the heat of the non-emitting part 102 to be lower than the heat of the emission part 101, thereby ensuring that the electron beam of the emission part 101 is focused toward the center as much as possible. In this way, the lateral component borne by the electrons at the side of the emitting portion 101 can be reduced, ensuring that the electron beam is emitted in a direction perpendicular to the emitting portion 101 as much as possible, reducing the diffusion amount to the peripheral side, thereby reducing the bending deformation of the electron beam path and improving the uniformity of electron distribution. In addition, it is precisely because of the setting of the isolation portion 20 that the current generated by the emitting portion 101 is isolated, which can ensure that the temperature of the non-emitting portion 102 is much lower than the heat of the emitting portion 101, thereby reducing the heat transferred from the emitting portion 101 to the non-emitting portion 102, and ensuring that the emitting portion 101 has sufficient heat for electron escape.

[0045] Please continue reading Figures 1 to 4In some optional embodiments, the non-emitting portion 102 is continuously arranged around the outer periphery of the emitting portion 101. Such a setting not only increases the focusing range of the electrons emitted by the emitting portion 101 and reduces the diffusion amount at the edges of the emitting portion 101 along its own circumference; but also ensures that the non-emitting portion 102 is not discontinuous, so as to ensure the structural strength of the non-emitting portion 102 itself. Since the temperature of the emitting portion 101 can reach above 2000 degrees Celsius when emitting electrons, that is, the temperature is extremely high, if the structural strength of the non-emitting portion 102 itself is low, it is very easy to cause problems such as thermal deformation at high temperatures, thereby affecting the electron focusing problem of the emitting portion 101. Therefore, in this embodiment, by setting the continuous non-emitting portion 102, on the one hand, thermal deformation can be effectively prevented, and on the other hand, sufficient mechanical support is provided to ensure that the electron emitter remains stable in a high-temperature working environment.

[0046] Further, the emitting part 101 and the non-emitting part 102 are integrally formed on the supporting substrate 10. At this time, the isolation part is also integrally formed on the supporting substrate to separate the supporting substrate into the emitting part and the non-emitting part. For example, the isolation part 20 is an isolation groove 201 that runs through the supporting substrate 10. That is to say, based on the setting that the emitting part 101 and the non-emitting part 102 are integrated into the supporting substrate 10, the emitting part 101 and the non-emitting part 102 are physically separated by the setting of the isolation groove 201 that runs through the supporting substrate 10, so that there is no physical connection part between the non-emitting part 102 and the emitting part 101, and thus there is no physical part for current to flow through, so as to better reduce the lateral component borne by the electrons at the side of the emitting part 101, and improve the convergence effect on the electron beam of the emitting part 101. Moreover, it is precisely because of such a setting that the diffusion of heat generated by the emitting part 101 under the action of the current can be blocked as much as possible, so that the heat is concentrated in the emitting part 101 as much as possible, and the problem of insufficient electron emission caused by heat loss in the emitting part 101 is improved. In addition, such a configuration facilitates the integrated molding of the emitting portion 101 and the non-emitting portion 102 on the supporting substrate 10 , thus facilitating production and manufacturing.

[0047] like Figures 1 to 3 Further, at least two isolation parts 20 are provided and arranged at intervals along the circumference of the emitting part 101. The emitting part 101 is provided in the area enclosed by the isolation parts 20, and the non-emitting part 102 is provided outside the area enclosed by the isolation parts 20.

[0048] Each isolation portion 20 is an isolation groove 201 that penetrates along the thickness direction of the support substrate 10, which is equivalent to providing at least two isolation grooves 201 that are spaced apart along the circumference of the emitting portion 101 on the support substrate 10. The portion of the support substrate 10 surrounded by multiple isolation grooves 201 serves as the emitting portion 101, and the portion outside the multiple isolation grooves 201 serves as the non-emitting portion 102. If each isolation groove 201 is an arc-shaped example, the shape surrounded by at least two isolation grooves 201 is a circle, that is, the emitting portion 101 is a circle, and the non-emitting portion 102 is arranged around the outer circumference of the emitting portion 101. Alternatively, each isolation groove 201 may also be a straight line, and then multiple isolation grooves 201 may be arranged in a variety of shapes such as square, triangle, pentagon, etc., and the corresponding emitting portion 101 may be set in a variety of different shapes.

[0049] That is to say, the influence of the emitting part 101 on the non-emitting part 102 is reduced by setting at least two isolation grooves 201; and since the non-emitting part 102 is arranged in a ring relative to the emitting part 101, that is, the non-emitting part 102 is continuously arranged around the outer side of the emitting part 101, the problem of the non-emitting part 102 being easily deformed or broken due to heat is alleviated.

[0050] Furthermore, along the circumference of the emitting portion 101, the region of the supporting substrate 10 between any two adjacent isolation portions 20 is defined as the current inlet 1011 or the current outlet 1012 of the emitting portion 101. At the same time, the emitting portion 101 is provided with a plurality of guide grooves 1013, and the plurality of guide grooves 1013 are arranged in a staggered manner, and the region between the isolation portion 20 and the guide grooves 1013 and the region between any adjacent guide grooves 1013 are connected, and are connected between the current inlet 1011 and the current outlet 1012. Among them, each guide groove 1013 is arranged through the thickness direction of the supporting substrate 10.

[0051] In actual use, the support substrate 10 is provided with a current connection portion 50 within the range of the non-emitting portion 102, and the current connection portion 50 is connected to the current inlet 1011 and the current outlet 1012 of the emitting portion 101. Specifically, the current connection portion 50 includes at least a first connection end 51 and a second connection end 52, and the first connection end 51 may be conductive with the current inlet 1011, and the second connection end 52 may be conductive with the current outlet 1012. In this way, the current flows to the current inlet 1011 via the first connection end 51, flows along the area between the isolation portion 20 and the guide groove 1013 and the area between any two adjacent guide grooves 1013, and then flows out from the current outlet 1012 and flows to the second connection end 52, forming a complete current loop. In this process, the staggered arrangement of the multiple guide grooves 1013 can make the corresponding current path at the emission part 101 larger, that is, it is ensured that the emission part 101 has a larger resistance value for heat generation. For example, the emission part 101 can be heated to a temperature above 2000 degrees Celsius under the action of current, which makes the kinetic energy of electrons on the emission part 101 increase and escape, thereby realizing electron emission.

[0052] Among them, Figure 1 For example, Figure 1 It is shown that two isolation parts 20 (i.e., two isolation grooves 201) are provided, and the two isolation grooves 201 are arranged in an arc shape along the circumference of the emitting part 101, and the ends of the two isolation grooves 201 along the arc extension direction are not connected, but there is a gap, that is, the two isolation parts 20 are arranged at intervals. This gap is divided into the aforementioned current inlet 1011 and current outlet 1012.

[0053] In actual use, the current connection part 50 can be an opening provided on the support substrate 10 to facilitate the connection of conductive parts, such as conductive wires, conductive columns, etc. Alternatively, the current connection part 50 can be a conductive protrusion provided on the support substrate 10 to facilitate the connection of conductive wires, conductive columns, etc.

[0054] Furthermore, the support substrate 10 is mainly made of metal material with a very high melting point, such as tungsten, molybdenum, iridium, etc., and the thickness of the support substrate 10 is between 0.1mm-0.25mm, for example, it can be 0.1mm, 0.13mm, 0.175mm, 0.21mm, 0.235mm or 0.25mm, etc.

[0055] See also Figure 1 , Figure 2 , Figure 3 , Figure 5 and Figure 6As some examples, the electron emitter further includes a heat insulating portion 30, which is disposed on the support substrate 10 and spaced apart outside the isolation portion 20. The heat insulating portion 30 is at least located at the current inlet 1011 and the current outlet 1012 of the emission portion 101. The heat insulating portion 30 is used to block heat transfer.

[0056] In the related art, it is precisely because of the need to apply voltage to the emission part that the emission part has a current inlet and a current outlet. Therefore, when the temperature of the emission part rises under the action of voltage, it is very easy for heat to diffuse outward along the current path at the current inlet and the current outlet, resulting in heat loss in the electron emission part, causing some electrons to fail to reach the escape kinetic energy, resulting in insufficient electron emission. At this time, it may be necessary to increase the voltage to generate more heat to ensure sufficient electron emission, but more heat will cause excessive heat loss of the electron emitter, and long-term use is prone to deformation and other problems.

[0057] That is to say, in this embodiment, since the portion between any two adjacent isolation portions 20 on the support substrate 10 serves as the current inlet 1011 and the current outlet 1012 of the emitting portion 101, and the current connection portion 50 is located in the non-emitting portion 102, when the current is transmitted between the current connection portion 50 and the current inlet 1011 and the current outlet 1012, part of the current is bound to pass through the non-emitting portion 102, which easily causes the heat of the emitting portion 101 to be lost from the current inlet and the current outlet. Therefore, in this embodiment, by setting the heat insulation portion 30 at the current inlet 1011 and the current outlet 1012, the emitting portion 101 can be blocked relative to the non-emitting portion 102, especially from the current inlet 1011 and / or the current outlet 1012, reducing the amount of heat generated by the emitting portion 101 from the current inlet 1011 and the current outlet 1012 to the non-emitting portion 102, ensuring that the heat is concentrated in the emitting portion 101 as much as possible, and improving the problem of insufficient electron emission caused by heat loss in the emitting portion 101. The heat insulating portion 30 is located at the interval between any two adjacent isolation slots 201 to perform heat insulation on the current inlet 1011 and the current outlet 1012 .

[0058] Alternatively, a heat insulating portion 30 may be provided only at the current inlet 1011 , or a heat insulating portion 30 may be provided only at the current outlet 1012 , as long as the heat diffusion of the emitting portion 101 can be reduced.

[0059] In the above-mentioned embodiment, the current inlet 1011 and the current outlet 1012 of the emission part 101 are both provided with a heat insulating part 30 to ensure that the current inlet 1011 and the current outlet 1012 can reduce heat diffusion and improve the heat insulation effect. When the current inlet 1011 and the current outlet 1012 of the emission part 101 are located on the same side of the electron emitter, the two corresponding heat insulating parts 30 can be connected as a whole to jointly block heat diffusion.

[0060] The length of the heat insulating portion 30 along the circumference of the emitting portion 101 is greater than the spacing between any two adjacent isolation slots 201 , thereby increasing the heat insulating range, thereby improving the heat insulating effect, and further reducing the heat diffusion of the current inlet 1011 and the current outlet 1012 .

[0061] like Figures 1 to 3 As shown, further, the heat insulating portion 30 may be a heat insulating groove 31 penetrating the support substrate 10. Since the electron emitter is in a vacuum environment during operation, the provision of the heat insulating groove 31 can ensure that there is no heat conducting medium for the heat, thereby reducing the heat of the emitter 101 from the current inlet 1011 and the current outlet 1012. The provision of the isolation groove 201 can also ensure that there is no heat conducting medium between the emitter 101 and the non-emitter 102, thereby not only reducing the heat loss of the emitter 101, but also reducing the amount of electrons escaping from the emitter 101 diffusing to the peripheral side.

[0062] like Figure 1 As shown, in some specific embodiments, taking the launch part 101 as a circular shape, the heat insulation groove 31 can be an arc groove extending along the circumference of the launch part 101 and is arranged concentrically with the launch part 101. In this case, the distance between the heat insulation groove 31 and the launch part 101 along the circular radial direction is the same at all points along its own extension direction, ensuring that the force is basically consistent. Figure 3 As shown, alternatively, the heat insulation groove 31 can be a straight groove extending along the circumference of the launch part 101, that is, the heat insulation part 30 is also straight. Alternatively, the heat insulation groove 31 can also be a curved groove extending along the circumference of the launch part 101, for example, in a wave shape.

[0063] like Figure 2 As shown, another alternative, the heat insulation groove 31 can also be a combination of the aforementioned arc groove and straight groove, or a combination of an arc groove and a curved groove, or a combination of a curved groove and a straight groove, or a combination of a curved groove, an arc groove and a straight groove. Among them, the arc groove, the curved groove and the straight groove can all be provided with at least one section, or two sections, three sections, or even more sections, and the curvature, slope, etc. of each section can be different, and it is mainly to roughly adapt to the shape of the launch part 101 and play a heat insulation effect.

[0064] Furthermore, taking the electron emitter placed horizontally as an example, the emitter 101 has two sets of current inlets 1011 and current outlets 1012 that are opposite and spaced along the X-axis direction, and heat insulation grooves 31 are respectively arranged on both sides of the emitter 101 along the X-axis direction. The electron emitter has first edges that are opposite and spaced along the Y-axis direction, and the distances from the two ends of each heat insulation groove 31 to the first edge on the same side should not be too large or too small. If it is too large, the length of the heat insulation groove 31 itself is too short, which will weaken the heat insulation effect, and there will still be the problem of heat loss in the emitter 101; if it is too small, the length of the heat insulation groove 31 itself is too long, which will weaken the structural strength of the electron emitter itself and easily deform under the influence of heat.

[0065] In other embodiments, the launch part 101 may also be square, and the corresponding heat insulation groove 31 may be a straight groove, a curved groove, etc., which mainly roughly matches the shape of the launch part 101 and has a heat insulation effect.

[0066] like Figure 1 , Figure 2 , Figure 3 , Figure 5 and Figure 6 As shown, in some embodiments, along the circumference of the emitting portion 101, the area of ​​the supporting substrate 10 between the heat insulating portion 30 and the isolation portion 20 is defined as an overlapping area 1021, and the current inlet 1011 and the current outlet 1012 of the emitting portion 101 are arranged in the overlapping area 1021, and are connected to the current connecting portion 50 through the overlapping area 1021. Since the current connecting portion 50 on the supporting substrate 10 is located on the outer peripheral side of the heat insulating groove 31, this overlapping area 1021 is not only the area where the current enters and exits the emitting portion 101, but also the area where the heat of the emitting portion 101 diffuses outward. Therefore, it is necessary to limit the size of the overlapping area 1021 to meet the current conduction while reducing heat diffusion. The overlapping area 1021 can be understood as the portion of the non-emitting part 102 between the outer contour of the emitting part 101 and the insulation part 30. Therefore, the length of the overlapping area 1021 is equal to the length of the insulation part 30, and the width of the overlapping area 1021 is the distance between the outer contour of the emitting part 101 and the insulation part 30 (the inner wall).

[0067] Specifically, the width of the overlapping area 1021 is 0.5-2 times the width of the current path 1014 in the transmitting part 101. It can be understood that the width of the overlapping area 1021 should not be too large or too small. If the width of the overlapping area 1021 is too large, more heat will diffuse into the overlapping area 1021, resulting in heat loss in the transmitting part 101; if its width is too small, the connection strength of this part of the area will be weakened, and it is easy to deform or break under the influence of heat. In some specific embodiments, the width of the overlapping area 1021 is 0.5 times, 0.85 times, 1.35 times, 1.68 times, 1.9 times or 2 times the width of the current path 1014 in the transmitting part 101.

[0068] See also Figures 1 to 3 , wherein, at the overlapping area 1021, the supporting substrate 10 is constructed with a first dividing groove 41 that penetrates along its own thickness direction, the length of the first dividing groove 41 can extend along the X-axis direction, and the first dividing groove 41 is connected to the heat insulation groove 31. The first dividing groove 41 divides the overlapping area 1021 into a first area and a second area, one of which is connected to the current inlet 1011, and the other is connected to the current outlet 1012. In this way, problems such as short circuit caused by the conduction of the current inlet 1011 and the current outlet 1012 in the overlapping area 1021 can be avoided. For example, the area facing oy may be the first area, the area facing oy' may be the second area, the first area is connected to the current inlet 1011, and the second area is connected to the current outlet 1012. Alternatively, the first area is connected to the current outlet 1012, and the second area is connected to the current inlet 1011. It is sufficient as long as the current can enter and exit the transmitting part 101.

[0069] Please continue reading Figures 1 to 3 Optionally, the support substrate 10 is provided with a plurality of guide grooves 1013 in the emitting portion 101, and each guide groove 1013 extends along the circumference of the emitting portion 101 and is arranged in a staggered manner to jointly guide a current path 1014. Among them, each guide groove 1013 is arranged through the thickness direction of the support substrate 10. The staggered arrangement of the plurality of guide grooves 1013 can make the corresponding current path at the emitting portion 101 larger, that is, ensure that the emitting portion 101 has a larger resistance value that can be used for heat generation and realize electron escape. Of course, the method of grooving the support substrate 10 is convenient for manufacturing and production.

[0070] Among them, the width of the current path 1014 is between 0.2mm and 0.8mm. Among them, along the radial direction of the emission part 101, the area between any two adjacent guide grooves 1013 is used for current conduction. Therefore, the area between any two adjacent guide grooves 1013 along the radial direction is defined as the current path 1014, and the spacing between them is the width of the current path 1014. Such a setting not only has sufficient strength while ensuring the flow of current, but also ensures that the length of the current path 1014 is longer within the area of ​​the effective emission part 101, thereby generating more heat to fully emit electrons. In some specific embodiments, the width of the current path 1014 is 0.2mm, 0.35mm, 0.56mm, 0.68mm, 0.75mm or 0.8mm, etc.

[0071] Please continue reading Figures 1 to 3 In some of the embodiments, the support substrate 10 is provided with at least one second dividing groove 42 at the emitting portion 101, and the at least one second dividing groove 42 divides the emitting portion 101 into at least two sub-emitting portions. Each sub-emitting portion is provided with a plurality of guide grooves 1013, and the plurality of guide grooves 1013 are staggered to guide the current path 1014. Each sub-emitting portion is provided with an isolation portion 20, thereby ensuring that a continuous non-emitting portion 102 is provided on the outer peripheral side of each sub-emitting portion. Among them, the second dividing groove 42 having the same length direction as the first dividing groove 41 is connected to a first dividing groove 41 at both ends along its own length direction, that is, the first dividing groove 41 and the second dividing groove 42 having the same length direction are connected as a whole, so as to realize the separation of the emitting portion 101 and the aforementioned overlapping area 1021.

[0072] Taking a second dividing groove 42 as an example, the length of the second dividing groove 42 extends along the X-axis direction, and the emitting part 101 is divided into two symmetrical parts based on the second dividing groove 42, that is, two sub-emitting parts arranged at intervals along the Y-axis direction. Each sub-emitting part has a corresponding current inlet 1011 and a current outlet 1012, and a set of current inlet 1011 and current outlet 1012 are respectively provided at both ends of the second dividing groove 42 along the X-axis direction, and correspond to a first dividing groove 41 and a heat insulation groove 31 respectively.

[0073] In actual use, the number of the second dividing grooves 42 is N, then the number of sub-emitting parts M=2N, and each sub-emitting part is arranged at intervals around the central axis of the support substrate 10. Taking the case where two second dividing grooves 42 are provided as an example, the number of sub-emitting parts is four, namely the first sub-emitting part 101a, the second sub-emitting part 101b, the third sub-emitting part 101c and the fourth sub-emitting part 101d. The two ends of a second dividing groove 42 along the X axis are respectively connected to a first dividing groove 41 and a heat insulation groove 31, and the two ends of a second dividing groove 42 along the Y axis pass through the edge of the support substrate 10. The current connecting part 50 on the support substrate 10 includes a first connecting end 51, a second connecting end 52 and a third connecting end 53, and the first connecting end 51 and the second connecting end 52 may be arranged oppositely and at intervals along the X axis, and the first connecting end 51 and the third connecting end 53 may be arranged oppositely and at intervals along the Y axis.

[0074] like Figure 1 and Figure 2 As shown, the first sub-emitter 101a, the second sub-emitter 101b, the third sub-emitter 101c and the fourth sub-emitter 101d may be connected in series between the first connection terminal 51 and the second connection terminal 52 to form a first current loop. At this time, the current inlet 1011 of the first sub-emitter 101a may be connected to the first connection terminal 51, and the current outlet 1012 of the fourth sub-emitter 101d may be connected to the second connection terminal 52. One of the heat-insulating grooves 31 is provided at the current inlet 1011 of the first sub-emitter 101a and the current inlet 1011 of the fourth sub-emitter 101d, and the other heat-insulating groove 31 is provided at the current outlet 1012 of the second sub-emitter 101b and the current inlet 1011 of the third sub-emitter 101c, and both heat-insulating grooves 31 are connected to the first dividing groove 41.

[0075] Alternatively, the first sub-emitting unit 101a and the second sub-emitting unit 101b may be connected in series to form a first flow path, and the two ends thereof are respectively connected to the first connection end 51 and the third connection end 53. The third sub-emitting unit 101c and the fourth sub-emitting unit 101d may be connected in series to form a second flow path, and the two ends of the second flow path are respectively connected to the second connection end 52 and the third connection end 53, and the second flow path and the first flow path are arranged in parallel.

[0076] like Figure 3As shown, another alternative is that two groups of current inlets 1011 and current outlets 1012 are arranged on both sides of the support substrate 10 along the Y-axis direction, and the first dividing grooves 41 corresponding to each group of current inlets 1011 and current outlets 1012 penetrate to the edge of the support substrate 10 and communicate with a second dividing groove 42 with the same length direction. At this time, the first sub-emitting part 101a and the fourth sub-emitting part 101d are connected in series to form a third flow path, and the two ends thereof are respectively connected to the first connection end 51 and the second connection end 52, and the current inlet 1011 of the first sub-emitting part 101a and the current outlet 1012 of the fourth sub-emitting part 101d are arranged oppositely and at intervals along the Y-axis direction. The second sub-emitting part 101b and the third sub-emitting part 101c are connected in series to form a fourth flow path, and the two ends thereof are respectively connected to the third connection end 53 and the fourth connection end 54, and the current inlet 1011 of the second sub-emitting part 101b and the current outlet 1012 of the third sub-emitting part 101c are arranged oppositely and at intervals along the Y-axis direction. At this time, the heat insulation grooves 31 are arranged at both ends of the emitting part 101 along the Y-axis direction, and a heat insulation groove 31 may be correspondingly arranged at each current inlet 1011 and each current outlet 1012 .

[0077] like Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, in some embodiments, the support substrate 10 is provided with a circular hole 103 at the center of the emitting portion 101, and the circular hole 103 is connected to the second dividing groove 42 corresponding to the heat insulation groove 31. By providing the circular hole 103, it can be ensured that the width of the current path 1014 at the center of the emitting portion 101 is consistent with the width of the current path 1014 in other areas.

[0078] Another embodiment of the present application provides an electron emitter, comprising the aforementioned electron emitter and the aforementioned base, wherein the electron emitter is mounted on the base via a cylindrical structure connected to a supporting substrate for emitting electrons. The electron emitter has the technical effects of any of the aforementioned embodiments, which will not be described in detail herein.

[0079] Another embodiment of the present application provides an X-ray tube, including a cathode assembly and an anode assembly, the cathode assembly includes the aforementioned electron emitter, the anode assembly includes a metal target, the metal target and the electron emitter are arranged relative to each other and at intervals, and the electrons emitted by the emission part after heating can collide with the metal target after acceleration to form X-rays.

[0080] The present application also provides a medical imaging device, including a power supply, a console, a high-voltage generator and an X-ray tube, wherein the console is connected to the power supply, the high-voltage generator is connected to the console, and the X-ray is connected to the high-voltage generator; the power supply provides power support for each device, the console is used to convert the single input voltage of the power supply network into an adjustable voltage to meet the different power supply requirements of different devices, the high-voltage generator is used to increase the voltage and rectify the output to provide DC high voltage for the X-ray tube, and the X-ray tube is used to emit X-rays.

[0081] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0082] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of patent protection of the present application shall be subject to the attached claims.

Claims

1. An electron emitter, characterized in that: It comprises a supporting substrate (10), an emitting portion (101) and a non-emitting portion (102), wherein the emitting portion (101) and the non-emitting portion (102) are both arranged on the supporting substrate (10), and the non-emitting portion (102) is arranged around the outer periphery of the emitting portion (101); The electron emitter further comprises an isolation portion (20), wherein the isolation portion (20) is provided on the support substrate (10) and is located between the emission portion (101) and the non-emission portion (102).

2. The electron emitter according to claim 1, characterized in that The non-emitting portion (102) is continuously arranged around the outer periphery of the emitting portion (101).

3. The electron emitter according to claim 1, characterized in that At least two isolation parts (20) are provided and are arranged at intervals along the circumference of the emitting part (101); The emitting portion (101) is arranged in an area commonly enclosed by the isolation portions (20), and the non-emitting portion (102) is arranged outside the area commonly enclosed by the isolation portions (20).

4. The electron emitter according to claim 1 or 3, characterized in that: The emitting portion (101) and / or the non-emitting portion (102) are integrally formed on the supporting substrate (10).

5. The electron emitter according to claim 3, characterized in that Along the circumference of the emitting portion (101), the region of the supporting substrate (10) between any two adjacent isolation portions (20) is defined as a current inlet (1011) and a current outlet (1012) of the emitting portion (101); The transmitting portion (101) is provided with a plurality of guide grooves (1013), the plurality of guide grooves (1013) are arranged in a staggered manner, the isolation portion (20) is connected to the area between the guide grooves (1013) and the area between any adjacent guide grooves (1013), and is connected between the current inlet (1011) and the current outlet (1012), thereby jointly defining a current loop.

6. The electron emitter according to claim 1, characterized in that The isolation portion (20) is an isolation groove (201) that penetrates the support substrate (10).

7. The electron emitter according to claim 1, characterized in that The electron emitter further comprises a current connection portion (50), wherein the current connection portion (50) is disposed on the support substrate (10) and is located within the range of the non-emitting portion (102), and the current connection portion (50) is connected to a current inlet (1011) and a current outlet (1012) of the emitting portion (101).

8. The electron emitter according to claim 1, characterized in that The electron emitter further comprises a heat insulating portion (30), wherein the heat insulating portion (30) is provided on the support substrate (10) and is arranged at intervals along the circumferential direction on the outer side of the isolation portion (20); Wherein, the heat insulation part is located at least at the current inlet (1011) of the transmitting part (101) and / or the current outlet (1012) of the transmitting part (101).

9. The electron emitter according to claim 8, characterized in that The heat insulating portion (30) is a heat insulating groove (31) penetrating the supporting substrate (10).

10. The electron emitter according to claim 9, characterized in that The heat insulation groove (31) is at least one of an arc-shaped groove, a curved groove, and a straight groove extending in the circumferential direction of the emitting portion (101).

11. The electron emitter according to claim 8, characterized in that Along the circumference of the emitting portion (101), the region of the supporting substrate (10) between the heat insulating portion (30) and the isolation portion (20) is defined as an overlapping region (1021), and the current inlet (1011) and / or the current outlet (1012) are arranged in the overlapping region (1021); The support substrate (10) is provided with a current connection portion (50) within the range of the non-emitting portion (102), and the current connection portion (50) is connected to the current inlet (1011) and / or the current outlet (1012) through the overlapping area (1021).

12. The electron emitter according to claim 11, characterized in that The width of the overlapping region (1021) is 0.5-2 times the width of the current path (1014) in the emitting portion (101).

13. The electron emitter according to claim 11, characterized in that The overlapping area (1021) is provided with a first dividing groove (41), and the first dividing groove (41) divides the overlapping area (1021) into a first area and a second area, one of which is connected to the current inlet (1011) and the other is connected to the current outlet (1012).

14. The electron emitter according to claim 1, characterized in that The support substrate (10) is provided with at least one second dividing groove (42) at the emitting portion (101), and the at least one second dividing groove (42) divides the emitting portion (101) into at least two sub-emitting portions; Each of the sub-emitting parts is provided with a plurality of guide grooves (1013), and the plurality of guide grooves (1013) are arranged in a staggered manner to guide a current path (1014); Each of the sub-emitting parts is correspondingly provided with an isolation part (20).

15. The electron emitter according to claim 14, characterized in that The lengths of the plurality of guide grooves (1013) of each sub-launching portion along the circumference of the launching portion (101) are from small to large. 、 The current path (1014) is defined as a region between any two adjacent guide grooves (1013) spaced and staggered from the inside to the outside.

16. The electron emitter according to claim 14, characterized in that The support substrate (10) is provided with a current connection portion (50) within the range of the non-emitting portion (102); Each of the sub-emitting parts is connected in series to the current connecting part (50) to form a current loop; or, some of the sub-emitting parts are connected in series to form a flow path, and each of the flow paths is connected in parallel to the current connecting part (50) to form a plurality of current loops.

17. The electron emitter according to claim 14, characterized in that The support substrate (10) is provided with a circular hole (103) at the center of the emitting portion (101), and the circular hole (103) is connected to a portion of the second dividing groove (42).

18. An electron emitter, characterized in that: An electron emitter comprising the electron emitter according to any one of claims 1 to 17.

19. An X-ray tube, characterized in that: The invention comprises a cathode assembly and an anode assembly, wherein the cathode assembly comprises the electron emitter according to claim 18, and the anode assembly comprises an anode target, wherein the anode target is arranged opposite to and spaced from the electron emitter, and the anode target is configured to generate X-rays in response to electron bombardment of the electron emitter.

20. A medical imaging device, characterized in that: Comprising the X-ray tube as claimed in claim 19.

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