KR20100123987A - Cold cathode field emission device and x-ray generation apparatus using it - Google Patents

Abstract

PURPOSE: A cold cathode rotation field emission device and an X-ray generator using the same are provided to replace a cathode several times by concentrically arranging a nano emitter array on a circular plate. CONSTITUTION: A substrate(110) forms an emitter array for emitting electrons. A gate electrode(120) is mounted to face a substrate. The gate electrode is adjacently integrated with the emitter array and has an electron inducing unit(121) combined by a combining unit. An X-ray is generated by emitting the electrons to both targets via the electron inducing unit.

Description

Cold Cathode Field Emission Device and X-ray Generation Apparatus Using It {Cold Cathode Field Emission Device and X-ray Generation Apparatus using it}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a field emission device, and in particular, an array of nano-emitters arranged concentrically on a circular substrate as an electron emitter that emits an electron beam on a quantum mechanical field emission principle. And the electron beam is emitted by using the nano-emitter group near the electron induction portion of the gate electrode as the cold cathode, and the circular substrate is removed when the nano-emitter group is no longer functional due to the end of the lifetime of the nano-emitter group. Rotate and replace the cathode with an adjacent group of nano-emitters that can be used as an electron emitter for a long time without the need to reattach the cathode, or for the time required to operate the device, e.g. for X-ray tube generation X-ray generation by rotating the nano-emitter cathode during the time (X-ray generation time + cathode start time + cathode stop time) (Or electron-emitting time) relates to each of the times that the nano-meter can reduce the time that contributes to electron emission to increase the life of the negative electrode unit type field emission device and the X-ray generating apparatus using the same for.

Recently, the development of electron emission sources for electron beam emission is a major issue to improve the performance of X-ray generation in the medical field, such as diagnosis and treatment, and industrial fields such as non-destructive testing.

In general, the filament-based and carbon nanotube-based electron emission source has a complex and inefficient structure or a short life of the cathode portion has been a lot of research to solve this problem.

 For example, the conventional tungsten filament type hot electron emission source has to apply a current to both ends of the filament of the cathode to emit a desired amount of electrons to make the filament hot, and to accelerate the anode toward the anode or cathode side. A high voltage is required, and even in a conventional carbon nanotube-based electron emission source, a high voltage needs to be applied to the anode or the cathode in the process of emitting electrons to accelerate X-rays and accelerating toward the anode. Due to the environment, there is a problem in that the life of the cathode portion is shortened due to the effects of electrical arcing, cathode back bombardment, etc., which increases the cost of replacing the X-ray device or the cathode portion.

Accordingly, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is that it is difficult to commercialize in industrial fields such as medical field and non-destructive inspection due to the short lifetime of the cathode part constituting the field emission device for electron emission. In order to overcome the problem, it is to provide a rotating field emission device that can be used as an electron emission source for a long time without remounting the cathode portion using a nano-emitter array and an X-ray generator using the same.

In addition, another object of the present invention is to form a nanometer array to be arranged concentrically on a circular substrate, to emit an electron beam using a group of nanometers in close proximity to the electron induction portion of the gate electrode as a cold cathode, the nano Rotating field emission device capable of obtaining a plurality of cathode replacement effects by rotating a circular substrate and replacing a cathode part with an adjacent nano-emitter group when the emitter group is no longer functioning due to the end of its life. An X-ray generator is provided.

In addition, another object of the present invention is to form a nano-emitter array arranged concentrically on a circular substrate, and to rotate the nano-emitter cathode for the time required for the operation of the device to rotate the nano-emitter in proximity to the electron inducing portion of the gate electrode It is to provide a rotating field emission device and an X-ray generator using the same that can obtain the effect of increasing the lifetime of the cathode part by emitting an electron beam in the meter group.

First, to summarize the features of the present invention, an X-ray generator according to an aspect of the present invention for achieving the above object, a substrate formed with an emitter array for electron emission; And a gate electrode mounted opposite to the substrate, the gate electrode having an electron induction part integrally formed closer to the emitter array than the other part or coupled by a fastening means; And an anode target, and emits electrons generated in a part of the emitter group in the emitter array facing the electron induction part based on the voltage difference between the substrate and the gate electrode through the electron induction part toward the anode target. X-rays can be generated.

When the lifetime of the emitter group ends, the substrate may be rotated to emit electrons using adjacent emitter groups among the emitter arrays.

This negative electrode replacement effect into adjacent groups of nano-emitters is characterized in that the emitter array is rotated at a constant speed during the time required for X-ray generation (X-ray generation time + cathode start time + cathode stop time). By generating electrons through the emitter group opposite to the electromagnetic induction unit continuously selected, it can also be achieved through the effect that each emitter group operates only for a part of the total operating time.

The X-ray generator further includes a rotating mechanism (not shown) for mounting the substrate on a predetermined axis to rotate the substrate. The substrate may be rotated using the rotation mechanism to select a group of emitters facing the electromagnetic induction part from the emitter array.

The substrate is rotated on the shaft or mounted on the table mounted on the shaft through a fastening means penetrating through the center of the substrate to rotate the shaft or to fix the shaft to the central portion of the shaft. The substrate or the table may be rotated.

Here, the shaft or the center portion can be rotated in direct connection with the rotary shaft of the external motor, or by adding a means for generating a DC or AC magnetic field around the shaft or the center portion is rotated as a rotor of the motor. The magnetic field generating means may serve as a stator of the motor.

 The X-ray generator includes a leakage current blocking electrode to which the same voltage as the substrate is applied between the substrate and the electromagnetic induction part, and emits the generated electrons within an opening of the leakage current blocking electrode. It is possible to prevent current flow to the edge portion of the electromagnetic induction part.

The substrate is a circular substrate, and the emitter array is formed in the form of a track or a disk of constant diameter in a range within two diameters in a concentric circle.

The X-ray generator includes a track-shaped second emitter array concentric with the track-shaped emitter array on the substrate, and penetrates electrons generated by some emitter groups in the second emitter array. And a second gate electrode having a second electron induction part for emitting the same, and may generate X-rays on different surfaces of the anode target according to application of voltage to the first gate electrode or the second gate electrode.

The X-ray generator further includes a second gate electrode having a second electron induction part for discharging electrons generated by another part of the emitter group in the emitter array at a position different from the gate electrode. As the voltage is applied to the first gate electrode or the second gate electrode, X-rays may be generated on different surfaces of the anode target.

The X-ray generator includes a track-type second emitter array concentric with the track-type emitter array on the substrate, and the electromagnetic induction part along a predetermined sliding guide using a mechanism coupled to the gate electrode. X-rays may be generated from the anode target by horizontally moving and emitting electrons generated in some emitter groups in the second emitter array through the moved electron induction part.

The emitter array is based on CNTs, graphene, nanofibers, nanorods, nanoneedles, or nanopins. It may be made of.

In addition, according to another aspect of the present invention, a rotatable field emission device includes: a substrate on which an emitter array for electron emission is formed; And a gate electrode mounted opposite to the substrate, the gate electrode having an electron induction portion integrally formed closer to the emitter array than the other portion or coupled by a fastening means, wherein the voltage difference between the substrate and the gate electrode is reduced. The electrons may be generated from an emitter group selected from the emitter arrays facing the electron induction unit, and may be emitted through the electron induction unit toward the anode target.

In addition, the X-ray generation method according to another aspect of the present invention, by applying a voltage between the substrate and the gate electrode on which the emitter array is formed, integrally closer to the emitter array than the rest of the gate electrode X-rays may be generated by emitting electrons from a part of the emitter group in the emitter array formed or opposed to the electron induction part coupled to the gate electrode by the fastening means to penetrate the electron induction part in a grid toward the anode target. have.

When the lifetime of the emitter group ends, the substrate may be rotated to emit electrons using adjacent emitter groups among the emitter arrays.

While rotating the substrate at a constant speed, electrons may be generated through an emitter group opposite to the electron induction unit continuously selected from the emitter array.

As described above, according to the rotatable field emission device and the X-ray generator using the same, the nano-emitter array is formed to be arranged concentrically on a circular substrate, and thus the life of the nano-emitter group, which has been partially used, When no longer functioning, the circular substrate is rotated to replace the cathode part with an adjacent nano-emitter group, thereby obtaining the effect of replacing the cathode part a plurality of times, thereby extending the service life for a long time without remounting the cathode part to be used as an electron emission source. Can be.

In addition, the nano-emitter array is formed to be arranged concentrically on the circular substrate, and by rotating the nano-emitter cathode for the time required for the operation of the device to emit an electron beam from the group of nano- emitters close to the electron induction portion of the gate electrode During the time required for X-ray generation (X-ray generation time + cathode start time + cathode stop time), the effect of increasing the lifetime of the cathode part can be obtained by reducing the time that each nanometer group contributes to electron emission. have.

Accordingly, in the industrial field such as the medical field and the non-destructive inspection, it is possible to facilitate the commercialization by using the X-ray generator to which the rotary field emission device of the present invention is applied.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view for explaining the basic concept of the rotatable field emission device 100 according to an embodiment of the present invention. Referring to FIG. 1, a rotatable field emission device 100 according to an embodiment of the present invention includes a gate having a substrate 110 and an electron induction part 121 on which a nano-emitter array NE is formed for electron emission. Electrode 120.

2 is a view for explaining the structure of the rotatable field emission device 200 using the rotating mechanism of another structure. Referring to FIG. 2, the rotatable field emission device 200 according to another embodiment of the present invention has a substrate 210 in which a nano emitter array NE for electron emission is formed similarly to the substrate 110 of FIG. 1. And the gate electrode 220 having the electron induction part 221 similarly to the gate electrode 120 of FIG. 1.

The structure of FIG. 1 and the structure of FIG. 2 are rotating mechanisms for mounting the substrate 110/210 on which the nano-emitter array NE is formed on a predetermined axis 112/212 and rotating the substrate 110/210. Only the structure of the structure is different.

The structure of FIG. 1 is a structure in which the substrate 110 is mounted at the center of the rotation shaft 112 through the fastening means 111 penetrating the center of the substrate 110. The substrate 110 is rotated by rotating the rotation shaft 112. This is a structure that can be rotated at the same time. At this time, in order to smoothly move the rotating shaft 112, it is preferable to rotate the rotating shaft 112 by installing a bearing around the rotating shaft 112. Although not shown in the drawing, the rotating shaft 112 has a predetermined adjustment in the form of a screw. The mechanism may be rotated manually, or may be electrically rotated using a rotational force of a predetermined electric device. In addition, although not shown in the drawings, the substrate 110 may be mounted on a predetermined table integrated with the rotating shaft 112, and at this time, the table 110 and the substrate 110 integrated with the rotating shaft 112 may be simultaneously mounted. It can also rotate.

2 is a structure in which the substrate 210 is mounted at the center of the shaft 212 through the fastening means 211 penetrating the central portion of the substrate 210. The substrate 2 is fixed with the shaft 212 fixed thereto. The central portion of the 210 is rotated so that only the substrate 210 can rotate. In addition, although not shown in the drawings, the center 210 is mounted on the shaft 212 and the substrate 210 may be mounted on a predetermined table that rotates. In this case, the rotating table is rotated with the shaft 212 fixed. The substrate 210 can also be rotated. In this case, it is preferable to install a bearing under the substrate 210 or the table so that the substrate 210 or the table mounted on the shaft 212 moves smoothly, and although not shown in the drawing, the bearing is mounted on the shaft 212. The substrate 210 or the table may be rotated by manually operating a predetermined adjustment mechanism in the form of a screw, or may be electrically rotated using a rotational force of an electric device.

Here, in order to rotate the central portion of the substrate 210 mounted on the rotary shaft 112 or the shaft 212 or the corresponding table, although not shown in the drawing, the portion to be rotated is directly connected to the rotary shaft of the external motor. Alternatively, or by rotating the electric motor by applying a direct current (DC) or alternating current (AC) magnetic field around the portion to be rotated using the principle of rotation of the electric motor. For example, by adding a means for generating a DC or AC magnetic field around the rotating shaft 112, the rotating shaft 112 serves as a rotor of the motor, the above magnetic field generating means is a stator of the motor ( stator) role.

3 is a plan view of a circular substrate on which a nano emitter array NE is formed according to an embodiment of the present invention. As shown in FIG. 3, the nano-emitter array NE may be formed on a conductive circular substrate 110/210 in a track shape within a range of two diameters within a concentric circle. Here, although the nano-emitter array (NE) is illustrated in the form of a track in the range within the two diameters, it is not limited to this may also be a structure formed in the form of a disc of a certain diameter.

The electromagnetic induction part 121/221 having a grid shape (lattice structure) may be integrally formed closer to the nano emitter array NE than the rest of the gate electrode 120/220 as shown in FIG. 1 or 2. Or may be coupled to a corresponding portion of the gate electrode 120/220 in which a hole is formed by a predetermined fastening means.

In the structure of the rotatable field emission device 100/200, the substrate 110/210 is rotated by rotating the substrate 110/210 on the substrate 110/210 mounted in each rotating mechanism in a corresponding rotational movement manner. The emitter group opposed to the electron induction parts 121/221 may be selected from the nanoemitter arrays NE formed at the.

Since the electron induction parts 121 and 221 are located close to the nano emitter array NE, in the case of applying a predetermined voltage such as several volts to several kilo volts between the substrate 110/210 and the gate electrode, Electrons may be generated in the emitter group opposite to 121/221, and the generated electrons may be emitted through holes in the grid-shaped electron induction part 121/221.

As described above, when electrons are generated by the field emission principle using the emitter group as the cold cathode, the emitter group usually does not generate electrons any more after several hours to several tens of hours. In the emitter group, when the electrons are no longer generated as desired, the nano-emitter array formed on the substrate 110/210 by rotating the substrate 110/210 using the above-described rotation mechanism (NE) The emitter group adjacent to the emitter group used above may be positioned to face the electromagnetic induction part 121/221. Accordingly, it is possible to continuously maintain the generation of electrons in the adjacent emitter groups without reassembly or reassembly of the substrate 110/210 used as the cathode part, thereby reducing the cost of replacing the X-ray tube or the cathode part. It becomes possible.

Here, the nano-emitter array (NE) used as the electron emission source is a carbon nanotube (CNT), graphene (graphene), nano-fiber (nano-fiber), nano-rod (nano-rod), Nano-needle, or nano-pin based nanometers can be made.

For example, by spraying the carbon nanotube powder 2 to 3 times repeatedly using a spray gun on the front surface of the conductive metal substrate 110/210 by using a screen printing method, an appropriate amount of carbon nanotube is applied to the substrate. It can be applied on top. Alternatively, when fabricating carbon nanotubes through a chemical vapor deposition (CVD) method, a buffer layer such as TiN is coated on the metal substrate 110/210 as described above, and a catalytic material such as Ni or Fe is applied thereto. After the catalyst is applied, etching is performed with a gas such as argon or helium to form seed particles, and then a carbon nanotube source gas such as C ₂ H ₂ is injected to grow the carbon nanotubes. Can be.

Carbon nanotubes such as hexagonal crystal lattice consisting of six carbons are connected to each other to form a tubular shape, and the diameter of the tube is only tens to tens of nanometers. Since these carbon nanotubes are nanometers in diameter and can grow from tens of nanometers to tens of micrometers in length, the field enhancement factor, which is a parameter that determines the field emission ability of electrons, is more than 1000, compared to other materials. Since it is large, it has a structure that emits electrons much more easily than the method of extracting electrons by conventional electron emission from tungsten filament, and by using quantum mechanical field emission method to extract the same amount of electrons Relatively less power is consumed.

On the other hand, when rotating the substrate 110/210 to select the emitter group adjacent to the emitter group already used in the nano-emitter array (NE) to oppose the electromagnetic induction unit 121/221 to replace the cathode, The selected group of emitters opposed to the electromagnetic induction portions 121/221 is assumed to be trapezoidal as shown in FIG. Here, it is assumed that the average radius R _t of the emitter array track is very small as 16 mm. At this time, if the rotation angle θ at the time of replacing the cathode part is 3.6 degrees, R _t θ is 0.5 mm, and dR is 2 mm, the area of the emitter group opposite to the electromagnetic induction part 121/221 is 1 mm ² . Therefore, there is an effect of replacing the emitter group of 100 times to rotate 360 degrees, when the emitter with an area of 1mm ² is available for 100 hours, the life time of the overall cathode is increased to 10000 hours. Thus, in the present invention, by rotating the circular substrate (110/210) to replace the cathode portion with the adjacent nano-emitter group to obtain the effect of replacing the cathode portion multiple times, it can be used as an electron emission source by extending the life for a long time without remounting the cathode portion It becomes possible.

The effect of cathodic replacement to adjacent groups of nanoemitters is such that nanometers can be applied to the X-ray tube for the time required for X-ray generation (X-ray generation time + cathode start time + cathode stop time). It can be achieved by rotating the substrate 110/210 on which the array NE is formed. For example, during the rotation of the substrate 110/210, an electron beam from a group of nano emitters selectively adjacent to the electron induction part 121/221 among the nano-emitter arrays NE formed on the substrate 110/210. Can be released, and such a continuous selection of proximity nanometer groups can be made continuously while rotating the substrate 110/210. At this time, the group of nanometers facing the electron induction part 121/221 is changed continuously in time, so that each nanometer group reduces the time that contributes to the electron emission, so that each nanometer is totally As a result, it operates only for a part of the time, thereby increasing the lifetime of the entire cathode portion. At this time, it is preferable that the substrate 110/210 maintains a constant speed depending on an appropriate rotational speed, for example, one rotation per minute, two rotations, ..., etc. during the time required for X-ray generation.

Hereinafter, referring to the drawings of FIGS. 5 to 15, the rotary field emission device having the basic structure as described above may be mounted, and X-rays may be generated through the anode target by electrons generated from the rotational field emission device. An X-ray generator of various structures according to the present invention is described. Here, the rotatable field emission element and the anode target may be mounted in a housing made of an insulating material (see 131 in FIG. 5), and the space inside the housing 131 may be vacuumed by a predetermined vacuum exhaust sealing process. It is noted that the vacuum can be made or maintained by any vacuum pump. Further, hereinafter, the substrate 110/310/410/510 formed with the nano-emitter array NE is rotatable with the structure of FIG. 1 or 2, and the substrate 110/310/410/510 is replaced by itself. For this purpose, the rotating shaft 112 of FIG. 1 or the shaft 212 of FIG. 2 may be moved out of the housing 131 in a vacuum state by a predetermined rotating shaft moving device. As a method of moving the rotating shaft 112 of FIG. 1 or the shaft 212 of FIG. 2, a screw method, a method using a rack and pinion, or a method using a rotational force of a motor may be used.

5 is an example of an X-ray generator to which the rotary field emission device according to the present invention is applied. FIG. 6 is a plan view of a portion of the rotatable field emission device of FIG. 5.

As shown in FIG. 5 or 6, the gate 120 of the field emission device mounted in the housing 131 may receive a high voltage through a feed through, and thus, in the nano-emitter array NE The emitted electrons may collide with one surface of the anode target 130 to generate X-rays to emit X-rays to the outside through a predetermined window installed on one wall of the housing 131.

Here, in particular, as illustrated in FIG. 5 or 6, the leakage current blocking electrode 140 may be included between the substrate 120 and the electromagnetic induction part 121. A voltage equal to the substrate 120 may be applied to the leakage current blocking electrode 140, and may have a square or circular opening shape to prevent current flow to an edge portion of the electromagnetic induction part 121 as shown in FIG. 7. have. When the size of the opening of the leakage current blocking electrode 140 is made smaller than the portion of the electron passage of the electron induction part 121, as shown in FIG. 8, the emitted electrons from the nano-emitter array NE are the electron induction part 121. It becomes difficult to get to the edge of the conductor portion. However, when the leakage current blocking electrode 140 is not used as shown in FIG. 9, some of the electrons emitted from the nano-emitter array NE are directed to the edge conductor portion of the electron induction part 121, which causes leakage. As a cause of current, not only power loss but also adversely affect the X-ray quality. Therefore, in order to prevent leakage current flow to the edge conductor portion of the electromagnetic induction part 121, it is preferable to apply the leakage current blocking electrode 140.

10 is another example of the X-ray generator 300 to which the rotatable field emission device according to the present invention is applied. FIG. 11 is a plan view of a portion of the rotatable field emission device of FIG. 10.

Referring to FIG. 10 or 11, another X-ray generator 300 according to the present invention includes a first nano emitter array NE formed on the substrate 310, a gate electrode 320 and a substrate opposite thereto. And a second nanometer array NE formed on 310 and a gate electrode 350 opposite thereto, wherein the first nanometer array NE and the second nanometer array NE are each tracked. It is formed in the form and may be formed in the same concentric form. Here, the leakage current blocking electrode 340 may be included between the substrate 310 and each of the electromagnetic induction parts 321/351, and the same voltage as that of the substrate 310 is applied to the leakage current blocking electrode 340. Can be.

Electrons emitted from the first nano-emitter array NE pass through the corresponding openings of the leakage current blocking electrode 340 and pass through the electron induction part 321 of the gate electrode 320 to face one surface of the anode target 330. Electrons emitted from the second nano-emitter array NE penetrate the corresponding openings of the leakage current blocking electrode 340 and electron-inducing portions of the gate electrode 350. The X-ray B may be generated by colliding with the other surface of the anode target 330 by passing through 351. Here, X-ray A or B may be generated as shown in FIG. 12 according to whether the voltage is applied to the gate electrode 320 or the gate electrode 350. In some cases, the voltage may be applied to both of the gate electrode 320 or the gate electrode 350. It is also possible to generate X-rays A and B simultaneously. For example, X-ray A generated by colliding a large number of electrons on a surface having a large angle of the anode target 330 according to the high field emission current of the gate electrode 320 can be utilized as a large area image, and the gate electrode 350 X-ray B generated by colliding electrons to the surface of the anode target 350 is small according to the low field emission current of the) can be used as a small area image.

13 is another example of the X-ray generator 400 to which the rotatable field emission device according to the present invention is applied. FIG. 14 is a plan view of a portion of the rotatable field emission device of FIG. 13.

Referring to FIG. 13 or 14, another X-ray generator 400 according to the present invention includes one track-shaped nano-emitter array NE formed on the substrate 410 and both sides (left and right). Each gate electrode includes 420 and 450. Here, the leakage current blocking electrode 470 disposed between the substrate 410 and the electromagnetic induction part 321 and the leakage current blocking electrode 470 disposed between the substrate 410 and the electromagnetic induction part 451 may be included. The same voltage as that of the substrate 410 may be applied to the leakage current blocking electrodes 440 and 470.

Electrons emitted from the left part of the emitter group of the nano-emitter array NE pass through the corresponding opening of the leakage current blocking electrode 440 and pass through the electron induction part 421 of the gate electrode 420 to form the anode target 430. And X-rays may be generated by colliding with one side of the left side, and electrons emitted from some emitter groups on the right side of the nano-emitter array NE pass through the corresponding opening of the leakage current blocking electrode 470, and the gate X-rays may be generated by passing through the electromagnetic induction part 451 of the electrode 450 and colliding with the other right side of the anode target 430. Here, X-rays may be generated on the left or right side of the anode target 430 depending on whether the voltage is applied to the gate electrode 420 or the gate electrode 450, and in both cases, It is also possible to generate X-rays simultaneously on both the left and right sides of the anode target 430 by applying a voltage.

15 is another example of the X-ray generator 500 to which the rotatable field emission device according to the present invention is applied.

Referring to FIG. 15, another X-ray generator 500 according to the present invention includes a gate electrode 520 and a leakage current blocking electrode 540 similar to FIG. 1. However, in the case where two nano-emitter arrays NE are formed in a track shape on the substrate 510, even if only one gate electrode 520 is used, the apparatus 560 is adjusted to adjust a predetermined sliding guide. By allowing the electromagnetic induction part 521 to be moved horizontally, X-rays can be generated at different positions as shown in FIG. 10 or 13.

For example, adjusting the screw-shaped instrument 560 allows the electromagnetic guide 521 to move horizontally along the sliding guide to position either the outer or inner concentric tracks of the emitter array NE. have. Accordingly, at any position of the first nano emitter array NE outside the concentric circle or the second nano emitter array NE inside the concentric circle, the electrons emitted from the emitter group may leak the leakage current blocking electrode 540. X-rays may be generated by penetrating the corresponding opening of the gate electrode 520 and passing through the electron induction part 521 of the gate electrode 520 to collide with one surface of the anode target 530.

As described above, optimal embodiments have been disclosed in the drawings and the specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not intended to limit the scope of the present invention as defined in the claims or the claims. For example, although the embodiments of the above-mentioned nano-emitters have been mentioned, the present invention is not limited thereto, and may also be manufactured and used in the form of Spindt-type emitter tips. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a view for explaining the basic concept of a rotatable field emission device according to an embodiment of the present invention.

2 is a view for explaining a rotating mechanism of another structure.

3 is a plan view of a circular substrate on which a nano emitter is formed according to an embodiment of the present invention.

4 is a diagram illustrating a track type emitter array structure according to an embodiment of the present invention.

5 is an example of an X-ray generator to which the rotary field emission device according to the present invention is applied.

FIG. 6 is a plan view of a portion of the rotatable field emission device of FIG. 5.

FIG. 7 is a plan view illustrating the leakage current blocking electrode of FIG. 5.

FIG. 8 is an enlarged view of a portion A of FIG. 5.

9 is a view for explaining a leakage current when there is no leakage current blocking electrode.

10 is another example of the X-ray generator to which the rotary field emission device according to the present invention is applied.

FIG. 11 is a plan view of a portion of the rotatable field emission device of FIG. 10.

FIG. 12 is a diagram for explaining X-ray emission from the anode target of FIG. 10.

13 is another example of the X-ray generator to which the rotational field emission device according to the present invention is applied.

FIG. 14 is a plan view of a portion of the rotatable field emission device of FIG. 13.

15 is another example of the X-ray generator to which the rotational field emission device according to the present invention is applied.

Claims (23)

A substrate forming an emitter array for electron emission; A gate electrode mounted opposite the substrate, the gate electrode having an electron induction part integrally formed closer to the emitter array than the other part or coupled by a fastening means; And Including the anode target, Based on the voltage difference between the substrate and the gate electrode, electrons generated in a group of emitters in the emitter array facing the electron induction part are emitted through the electron induction part toward the anode target to generate X-rays X-ray generator characterized in. The method of claim 1, And when the lifetime of the emitter group ends, the substrate is rotated to emit electrons using adjacent emitter groups in the emitter array. The method of claim 1, And generating electrons through an emitter group opposed to the electromagnetic induction unit continuously selected from the emitter arrays while rotating the substrate at a constant speed. The method of claim 1, Rotation mechanism for mounting the substrate on a predetermined axis to rotate the substrate X-ray generator, characterized in that it further comprises. The method of claim 4, wherein And the emitter group opposing the electromagnetic induction part from the emitter array by rotating the substrate using the rotation mechanism. The method of claim 4, wherein The substrate is rotated on the shaft or mounted on the table mounted on the shaft through a fastening means penetrating through the center of the substrate to rotate the shaft or to fix the shaft to the central portion of the shaft. X-ray generator, characterized in that for rotating the substrate or the table. The method of claim 6, The shaft or the central portion is rotated in direct connection with the rotary shaft of the external motor, And a stator means for generating a DC or AC magnetic field around the shaft or central portion, such that the shaft or central portion is rotated as a rotor. The method of claim 1, A leakage current blocking electrode applied with the same voltage as the substrate between the substrate and the electromagnetic induction part, X-ray generator, characterized in that to prevent the current flow to the edge portion of the electromagnetic induction part by emitting the generated electrons within the opening of the leakage current blocking electrode. The method of claim 1, And said substrate is a circular substrate, wherein said emitter array is formed in the form of a track in the range of two diameters within concentric circles or in the form of a disk of constant diameter. The method of claim 1, A second emitter array in track form concentric with the emitter array in track form on the substrate, And a second gate electrode having a second electron induction part for releasing through electrons generated in some emitter groups in the second emitter array, The X-ray generator of claim 1, wherein the X-rays are generated on different surfaces of the anode target according to the voltage applied to the first gate electrode or the second gate electrode. The method of claim 1, And a second gate electrode having a second electron inducing part for releasing through electrons generated in another part of the emitter group in the emitter array at a position different from the gate electrode, The X-ray generator of claim 1, wherein the X-rays are generated on different surfaces of the anode target according to the voltage applied to the first gate electrode or the second gate electrode. The method of claim 1, A second emitter array in track form concentric with the emitter array in track form on the substrate, By moving the electromagnetic induction unit horizontally along a sliding guide using a mechanism coupled to the gate electrode, And generating an X-ray from the anode target by emitting electrons generated in a part of the emitter group in the second emitter array through the moved electron induction part. The method of claim 1, The emitter array is based on CNTs, graphene, nanofibers, nanorods, nanoneedles, or nanopins. X-ray generator, characterized in that consisting of. A substrate forming an emitter array for electron emission; And A gate electrode mounted opposite the substrate, the gate electrode having an electron induction portion integrally formed or coupled by a fastening means closer to the emitter array than the other portions, Field emission based on a voltage difference between the substrate and the gate electrode, generating electrons from an emitter group selected from the emitter array facing the electron induction part and emitting the electrons through the electron induction part toward an anode target device. The method of claim 14, Rotation mechanism for mounting the substrate on a predetermined axis to rotate the substrate The field emission device further comprises. The method of claim 14, A leakage current blocking electrode applied with the same voltage as the substrate between the substrate and the electromagnetic induction part, And emits the generated electrons within the opening of the leakage current blocking electrode to prevent current flow to the edge portion of the electromagnetic induction part. The method of claim 14, And said substrate is a circular substrate, wherein said emitter array is formed in the form of a track in the range of two diameters within concentric circles or in the form of a disk of constant diameter. The method of claim 14, A second emitter array in track form concentric with the emitter array in track form on the substrate, And a second gate electrode having a second electron induction part for releasing through electrons generated in some emitter groups in the second emitter array, And generating electrons from a group of emitters of a corresponding track selectively in response to the application of a voltage to the first gate electrode or the second gate electrode. The method of claim 14, And a second gate electrode having a second electron inducing part for releasing through electrons generated in another part of the emitter group in the emitter array at a position different from the gate electrode, And generating electrons from a group of emitters selectively according to the application of voltage to the first gate electrode or the second gate electrode. The method of claim 14, A second emitter array in track form concentric with the emitter array in track form on the substrate, By moving the electromagnetic induction unit horizontally along a sliding guide using a mechanism coupled to the gate electrode, And emit electrons generated in a part of the emitter group in the second emitter array through the moved electron induction part. A voltage is applied between the substrate and the gate electrode on which the emitter array is formed, Electrons generated in some emitter groups in the emitter array formed integrally with the emitter array closer to the emitter array than the rest of the gate electrode or opposed to the electron inducing portion coupled to the gate electrode by a fastening means are grid-shaped. X-ray generation method characterized in that the X-rays are generated by passing through the electromagnetic induction portion of the positive electrode target. The method of claim 21, And discharging electrons using adjacent emitter groups in the emitter array by rotating the substrate when the emitter group reaches the end of its life. The method of claim 21, And generating electrons through a group of emitters opposed to the electromagnetic induction unit continuously selected from the emitter arrays while rotating the substrate at a constant speed.

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