A shim coil, a design method of the shim coil, and a magnetic resonance imaging device

Abstract

The present application provides a shim coil, a design method of the shim coil, and a magnetic resonance imaging device, relating to the technical field of magnetic resonance. The shim coil includes: a capacitor component, an amplifier, a transmission component, and a resonance component; the capacitor component is connected to the amplifier; the first end of the transmission component is connected to a power supply circuit, and the second end of the transmission component is connected to both ends of the capacitor component to supply electrical energy and direct current to the shim coil; the resonance component is connected to both ends of the amplifier to block radio frequency signals. Since the magnetic resonance frequency during the operation of the magnetic resonance imaging device is relatively low, the present application realizes a large inductive impedance in the shim coil through the transmission component and the resonance component with relatively small volumes to block the radio frequency current. Through the action of the direct current, the normal function of the shim coil is not affected, and it is applicable to various types of flexible coils, reducing the complexity of the design and structure of the shim coil, thereby reducing the volume of the shim coil and saving the cost of the shim coil.

Description

Technical Field

[0001] The present application relates to the field of magnetic resonance technology. Specifically, it relates to a shim coil, a design method of the shim coil, and a magnetic resonance imaging device. Background Art

[0002] The image quality obtained in Magnetic Resonance Imaging (MRI) is affected by the uniformity of the main magnetic field B0. When the magnetic field is non-uniform, it will cause artifacts in the obtained image, such as: image blurring, signal loss, and severe distortion. The artifacts in the image will reduce the effectiveness of the image, thereby reducing the accuracy in diagnosis. Moreover, with the application of higher magnetic field strengths, the non-uniformity of the magnetic field almost increases linearly. Therefore, currently, the method of setting local shimming in the magnetic resonance device is generally adopted to improve the image quality.

[0003] In the prior art, the shim coil is usually designed by adding inductors in the coil to obtain a relatively stable magnetic field, so as to achieve the function of local shimming. However, a large inductor will occupy the space of the shim coil, making the design and structure of the shim coil complicated, and when the volume of the inductor is large, the type of the shim coil is greatly restricted, resulting in a high cost of the shim coil. Summary of the Invention

[0004] In view of this, the purpose of the embodiments of the present application is to provide a shim coil, a design method of the shim coil, and a magnetic resonance imaging device to improve the problem of high cost of the shim coil existing in the prior art.

[0005] To solve the above problems, in the first aspect, the embodiments of the present application provide a shim coil, which includes: a capacitor component, an amplifier, a transmission component, and a resonance component;

[0006] The capacitor component is connected to the amplifier;

[0007] The first end of the transmission component is connected to the power supply circuit, and the second end of the transmission component is connected to both ends of the capacitor component to provide electrical energy and direct current for the shim coil;

[0008] The resonance component is connected to both ends of the amplifier to block radio frequency signals.

[0009] In the above implementation process, by connecting a transmission component with a relatively high inductive impedance and a small volume and a resonant component to both ends of the capacitance component and the amplifier of the shim coil respectively to provide a direct current for the shim coil, the magnetic field of the shim coil is stabilized, and the function of local shimming is realized. Moreover, the transmission component and the resonant component can block the radio frequency current, so as not to affect the normal function of the shim coil. Using a transmission component and a resonant component with a small volume to replace an inductance component with a large inductance and a large volume can effectively reduce the space occupied by the device in the shim coil, so as to be applicable to various shim coils with a small volume such as AIR (Adaptive Image Reception) coils and flexible coils, improving the application range of the shim coil. Moreover, the transmission component can also replace the power line to supply power to the shim coil, further reducing the complexity of the design and structure of the shim coil, thereby reducing the volume of the shim coil and saving the cost of the shim coil.

[0010] Optionally, the transmission component includes: a transmission line and a first capacitor;

[0011] The first end of the transmission line is connected to the power supply circuit and the first capacitor;

[0012] The second end of the transmission line is connected to both ends of the capacitance component to provide electrical energy and direct current for the shim coil through the transmission line.

[0013] In the above implementation process, the transmission component includes a transmission line and a first capacitor. The first end of the transmission line is connected to the power supply circuit and the first capacitor, so as to conduct the direct current provided by the power supply circuit. The second end of the transmission line is connected to both ends of the capacitance component, so as to introduce the direct current into the capacitance component of the shim coil to stabilize the magnetic field of the shim coil, and can also provide working electrical energy for the shim coil through the transmission line. Using the transmission line to replace the power line in the shim coil effectively simplifies the design structure of the shim coil and reduces the device cost of the shim coil.

[0014] Optionally, the first end of the transmission line connected to the first capacitor is a short-circuit point;

[0015] The second end of the transmission line connected to the capacitance component is an open-circuit point to block the radio frequency signal through the short-circuit point and the open-circuit point.

[0016] In the above implementation process, the first capacitor can make the first end of the transmission line connected to it a short-circuit point for radio frequency current, and according to the impedance transformation characteristic of the transmission line, make the second end of the transmission line connected to the capacitance component an open-circuit point for radio frequency current, so that the transmission component can block the radio frequency signal of the radio frequency current based on the short-circuit point and the open-circuit point to ensure the normal radio frequency reception function and characteristics of the shim coil.

[0017] Optionally, the length of the transmission line is set to: An impedance transformation between the short - circuit point and the open - circuit point can be achieved through the transmission line, where n is a natural number greater than or equal to 0, and λ is the wavelength.

[0018] In the above implementation process, in order to enable the transmission line to have impedance transformation characteristics, the length of the transmission line can be set according to the design requirements, so that transmission lines of different lengths can all have the impedance transformation characteristics of a quarter - wavelength. Thus, it is ensured that the first end of the transmission line connected to the first capacitor is the short - circuit point, and the second end connected to the capacitor assembly is the open - circuit point, realizing the impedance transformation between the short - circuit point and the open - circuit point to block the RF signal of the RF current and conduct the DC signal of the DC current. It can enable the transmission component to provide electrical energy and DC current for the shim coil while not affecting the normal RF reception function and characteristics of the shim coil. Effectively improves the design freedom of the transmission line and is applicable to shim coils of various structures.

[0019] Optionally, the transmission line is a coaxial cable, and the coaxial cable includes: an inner conductor and an outer conductor;

[0020] The inner conductor and the outer conductor are connected through the first capacitor.

[0021] In the above implementation process, in order to ensure that the shim coil has a complete current loop and circuit, a coaxial cable can be used as the transmission line for connection. The coaxial cable is composed of two coaxial cylindrical conductors, that is, composed of a coaxial inner conductor and outer conductor. The inner conductor and the outer conductor are connected through a first capacitor with a relatively large capacitance value to enable the coaxial cable to block the RF signal.

[0022] Optionally, the first end of the inner conductor is connected to the first end of the outer conductor through the first capacitor;

[0023] The first end of the inner conductor is connected to the power supply circuit;

[0024] The second end of the inner conductor is connected to the first end of the capacitor assembly; the second end of the outer conductor is connected to the second end of the capacitor assembly.

[0025] In the above implementation process, the first end of the inner conductor is connected to the first end of the outer conductor through the first capacitor, so that the port of the coaxial cable close to the first capacitor is the RF short - circuit point. The second end of the inner conductor and the second end of the outer conductor are respectively connected to the two ports of the capacitor assembly. Thus, according to the length setting of the coaxial cable, the port of the coaxial cable close to the capacitor assembly is the RF open - circuit point. It can block the RF signal and conduct the DC signal according to the connection and setting of the coaxial cable, enabling the coaxial cable to provide electrical energy and DC current for the shim coil without affecting the normal RF reception function and characteristics of the shim coil.

[0026] Optionally, the resonant component includes: a second capacitor and a first inductor;

[0027] The second capacitor is connected in parallel with the first inductor;

[0028] The first ends of the second capacitor and the first inductor are connected to the first end of the amplifier;

[0029] The second ends of the second capacitor and the first inductor are connected to the second end of the amplifier.

[0030] In the above implementation process, the resonance component includes a second capacitor and a first inductor connected in parallel. The first ends of the parallel-connected second capacitor and first inductor are connected to the first end of the amplifier, and the second ends of the second capacitor and the first inductor are connected to the second end of the amplifier, so that the resonance component can be arranged at both ends of the amplifier to block the radio frequency signal of the radio frequency current in the shim coil through the parallel resonance circuit, and can conduct the direct current, so that the resonance component does not affect the normal radio frequency reception function and performance of the amplifier and the shim coil.

[0031] Optionally, the second capacitor and the first inductor are resonance devices with sizes smaller than a preset threshold to block the radio frequency signal.

[0032] In the above implementation process, the second capacitor and the first inductor are capacitor devices and inductor devices with smaller sizes, which will not have a great impact on the structure of the shim coil and can be used in various flexible coils. Moreover, the second capacitor and the first inductor are also capacitor devices and inductor devices that can resonate at the applied frequency points, so as to form a high impedance to the radio frequency current according to the parallel circuit of the resonant second capacitor and first inductor to block the radio frequency signal.

[0033] In a second aspect, an embodiment of the present application also provides a design method for a shim coil, and the method includes:

[0034] Connect the first end of the transmission component to the power supply circuit;

[0035] Connect the second end of the transmission component to both ends of the capacitor component of the shim coil to supply electrical energy and direct current to the shim coil through the transmission component;

[0036] Connect a resonance component at both ends of the amplifier connected to the capacitor component to block the radio frequency signal through the resonance component.

[0037] In a third aspect, an embodiment of the present application also provides a magnetic resonance imaging device, and the magnetic resonance imaging device includes the shim coil described in any one of the above.

[0038] In summary, the present application provides a shimming coil, a design method of the shimming coil, and a magnetic resonance imaging device. By connecting a transmission component and a resonance component with a relatively small volume in the shimming coil, a relatively large inductive impedance is achieved to block the radio frequency current, and under the action of a direct current, the magnetic field is stabilized without affecting the normal function of the shimming coil. It is applicable to various types of shimming coils for stabilizing the magnetic field, such as flexible coils, reducing the complexity of the design and structure of the shimming coil, thereby reducing the volume of the shimming coil and saving the cost of the shimming coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the accompanying drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0040] Figure 1 FIG. is a schematic structural diagram of a shimming coil provided by an embodiment of the present application;

[0041] Figure 2 FIG. is a specific structural diagram of a shimming coil provided by an embodiment of the present application;

[0042] Figure 3 FIG. is a schematic flowchart of a design method of a shimming coil provided by an embodiment of the present application.

[0043] Reference numerals: 100 - shimming coil; 110 - capacitor component; 120 - amplifier; 130 - transmission component; 140 - resonance component; 150 - power supply circuit; 131 - transmission line; 132 - first capacitor; 133 - inner shaft; 134 - outer shaft; 141 - second capacitor; 142 - first inductor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts belong to the scope protected by the embodiments of the present application.

[0045] During magnetic resonance imaging, if the magnetic field is non-uniform / variable in magnitude within a certain range, the Larmor precession frequencies of the hydrogen protons contained in an identical piece of matter within this range will be different. When this matter receives a radiofrequency field of a certain frequency, the hydrogen protons in some regions will not be able to resonate / deflect. Without deflection, no MR signal can be generated, thus affecting the quality of the image obtained by imaging, resulting in situations such as blurred images, signal loss, and severe distortion.

[0046] Currently, in order to improve the stability of the magnetic field during magnetic resonance imaging, thereby improving the quality of the images during magnetic resonance imaging, and to improve the accuracy of doctors' diagnoses based on the images, a method of setting shim coils in magnetic resonance imaging equipment is adopted. Since the frequency during magnetic resonance is relatively low, therefore, in order to implement a larger radiofrequency choke to block the radiofrequency circuit and conduct low-frequency or direct current, currently when designing the shim coil, in order not to affect the normal radiofrequency reception function of the coil, an inductor with a relatively large inductance is usually added to the shim coil, so that the shim coil has a direct current, has a relatively stable magnetic field, and moreover, due to the relatively large inductance, the radiofrequency current cannot pass through the inductor, and the shim coil can also normally sense the spatial signal and operate as a receiving coil, etc.

[0047] However, for an inductor with a relatively large inductance, the corresponding inductor component has a relatively large volume. In actual applications, it will occupy a relatively large space in the shim coil, making the design and structure of the shim coil complicated, and will also increase the volume of the shim coil. Moreover, an inductor with a relatively large volume cannot be installed in a flexible coil such as an AIR coil for use, which greatly limits the type of shim coil, resulting in a relatively high cost of the shim coil in current magnetic resonance imaging equipment and a relatively small range of use, unable to meet the requirements of magnetic resonance imaging.

[0048] To solve the above problems, the embodiments of the present application provide a shim coil. Please refer to Figure 1 , Figure 1 is a schematic structural diagram of a shim coil provided by an embodiment of the present application. The shim coil 100 may include: a capacitor component 110, an amplifier 120, a transmission component 130, and a resonance component 140.

[0049] Among them, the capacitor component 110 is connected to the amplifier 120; the first end of the transmission component 130 is connected to the power supply circuit 150, and the second end of the transmission component 130 is connected to both ends of the capacitor component 110 to supply electrical energy and direct current to the shim coil 100; the resonance component 140 is connected to both ends of the amplifier 120 to block radiofrequency signals.

[0050] Optionally, the capacitor assembly 110 may be composed of a second inductor, a diode, and a third capacitor to enable the coil receiving unit to achieve the functions of tuning and decoupling through the respective components. The amplifier 120 may be a preamplifier or a low-noise amplifier connected to the capacitor assembly 110 through the coil. The power supply circuit 150 is a DC power supply circuit to provide a DC current for the transmission component 130 to charge the shim coil 100 and perform local shimming.

[0051] Optionally, the second end of the transmission component 130 is connected to both ends of the capacitor assembly 110, and can pass the DC current of the power supply circuit 150 connected to the first end of the transmission component 130 into the shim coil 100 to stabilize the magnetic field of the shim coil 100 and achieve the function of local shimming.

[0052] It should be noted that in order to implement a larger RF choke to block the RF circuit and conduct low-frequency or DC current, the transmission component 130 and the resonant component 140 are high-impedance components with a relatively high inductance for RF signals. They can block the RF signals of the RF current while passing the DC current, so that the original capacitor assembly 110 in the shim coil 100 and the amplifier 120 can normally conduct RF signals and perform corresponding processing, enabling the shim coil 100 to work normally without affecting the normal receiving function and other characteristics of the shim coil 100.

[0053] Optionally, since there is no limit on the inductance values of the transmission component 130 and the resonant component 140, both the transmission component 130 and the resonant component 140 can be components with a relatively small volume. When the transmission component 130 and the resonant component 140 are connected to the shim coil 100, they will not have a great impact on the structure of the shim coil 100 and can be applied to flexible coils such as AIR coils, enabling the flexible coil to also have the function of local shimming.

[0054] Optionally, please refer to Figure 2 , Figure 2 which is a schematic structural diagram of a shim coil provided by an embodiment of the present application. Among them, the transmission component 130 may further include a transmission line 131 and a first capacitor 132.

[0055] Optionally, the first end of the transmission line 131 is connected to the power supply circuit 150 and the first capacitor 132; the second end of the transmission line 131 is connected to both ends of the capacitor assembly 110 to supply electrical energy and direct current to the shimming coil 100 through the transmission line 131. By connecting both ends of the transmission line 131 to the power supply circuit 150 and the capacitor assembly 110, the direct current provided in the power supply circuit 150 is transmitted into the shimming coil 100 to supply electrical energy and direct current to the shimming coil 100, and the function of local shimming is realized by the applied direct current. It is also possible to replace the power supply line of the shimming coil 100 with the transmission line 131, and the power supply circuit 150 supplies the electrical energy and direct current required during the operation of the shimming coil 100, thereby saving the design and material costs of the power supply line and further reducing the structural complexity and cost of the shimming coil 100.

[0056] Optionally, the first end of the transmission line 131 connected to the first capacitor 132 is a short-circuit point; the second end of the transmission line 131 connected to the capacitor assembly 110 is an open-circuit point to block the radio frequency signal through the short-circuit point and the open-circuit point. By connecting the first capacitor 132 to the first end of the transmission line 131, the first end of the transmission line 131 is made into a short-circuit point for radio frequency current through the first capacitor 132 with a relatively large capacitance value, and according to the impedance transformation characteristic of the transmission line 131, the second end of the transmission line 131 connected to the capacitor assembly 110 is made into an open-circuit point for radio frequency current, so that the transmission assembly 130 can block the radio frequency signal of the radio frequency current based on the short-circuit point and the open-circuit point to ensure the normal radio frequency reception function and characteristics of the shimming coil 100.

[0057] Optionally, in order to enable the transmission line 131 to have impedance transformation characteristics (Impedancetranslation), the length of the transmission line 131 can be set according to the design requirements and actual situation. The length of the transmission line 131 can be to achieve impedance transformation between the short-circuit point and the open-circuit point through the transmission line 131, where n is a natural number greater than or equal to 0, and λ is the wavelength.

[0058] It should be noted that since the transmission line 131 with a half wavelength has impedance holding characteristics, while the transmission line 131 with a quarter wavelength has impedance transformation characteristics, therefore, the half wavelength can be used as the multiple length of the transmission line 131 selected according to the design requirements and actual situation, and the quarter wavelength can be used as the length of the transmission line 131 to achieve impedance transformation characteristics, so that transmission lines 131 with different lengths can all have the impedance transformation characteristics of a quarter wavelength, thereby ensuring that the first end of the transmission line 131 connected to the first capacitor 132 is a short-circuit point, the second end connected to the capacitor assembly 110 is an open-circuit point, realizing impedance transformation between the short-circuit point and the open-circuit point to block the radio frequency signal of the radio frequency current and conduct the direct current signal of the direct current.

[0059] For example, the capacitance value of the first capacitor 132 can be set to 10 nF, or can be set to other capacitance values according to design requirements and actual conditions.

[0060] Optionally, the transmission line 131 can be a coaxial line or a power line to ensure that the shimming coil 100 has a complete current loop and circuit. A coaxial line is a guiding system composed of two coaxial cylindrical conductors, and is a broadband microwave transmission line 131 with air or high-frequency dielectric filled between the inner and outer conductors. When the transmission line 131 is a coaxial line, the coaxial line can include a coaxial inner shaft 133 and an outer shaft 134. The inner shaft 133 and the outer shaft 134 are connected by the first capacitor 132. The connection method can be that the first end of the inner shaft 133 and the first end of the outer shaft 134 are connected by the first capacitor 132, so that the port of the coaxial line close to the first capacitor 132 is a radio frequency short circuit point. The first end of the inner shaft 133 is also connected to the power supply circuit 150 to transmit direct current through the coaxial line.

[0061] Optionally, the second end of the coaxial line can be opened, so that the second ends of the inner shaft 133 and the outer shaft 134 are respectively connected to the first end and the second end of the capacitor assembly 110 to ensure that the entire shimming coil 100 has a complete current loop and circuit, and can also make the port of the coaxial line close to the capacitor assembly 110 be a radio frequency open circuit point according to the length setting of the coaxial line. According to the connection and setting of the coaxial line, radio frequency signals can be blocked and direct current signals can be conducted, so that the coaxial line can provide electrical energy and direct current for the shimming coil 100 without affecting the normal radio frequency reception function and characteristics of the shimming coil 100.

[0062] Optionally, the resonant component 140 can include: a second capacitor 141 and a first inductor 142. Among them, the second capacitor 141 is connected in parallel with the first inductor 142; the first ends of the second capacitor 141 and the first inductor 142 are connected to the first end of the amplifier 120; the second ends of the second capacitor 141 and the first inductor 142 are connected to the second end of the amplifier 120. It can make the resonant component 140 be able to be arranged at both ends of the amplifier 120. The resonant parallel circuit is a high-impedance circuit for radio frequency current, so as to block the radio frequency signal of the radio frequency current in the shimming coil 100 through the resonant component 140, so that the resonant component 140 does not affect the normal radio frequency reception function and performance of the amplifier 120 and the shimming coil 100. And it can conduct direct current so that the direct current can flow back to the ground terminal of the current through the first inductor 142.

[0063] It should be noted that the capacitance value of the second capacitor 141 and the inductance value of the first inductor 142 are not limited. The second capacitor 141 and the first inductor 142 only need to be capacitor components and inductor components that can resonate at the applied frequency point, that is Therefore, the second capacitor 141 and the first inductor 142 can adopt components with smaller capacitance and inductance values. Correspondingly, when the capacitance and inductance values are small, the volume sizes of the second capacitor 141 and the first inductor 142 are also small, so that the sizes of the second capacitor 141 and the first inductor 142 can meet the preset threshold during design, will not have a great impact on the structure of the shimming coil 100, nor will it have a great impact on the overall circuit structure of the shimming coil 100, and can be used in a variety of flexible coils.

[0064] Optionally, please refer to Figure 3 , Figure 3 which is a schematic flowchart of a design method for a shimming coil provided by an embodiment of the present application. The method may include steps S200-S400.

[0065] Step S200: Connect the first end of the transmission component to the power supply circuit.

[0066] Among them, the power supply circuit is a circuit that provides direct current, so as to transmit the direct current to the shimming coil through the transmission component.

[0067] Step S300: Connect the second end of the transmission component to both ends of the capacitor component of the shimming coil, so as to supply electrical energy and direct current to the shimming coil through the transmission component.

[0068] Among them, the second end of the transmission component can be opened to be connected to both ends of the capacitor component, so as to supply electrical energy and direct current to the shimming coil, so as to stabilize the magnetic field of the shimming coil and realize the function of local shimming.

[0069] Step S400: Connect a resonance component to both ends of the amplifier connected to the capacitor component, so as to block the radio frequency signal through the resonance component.

[0070] Among them, a resonance component can be connected to both ends of the capacitor component to block the radio frequency current in the shimming coil according to the high impedance of the resonance component, so as not to affect the normal function of the shimming coil.

[0071] In Figure 3 the shown embodiment, the function of local shimming is realized in the shimming coil through the transmission circuit and the resonance circuit, and it will not affect the normal function of the shimming coil, effectively saving the number of inductors with larger inductance values in the shimming coil, thereby reducing the volume and structural complexity of the shimming coil, being applicable to a variety of flexible coils, and saving the cost of the shimming coil.

[0072] Since the principle of solving problems by the method in the embodiment of the present application is similar to that of the embodiment of the foregoing shimming coil, the implementation of the method in this embodiment can refer to the description in the embodiment of the foregoing shimming coil, and the repeated parts will not be elaborated.

[0073] An embodiment of the present application also provides a magnetic resonance imaging device, which includes any one of the above shim coils.

[0074] It should be understood that the magnetic resonance imaging device can be various types of medical imaging devices that utilize the characteristics of nuclear spin motion, generate signals after being excited by radio frequency pulses in an external magnetic field, detect the signals with a detector and input them into a computer, and display images on a screen after processing and conversion.

[0075] In summary, the embodiment of the present application provides a shim coil, a design method of the shim coil, and a magnetic resonance imaging device. By connecting a transmission component and a resonance component with a smaller volume in the shim coil, a larger inductive impedance is achieved to block the radio frequency current, and through the action of the direct current, the magnetic field is stabilized without affecting the normal function of the shim coil. It is applicable to various types of shim coils for stabilizing the magnetic field, such as flexible coils, reducing the complexity of the design and structure of the shim coil, thereby reducing the volume of the shim coil and saving the cost of the shim coil.

[0076] In several embodiments provided by the present application, it should be understood that the disclosed device can also be implemented in other ways. The device embodiments described above are only illustrative. For example, the block diagrams in the drawings show the possible architectures, functions, and operations of the devices according to multiple embodiments of the present application. In this regard, each block in the block diagram can represent a module, a program segment, or a part of the code, and the module, program segment, or part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram, as well as the combination of the block diagrams, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0077] In addition, each functional module in various embodiments of the present application can be integrated together to form an independent part, or each module can exist separately, or two or more modules can be integrated to form an independent part.

[0078] When the above-mentioned functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art or a part of this technical solution can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0079] The above are only the embodiments of this application and are not used to limit the protection scope of this application. For those skilled in the art, this application can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this application shall be included in the protection scope of this application. It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0080] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by this application, and all of them should be covered by the protection scope of this application.

[0081] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitations, the elements defined by the statement "including..." do not exclude the existence of additional identical elements in the process, method, article or device including the said elements.

Claims

1. A shimming coil, characterized in that, The shim coil includes: a capacitance component, an amplifier, a transmission component, and a resonance component; The capacitance component is connected to the amplifier; A first end of the transmission component is connected to a power supply circuit, and a second end of the transmission component is connected to both ends of the capacitance component to supply electrical energy and direct current to the shim coil; The resonance component is connected to both ends of the amplifier to block radio frequency signals; Wherein, the transmission component includes: a transmission line and a first capacitor; a first end of the transmission line is connected to the power supply circuit and the first capacitor; a second end of the transmission line is connected to both ends of the capacitance component to supply electrical energy and direct current to the shim coil through the transmission line; A connection point of the transmission line to the first end of the first capacitor is a short circuit point; a connection point of the transmission line to the second end of the capacitance component is an open circuit point to block the radio frequency signals through the short circuit point and the open circuit point; Wherein, the resonance component includes: a second capacitor and a first inductor; the second capacitor is connected in parallel with the first inductor; a first end of the second capacitor and the first inductor is connected to a first end of the amplifier; a second end of the second capacitor and the first inductor is connected to a second end of the amplifier.

2. The shimming coil according to claim 1, wherein, The length of the transmission line is set to: to achieve impedance transformation between the short - circuit point and the open - circuit point through the transmission line, where n is a natural number greater than or equal to 0, and λ is the wavelength.

3. The shimming coil according to any one of claims 1-2, characterized in that, The transmission line is a coaxial line, and the coaxial line includes: an inner shaft and an outer shaft; The inner shaft and the outer shaft are connected through the first capacitor.

4. The shimming coil according to claim 3, wherein, A first end of the inner shaft is connected to a first end of the outer shaft through the first capacitor; A first end of the inner shaft is connected to the power supply circuit; A second end of the inner shaft is connected to a first end of the capacitance component; a second end of the outer shaft is connected to a second end of the capacitance component.

5. The shimming coil according to claim 1, wherein, The second capacitor and the first inductor are resonance devices with dimensions smaller than a preset threshold to block the radio frequency signals.

6. A design method for a shimming coil, characterized in that, The method includes: Connecting a first end of the transmission component to a power supply circuit; Connecting a second end of the transmission component to both ends of the capacitance component of the shim coil to supply electrical energy and direct current to the shim coil through the transmission component; Connecting a resonance component to both ends of the amplifier connected to the capacitance component to block radio frequency signals through the resonance component; Wherein, the transmission component includes: a transmission line and a first capacitor; a first end of the transmission line is connected to the power supply circuit and the first capacitor; a second end of the transmission line is connected to both ends of the capacitance component to supply electrical energy and direct current to the shim coil through the transmission line; A connection point of the transmission line to the first end of the first capacitor is a short circuit point; a connection point of the transmission line to the second end of the capacitance component is an open circuit point to block the radio frequency signals through the short circuit point and the open circuit point; Wherein, the resonance component includes: a second capacitor and a first inductor; the second capacitor is connected in parallel with the first inductor; a first end of the second capacitor and the first inductor is connected to a first end of the amplifier; a second end of the second capacitor and the first inductor is connected to a second end of the amplifier.

7. A magnetic resonance imaging device, characterized in that, The magnetic resonance imaging device includes the shim coil according to any one of claims 1-5.

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