CN209641620U - A kind of X-ray tube of controllable focus - Google Patents
A kind of X-ray tube of controllable focus Download PDFInfo
- Publication number
- CN209641620U CN209641620U CN201920586566.5U CN201920586566U CN209641620U CN 209641620 U CN209641620 U CN 209641620U CN 201920586566 U CN201920586566 U CN 201920586566U CN 209641620 U CN209641620 U CN 209641620U
- Authority
- CN
- China
- Prior art keywords
- grid
- emission source
- ray tube
- focus
- controllable focus
- 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
Abstract
The utility model discloses a kind of X-ray tube of controllable focus, belongs to the field of medical instrument technology.The X-ray tube of the controllable focus includes insulating ceramics between cathode assembly, anode assemblies and anode；Wherein, the cathode assembly includes emission source and stem, and emission source described in the stem electrified regulation makes it generate electron cloud, the cathode assembly further include: grid, between the emission source and the anode assemblies；Gate terminal adjusts the current potential of the grid by the gate terminal, makes it below the current potential of the emission source.The utility model is by adjusting grid potential, the unwrapping wire switching of Microsecond grade may be implemented, by the composite structure of gate structure or grid and magnetic quadrupole lens, the switching of multifocal dimension and shape is realized, and focus all has a greater change range in length and width direction.
Description
Technical field
The utility model relates to the field of medical instrument technology, in particular to a kind of X-ray tube of controllable focus.
Background technique
X-ray tube is focused on to generate X-ray in the performance of the every field such as medical diagnosis, safety inspection and nondestructive inspection
The effect wanted.The basic principle of X-ray tube is that cathode filament heats the thermoelectron ejected, in the acceleration of yin-yang interpolar
Target disc is struck under electric field action；Wherein about 1% energy is converted into X-ray, and the energy of residue about 99% is converted into thermal energy simultaneously
It is dissipated on anode disc.Area in electronic impact to anode disc forms actual focal spot, and actual focal spot is perpendicular to X-ray
Projection on tube axis direction forms effective focal spot.Effective focal spot reduces the clarity for being conducive to improve image, but correspondingly,
The maximum power that target disc can bear also reduces.Therefore, many X-ray tube designs have size focus, and large focal spot bears larger function
Rate generates the X-ray of enough brightness；And small focus bears smaller power, but can produce image more high-definition.
Traditional bifocus X-ray tube uses size filament, by different filament lengths, diameter and grid spacing come real
Existing two focuses of size.It needs reasonable position to put simultaneously to design with electrode shape, so that two focuses of size all focus on
Same position.As shown in Figure 1, its is compact-sized, processing and technique are multiple for a kind of cathode of typical traditional bifocus X-ray tube
It is miscellaneous, and can only realize two kinds of fixed focal spot sizes.If necessary to multifocal, then needs to increase filament, lead to design difficulty
Increase；In addition, Conventional X-ray tubes are used to high pressure or whether opening and shutting off control unwrapping wire of heater current.This side
Formula switch speed is slow, and in the application such as modern industry CT or static state CT, it would be desirable to be able to it is quickly carried out with Millisecond or even Microsecond grade
The X-ray tube of unwrapping wire switching, Conventional X-ray tubes are not able to satisfy such demand.
Utility model content
The purpose of this utility model is to provide a kind of X-ray tube of controllable focus, with solve to occur in background technique
Problem.
In order to solve the above technical problems, the utility model provides a kind of X-ray tube of controllable focus, including cathode assembly,
Insulating ceramics between anode assemblies and anode；Wherein, the cathode assembly includes emission source and stem, the stem electrified regulation institute
Emission source is stated, it is made to generate electron cloud, the cathode assembly further include:
Grid, between the emission source and the anode assemblies；
Gate terminal adjusts the current potential of the grid by the gate terminal, makes it below the emission source
Current potential.
Optionally, the X-ray tube of the controllable focus further includes secondary foci control system, secondary foci control system
System includes magnetic quadrupole lens and several coils being wrapped on the magnetic quadrupole lens.
Optionally, the magnetic quadrupole lens includes several magnetic cores, several described coils are respectively wound around the magnetic core
On.
Optionally, the secondary foci control system further includes several deflection coils, is wrapped in the magnetic quadrupole lens
On.
Optionally, several described deflection coils be respectively wound around the magnetic quadrupole lens periphery or the magnetic core
On.
Optionally, the grid includes the first grid and second grid being divided into two in the emission source width direction,
With two focusing pieces being divided into two in the emission source length direction；The first grid and the second grid are respectively placed in
Two current potentials of opposite height.
Optionally, the grid includes the first grid and second grid being divided into two in the emission source width direction,
With the third grid and the 4th grid being divided into two in the emission source length direction；The third grid and the 4th grid
It is respectively placed in two current potentials of opposite height.
Optionally, the emission source is spiral D-shaped tungsten wire.
Optionally, the emission source is tungsten plate filament, dispenser-type cathode or LaB6 cathode.
The utility model has the following beneficial effects:
(1) by adjusting grid potential, the unwrapping wire switching of Microsecond grade may be implemented (i.e. unwrapping wire is opened and shut off)；
(2) by the composite structure of gate structure or grid and magnetic quadrupole lens, multifocal dimension and shape is realized
Switching, and focus all has a greater change range in length and width direction；
(3) by using D-shaped filament, Microfocus X-ray may be implemented, and better focus quality can be obtained.
Detailed description of the invention
Fig. 1 is the cathode construction schematic diagram of traditional bifocus X-ray tube；
Fig. 2 is the structural schematic diagram of the X-ray tube of controllable focus provided by the utility model；
Fig. 3 is the structural schematic diagram of spiral D-shaped tungsten wire；
Fig. 4 is the schematic diagram that conventional helical circle tungsten wire launches electronics；
Fig. 5 is the schematic diagram that spiral D-shaped tungsten wire launches electronics；
Fig. 6 is the structural schematic diagram of secondary foci control system；
Fig. 7 is the structural schematic diagram of the secondary foci control system of band-offset switch coil；
Fig. 8 is another structural schematic diagram of the secondary foci control system of band-offset switch coil；
Fig. 9 is a kind of realization structural schematic diagram of grid；
Figure 10 is that the another of grid realizes structural schematic diagram.
Specific embodiment
Below in conjunction with the drawings and specific embodiments to the utility model proposes the X-ray tube of controllable focus a kind of make into one
Step is described in detail.According to following explanation and claims, will be become apparent from feature the advantages of the utility model.It should be noted
It is that attached drawing is all made of very simplified form and using non-accurate ratio, only to facilitate, lucidly aid in illustrating this reality
With the purpose of new embodiment.
Embodiment one
The utility model provides a kind of X-ray tube of controllable focus, and structure is as shown in Figure 2.The X of the controllable focus
Ray tube includes insulating ceramics between cathode assembly, anode assemblies and anode；Wherein, the cathode assembly includes emission source 1 and core
Column 2, emission source 1 described in 2 electrified regulation of stem make it generate the electron cloud by electronically forming, which is gathered in institute
State the surface of emission source 1；The anode assemblies include anode disc 3 and anode pedestal 4.When electron cloud is by cathode and anode component
Between accelerating field effect when, produce X-ray on electron bombardment to the anode disc 3.
Specifically, helical tungsten filament can be used in the emission source 1；It preferably, is spiral D-shaped tungsten wire, as shown in Figure 3.It passes
Emission source of uniting is usually spiral circle tungsten wire, and the initial velocity for launching electronics is approximately perpendicular to filament surface, as shown in figure 4,
Therefore electronics diverging is very serious, this is also to cause to limit the reason that focal spot size cannot be too small.The utility model uses spiral shell
D-shaped tungsten wire is revolved, and electron emission face is suitably limited in region as shown in Figure 5, the electronics initial velocity emitted in this way is consistent,
Emittance is more preferable, is easy to focus design, to be also easy to realize Microfocus X-ray.Alternatively, it is also possible to use tungsten plate filament, reserve type
Cathode or LaB6 cathode.
Specifically, the cathode assembly further includes grid 5 and gate terminal 6, the grid 5 is located at the transmitting
Between source 1 and the anode assemblies, the current potential of the grid 5 is adjusted by the gate terminal 6, makes it below the transmitting
The current potential in source 1, the variation of the equipotential lines thus caused cause the surface area for capableing of launching electronics on the emission source 1 to reduce,
And the electric field force inwardly drawn is generated to electronics on 1 surface of emission source, so that electronics is preferably focused, thus Hong
The actual focal spot generated on the anode disc 3 is hit in emission source length direction and width direction (i.e. perpendicular to axis direction)
On all reduced.Therefore the current potential for adjusting the grid 5, can be realized the variation of focus size.But for the present embodiment one
In spiral D-shaped tungsten wire, adjust the spiral D-shaped tungsten wire caused by the current potential of the grid 2 in the amplitude of variation of width direction
Greater than the amplitude of variation of length direction.
Further, the X-ray tube of the controllable focus further includes secondary foci control system 7, passes through secondary foci control
System 7 processed spot size of focusing further is adjusted, so that the spiral D-shaped tungsten wire can achieve and width in length direction
Amplitude of variation similar in direction.
Specifically, passing through emulation when the current potential of the relatively described emission source 1 of current potential of the grid 5 changes to -700V from 0
Available actual focal spot width about becomes 0.2mm from 2.3mm, and actual focal spot length about becomes 1.6mm from 3.9mm.It is false
The inclination angle of the fixed anode disc 3 is 7 °, and the size (width × length) of corresponding optical focus is about that 2.3mm × 0.5mm is arrived
0.2mm×0.2mm.When the current potential of the grid 5 is equal with the current potential of the emission source 1, optical focus is in long strip.Pass through
The secondary foci control system 7 is taken, further adjustment can be carried out to length, the variation range of such Focus length is big
About reach the variation range of 1.8mm to 0.2mm.
The X-ray tube of the controllable focus, by being placed in the current potential of the grid 5 relative to the emission source 1 enough
Low current potential, can prevent the electron emission of the emission source 1, to realize the shutdown of grid 5.By taking the present embodiment one as an example,
X-ray can about be turned off in -3kV.Conventional X-ray tubes are by shutdown yin, yang component high pressure or reduce the emission source 1
Electric current makes the means such as its cooling to realize the shutdown of X-ray, and this mode switch speed is slow.And the utility model passes through the grid
5 current potential of pole is switched fast, and opening and shutting off for X-ray Microsecond grade may be implemented.It can effectively eliminate X-ray shutdown in this way to prolong
Radiation in late to the extra dosage of patient.The utility model is equally applicable in static CT or industry CT, in groups in use,
X-ray source can be switched fast by 5 current potential of grid.
Specifically, the secondary foci control system 7 is including magnetic quadrupole lens 71 and is wrapped in the magnetic quadrupole lens
Several coils 72 on 71.Referring to Fig. 6, the magnetic quadrupole lens 71 includes several magnetic cores 711, several described coils
72 are respectively wound around on the magnetic core 711.According to the current direction as shown in Fig. 6 block arrows, four magnetic poles be can produce such as Fig. 6 void
Magnetic field shown in line arrow.It will in one direction under the action of the magnetic field by the electron beam at 71 center of magnetic quadrupole lens
Upper convergence dissipates on another direction.In the utility model embodiment one, the magnetic quadrupole lens 71 is on the basis that grid focuses
Upper further progress focal point control.Its control mode can be can choose and be dissipated in Focus length direction by a variety of, will be burnt
Point length is elongated；Or selection is converged in Focus length direction, and Focus length is reduced；Also it can choose in length direction
It is largely converged, to generate over-focusing to achieve the effect that diverging.Similarly, focus point width can also be similar
Control.Secondary foci control is carried out by magnetic quadrupole lens 71, available wider focal variation range and flexible
Focus size.
Further, the secondary foci control system 7 further includes several deflection coils 73, is wrapped in the magnetic quadrupole
On lens 71.The deflection coil 73 can control focus and generate X-axis (i.e. emission source width direction) and Z axis (i.e. X-ray tube axis
Line direction) fly coke.The deflection coil 73 is respectively wound around the periphery of the magnetic quadrupole lens 71 as shown in Figure 7, Huo Zheru
On the magnetic core 711 shown in Fig. 8.As shown in Figure 7, Figure 8, it when deflection coil 73 is by the electric current in direction shown in solid, will produce
The magnetic field in direction shown in raw dotted line.Electron beam will deflect in vertical direction under the magnetic fields.If deflection coil 73
By the electric current with solid line opposite direction, then the magnetic field with dotted line opposite direction is generated.Similarly, in Fig. 7, change the left and right sides
Deflection coil 73 electric current, electron beam can be made to deflect in the horizontal direction；In Fig. 8, change the electric current of deflection coil 73, it can
To change polarity, deflect electron beam in the horizontal direction.It, can be with by taking Fig. 7 or deflection coil shown in Fig. 8 73
The X-axis and Z axis for realizing X-ray tube fly coke.
Embodiment two
The utility model embodiment two provides a kind of X-ray tube of controllable focus, distinguishes and is compared with embodiment one,
The grid 5 includes the first grid 51 and second grid 52 being divided into two in 1 width direction of emission source, and in the hair
Two focusing pieces 55 that 1 length direction of source is divided into two are penetrated, as shown in Figure 9；The first grid 51 and the second grid 52
Two current potentials of opposite height are respectively placed in, electron beam can also be deflected to a direction, i.e., X-axis flies coke.The auxiliary described in this way
Autofocus control system 7, which can according to need, only retains the winged burnt control function of Z axis.
Embodiment three
The utility model embodiment three provides a kind of X-ray tube of controllable focus, including cathode assembly, anode assemblies and
Insulating ceramics between anode；Wherein, the cathode assembly includes emission source 1 and stem 2, is emitted described in 2 electrified regulation of stem
Source 1, makes it generate the electron cloud by electronically forming, which is gathered in the surface of the emission source 1；The anode assemblies packet
Include anode disc 3 and anode pedestal 4.When electron cloud is acted on by the accelerating field between cathode and anode component, electron bombardment is arrived
X-ray is produced on the anode disc 3.
Specifically, helical tungsten filament can be used in the emission source 1；It preferably, is spiral D-shaped tungsten wire, as shown in Figure 3.It passes
Emission source of uniting is usually spiral circle tungsten wire, and the initial velocity for launching electronics is approximately perpendicular to filament surface, as shown in figure 4,
Therefore electronics diverging is very serious, this is also to cause to limit the reason that focal spot size cannot be too small.The utility model uses spiral shell
D-shaped tungsten wire is revolved, and electron emission face is suitably limited in region as shown in Figure 5, the electronics initial velocity emitted in this way is consistent,
Emittance is more preferable, is easy to focus design, to be also easy to realize Microfocus X-ray.Alternatively, it is also possible to use tungsten plate filament, reserve type
Cathode or LaB6 cathode.
Specifically, the cathode assembly further includes grid 5 and gate terminal 6, the grid 5 is located at the transmitting
Between source 1 and the anode assemblies, the current potential of the grid 5 is adjusted by the gate terminal 6, makes it below the transmitting
The current potential in source 1, the variation of the equipotential lines thus caused cause the surface area for capableing of launching electronics on the emission source 1 to reduce,
And the electric field force inwardly drawn is generated to electronics on 1 surface of emission source, so that electronics is preferably focused, thus Hong
The actual focal spot generated on the anode disc 3 is hit in emission source length direction and width direction (i.e. perpendicular to axis direction)
On all reduced.Therefore the current potential for adjusting the grid 5, can be realized the variation of focus size.But in embodiment one
Spiral D-shaped tungsten wire, it is big in the amplitude of variation of width direction to adjust the spiral D-shaped tungsten wire caused by the current potential of the grid 2
In the amplitude of variation of length direction.
Further, the grid 5 includes the first grid 51 and second being divided into two in the emission source width direction
Grid 52, in the third grid 53 and the 4th grid 54 that the emission source length direction is divided into two.By adjusting described first
The current potential of grid 51 and the second grid 52, the third grid 53 and the 4th grid 54, may be implemented different size
Focus, i.e. the length and width direction of optical focus can have large range of adjustment simultaneously.In addition, by the first grid
51 and the second grid 52 be placed in different potentials, it can be achieved that X-axis fly coke；By the third grid 53 and the 4th grid 54
Different potentials are placed in, it can be achieved that Z axis flies coke.Preferably, four grids are saturating according to shape as shown in Figure 10 one electric quadrupole of formation
Mirror, has better focus effect, and focus is also avoided to generate distortion.
Foregoing description is only the description to the utility model preferred embodiment, not to any limit of the scope of the utility model
Fixed, any change, the modification that the those of ordinary skill in the utility model field does according to the disclosure above content belong to right and want
Seek the protection scope of book.
Claims (9)
1. a kind of X-ray tube of controllable focus, including insulating ceramics between cathode assembly, anode assemblies and anode；Wherein, the yin
Pole component includes emission source and stem, and emission source described in the stem electrified regulation makes it generate electron cloud, which is characterized in that
The cathode assembly further include:
Grid, between the emission source and the anode assemblies；
Gate terminal adjusts the current potential of the grid by the gate terminal, makes it below the current potential of the emission source.
2. the X-ray tube of controllable focus as described in claim 1, which is characterized in that the X-ray tube of the controllable focus is also wrapped
Include secondary foci control system, the secondary foci control system includes magnetic quadrupole lens and is wrapped in the magnetic quadrupole lens
On several coils.
3. the X-ray tube of controllable focus as claimed in claim 2, which is characterized in that the magnetic quadrupole lens includes several
Magnetic core, several described coils are respectively wound around on the magnetic core.
4. the X-ray tube of controllable focus as claimed in claim 3, which is characterized in that the secondary foci control system is also wrapped
Several deflection coils are included, are wrapped on the magnetic quadrupole lens.
5. the X-ray tube of controllable focus as claimed in claim 4, which is characterized in that several described deflection coils twine respectively
It is wound on the periphery or the magnetic core of the magnetic quadrupole lens.
6. the X-ray tube of controllable focus as claimed in claim 5, which is characterized in that the grid is included in the emission source
The first grid and second grid that width direction is divided into two, and two focusing being divided into two in the emission source length direction
Piece；The first grid and the second grid are respectively placed in two current potentials of opposite height.
7. the X-ray tube of controllable focus as described in claim 1, which is characterized in that the grid is included in the emission source
The first grid and second grid that width direction is divided into two, and the third grid being divided into two in the emission source length direction
With the 4th grid；The third grid and the 4th grid are respectively placed in two current potentials of opposite height.
8. the X-ray tube of controllable focus as claimed in claims 6 or 7, which is characterized in that the emission source is spiral D-shaped tungsten
Silk.
9. the X-ray tube of controllable focus as claimed in claims 6 or 7, which is characterized in that the emission source is tungsten flat lamp
Silk, dispenser-type cathode or LaB6 cathode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920586566.5U CN209641620U (en) | 2019-04-26 | 2019-04-26 | A kind of X-ray tube of controllable focus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920586566.5U CN209641620U (en) | 2019-04-26 | 2019-04-26 | A kind of X-ray tube of controllable focus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209641620U true CN209641620U (en) | 2019-11-15 |
Family
ID=68497863
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920586566.5U Active CN209641620U (en) | 2019-04-26 | 2019-04-26 | A kind of X-ray tube of controllable focus |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209641620U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111048381A (en) * | 2019-11-29 | 2020-04-21 | 清华大学 | Beam scanning multi-focus pulse X-ray tube and CT (computed tomography) equipment |
-
2019
- 2019-04-26 CN CN201920586566.5U patent/CN209641620U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111048381A (en) * | 2019-11-29 | 2020-04-21 | 清华大学 | Beam scanning multi-focus pulse X-ray tube and CT (computed tomography) equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2775071B2 (en) | Charged particle beam generator | |
| JPS60254538A (en) | X-ray tube device | |
| US3970890A (en) | Plural beam cathode ray tube including an astigmatic electron lens and self-converging | |
| CN209641620U (en) | A kind of X-ray tube of controllable focus | |
| JP2862993B2 (en) | Electron gun for color cathode ray tube | |
| JP2002528878A (en) | X-ray tube providing variable imaging spot size | |
| JP2928282B2 (en) | Color picture tube equipment | |
| JP3369173B2 (en) | Electron gun with main lens with low voltage limiting aperture | |
| US5159240A (en) | Low voltage limiting aperture electron gun | |
| KR20020057585A (en) | Electron gun for color cathode ray tube | |
| JPH01200541A (en) | Cathode ray tube and its electron gun | |
| JPH06283112A (en) | Electron gun | |
| US3307061A (en) | Electrostatic return beam camera tube | |
| US7045943B2 (en) | Electron gun for cathode ray tube having third to fifth electrodes with different sized electron beam through holes | |
| US6841924B1 (en) | Low-voltage high-resolution einzel gun | |
| US6831400B2 (en) | Color cathode ray tube apparatus having auxiliary magnetic field generator | |
| WO2022021140A1 (en) | Visible light streak tube and electron-optical imaging system | |
| JP2645097B2 (en) | Color picture tube equipment | |
| JPS63198241A (en) | Color cathode tube | |
| JP2645071B2 (en) | Color picture tube equipment | |
| JP2588599B2 (en) | Cathode ray tube | |
| KR100439263B1 (en) | A Electron Gun Of The Color Cathode Ray Tube | |
| WO1995021456A1 (en) | Color cathode ray tube | |
| KR100546579B1 (en) | Electron gun for color cathode ray tube | |
| KR100459224B1 (en) | Electron gun for Cathode Ray Tube |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |