CN115529710B - Electronic curtain accelerator - Google Patents
Electronic curtain accelerator Download PDFInfo
- Publication number
- CN115529710B CN115529710B CN202211191741.3A CN202211191741A CN115529710B CN 115529710 B CN115529710 B CN 115529710B CN 202211191741 A CN202211191741 A CN 202211191741A CN 115529710 B CN115529710 B CN 115529710B
- Authority
- CN
- China
- Prior art keywords
- magnetic pole
- electron
- magnet
- beam spot
- dimensional
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000010894 electron beam technology Methods 0.000 claims abstract description 90
- 238000012545 processing Methods 0.000 claims abstract description 39
- 238000000265 homogenisation Methods 0.000 claims abstract description 9
- 238000004891 communication Methods 0.000 claims abstract description 5
- 238000004804 winding Methods 0.000 claims description 24
- 238000009826 distribution Methods 0.000 claims description 20
- 230000001133 acceleration Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 230000003287 optical effect Effects 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000001723 curing Methods 0.000 description 3
- 238000006477 desulfuration reaction Methods 0.000 description 3
- 230000023556 desulfurization Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000007665 sagging Methods 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- 229910052719 titanium Inorganic materials 0.000 description 3
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003546 flue gas Substances 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000001678 irradiating effect Effects 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 238000007639 printing Methods 0.000 description 2
- 238000003847 radiation curing Methods 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 238000009827 uniform distribution Methods 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 238000004043 dyeing Methods 0.000 description 1
- 238000001227 electron beam curing Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
- H05H7/00—Details of devices of the types covered by groups H05H9/00, H05H11/00, H05H13/00
- H05H7/001—Arrangements for beam delivery or irradiation
Abstract
The application relates to the technical field of electron acceleration, and provides an electron curtain accelerator, which comprises an electron gun, a beam spot processing device and a focusing device, wherein the electron gun comprises a cathode, the cathode is provided with an emission surface for emitting electron beam, and the electron beam is transmitted along the Z direction; the beam spot processing device is communicated with the electron gun and is used for carrying out beam spot expansion and homogenization on the electron beam; the focusing device is positioned downstream of the beam spot handling device in the Z-direction, the focusing device being in communication with the beam spot handling device, the focusing device being configured to operate the electron beam stream as a converging beam or a parallel beam to irradiate the object. According to the electronic curtain, the beam spots are enlarged and shaped to be uniformly distributed through the beam spot processing device, the focusing operation is carried out on the electron beam through the focusing device, so that the cathode can emit the electron beam through the emitting surface, the electron beam is processed into the electronic curtain through the beam spot processing device and the focusing device, and the filament-shaped cathode is not needed to be adopted to realize the electronic curtain.
Description
Technical Field
The application relates to the technical field of electron acceleration, in particular to an electron curtain accelerator.
Background
The electron curtain accelerator has wide application in the fields of sterilization, flue gas desulfurization, denitration, radiation curing and the like of food and medical supplies. Radiation curing refers to curing of the print coat by electron beam current of an electron curtain accelerator. At present, ultraviolet rays or chemical methods are mostly adopted for curing the printing and dyeing coating. However, ultraviolet light does not cure some coating dyes, chemical curing has harmful chemical residues, and the problems described above do not exist with electron beam curing of printing coatings. The flue gas desulfurization and denitrification is to carry out desulfurization and denitrification on the coal-fired waste gas of a power plant, so that on one hand, the pollution problem can be solved, and on the other hand, chemical fertilizers can be produced, and the waste utilization is realized.
The electron energy output by the electron curtain accelerator is 80keV (kiloelectron volt) to 300keV, and the electron current intensity is tens to hundreds of milliamperes. In the related art, an electron gun of an electron curtain accelerator adopts filaments to emit electron beam current, and in order to realize the electron curtain beam, the electron gun needs to be designed into a single filament with a length of about 1 meter or a plurality of short filaments arranged side by side. The working temperature of the filament is 500-1000 ℃, and the filament sag is generated by the expansion of a single lamp filament caused by heating, so that a series of problems of an optical structure of electron beam and the like are changed. The problem of thermal expansion of the multiple short filaments, while light, requires a solution to the problem of uniformity of the current emitted by the multiple short filaments. The mechanical structure of the single filament or a plurality of short filaments is very complex, so that the difficulties of design, manufacture, installation and operation of the electron gun are very high, and the manufacturing, installation and operation stability of the electron gun are very difficult to meet the industrial operation requirements.
Disclosure of Invention
In view of the foregoing, it is desirable to provide an electron curtain accelerator that reduces the difficulty of manufacturing an electron gun.
To achieve the above object, an embodiment of the present application provides an electronic curtain accelerator, including:
an electron gun comprising a cathode having an emission surface for emitting a beam of electrons, the beam of electrons being transported in a Z direction;
the beam spot processing device is communicated with the electron gun and is used for carrying out beam spot expansion and homogenization on the electron beam;
and a focusing device positioned downstream of the beam spot processing device in the Z direction, the focusing device being in communication with the beam spot processing device, the focusing device being configured to operate the electron beam stream as a converging beam or a parallel beam to irradiate an object.
In some implementations, the focusing device is a one-dimensional focusing magnet.
In some embodiments, the one-dimensional focusing magnet comprises two strip-shaped iron cores which are respectively wound with a first coil, the two strip-shaped iron cores are arranged at intervals in parallel along the Y direction to form a flow passage, and the two strip-shaped iron cores are excited in the flow passage to generate a one-dimensional linear gradient magnetic field along the X direction, wherein the X direction, the Y direction and the Z direction are mutually perpendicular.
In some embodiments, the one-dimensional focusing magnet comprises two non-magnetic conductive fixing pieces, and the two non-magnetic conductive fixing pieces are respectively positioned at two ends of the two strip-shaped iron cores along the X direction so as to connect the ends of the two strip-shaped iron cores.
In some embodiments, the one-dimensional focusing magnet comprises two deflection units, the deflection units comprise a connecting body wound with a second coil and a magnetic pole pair with two magnetic poles, the two magnetic poles of the magnetic pole pair are arranged at intervals along the Y direction, the connecting body is connected with one ends of the two magnetic poles of the magnetic pole pair, the other ends of the two magnetic poles of the magnetic pole pair are deflection ends, a gap between the two deflection ends of the magnetic pole pair is a circulation channel, parallel surfaces of the deflection ends of the magnetic pole pair opposite along the Y direction are magnetic pole surfaces, the projection of the deflection ends on a projection surface perpendicular to the Z direction is rectangular, the projection of the deflection ends on the projection surface perpendicular to the Y direction is wedge-shaped, and the two magnetic pole pairs are symmetrically arranged at intervals along the X direction.
In some embodiments, the beam spot treatment apparatus comprises:
a first beam expanding magnet configured to expand a beam spot of the electron beam current in an X direction;
a one-dimensional homogenizing magnet located downstream of the first beam expanding magnet in the Z direction, the one-dimensional homogenizing magnet being configured to homogenize a beam spot of the electron beam current in the X direction.
In some embodiments, the beam spot treatment apparatus comprises:
and a second beam expanding magnet positioned downstream of the one-dimensional homogenizing magnet in the Z direction, the second beam expanding magnet being configured to expand a beam spot of the electron beam in the X direction.
In some embodiments, the first symmetry axis of the one-dimensional homogenizing magnet extends along the X direction and comprises a bare magnetic pole pair and two winding magnetic pole pairs, wherein the bare magnetic pole pair and the winding magnetic pole pair are respectively provided with two pole heads, the two winding magnetic pole pairs are respectively positioned at two sides of the bare magnetic pole pair along the X direction, no coil is arranged at the two pole heads of the bare magnetic pole pair and are symmetrically distributed along the first symmetry axis, and the two pole heads of the winding magnetic pole pair are respectively provided with a coil and are symmetrically distributed along the first symmetry axis; the magnetic field distribution curve of the magnetic field generated by the two winding magnetic pole pairs along the X direction is an odd function.
In some embodiments, the magnetic field distribution curve of the magnetic field generated by the two wound magnetic pole pairs along the X direction is a power exponent function, the power exponent of the power exponent function is between 1.8 and 2.2, and the power exponent is not a constant over the whole curve.
In some embodiments, the electron curtain accelerator comprises a vacuum tube and a vacuum box, the electron gun and the beam spot processing device are communicated through the vacuum tube, the vacuum box comprises a vacuum cavity, an inlet and an outlet, the inlet and the outlet are both communicated with the vacuum cavity, the inlet is communicated with an emergent opening of the beam spot processing device, the outlet is communicated with the focusing device, and the size of the vacuum cavity in the X direction is gradually increased from the inlet to the outlet.
According to the electron curtain accelerator provided by the embodiment of the application, on one hand, as the density of the electron beam emitted by the emission surface is Gaussian, namely the density of the electron beam is uneven and cannot be directly used for irradiating an object, the electron curtain accelerator enlarges beam spots and is shaped into uniform distribution through the beam spot processing device, namely the electron beam is enlarged and homogenized through the beam spot processing device, and the electron beam is focused through the focusing device, so that the cathode can emit the electron beam by adopting the emission surface to process the electron beam into an electron curtain through the beam spot processing device and the focusing device, and the electron curtain is realized without adopting a filament-shaped cathode. Compared with filament-shaped cathodes, the electron gun adopting the emission surface to emit electron beam can avoid the problems of filament sagging, changing the optical structure of the electron beam and poor consistency of a plurality of filaments, has simple structure and convenient assembly, and solves the defects of high development difficulty, poor operation reliability, short service life and the like of the electron gun of the electron curtain accelerator in the related technology. On the other hand, the parallel beams output by the focusing device have larger coverage area and uniform density distribution, and can irradiate objects. The converging beam output by the focusing device not only can realize synchronous irradiation of multiple surfaces of an object, such as three surfaces of a square object, but also can improve the dose uniformity along the direction of the incident object.
Drawings
FIG. 1 is a schematic diagram of an electronic curtain accelerator according to an embodiment of the present disclosure;
FIG. 2 is a schematic diagram of a focusing apparatus focusing an electron beam into parallel beams according to an embodiment of the present application;
FIG. 3 is a schematic diagram of a focusing apparatus focusing an electron beam into a focused beam according to an embodiment of the present application;
FIG. 4 is a schematic structural diagram of a first one-dimensional focusing magnet according to an embodiment of the present application;
FIG. 5 is a schematic diagram showing a two-dimensional magnetic field distribution of the first one-dimensional focusing magnet shown in FIG. 4;
FIG. 6 is a one-dimensional magnetic field distribution diagram of the first one-dimensional focusing magnet shown in FIG. 4;
FIG. 7 is a schematic diagram of a second one-dimensional focusing magnet according to an embodiment of the present application;
FIG. 8 is a schematic view of a beam envelope of an electron curtain accelerator according to an embodiment of the present application;
FIG. 9 is a schematic diagram of a partial structure of a one-dimensional homogenizing magnet in an embodiment of the present application;
FIG. 10 is a schematic view of beam spots at a one-dimensional homogenizing magnet after an electron beam stream is expanded by a first beam expanding magnet according to an embodiment of the present application;
FIG. 11 is a schematic view of a beam spot of an electron beam stream after one-dimensional expansion and one-dimensional homogenization by a beam spot treatment apparatus according to an embodiment of the present application;
fig. 12 is a schematic structural diagram of a quadrupole magnet according to an embodiment of the present application.
Description of the reference numerals
An electron gun 1;
a beam spot processing device 2; a first beam expanding magnet 21; a one-dimensional homogenizing magnet 22; a polar surface portion 22a; a constriction 22b; a bare pole pair 221; a pair of wound magnetic poles 222; a first wound pole pair 2221; a second wound pole pair 2222; a second beam expanding magnet 23; a head 23a; a neck 23b;
a focusing device 3; a bar-shaped iron core 31; a through-flow channel 31a; a first bobbin 32; a non-magnetically permeable anchor 33; a deflection unit 301; a second coil 3011; a connector 3012; a pole pair 3013; a deflector end 30131; a flow channel 30131a; a magnetic pole face 30131b;
a vacuum tube 4;
a vacuum box 5;
an object 1000;
Detailed Description
It should be noted that, in the case of no conflict, the embodiments and technical features in the embodiments may be combined with each other, and the detailed description in the specific embodiments should be interpreted as an explanation of the gist of the present application and should not be construed as undue limitation to the present application.
In the embodiments of the present application, the orientation or positional relationship is based on the orientation or positional relationship shown in fig. 1, and it should be understood that these orientation terms are merely for convenience of description and to simplify the description, and are not indicative or implying that the apparatus or elements being referred to must have a particular orientation, be configured and operated in a particular orientation, and therefore should not be construed as limiting the present application. The present application will now be described in further detail with reference to the accompanying drawings and specific examples.
Referring to fig. 1, an embodiment of the present application provides an electron curtain accelerator, which includes an electron gun 1, a beam spot processing device 2, and a focusing device 3.
The electron gun 1 comprises a cathode having an emission surface for emitting a beam of electrons, which is transported in the Z-direction. The plane perpendicular to the Z direction is taken as a projection plane, and the density of electron beam current emitted by the emission plane is approximately Gaussian distribution.
The projection of the emitting surface on the projection surface perpendicular to the Z direction is planar. Illustratively, the emitting surface may be a plane, a convex arc surface, a concave arc surface, or the like along the Z direction.
Referring to fig. 1 and 11, a beam spot processing apparatus 2 is in communication with an electron gun 1, and the beam spot processing apparatus 2 is configured to perform beam spot enlarging and homogenizing operations on an electron beam. Specifically, the beam spot processing apparatus 2 is configured to perform beam spot one-dimensional expansion and one-dimensional homogenization operations on an electron beam stream. In other words, the beam spot processing apparatus 2 is configured to perform beam spot expansion in the X direction and homogenization operation in the X direction on the electron beam stream. The beam spots of the electron beam current processed by the beam spot processing apparatus 2 are expanded and uniformly distributed in one-dimensional directions such as the X-direction.
With continued reference to fig. 1, the focusing device 3 is located downstream of the beam spot processing device 2 in the Z direction. That is, the focusing device 3 is located on the side of the beam spot processing device 2 remote from the electron gun 1. In the Z direction, the electron beam current passes through the beam spot processing apparatus 2 and then through the focusing apparatus 3.
The focusing device 3 is in communication with the beam spot processing device 2. In this way, the electron beam current processed by the beam spot processing apparatus 2 can enter the focusing apparatus 3.
Referring to fig. 2 and 3, the focusing apparatus 3 is configured to operate the electron beam as a converging beam or a parallel beam to irradiate the object 1000. That is, the focusing device 3 can refocus the electron beam stream subjected to the expansion and homogenization operation into a converging beam or a parallel beam. Specifically, the focusing device 3 is used for performing a beam spot one-dimensional focusing operation on the electron beam. In other words, the focusing device 3 is used for focusing the electron beam in the X direction. That is, the beam spot of the electron beam processed by the focusing device 3 is focused in a one-dimensional direction such as the X-direction.
In the related art, in order to make the electron beam present an electron curtain, a filament-shaped cathode is required to be adopted to emit the electron beam, and the filament-shaped cathode has the problems that the single lamp wire expands to generate the sagging of the filament, so that the optical structure of the electron beam is changed, the consistency of a plurality of filaments is poor, and the like.
According to the electron curtain accelerator provided by the embodiment of the application, on one hand, as the density of the electron beam emitted by the emission surface is Gaussian, namely the density of the electron beam is uneven and cannot be directly used for irradiating the object 1000, the electron curtain accelerator enlarges the beam spots and shapes the beam spots into uniform distribution through the beam spot processing device 2, namely the electron beam is enlarged and homogenized through the beam spot processing device 2, and the electron beam is focused through the focusing device 3, so that the cathode can emit the electron beam by adopting the emission surface to process the electron beam into the electron curtain through the beam spot processing device 2 and the focusing device 3, and the electron curtain is realized without adopting a filament-shaped cathode. Compared with a filament-shaped cathode, the electron gun 1 adopting the emission surface to emit electron beam not only can avoid the problems of filament sagging, changing the optical structure of the electron beam and poor consistency of a plurality of filaments, but also has simple structure and convenient assembly, and solves the defects of the electron curtain accelerator in the related art such as high development difficulty, poor operation reliability, short service life and the like. On the other hand, the parallel beam output from the focusing device 3 has a large coverage area and uniform density distribution, and can irradiate the object 1000. The converging beam output from the focusing device 3 can not only realize synchronous irradiation of multiple surfaces of the object 1000, such as three surfaces of the square object 1000, but also improve dose uniformity along the direction of the incident object 1000.
The projection shape of the emission surface on the projection surface perpendicular to the Z direction is not limited, and exemplary projection shapes of the emission surface on the projection surface perpendicular to the Z direction include, but are not limited to, a circle. The density of the electron beam emitted by the round emission surface is closer to the gaussian distribution.
In some embodiments, the electron gun 1 is electrically connected with a high-voltage power supply, and the emission surface draws electron beam current under the action of the high-voltage power supply. The high-voltage power supply is used for supplying high-voltage power to the electron gun 1 so as to lead out high-energy high-current strong electron beam current.
In some embodiments, the current intensity of the electron beam current is not limited, and the electron beam current may be a high-current electron beam current. In other words, the current of the electron beam is more than 10mA (milliamp). Illustratively, the current intensity of the electron beam is adjustable, with an adjustment range between 0.02A (ampere) and 1A (ampere).
In one embodiment, referring to fig. 4 and 7, the focusing device 3 is a one-dimensional focusing magnet. The one-dimensional focusing magnet is used for carrying out one-dimensional focusing operation on the beam spots of the electron beam. That is, the beam spot of the electron beam processed by the one-dimensional focusing magnet is focused in one-dimensional direction such as the X-direction.
In one embodiment, referring to fig. 4 to 6, the one-dimensional focusing magnet includes two bar cores 31 each wound with a first coil 32, and the two bar cores 31 are arranged at intervals in parallel along the Y direction to form a flow channel 31a. Specifically, the through-flow channel 31a is used to circulate electron beam current. The two bar cores 31 are excited in the flow channel 31a to generate a one-dimensional linear gradient magnetic field in the X direction, wherein the X direction, the Y direction, and the Z direction are perpendicular to each other. That is, the one-dimensional linear gradient magnetic field can focus the electron beam current flowing through the flow channel 31a in the X direction.
In one embodiment, referring to fig. 4, the one-dimensional focusing magnet includes two non-magnetic fixing members 33, and the two non-magnetic fixing members 33 are respectively located at two ends of the two bar cores 31 along the X direction so as to connect the ends of the two bar cores 31. That is, both ends of the two bar cores 31 in the X direction are fixed by the non-magnetic conductive fixing members 33, respectively. In this way, the relative positions of the two bar cores 31 are kept unchanged by the non-magnetically conductive fixing member 33.
The non-magnetic conductive fixing member 33 is a structure using a non-magnetic conductive material. Non-magnetically permeable materials include, but are not limited to, aluminum. The non-magnetic fixing member 33 has characteristics such as low magnetic permeability. The non-magnetically permeable anchor 33 is generally not magnetized. In this way, the non-magnetically permeable fixture 33 is prevented from affecting the magnetic field distribution in the flow channel 31a.
In one embodiment, referring to fig. 7, the one-dimensional focusing magnet includes two deflection units 301, the deflection units 301 include a connection body 3012 around which a second coil 3011 is wound and a magnetic pole pair 3013 having two magnetic poles, the two magnetic poles of the magnetic pole pair 3013 are spaced apart along the Y direction, the connection body 3012 is connected to one end of the two magnetic poles of the magnetic pole pair 3013, and the other end of the two magnetic poles of the magnetic pole pair 3013 is a deflection end 30131. The deflecting end 30131 is the end of the pole away from the connector 3012. The gap between the two deflection ends 30131 of the pole pair 3013 is the flow channel 30131a.
The parallel surfaces of the deflection ends 30131 of the magnetic pole pairs 3013, which are opposite along the Y direction, are magnetic pole surfaces 30131b, the projection of the deflection ends 30131 on a projection surface perpendicular to the Z direction is rectangular, the projection of the deflection ends 30131 on a projection surface perpendicular to the Y direction is wedge-shaped, and the two magnetic pole pairs 3013 are symmetrically arranged at intervals along the X direction. That is, the deflection ends 30131 of the two pole pairs 3013 are spaced apart in the X-direction, and the deflection ends 30131 of the two pole pairs 3013 do not contact. The pole face 30131b is wedge-shaped.
The flow channel 30131a is used for flowing electron beam. That is, the electron beam passes between the two magnetic pole faces 30131b of the magnetic pole pair 3013, the magnetic field in the flow channel 30131a does not change much in the X direction, but the magnetic field areas through which electrons located at different positions of the flow channel 30131a pass are different in size, so that electrons away from the central axis receive a larger deflection force than electrons close to the central axis, thereby achieving one-dimensional focusing.
The wedge shape means that the dimension of the magnetic pole surface 30131b in the Z direction gradually increases from the direction closer to the central axis to the direction away from the central axis.
The connector 3012 is an iron yoke. Thus, the connector 3012 has good magnetic permeability.
The central axis extends in the Z direction and is located between the deflection ends 30131 of the two pole pairs 3013.
In one embodiment, referring to fig. 1 and 8, the beam spot processing apparatus 2 includes a first beam expanding magnet 21 and a one-dimensional homogenizing magnet 22.
The first beam expanding magnet 21 is configured to expand a beam spot of the electron beam current in the X direction. The beam spot of the electron beam passing through the first beam expander magnet 21 is substantially flat.
Illustratively, the first dimension of the beam spot of the electron beam current passing through the first beam expanding magnet 21 in the X direction is 5 times or more the second dimension in the Y direction. Thus, the beam is expanded along the X direction so as to enlarge the coverage area of the electron beam and meet the radiation range requirement.
The first dimension of the beam spot in the X-direction is much larger than the second dimension in the Y-direction. Illustratively, in one embodiment, referring to FIG. 10, the first dimension of the beam spot in the X-direction is between 50mm and 150 mm. For example, the first dimension of the beam spot in the X-direction is 50mm, 100mm, 110mm, 120mm, 150mm, etc. Referring to fig. 10, the beam spot has a dimension in the Y direction of between 5mm and 20 mm. For example, the first dimension of the beam spot in the X-direction is 5mm, 10mm, 20mm, etc.
With continued reference to fig. 1 and 8, a one-dimensional homogenizing magnet 22 is located downstream of the first beam expander magnet 21 in the Z direction. That is, the one-dimensional homogenizing magnet 22 is located between the first beam expanding magnet 21 and the focusing device 3. The electron beam from the emission surface passes through the first beam expanding magnet 21 and then passes through the one-dimensional homogenizing magnet 22.
The one-dimensional homogenizing magnet 22 is configured to homogenize a beam spot of the electron beam current in the X direction. The electrons of the electron beam flow are uniformly distributed in the X direction after being operated by the one-dimensional homogenizing magnet 22.
Illustratively, in one embodiment, the density distribution of the electron beam homogenized by the one-dimensional homogenizing magnet 22 is more than 10% non-uniformity in the X-direction. That is, the uniformity of the density distribution of the electron beam current homogenized by the one-dimensional homogenizing magnet 22 in the X direction is 10% or less.
In one embodiment, referring to fig. 1, 8 and 11, the beam spot processing apparatus 2 includes a second beam expanding magnet 23, and the second beam expanding magnet 23 is located downstream of the one-dimensional homogenizing magnet 22 in the Z direction. That is, the second beam expander magnet 23 is located between the one-dimensional homogenizing magnet 22 and the focusing device 3. The electron beam homogenized by the one-dimensional homogenizing magnet 22 is expanded by the second expanding magnet 23. The second beam expanding magnet 23 is configured to expand a beam spot of the electron beam current in the X direction. In this way, the third dimension of the beam spot of the electron beam current in the X direction is further enlarged by the second beam expanding magnet 23. On the other hand, the size of the beam spot of the electron beam in the X direction can be adjusted over a wide range by expanding the beam by the first beam expander magnet 21 and the second beam expander magnet 23, respectively. On the other hand, a one-dimensional homogenizing magnet 22 is provided between the first beam expanding magnet 21 and the second beam expanding magnet 23, and the density distribution uniformity of the electron beam current in the X direction is better.
For example, referring to FIG. 11, the third dimension of the beam spot in the X-direction is between 200mm and 1500 mm. Illustratively, in one embodiment, the third dimension of the beam spot in the X-direction is between 200mm and 1500 mm. For example, the third dimension of the beam spot in the X-direction is 200mm, 300mm, 500mm, 900mm or 1500mm, etc.
In an embodiment, referring to fig. 1 and 9, the one-dimensional homogenizing magnet 22 is in an axisymmetric pattern, a first symmetry axis extends along the X direction, and fig. 9 shows a half-sectional view of the one-dimensional homogenizing magnet with the first symmetry axis as a sectional line, where the one-dimensional homogenizing magnet includes a bare magnetic pole pair 221 and two winding magnetic pole pairs 222. The number of the wound pole pairs 222 is two, and the number of the bare pole pairs 221 is one. The bare pole pair 221 and the wound pole pair 222 each have two pole heads.
The two winding magnetic pole pairs 222 are respectively located at two sides of the bare magnetic pole pair 221 along the X direction, the two pole heads of the bare magnetic pole pair 221 are not provided with coils and are symmetrically distributed along the first symmetry axis, and the two pole heads of the winding magnetic pole pair 222 are provided with coils and are symmetrically distributed along the first symmetry axis.
Here, six pole heads of the one-dimensional homogenizing magnet are arranged in a circumferential direction around the central axis. The bare magnetic pole pair 221 is used for optimizing magnetic field distribution, and through the structural design of the bare magnetic pole pair 221 and the winding magnetic pole pair 222, the magnetic field formed by the one-dimensional homogenizing magnet can provide focusing effect for electrons along the X direction, so that the electron beam flowing through the one-dimensional homogenizing magnet can be uniformly distributed along the X direction.
It is understood that the first axis of symmetry intersects the central axis perpendicularly.
In one embodiment, referring to fig. 9, the arrows in fig. 9 schematically illustrate the magnetic field direction, and the magnetic fields generated by the two winding pole pairs 222 are opposite. In other words, one of the two winding pole pairs 222 is defined as a first winding pole pair 2221, and the other of the two winding pole pairs 222 is defined as a second winding pole pair 2222. The magnetic field direction of the first wound magnetic pole pair 2221 is opposite to the magnetic field direction of the second wound magnetic pole pair 2222. For example, the magnetic field direction of the first wound magnetic pole pair 2221 is upward in the Y direction, and the magnetic field direction of the second wound magnetic pole pair 2222 is downward in the Y direction.
It will be appreciated that the magnetic field generated between the pole tips may be varied by varying the excitation current in the coils of the one-dimensional homogenizing magnet.
The pole head of the one-dimensional homogenizing magnet is not limited in shape, and as shown in fig. 9, for example, the pole head of the wound pole pair 222 includes a pole face 22a and a constriction 22b, and the end face of the pole face 22a away from the constriction 22b is a pole face. The width of the projection of the constricted portion 22b is smaller than the width of the projection of the pole face portion 22a with a plane perpendicular to the Z direction as a projection plane. The projection of the pole head of the one-dimensional homogenizing magnet is approximately mushroom-shaped. Thus, the pole face of the pole face portion 22a can meet the requirement, and the width of the contraction portion 22b is smaller to facilitate winding the coil, and the pole face portion 22a can restrict the movement of the coil.
In one embodiment, the magnetic field distribution curve of the magnetic field generated by the two wound magnetic pole pairs 222 along the X direction is an odd function. That is, the magnetic field distribution curve of the magnetic field generated between the two pole heads of the two wound magnetic pole pairs 222 along the X direction is an odd function. Specifically, a plane perpendicular to the Z direction is taken as a projection plane, and the origin of coordinates of the odd function is located at the intersection point of the first symmetry axis and the central axis. In this way, the magnetic fields generated by the two winding magnetic pole pairs 222 are symmetrical about the origin of coordinates, and can provide a good homogenization effect for the beam spot of the electron beam.
In one embodiment, the magnetic field distribution curve of the magnetic field generated by the two winding pole pairs 222 along the X direction is a power exponent function. The exponentiation of the exponentiation function is between 1.8 and 2.2, the exponentiation is not a constant over the entire curve. That is, the exponentiation of the exponentiation function of the magnetic field distribution curve of the magnetic field generated between the two pole heads of the two described wound pole pairs 222 along the X-direction varies. Thus, the magnetic field gradient along the X-direction of the magnetic field generated by the two winding magnetic pole pairs 222 is moderate, so as to improve the uniformity of the beam spot of the electron beam.
In some embodiments, the power exponent may be adjusted based on the beam spot distribution density of the electron beam current. Thus, the one-dimensional homogenizing magnet can adapt to different densities.
In one embodiment, referring to fig. 10, the first beam expander magnet 21 and the second beam expander magnet 23 are quadrupole magnets. The quadrupole magnets are axisymmetric patterns.
In one embodiment, referring to fig. 10, the quadrupole magnet includes four pole heads each having a coil wound therearound, the pole heads of the quadrupole magnet include a head portion 23a and a neck portion 23b, and the end surface of the head portion 23a away from the neck portion 23b is a pole surface. The width of the projection of the neck 23b is smaller than the width of the projection of the head 23a with a plane perpendicular to the Z direction as a projection plane. The projection of the pole heads of the quadrupole magnets is approximately mushroom-shaped. Thus, the pole face of the head 23a can meet the requirement, the width of the neck 23b is small, the coil can be wound conveniently, and the head 23a can limit the movement of the coil.
In one embodiment, referring to fig. 1, the electron curtain accelerator includes a vacuum tube 4 and a vacuum box 5, the electron gun 1 and the beam spot processing apparatus 2 are communicated through the vacuum tube 4, the vacuum box 5 includes a vacuum chamber, an inlet and an outlet, the inlet and the outlet are all communicated with the vacuum chamber, the inlet is communicated with an exit port of the beam spot processing apparatus 2, the outlet is communicated with the focusing apparatus 3, and the size of the vacuum chamber in the X direction is gradually increased from the inlet to the outlet.
After the beam spot processing device 2 performs one-dimensional expansion and one-dimensional homogenization of the beam spot, the beam spot of the electron beam is gradually expanded in the X direction, so that the size of the vacuum cavity in the X direction is gradually increased from the inlet to the outlet, thereby facilitating the electron beam transmission.
For example, the projection shape of the vacuum chamber may be substantially fan-shaped with a plane perpendicular to the Y direction as a projection plane.
In one embodiment, the dimension of the vacuum chamber in the Y direction is uniform from the inlet to the outlet. That is, the size of the vacuum chamber in the Y direction remains unchanged.
It will be appreciated that the interior space of the vacuum tube 4 and the vacuum chamber are both in a vacuum state.
In one embodiment, the electron curtain accelerator includes a titanium film covering the outlet. The titanium film serves to isolate the vacuum chamber from the atmosphere so that the vacuum chamber is maintained in vacuum. The electron beam passes through the titanium film into the focusing device 3.
For example, in some embodiments, referring to fig. 1, the focusing device 3 may be spaced apart from the vacuum box 5 along the Z direction. In other embodiments, the focusing device 3 may be arranged in abutment with the vacuum box 5 in the Z-direction.
The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (6)
1. An electronic curtain accelerator, comprising:
an electron gun comprising a cathode having an emission surface for emitting a beam of electrons, the beam of electrons being transported in a Z direction;
the beam spot processing device is communicated with the electron gun and is used for carrying out beam spot expansion and homogenization on the electron beam;
a focusing device downstream of the beam spot processing device in the Z direction, the focusing device in communication with the beam spot processing device, the focusing device configured to operate the electron beam stream as a converging beam or a parallel beam to irradiate an object;
the focusing device is a one-dimensional focusing magnet, the one-dimensional focusing magnet comprises two deflection units, each deflection unit comprises a connecting body wound with a second coil and a magnetic pole pair with two magnetic poles, the two magnetic poles of each magnetic pole pair are arranged at intervals along the Y direction, the connecting body is connected with one ends of the two magnetic poles of each magnetic pole pair, the other ends of the two magnetic poles of each magnetic pole pair are deflection ends, a gap between the two deflection ends of each magnetic pole pair is a circulation channel, parallel surfaces of the deflection ends of each magnetic pole pair, which are opposite along the Y direction, are magnetic pole surfaces, the projection of the deflection ends on a projection surface perpendicular to the Z direction is rectangular, the projection of the deflection ends on the projection surface perpendicular to the Y direction is wedge-shaped, and the two magnetic pole pairs are symmetrically arranged along the X direction at intervals.
2. The electronic curtain accelerator according to claim 1, wherein the beam spot processing device comprises:
a first beam expanding magnet configured to expand a beam spot of the electron beam current in an X direction;
a one-dimensional homogenizing magnet located downstream of the first beam expanding magnet in the Z direction, the one-dimensional homogenizing magnet being configured to homogenize a beam spot of the electron beam current in the X direction.
3. The electronic curtain accelerator according to claim 2, wherein the beam spot processing device comprises:
and a second beam expanding magnet positioned downstream of the one-dimensional homogenizing magnet in the Z direction, the second beam expanding magnet being configured to expand a beam spot of the electron beam in the X direction.
4. The electronic curtain accelerator according to claim 2, wherein the first symmetry axis of the one-dimensional homogenizing magnet extends along the X direction and comprises a bare magnetic pole pair and two winding magnetic pole pairs, the bare magnetic pole pair and the winding magnetic pole pair each have two pole heads, the two winding magnetic pole pairs are respectively located at two sides of the bare magnetic pole pair along the X direction, no coil is arranged at the two pole heads of the bare magnetic pole pair and are symmetrically distributed along the first symmetry axis, and the two pole heads of the winding magnetic pole pair are respectively provided with a coil and are symmetrically distributed along the first symmetry axis; the magnetic field distribution curve of the magnetic field generated by the two winding magnetic pole pairs along the X direction is an odd function.
5. The electronic curtain accelerator of claim 4, wherein the magnetic field distribution curve of the magnetic field generated by the two winding magnetic pole pairs along the X direction is a power exponent function, the power exponent of the power exponent function is between 1.8 and 2.2, and the power exponent is not a constant over the whole curve.
6. The electron curtain accelerator according to claim 1, comprising a vacuum tube through which the electron gun and the beam spot processing apparatus communicate, and a vacuum box including a vacuum chamber, an inlet and an outlet, both of which communicate with the vacuum chamber, the inlet communicating with an exit of the beam spot processing apparatus, the outlet communicating with the focusing apparatus, the size of the vacuum chamber in the X-direction gradually increasing from the inlet toward the outlet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211191741.3A CN115529710B (en) | 2022-09-28 | 2022-09-28 | Electronic curtain accelerator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211191741.3A CN115529710B (en) | 2022-09-28 | 2022-09-28 | Electronic curtain accelerator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115529710A CN115529710A (en) | 2022-12-27 |
| CN115529710B true CN115529710B (en) | 2024-02-20 |
Family
ID=84698874
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211191741.3A Active CN115529710B (en) | 2022-09-28 | 2022-09-28 | Electronic curtain accelerator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115529710B (en) |
Citations (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5920957A (en) * | 1982-07-26 | 1984-02-02 | Nisshin Haiboruteeji Kk | Electron beam irradiator |
| US4543487A (en) * | 1983-05-03 | 1985-09-24 | Enso-Gutzeit Oy | Procedure and means for creating an electron curtain with adjustable intensity distribution |
| US4572957A (en) * | 1983-05-03 | 1986-02-25 | Enso-Gutzeit Oy | Means for creating an electron curtain |
| US4893058A (en) * | 1987-05-26 | 1990-01-09 | Commissariat A L'energie Atomique | Array electron accelerator |
| CN1040705A (en) * | 1988-08-30 | 1990-03-21 | 汤姆森消费电子有限公司 | Electron gun structure with heater tab with locating means of reinforcing |
| JPH03280341A (en) * | 1990-03-28 | 1991-12-11 | Iwasaki Electric Co Ltd | Electron beam irradiation device |
| CN201590387U (en) * | 2009-12-17 | 2010-09-22 | 北京有色金属研究总院 | Gun core of electronic gun |
| JP2011141176A (en) * | 2010-01-07 | 2011-07-21 | Life Technology Research Institute Inc | Electron beam irradiator |
| CN102800546A (en) * | 2012-08-23 | 2012-11-28 | 汇佳生物仪器（上海）有限公司 | Cluster tip wavefront field emission cold cathode X-ray tube with counterpoint hole control strip |
| CN103140012A (en) * | 2011-11-25 | 2013-06-05 | 中国原子能科学研究院 | Electron Irradiation Accelerator with Titanium Film Protection Function |
| CN104681230A (en) * | 2014-12-16 | 2015-06-03 | 中国原子能科学研究院 | Beam homogenizing sextupole magnet for accelerator |
| CN104717822A (en) * | 2015-03-30 | 2015-06-17 | 同方威视技术股份有限公司 | Electron curtain accelerator and control method |
| CN110337172A (en) * | 2019-06-26 | 2019-10-15 | 北京智束科技有限公司 | A kind of electrocurtain accelerator |
| CN210274659U (en) * | 2019-06-26 | 2020-04-07 | 北京智束科技有限公司 | Electron curtain accelerator and filament assembly thereof |
| CN111033689A (en) * | 2017-06-27 | 2020-04-17 | 彼得·F·范德莫伊伦 | Method and system for plasma deposition and processing |
| CN111885809A (en) * | 2020-06-30 | 2020-11-03 | 中国原子能科学研究院 | Wide-energy large-beam-spot electron accelerator |
| CN112086331A (en) * | 2019-06-12 | 2020-12-15 | 新日本无线株式会社 | Electron gun |
| CN113692101A (en) * | 2020-05-19 | 2021-11-23 | 四川智研科技有限公司 | Compact electron accelerator |
| CN215575693U (en) * | 2021-09-16 | 2022-01-18 | 中国科学院高能物理研究所 | Electron gun testing device and electron gun testing system |
| CN114980469A (en) * | 2022-04-25 | 2022-08-30 | 中国科学技术大学 | Modularized spliced oxide cathode plasma source |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE202007019712U1 (en) * | 2006-07-17 | 2016-05-18 | Nuctech Company Limited | irradiator |
-
2022
- 2022-09-28 CN CN202211191741.3A patent/CN115529710B/en active Active
Patent Citations (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5920957A (en) * | 1982-07-26 | 1984-02-02 | Nisshin Haiboruteeji Kk | Electron beam irradiator |
| US4543487A (en) * | 1983-05-03 | 1985-09-24 | Enso-Gutzeit Oy | Procedure and means for creating an electron curtain with adjustable intensity distribution |
| US4572957A (en) * | 1983-05-03 | 1986-02-25 | Enso-Gutzeit Oy | Means for creating an electron curtain |
| US4893058A (en) * | 1987-05-26 | 1990-01-09 | Commissariat A L'energie Atomique | Array electron accelerator |
| CN1040705A (en) * | 1988-08-30 | 1990-03-21 | 汤姆森消费电子有限公司 | Electron gun structure with heater tab with locating means of reinforcing |
| JPH03280341A (en) * | 1990-03-28 | 1991-12-11 | Iwasaki Electric Co Ltd | Electron beam irradiation device |
| CN201590387U (en) * | 2009-12-17 | 2010-09-22 | 北京有色金属研究总院 | Gun core of electronic gun |
| JP2011141176A (en) * | 2010-01-07 | 2011-07-21 | Life Technology Research Institute Inc | Electron beam irradiator |
| CN103140012A (en) * | 2011-11-25 | 2013-06-05 | 中国原子能科学研究院 | Electron Irradiation Accelerator with Titanium Film Protection Function |
| CN102800546A (en) * | 2012-08-23 | 2012-11-28 | 汇佳生物仪器（上海）有限公司 | Cluster tip wavefront field emission cold cathode X-ray tube with counterpoint hole control strip |
| CN104681230A (en) * | 2014-12-16 | 2015-06-03 | 中国原子能科学研究院 | Beam homogenizing sextupole magnet for accelerator |
| CN104717822A (en) * | 2015-03-30 | 2015-06-17 | 同方威视技术股份有限公司 | Electron curtain accelerator and control method |
| CN111033689A (en) * | 2017-06-27 | 2020-04-17 | 彼得·F·范德莫伊伦 | Method and system for plasma deposition and processing |
| CN112086331A (en) * | 2019-06-12 | 2020-12-15 | 新日本无线株式会社 | Electron gun |
| CN110337172A (en) * | 2019-06-26 | 2019-10-15 | 北京智束科技有限公司 | A kind of electrocurtain accelerator |
| CN210274659U (en) * | 2019-06-26 | 2020-04-07 | 北京智束科技有限公司 | Electron curtain accelerator and filament assembly thereof |
| CN113692101A (en) * | 2020-05-19 | 2021-11-23 | 四川智研科技有限公司 | Compact electron accelerator |
| CN111885809A (en) * | 2020-06-30 | 2020-11-03 | 中国原子能科学研究院 | Wide-energy large-beam-spot electron accelerator |
| CN215575693U (en) * | 2021-09-16 | 2022-01-18 | 中国科学院高能物理研究所 | Electron gun testing device and electron gun testing system |
| CN114980469A (en) * | 2022-04-25 | 2022-08-30 | 中国科学技术大学 | Modularized spliced oxide cathode plasma source |
Non-Patent Citations (6)
| Title |
|---|
| CIAE 直线加速器技术的创新发展;王国宝等;原子能科学技术;第54卷;293-302 * |
| The comparison of the elements for the homogenizing charged particle irradiation;Li, JH 等;Laser and Particle Beams;第29卷(第1期);87-94 * |
| 医用电子直线加速器的射束偏转系统;杨绍洲等;中国医学物理杂志;第17卷(第3期);129-131, 133 * |
| 王常强 ; 向益淮 ; 李金海 ; 杨京鹤 ; .束流均匀化聚焦六级磁铁设计.中国原子能科学研究院年报.2020,173-174. * |
| 电子辐照加速器束流扫描均匀化研究;李金海等;原子能科学技术;第49卷;564-568 * |
| 纵向多灯丝电子帘加速器的束流不均匀度;任杰;朱希恺;张宇田;李德明;朱南康;;原子能科学技术;44(第08期);121-125 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115529710A (en) | 2022-12-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100926398B1 (en) | Controlling the characteristics of ribbon-shaped implanter ion-beams | |
| TWI539482B (en) | Particle-optical systems and arrangements and particle-optical components for such systems and arrangements | |
| KR101861210B1 (en) | Electron lens and the electron beam device | |
| US8390201B2 (en) | Multi-column electron beam exposure apparatus and magnetic field generation device | |
| JPH0230038A (en) | Electron cyclotron resonance ion source | |
| JPH10233299A (en) | Charged particle beam expander | |
| CN108566721B (en) | Linear accelerator and synchrotron | |
| KR20120005026A (en) | Conjugated icp and ecr plasma sources for wide ribbon ion beam generation and control | |
| US20020186814A1 (en) | Star pinch X-ray and extreme ultraviolet photon source | |
| JP2019149387A (en) | Compact deflecting magnet | |
| JP2000285840A (en) | Electron gun, drawing device using electron gun and electron beam application device | |
| CN115529710B (en) | Electronic curtain accelerator | |
| US9799489B2 (en) | Exposure apparatus | |
| US20150108894A1 (en) | Wide metal-free plasma flood gun | |
| KR101398729B1 (en) | Ion implantation apparatus | |
| WO2020166116A1 (en) | Ion source, circular accelerator using same, and particle beam therapy system | |
| TWI718274B (en) | Multicolumn device and multicolumn charged particle beam exposure apparatus | |
| Skaritka et al. | Conceptual design of a polarized electron ion collider at Brookhaven National Laboratory | |
| JP2005174568A (en) | Object lens, electron beam device, and manufacturing method of device using them | |
| JP2016219292A (en) | Electronic lens and multicolumn electron beam device | |
| KR102391045B1 (en) | Plasma Apparatus With An electron Beam Emission Source | |
| JP2004134171A (en) | Electron gun, electron beam lithography system, and electron beam lithography method | |
| TW201442056A (en) | Ion source and ion implantation system | |
| JP2005078912A (en) | Ion mass separation apparatus, ion implanter, and ion mass separation method | |
| RU2267830C1 (en) | Sealed off electron gun for taking band electron flow from vacuum area of gun to atmosphere or other gaseous environment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |