An easily assembled gated array cold cathode electron gun

Abstract

The application discloses a gate-controlled array type cold cathode electron gun easy to assemble and relates to the technical field of vacuum electron devices.The application comprises a cathode substrate, an array type cold cathode assembly is arranged on the upper portion of the cathode substrate, and positioning protrusions are arranged on the outer periphery; a groove type insulation connecting body is sleeved on the outer periphery of the cathode substrate, a positioning groove matched with the positioning protrusions is arranged on the inner side of the groove type insulation connecting body, a stepped surface for bearing a sunken grid is arranged on the upper portion, and a plurality of grid holes arranged opposite to the array type cold cathode assembly are arranged on the sunken grid; a slidable ring is further sleeved on the outer periphery of the cathode substrate, the slidable ring is in abutment with the groove type insulation connecting body, and the inner side groove of the slidable ring is matched with the positioning protrusions.The application can reduce the positional deviation between the grid and the cold cathode array in the assembling process, improve the alignment consistency of the two, and facilitate the adjustment of the axial position of the sunken grid.

Description

Technical Field

[0001] This invention relates to the field of vacuum electronic device technology, specifically to an easy-to-assemble grid-controlled array type cold cathode electron gun. Background Technology

[0002] Grid-controlled array cold cathode electron guns typically use the grid electric field to modulate the electron emission of the array cold cathode. To ensure that each cold cathode emitting unit can form a stable electron transmission channel with the corresponding grid aperture, the grid and the cold cathode array need to maintain a high positional accuracy, especially the lateral alignment between the grid aperture and the cold cathode emitting unit, as well as the axial spacing between the grid and the cold cathode.

[0003] In existing grid-controlled array cold cathode electron guns, the cathode, grid, and their supporting components are typically machined separately before assembly. Machining and assembly errors of each component tend to accumulate gradually during assembly, and the positional relationship between the grid and the cold cathode array often requires repeated manual adjustments. Because array-type cold cathodes have a large number of emitting units and small grid apertures, circumferential offset, lateral misalignment, or axial positional deviation of the grid during assembly can easily cause some grid apertures to deviate from their corresponding cold cathode emitting units, increasing the likelihood of electrons being intercepted by the grid and affecting the operational consistency of each emitting unit. Summary of the Invention

[0004] The purpose of this invention is to provide an easy-to-assemble grid-controlled array cold cathode electron gun to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an easy-to-assemble grid-controlled array cold cathode electron gun, comprising a cathode substrate, an array cold cathode assembly disposed on the upper part of the cathode substrate, and positioning protrusions disposed on the outer periphery of the cathode substrate; The cathode substrate is fitted with a groove-shaped insulating connector on its outer periphery. The inner side of the groove-shaped insulating connector is provided with a positioning groove that matches the positioning protrusion. The upper part of the groove-shaped insulating connector is provided with a stepped surface. A sunken grid is installed on the stepped surface, and the sunken grid is provided with multiple grid holes, which are arranged opposite to the array-type cold cathode assembly. A slidable ring is fitted around the outer periphery of the cathode substrate. The upper part of the slidable ring abuts against the lower part of the groove-shaped insulating connector, and a groove is formed on the inner side of the slidable ring to cooperate with the positioning protrusion.

[0006] Furthermore, multiple positioning protrusions are provided, and the multiple positioning protrusions are arranged at equal intervals along the outer periphery of the cathode substrate. Multiple positioning grooves are provided, and each groove corresponds to and cooperates with one of the multiple positioning protrusions.

[0007] Furthermore, the groove-shaped insulating connector has an internal cavity sleeved on the outer periphery of the cathode substrate, the internal cavity having a columnar structure, wherein a stepped surface is formed on the upper part of the internal cavity.

[0008] Furthermore, the array-type cold cathode assembly includes multiple cold cathode units arranged in an array, each of which is rectangular in shape. Multiple grid holes correspond to the shape and size of the multiple cold cathode units, and the center of each grid hole is aligned with the center of the corresponding cold cathode unit.

[0009] Furthermore, the slidable ring is coaxially arranged with the cathode substrate, and there are multiple grooves opened in the slidable ring. The multiple grooves are arranged at equal intervals along the inner circumference of the slidable ring and correspond to and cooperate with the multiple positioning protrusions.

[0010] Furthermore, the sunken grid has a sheet-like structure, with multiple grid holes disposed in the central region of the sunken grid, and the non-perforated region of the sunken grid surrounding the multiple grid holes is in contact with the stepped surface; An insulating ring is provided on the side of the sunken grid away from the groove-shaped insulating connector, and a tubular gathering electrode is provided on the side of the insulating ring away from the sunken grid.

[0011] Furthermore, the grooved insulating connector, the sunken grid, the insulating ring, and the tubular gathering pole are stacked sequentially from bottom to top, and threaded holes are opened at corresponding positions on the grooved insulating connector, the insulating ring, and the tubular gathering pole. A connecting hole corresponding to the threaded hole is opened on the sunken grid. The grooved insulating connector, the sunken grid, the insulating ring, and the tubular gathering pole are fixed by screws, and the screws pass through the connecting holes and are threadedly connected to the threaded holes.

[0012] Furthermore, a cathode base is installed at the lower part of the cathode substrate. The cathode base has a columnar structure and a stepped surface is provided on the outer edge of the cathode base.

[0013] Furthermore, an insulating shell assembly is fixedly installed on the stepped surface of the cathode base. The insulating shell assembly includes a lower sleeve, a middle sleeve, and an upper sleeve arranged sequentially along the axial direction. The cathode base is sealed to the lower part of the lower sleeve.

[0014] Furthermore, an annular grid sheet is installed between the lower sleeve and the middle sleeve, and the annular grid sheet abuts against the edge area of ​​the recessed grid. An annular focusing electrode is installed between the middle sleeve and the upper sleeve, and the annular focusing electrode abuts against the edge region of the tubular focusing electrode.

[0015] This invention has at least the following beneficial effects: 1. The present invention enables the slot-shaped insulating connector to be stably positioned relative to the cathode substrate by the cooperation of the positioning protrusion and the positioning groove, which is beneficial to improving the alignment consistency between the sunken grid and the array-type cold cathode assembly and reducing assembly deviation.

[0016] 2. By setting the sunken grid on the stepped surface of the slotted insulating connector and arranging the grid holes corresponding to the arrayed cold cathode assembly, the present invention helps to maintain the positional correspondence between the grid holes and the cold cathode emitting unit and reduces the obstruction of electron transmission.

[0017] 3. The present invention provides a sliding ring that abuts against the groove-shaped insulating connector, and the inner groove of the ring engages with the positioning protrusion, which facilitates the adjustment of the axial position of the sunken grid and reduces circumferential offset during the adjustment process.

[0018] 4. By sequentially arranging the sunken grid, insulating ring, and tubular focusing electrode along the axial direction, the present invention enables the grid control and focusing structure to form a compact assembly relationship, which is beneficial to improving the installation stability of the internal structure of the electron gun.

[0019] 5. The present invention uses a tubular focusing electrode to focus the electron beam drawn out through the grid hole, which is beneficial to improving the transmission state of the electron beam.

[0020] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of the grid-controlled array cold cathode electron gun described in this invention; Figure 2 This is a schematic diagram of the installation structure of the sunken grid and the cathode substrate in this invention; Figure 3 This is a top view schematic diagram of the cathode substrate structure in this invention; Figure 4 This is a top view schematic diagram of the sunken grid structure of the present invention; Figure 5 This is a distribution diagram of the applied magnetic field as the device height changes, provided by the present invention.

[0023] Figure label: 1. Cathode substrate; 2. Groove insulating connector; 3. Arrayed cold cathode assembly; 4. Submerged grid; 5. Insulating ring; 6. Tubular focusing electrode; 7. Sliding ring; 8. Cathode base; 901. Lower sleeve; 902. Middle sleeve; 903. Upper sleeve; 1001. Annular grid electrode sheet; 1002. Annular focusing electrode sheet; 11. Anode tube; 12. Acrylic glass window. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] Example 1: This embodiment provides an easily assembled grid-controlled array cold cathode electron gun, which can be applied to field emission electron source structures in vacuum electronic devices, referring to... Figure 1 Specifically, it includes a cathode substrate 1, an array-type cold cathode assembly 3 on the upper part of the cathode substrate 1, a positioning protrusion on the outer periphery of the cathode substrate 1, a groove-type insulating connector 2 on the outer periphery of the cathode substrate 1, a positioning groove that cooperates with the positioning protrusion on the inner side of the groove-type insulating connector 2, a stepped surface formed on the upper part of the groove-type insulating connector 2, a recessed grid 4 on the stepped surface, multiple grid holes of the recessed grid 4 arranged opposite to the array-type cold cathode assembly 3, a sliding ring 7 on the outer periphery of the cathode substrate 1, the sliding ring 7 located below the groove-type insulating connector 2, the upper part of the sliding ring 7 abutting against the lower part of the groove-type insulating connector 2, and a groove that cooperates with the positioning protrusion on the inner side of the sliding ring 7. Through the above structure, the groove-type insulating connector 2, the recessed grid 4 and the sliding ring 7 can all use the positioning protrusion on the cathode substrate 1 as the assembly reference, reducing the need for manual alignment of each component, and providing a structural basis for the positional correspondence between the array-type cold cathode assembly 3 and the recessed grid 4. During assembly, the slotted insulating connector 2 is fitted onto the outer periphery of the cathode substrate 1, aligning the positioning groove on the inner side of the slotted insulating connector 2 with the corresponding positioning protrusion on the outer periphery of the cathode substrate 1. Then, the recessed grid 4 is placed on the stepped surface on the upper part of the slotted insulating connector 2, so that the grid hole area of ​​the recessed grid 4 is located above the array-type cold cathode assembly 3. Subsequently, the sliding ring 7 is fitted onto the outer periphery of the cathode substrate 1, aligning the groove on the inner side of the sliding ring 7 with the positioning protrusion, and the upper part of the sliding ring 7 abuts against the lower part of the slotted insulating connector 2. When the sliding ring 7 is pushed upward, it forms an axial push against the slotted insulating connector 2, causing the slotted insulating connector 2 and the recessed grid 4 above it to adjust their axial positions accordingly. Through the above assembly method, the axial position of the recessed grid 4 can be adjusted while maintaining the matching relationship between the positioning protrusion and the positioning groove, thereby reducing the possibility of circumferential displacement when adjusting the position of the recessed grid 4.

[0026] In one embodiment, a plurality of positioning protrusions are provided on the outer periphery of the cathode substrate 1, and the plurality of positioning protrusions are distributed at intervals along the circumference of the cathode substrate 1. A plurality of positioning grooves are provided on the inner side of the groove-shaped insulating connector 2, and each positioning groove cooperates with a corresponding positioning protrusion. Figure 3 Multiple positioning protrusions arranged circumferentially can be seen on the outer periphery of the cathode substrate 1 shown. Through the cooperation of multiple positioning protrusions and positioning grooves, the circumferential position of the groove-type insulating connector 2 relative to the cathode substrate 1 can be constrained at multiple points, reducing the possibility of the groove-type insulating connector 2 deflecting under single-point positioning state, and helping to maintain the consistency of the circumferential position of the sunken grid 4 relative to the array-type cold cathode assembly 3. In one embodiment, the slot-shaped insulating connector 2 has an internal cavity sleeved on the outer periphery of the cathode substrate 1. The internal cavity has a double-step columnar structure. The cathode substrate 1 extends into the internal cavity, and the recessed grid 4 is supported on the stepped surface formed on the upper part of the internal cavity. In a specific embodiment, the slot-shaped insulating connector 2 is made of polytetrafluoroethylene material with an outer diameter of 13 mm, an inner upper cylindrical section diameter of 8 mm, an inner upper cylindrical section height of 1.9 mm, an inner lower cylindrical section diameter of 6 mm, and an inner lower cylindrical section height of 3 mm. The dimensions of each positioning slot match the corresponding positioning protrusions on the outer periphery of the cathode substrate 1. The double-step internal cavity simultaneously forms the receiving area of ​​the cathode substrate 1 and the supporting area of ​​the recessed grid 4, which enables the cathode substrate 1 and the recessed grid 4 to establish a stable spatial positional relationship through the same slot-shaped insulating connector 2 and reduces the setting of additional independent grid supports. Furthermore, the cathode substrate 1 is cylindrical. In one specific embodiment, the cathode substrate 1 is made of stainless steel, with a cylinder diameter of 6 mm and a height of 5 mm. The positioning protrusions on the outer periphery of the cathode substrate 1 have a height of 3 mm and a width of 0.5 mm. The positioning protrusions respectively form corresponding fits with the positioning groove of the slot-type insulating connector 2 and the groove on the inner side of the sliding ring 7. By having the same set of positioning protrusions participate in the assembly of the slot-type insulating connector 2 and the sliding ring 7 at the same time, the cumulative positional deviation that may be caused by using different positioning references can be reduced, so that the two components have a more consistent assembly reference relative to the cathode substrate 1.

[0027] In one embodiment, the array-type cold cathode assembly 3 includes a plurality of cold cathode units arranged in an array. The plurality of cold cathode units are disposed on the upper surface of the cathode substrate 1. A plurality of grid holes are disposed in the middle region of the recessed grid 4. The plurality of grid holes correspond one-to-one with the plurality of cold cathode units. The center of each grid hole is aligned with the center of the corresponding cold cathode unit. Through the one-to-one correspondence between the grid holes and the cold cathode units, each cold cathode unit can form a relatively independent electron emission channel, reducing the situation where electrons are blocked by the grid due to misalignment of the grid holes and the cold cathode units, and helping to improve the consistency of the emission state of each array unit. Furthermore, each cold cathode unit is rectangular in shape, and each gate hole corresponds to the corresponding cold cathode unit in shape and size. In a specific processing scheme, the upper surface of the cathode substrate 1 is wire-cut to form an array of trenches, and multiple rectangular cold cathode units are formed by adjacent trenches. The side length of a single cold cathode unit is 0.4 mm, the trench depth is 0.2 mm, and the trench width is 0.1 mm. After forming the array structure, a cold cathode material layer is set on the upper surface of each cold cathode unit. The boundaries of each cold cathode unit are defined by the regular array trenches, and the size of the cold cathode unit is matched with the corresponding gate hole of the sunken grid 4, which can further improve the feasibility of positional registration between the gate hole and the cold cathode unit.

[0028] Furthermore, a cold cathode material layer is disposed on the surface of each cold cathode unit. The cold cathode material layer can be one of graphite, graphene, diamond film, carbon nanotube, carbon nanofiber, zinc oxide nanowire or tin oxide nanowire. The cold cathode material layer is disposed on the upper surface of the rectangular cold cathode unit. By disposing of a cold cathode material layer on the surface of each array unit, multiple distributed field emission regions can be formed, enabling the array-type cold cathode assembly 3 to generate array-type electron emission under the action of the gate electric field. Furthermore, the array-type cold cathode assembly 3 can be formed by wire cutting the upper surface of the cathode substrate 1 to create array trenches. The trench depth can be in the range of 0.1 mm to 0.3 mm. The sunken grid 4 can be made of a metal sheet with a thickness in the range of 0.04 mm to 0.08 mm. The central area of ​​the metal sheet is then laser-processed to form multiple grid holes arranged in an array. By using wire cutting to form the boundary of the cold cathode array and laser processing to form the grid hole array, the two types of array structures can be processed according to preset dimensions, providing a structural basis for subsequent assembly using mechanical positioning structures.

[0029] In one embodiment, the slidable ring 7 has an annular structure and is sleeved on the outer periphery of the cathode substrate 1. Multiple grooves are provided on the inner periphery of the slidable ring 7. The multiple grooves are arranged at intervals along the inner periphery of the slidable ring 7 and respectively cooperate with multiple positioning protrusions on the outer periphery of the cathode substrate 1. In a specific embodiment, the slidable ring 7 is made of polytetrafluoroethylene material, with an outer diameter of 13mm, an inner diameter of 8mm, and a height of 0.3mm. The size of each groove matches the size of the corresponding positioning protrusion. By cooperating with multiple grooves and multiple positioning protrusions, the circumferential deflection of the slidable ring 7 relative to the cathode substrate 1 can be restricted when the slidable ring 7 moves axially, so that the slidable ring 7 forms a relatively stable axial push against the groove-shaped insulating connector 2.

[0030] In one embodiment, the recessed grid 4 has a circular sheet structure, with multiple grid holes concentrated in the central area of ​​the recessed grid 4. The annular non-perforated area surrounding the grid holes contacts the stepped surface on the upper part of the groove-shaped insulating connector 2. In a specific embodiment, the recessed grid 4 is made of stainless steel sheet with an outer diameter of 14 mm, a diameter of 8 mm in the central grid hole area, a sheet thickness of 0.06 mm, a side length of 0.4 mm for a single grid hole, and a wire width of 0.1 mm between adjacent grid holes. By supporting the non-perforated area on the stepped surface, the groove-shaped insulating connector 2 can be prevented from directly blocking the central grid hole area. At the same time, the outer non-perforated area forms a continuous support surface, so that the recessed grid 4 maintains a relatively stable planar state after assembly.

[0031] Furthermore, an insulating ring 5 is provided on the side of the sunken grid 4 away from the slot-shaped insulating connector 2, and a tubular focusing electrode 6 is provided on the side of the insulating ring 5 away from the sunken grid 4. The slot-shaped insulating connector 2, the sunken grid 4, the insulating ring 5, and the tubular focusing electrode 6 are stacked sequentially along the electron gun axis. The insulating ring 5 is located between the sunken grid 4 and the tubular focusing electrode 6. In one specific embodiment, the insulating ring 5 is made of polytetrafluoroethylene material, with an outer diameter of 13 mm, an inner diameter of 8 mm, and a height of 0.4 mm. By providing the insulating ring 5 between the sunken grid 4 and the tubular focusing electrode 6, an insulating gap can be formed between the two, and the insulating ring 5 is used to axially support the tubular focusing electrode 6, so that the gate structure and the focusing structure can be arranged sequentially along the same axis. Furthermore, corresponding connection positions are provided on the edge areas of the slotted insulating connector 2, the recessed grid 4, the insulating ring 5, and the tubular clustering electrode 6. Threaded holes are correspondingly opened on the slotted insulating connector 2, the insulating ring 5, and the tubular clustering electrode 6. Connection holes corresponding to the threaded holes are opened on the recessed grid 4. Screws pass through the connection holes on the recessed grid 4 and connect with the corresponding threaded holes, so that the slotted insulating connector 2, the recessed grid 4, the insulating ring 5, and the tubular clustering electrode 6 form an axially stacked connection structure. In one specific embodiment, M1 screws are used. The diameter of the connection hole on the recessed grid 4 is larger than the diameter of the threaded hole on the adjacent component. Through the above connection structure, the axial stacking relationship of each layer of components can be maintained while the components are assembled as a whole, and the possibility of the recessed grid 4 being directly electrically connected to the tubular clustering electrode 6 through the fastening screw is reduced. In one embodiment, the tubular focusing electrode 6 has an axially penetrating inner cavity. The upper part of the inner cavity has a columnar structure, and the lower part of the inner cavity has an inverted frustum structure. An annular protrusion is provided on the lower half of the outer periphery of the tubular focusing electrode 6. In a specific embodiment, the tubular focusing electrode 6 is made of stainless steel with an outer diameter of 9.3 mm, an inner columnar cavity with a diameter of 8.8 mm and a corresponding height of 0.5 mm, an inner inverted frustum with an upper diameter of 8.8 mm, a lower diameter of 6.8 mm, and a height of 4.24 mm, and an outer annular protrusion with a diameter of 13.6 mm and a height of 1 mm. By continuously arranging the columnar cavity and the inverted frustum cavity along the electron transport direction, a gradually converging transport space can be formed for the electron beam passing through the sinking grid 4, and electron beam compression can be achieved in conjunction with the subsequent external magnetic field. Furthermore, a cathode base 8 is provided at the lower part of the cathode substrate 1. The cathode base 8 has a double-stepped truncated column structure and is connected to the lower surface of the cathode substrate 1. In the fully assembled state, the cathode base 8 is located below the sliding ring 7. The cathode base 8 forms a support for the lower end of the cathode substrate 1, which can provide a stable lower mounting reference for the cathode assembly and facilitate the sealed assembly of the cathode assembly and the electron gun housing. In one embodiment, the electron gun insulating shell includes a lower sleeve 901, a middle sleeve 902, and an upper sleeve 903 arranged sequentially along the axial direction. The cathode base 8 is sealed to the lower part of the lower sleeve 901. The lower sleeve 901, the middle sleeve 902, and the upper sleeve 903 surround the cathode assembly, the sunken grid 4, and the tubular focusing electrode 6. After assembly, the inside of the electron gun insulating shell is evacuated to form a vacuum working space. The segmented sleeve structure can provide assembly interfaces for the grid electrical connection position and the focusing electrode electrical connection position, and at the same time form the vacuum environment required for electron emission and transmission. Furthermore, an annular grid electrode 1001 is provided between the lower sleeve 901 and the middle sleeve 902, and the annular grid electrode 1001 is connected to the edge region of the sunken grid 4. An annular cluster electrode 1002 is provided between the middle sleeve 902 and the upper sleeve 903, and the annular cluster electrode 1002 is connected to the edge region of the tubular cluster electrode 6. By arranging the annular grid electrode 1001 and the annular cluster electrode 1002 between different sleeves, external electrical connection positions of the sunken grid 4 and the tubular cluster electrode 6 can be formed respectively, which facilitates the application of corresponding working potentials to the two electrodes respectively and reduces mutual interference between their electrical connection paths.

[0032] In one embodiment, the cathode substrate 1, the grooved insulating connector 2, the sunken grid 4, the insulating ring 5, the tubular focusing electrode 6, and the sliding ring 7 are arranged coaxially, with each component using the axis of the cathode substrate 1 as a common assembly axis. Figure 2 In the complete electron gun structure shown, the cathode base 8 and the anode cylinder 11 are also arranged along the axis. Through the above coaxial structure, the array-type cold cathode assembly 3, the sunken grid 4, the tubular focusing electrode 6 and the anode cylinder 11 can form a continuous axial channel along the electron transport direction, reducing the impact of the axial offset of each functional component on the electron beam transport path. Furthermore, the upper end of the upper sleeve 903 is provided with a device for sealing the upper port. Figure 2 The structure shown includes an anode cylinder 11 and an organic glass window 12 located at the upper end of the anode cylinder 11. The anode cylinder 11 has an axially extending inner cavity, the upper part of which is columnar and the lower part is frustoconical. In one specific embodiment, the outer diameter of the anode cylinder 11 is 6 mm, the diameter of the inner columnar cavity is 2 mm, the height is 15.9 mm, the upper diameter of the inner frustoconical cavity is 2 mm, the lower diameter is 5 mm, and the height is 4.1 mm. By axially arranging the anode cylinder 11 with the front cathode assembly, the sinking grid 4, and the tubular focusing electrode 6, a continuous structure from electron emission, grid extraction, electron beam focusing to anode transmission can be formed, and the upper closed structure is used to maintain the vacuum environment inside the electron gun. In one specific operating mode, the cathode substrate 1 is connected to a low potential, the array-type cold cathode assembly 3 is kept at the same potential as the cathode substrate 1, the submerged grid 4 is connected to a potential higher than the cathode substrate 1, the tubular focusing electrode 6 is connected to a potential lower than the submerged grid 4, and the anode cylinder 11 is connected to a potential higher than the tubular focusing electrode 6. In a set of simulation parameters, the potential of the cathode substrate 1 and the array-type cold cathode assembly 3 is 0V, the potential of the submerged grid 4 is 1.19kV, the potential of the tubular focusing electrode 6 is 0V, and the potential of the anode cylinder 11 is 25kV. An external magnetic field that varies with the device height is set along the axis of the electron gun. Through the above potential relationship, the electric field required for field emission can be formed between the array-type cold cathode assembly 3 and the submerged grid 4, and the electrons passing through the grid holes continue to be transmitted towards the anode cylinder 11. The tubular focusing electrode 6 and the external axial magnetic field further constrain the propagation range of the electron beam. Reference Figure 5 The horizontal axis represents the device height in mm, and the vertical axis represents the axial magnetic field strength in T. The axial magnetic field in the figure changes nonlinearly with the device height. Under the above simulation conditions, the electrons emitted by the array-type cold cathode assembly 3 first pass through the corresponding grid holes under the action of the electric field formed by the sinking grid 4, and then enter the electron beam transmission region formed by the tubular focusing electrode 6 and the external axial magnetic field. They are then transmitted along the axial direction towards the anode cylinder 11. Through the sequential action of the grid electric field, the tubular focusing electrode 6 and the external axial magnetic field, the electron beam can be focused and compressed at the same time as the electron extraction is completed, providing conditions for obtaining a more concentrated output electron beam. Under the specific parameter combination mentioned above, the existing simulation results show that the electron throughput is about 100%, and the electron beam with a cathode emission area of ​​28.3 mm² has an output cross-sectional area of ​​1.5 mm² after compression. The electron beam cross-sectional area compression ratio is about 18. The simulation results are used to illustrate that electron transport and electron beam compression effects can be achieved under the specific structural dimensions, potential and magnetic field conditions mentioned above. They do not constitute a limitation on other structural dimensions, potential parameters or magnetic field parameters. In summary, this embodiment uses the positioning protrusion on the outer periphery of the cathode substrate 1 as the main assembly reference. The slotted insulating connector 2 is fitted with the cathode substrate 1 through the corresponding positioning slot. The sunken grid 4 is supported by the stepped surface on the upper part of the slotted insulating connector 2. The sliding ring 7 is fitted with the same positioning protrusion through the inner groove and abuts against the slotted insulating connector 2 from below. This makes the array-type cold cathode assembly 3, the sunken grid 4 and the axial adjustment structure form an interconnected positioning chain. Through this structural relationship, the operational complexity caused by adjusting the position of the cathode array and the grid separately in the traditional assembly process can be reduced, the alignment consistency between the grid hole and the cold cathode unit can be improved, and the axial position of the sunken grid 4 can be easily adjusted. At the same time, the insulating ring 5, the tubular focusing electrode 6, the segmented sleeve and the anode cylinder 11 form a complete electron emission, grid control, focusing and transmission structure.

[0033] Example 2: This embodiment provides a method for fabricating an easy-to-assemble grid-controlled array type cold cathode electron gun, which specifically includes the following steps: S1. A cathode substrate 1 with a columnar structure and raised positioning blocks around its perimeter is fabricated; S2. A groove-shaped insulating connector 2 with a double-step columnar structure in the internal cavity and grooves around the inside is processed and then precisely engaged with the protruding positioning block of the cathode substrate 1. S3. A cold cathode array 3 consisting of several rectangular blocks arranged in an array is obtained, and cold cathode material is planted on the upper surface; S4. A recessed grid 4 with a number of grid holes is processed and then the non-perforated area of ​​the lower surface of the recessed grid 4 is fixed to the upper stepped surface of the groove-shaped insulating connector 2. S5. An insulating ring 5 is fabricated, and then the lower surface of the insulating ring 5 is fixed to the upper surface of the sunken grid 4; S6. The tubular cluster electrode 6 is processed and then the lower surface of the tubular cluster electrode 6 is fixed to the upper surface of the insulating ring 5. Finally, the slotted insulating connector 2, the sunken grid 4, the insulating ring 5 and the tubular cluster electrode 6 are fixedly connected by screws. S7. A sliding ring 7 with a ring-shaped structure and grooves around the inside of the ring is processed and then pushed upward to be flush with the bottom of the cathode substrate 1, so that the sinking grid 4 moves upward to the desired working position. S8. A cathode base 8 with a double-stepped truncated column structure is fabricated, and then the cathode base 8 is welded to the lower surface of the cathode substrate 1. S9. The lower sleeve 901, middle sleeve 902, upper sleeve 903, annular grid electrode 1001 and annular cluster electrode 1002 are processed and then sequentially sealed and connected to the cathode base 8, the lower sleeve 901, the annular grid electrode 1001, the middle sleeve 902, the annular cluster electrode 1002 and the upper sleeve 903, and the lower annular edge region of the sunken grid 4 is welded to the upper surface of the annular grid electrode 1001, and the upper annular edge region of the tubular cluster electrode 6 is welded to the lower surface of the annular cluster electrode 1002. S10. Seal the upper port of the upper sleeve 903; S11. Create a vacuum inside the insulating shell of the electron gun by pumping air.

[0034] It should be noted that in step S3, the array-type cold cathode 3 is fabricated according to the following steps: S301. Using wire cutting technology, grooves are cut and holes are made on the upper surface of the cathode substrate 1 to obtain an array-type cold cathode 3 with a groove depth between 0.1 and 0.3 mm.

[0035] Further, in step S4, the sunken grid 4 is processed according to the following steps: S401. A slicing process is used to obtain metal sheets with a thickness between 0.04 and 0.08 mm; S402. Using laser etching, the central region of the metal sheet is drilled and etched to obtain several grid holes arranged in an array in the sunken grid 4. Thus, the aforementioned easy-to-assemble, high-alignment grid-controlled array cold cathode electron gun can be easily fabricated using the simple process described in steps S1 to S11.

[0036] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of this application. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this application. Various changes and modifications can be made to this application without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of the claims of this application.

Claims

1. A grid-controlled array type cold cathode electron gun that is easy to assemble, characterized in that, Includes a cathode substrate (1), an array of cold cathode components (3) is disposed on the upper part of the cathode substrate (1), and positioning protrusions are disposed on the outer periphery of the cathode substrate (1); The cathode substrate (1) is fitted with a groove-shaped insulating connector (2) on its outer periphery. The inner side of the groove-shaped insulating connector (2) is provided with a positioning groove that matches the positioning protrusion. The upper part of the groove-shaped insulating connector (2) is provided with a stepped surface. A sunken grid (4) is installed on the stepped surface. The sunken grid (4) is provided with a plurality of grid holes, which are arranged opposite to the array-type cold cathode assembly (3). A slidable ring (7) is fitted around the outer periphery of the cathode substrate (1). The upper part of the slidable ring (7) abuts against the lower part of the groove-shaped insulating connector (2), and a groove that matches the positioning protrusion is formed on the inner side of the slidable ring (7).

2. The easily assembled grid-controlled array type cold cathode electron gun according to claim 1, characterized in that, The positioning protrusions are provided in multiple ways, and the multiple positioning protrusions are arranged at equal intervals along the outer periphery of the cathode substrate (1). The positioning grooves are provided in multiple ways, and each of them corresponds to and cooperates with the multiple positioning protrusions.

3. The easily assembled grid-controlled array type cold cathode electron gun according to claim 1, characterized in that, The groove-shaped insulating connector (2) has an internal cavity sleeved on the outer periphery of the cathode substrate (1). The internal cavity has a columnar structure, and the stepped surface is formed on the upper part of the internal cavity.

4. The easily assembled grid-controlled array type cold cathode electron gun according to claim 1, characterized in that, The array-type cold cathode assembly (3) includes multiple cold cathode units arranged in an array. Each cold cathode unit is rectangular in shape. Multiple grid holes correspond to the shape and size of the multiple cold cathode units, and the center of each grid hole is aligned with the center of the corresponding cold cathode unit.

5. A grid-controlled array type cold cathode electron gun that is easy to assemble according to claim 2, characterized in that: The slidable ring (7) is coaxially arranged with the cathode substrate (1). The slidable ring (7) has multiple grooves, which are arranged at equal intervals along the inner circumference of the slidable ring (7) and correspond to and cooperate with multiple positioning protrusions.

6. The easily assembled grid-controlled array type cold cathode electron gun according to claim 3, characterized in that: The sunken grid (4) has a sheet-like structure, with multiple grid holes set in the middle region of the sunken grid (4), and the non-perforated area of ​​the sunken grid (4) surrounding the multiple grid holes is in contact with the stepped surface; An insulating ring (5) is provided on the side of the sunken grid (4) away from the groove-shaped insulating connector (2), and a tubular gathering pole (6) is provided on the side of the insulating ring (5) away from the sunken grid (4).

7. A grid-controlled array type cold cathode electron gun that is easy to assemble according to claim 6, characterized in that: The groove-shaped insulating connector (2), the sunken grid (4), the insulating ring (5), and the tubular gathering pole (6) are stacked sequentially from bottom to top. Threaded holes are provided at corresponding positions on the groove-shaped insulating connector (2), the insulating ring (5), and the tubular gathering pole (6). A connecting hole corresponding to the threaded hole is provided on the sunken grid (4). The groove-shaped insulating connector (2), the sunken grid (4), the insulating ring (5), and the tubular gathering pole (6) are fixed by screws. The screws pass through the connecting holes and are threadedly connected to the threaded holes.

8. A grid-controlled array type cold cathode electron gun that is easy to assemble according to claim 7, characterized in that: A cathode base (8) is installed on the lower part of the cathode substrate (1). The cathode base (8) has a columnar structure and a stepped surface is provided on the outer edge of the cathode base (8).

9. A grid-controlled array type cold cathode electron gun that is easy to assemble according to claim 8, characterized in that: An insulating shell assembly is fixedly installed on the stepped surface of the cathode base (8). The insulating shell assembly includes a lower sleeve (901), a middle sleeve (902), and an upper sleeve (903) arranged sequentially along the axial direction. The cathode base (8) is sealed to the lower part of the lower sleeve (901).

10. A grid-controlled array type cold cathode electron gun that is easy to assemble according to claim 9, characterized in that: An annular grid sheet (1001) is installed between the lower sleeve (901) and the middle sleeve (902), and the annular grid sheet (1001) abuts against the edge area of ​​the recessed grid (4); An annular focusing electrode (1002) is installed between the middle sleeve (902) and the upper sleeve (903), and the annular focusing electrode (1002) abuts against the edge region of the tubular focusing electrode (6).

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