WO2022170746A1

WO2022170746A1 - Magnetic field enhancement device and curved magnetic field enhancement device

Info

Publication number: WO2022170746A1
Application number: PCT/CN2021/111533
Authority: WO
Inventors: 赵乾; 池中海; 孟永钢; 郑卓肇
Original assignee: 清华大学; 北京清华长庚医院
Priority date: 2021-02-10
Filing date: 2021-08-09
Publication date: 2022-08-18

Abstract

A magnetic field enhancement device (20) and a curved magnetic field enhancement device (30). A cylindrical support structure (50) encloses to form a detection space. The cylindrical support structure (50) has a third end (51) and a fourth end (53) that are spaced from and opposite to each other. Multiple magnetic field enhancement assemblies (11, 12) are arranged at intervals on the cylindrical support structure (50) and extend along the direction from the third end (51) to the fourth end (53). A first annular conductive piece (510) is provided on the cylindrical support structure (50) and close to the third end (51). The first annular conductive piece (510) comprises a first opening (501). The first opening (501) is at least partially located between two adjacent magnetic field enhancement assemblies (11, 12). The first annular conductive piece (510) is electrically connected to the portions of the multiple magnetic field enhancement assemblies (11, 12) located at the third end (51). A second annular conductive piece (520) is provided on the cylindrical support structure (50) and close to the fourth end (53). The second annular conductive piece (520) comprises a second opening (502). The second opening (502) is at least partially located between two adjacent magnetic field enhancement assemblies (11, 12). The phase of an induction field is controlled by adjusting the positions of the first opening (501) and the second opening (502), such that the purpose of accurately detecting a detection site is achieved.

Description

Magnetic field enhancement device and curved magnetic field enhancement device

Related applications

This application claims the priority of the Chinese patent application filed on February 10, 2021, the application number is 2021101839292, and the title is "a phase-controllable MRI image enhancement metasurface device", which is hereby incorporated by reference in its entirety; This application also claims the priority of the Chinese patent application filed on February 10, 2021, the application number is 2021101839428, and the title is "A Shaped Curved MRI Image Enhancement Metasurface Device", which is hereby incorporated by reference in its entirety. .

technical field

The present application relates to the technical field of nuclear magnetic resonance imaging, in particular to a magnetic field enhancement device and a curved magnetic field enhancement device.

Background technique

MRI (Magnetic Resonance Imaging, magnetic resonance imaging technology) is a non-invasive detection method, which is an important basic diagnostic technology in the fields of medicine, biology and neuroscience. The signal strength transmitted by traditional MRI equipment mainly depends on the strength of the static magnetic field B0. Using a high magnetic field or even an ultra-high magnetic field system can improve the signal-to-noise ratio, resolution and shorten the scanning time of the image. However, the increase of the static magnetic field strength will bring the following three problems: (1) the non-uniformity of the radio frequency (RF) field will increase, and the tuning difficulty will increase; (2) the heat generation of the human tissue will increase, which will bring safety hazards and patients are prone to Adverse reactions such as dizziness and vomiting: (3) The purchase cost has increased significantly, which is a burden to most small-scale hospitals. Therefore, how to use as small a static magnetic field strength as possible while obtaining high imaging quality has become a crucial issue in MRI technology.

In order to solve the above problems, the prior art provides a cylindrical metasurface device. The cylindrical metasurface device includes a cylindrical support structure and a plurality of magnetic field enhancement components arranged at intervals on the sidewall of the arcuate support structure. A plurality of magnetic field enhancement components are evenly arranged on the sidewall of the cylindrical support structure, so the entire cylindrical metasurface device has isotropic properties. That is, the induced field generated by the cylindrical metasurface device has nothing to do with the placement angle of the metasurface, but is only related to the phase of the incident field (source magnetic field). However, the existing cylindrical metasurface devices cannot perform magnetic field phase control.

SUMMARY OF THE INVENTION

Based on this, it is necessary to provide a magnetic field enhancement device for the above problems.

A magnetic field enhancement device, comprising:

a cylindrical support structure having two spaced opposite third ends and a fourth end; a plurality of magnetic field enhancement components arranged at intervals on the cylindrical support structure and extending along the third end to the fourth end ;as well as

The first annular conductive sheet is disposed on the cylindrical support structure and close to the third end, the first annular conductive sheet has a first opening, and the first opening is at least partially located in two adjacent Between the magnetic field enhancement components, the first annular conductive sheet is electrically connected to the portion of the plurality of magnetic field enhancement components located at the third end; and

The second annular conductive sheet is disposed on the cylindrical support structure and close to the fourth end, the second annular conductive sheet has a second opening, and the second opening is at least partially located in two adjacent Between the magnetic field enhancement components, the second annular conductive sheet is electrically connected to the portion of the plurality of magnetic field enhancement components located at the fourth end.

In the magnetic field enhancement device provided by the embodiment of the present application, when the magnetic field enhancement device is placed in the excitation field of the magnetic resonance system, the direction of the induced field generated by the magnetic field enhancement device is always perpendicular to the cylinder axis, the first The plane formed by the opening and the second opening. A detection site may be placed in the detection space. The phase of the induction field is controlled by adjusting the positions of the first opening and the second opening, so as to achieve the purpose of accurate detection of the detection part. The magnetic field enhancement device with the first opening and the second opening still has good resonance performance, which can enhance the signal field and improve the image quality.

A magnetic field enhancement component includes a flexible support body, a plurality of magnetic field enhancement components, a first conductive sheet and a second conductive sheet. The flexible support body can be bent into a curved surface. The plurality of magnetic field enhancement components are arranged on the flexible support body in parallel and spaced apart. Each of the magnetic field enhancement assemblies includes a first electrical connection end and a second electrical connection end. A structure capacitor and an inductance structure connected in series are connected between the first electrical connection end and the second electrical connection end. The first conductive sheets are respectively connected with the first electrical connection ends of the plurality of magnetic field enhancement components. The second conductive sheets are respectively connected with the second electrical connection ends of the plurality of magnetic field enhancement components. The resonant frequency of the curved magnetic field enhancement device is equal to the target frequency.

The resonance frequency of the curved magnetic field enhancement device provided in the embodiment of the present application is equal to the target frequency. The curved magnetic field enhancement device resonates with the detection part, the magnetic field strength of the detection signal is increased, and the quality of the signal collected by the radio frequency coil is improved. Under the action of external force, the flexible support body can buckling. The flexible support body can be bent into a curved surface, and can be a flat surface. The arc size of the detection curved surface formed by the flexible support body can be adjusted. When the thickness of the patient's abdomen is different, by changing the curvature of the flexible support body, the plurality of magnetic field enhancement components can be fitted to the detection part of the human body, and the gap between the detection part and the curved magnetic field enhancement device can be reduced , the strength of the detection signal is increased, and the signal quality is improved.

Description of drawings

1 is a three-dimensional diagram of a magnetic field enhancement device provided by an embodiment of the present application;

FIG. 2 is an exploded view of a magnetic field enhancement device provided by an embodiment of the present application;

3 is a diagram of a vertical relationship between an induction field and a first opening and a gap provided by an embodiment of the present application;

4 is a schematic diagram of a resonance effect provided by an embodiment of the present application;

5 is an internal magnetic field distribution diagram of a magnetic field enhancement device provided by an embodiment of the present application;

FIG. 6 is a side view of a magnetic field enhancement assembly provided by an embodiment of the present application;

7 is a frequency comparison diagram of a magnetic field enhancement device provided in an embodiment of the present application in a radio frequency transmitting stage and a radio frequency receiving stage;

FIG. 8 is a comparison diagram of the effect of a magnetic field enhancement device provided by an embodiment of the present application;

FIG. 9 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

10 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 11 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 12 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

13 is a perspective view of a magnetic field enhancement assembly provided by an embodiment of the present application;

14 is a top view of a magnetic field enhancement assembly provided by an embodiment of the present application;

15 is a bottom view of a magnetic field enhancement assembly provided by an embodiment of the present application;

FIG. 16 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 17 is a top view of a magnetic field enhancement assembly provided by an embodiment of the present application;

FIG. 18 is a bottom view of a magnetic field enhancement assembly provided by an embodiment of the present application;

19 is an orthographic view of the first electrode layer and the second electrode layer on the first dielectric layer according to an embodiment of the application;

20 is an orthographic view of the first electrode layer and the second electrode layer on the first dielectric layer according to an embodiment of the application;

FIG. 21 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the application;

22 is a frequency comparison diagram of a magnetic field enhancement device provided in an embodiment of the present application in a radio frequency transmitting stage and a radio frequency receiving stage;

FIG. 23 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 24 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 25 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 26 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

27 is a frequency comparison diagram of a magnetic field enhancement device provided in an embodiment of the present application in a radio frequency transmitting stage and a radio frequency receiving stage;

FIG. 28 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the application;

FIG. 29 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the application;

FIG. 30 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 31 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 32 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

33 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 34 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 35 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the application;

FIG. 36 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 37 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the application;

FIG. 38 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 39 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the application;

FIG. 40 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

41 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

42 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

43 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the application;

FIG. 44 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

FIG. 45 is a structural diagram of a magnetic field enhancement component provided by an embodiment of the present application;

46 is a schematic structural diagram of a magnetic field enhancement device provided in an embodiment of the application;

47 is an exploded view of the structure of a magnetic field enhancement device provided in an embodiment of the application;

48 is a magnetic field distribution diagram of a magnetic field enhancement device provided in an embodiment of the application;

FIG. 49 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

FIG. 50 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

FIG. 51 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

52 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

53 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

54 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

55 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

FIG. 56 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

57 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

FIG. 58 is an electrical connection diagram of the magnetic field enhancement component provided in an embodiment of the application;

FIG. 59 is an electrical connection diagram of the magnetic field enhancement component provided in one embodiment of the application.

Description of reference numbers:

The first magnetic field enhancement assembly 11, the second magnetic field enhancement assembly 12, the magnetic field enhancement device 20, the curved magnetic field enhancement device 30, the cylindrical support structure 50, the first tuning circuit 60, the second tuning circuit 70, the first dielectric layer 100, the first Two dielectric layers 831, first electrode layer 110, first sub-electrode layer 111, second sub-electrode layer 112; second electrode layer 120, third electrode layer 130, fourth electrode layer 140, fifth electrode layer 141, Six electrode layer 832, seventh electrode layer 833, first surface 101, second surface 102, third surface 805, first end 103, second end 104, third end 51, fourth end 53, fifth end 881 , the sixth end 882, the first annular conductive sheet 510, the second annular conductive sheet 520, the first opening 501, the second opening 502, the first opening 411, the second opening 412, the third opening 413, the fourth opening 414, Detection space 509, axis 504, central symmetry plane 506, limit structure 530, first structure capacitor 150, second structure capacitor 152, third structure capacitor 153, fourth structure capacitor 306, fifth structure capacitor 303, sixth structure Capacitor 304, switch control circuit 420, first switch control circuit 430, second switch control circuit 450, third switch control circuit 460, first diode 431, second diode 432, third diode 451, Fourth diode 452 , fifth diode 461 , sixth diode 462 , seventh diode 213 , eighth diode 214 , first enhancement MOS transistor 433 , second enhancement MOS transistor 434 , the third enhancement mode MOS tube 453, the fourth enhancement mode MOS tube 454, the fifth enhancement mode MOS tube 463, the sixth enhancement mode MOS tube 464, the seventh enhancement mode MOS tube 235, the eighth enhancement mode MOS tube 236, the external Capacitor 440, first external capacitor 441, second external capacitor 442, third external capacitor 443, fourth external capacitor 444, fifth external capacitor 445, first connection layer 190, second connection layer 191, control circuit 630, A capacitor 223, a second capacitor 224, a first inductor 241, a second inductor 243, a first switch circuit 631, a second switch circuit 650, the second direction a, the first direction b, the first resonant circuit 410, the first power consumption The depletion MOS transistor 231, the second depletion MOS transistor 232, the first curved element 940, the first electrical connection end 911, the second electrical connection end 912, the flexible support body 500, the fixing structure 930, the first fixing member 931, The second fixing member 931 , the first conductive sheet 510 , the second conductive sheet 520 , the output matching circuit 640 , the matching capacitor 641 , the tuning capacitor 642 , the output interface 643 , and the via hole 105 .

Detailed ways

In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application.

The serial numbers themselves, such as "first", "second", etc., for the components herein are only used to distinguish the described objects, and do not have any order or technical meaning. The "connection" and "connection" mentioned in this application, unless otherwise specified, include both direct and indirect connection and connection. In the description of this application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", The orientation or positional relationship indicated by "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description , rather than indicating or implying that the referred device or element must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as a limitation on the present application.

In this application, unless otherwise expressly stated and defined, a first feature "on" or "under" a second feature may be in direct contact with the first and second features, or the first and second features indirectly through an intermediary touch. Also, the first feature being "above", "over" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is level higher than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature has a lower level than the second feature.

Referring to FIG. 1 and FIG. 2 , an embodiment of the present application provides a magnetic field enhancement device 20 . The magnetic field enhancement device 20 includes a cylindrical support structure 50 , a plurality of magnetic field enhancement components, a first annular conductive sheet 510 and a second annular conductive sheet 520 . The cylindrical support structure 50 surrounds and forms a detection space 509 . The cylindrical support structure 50 has two spaced opposite third ends 51 and fourth ends 53 . The plurality of magnetic field enhancement components are disposed at intervals on the cylindrical support structure 50 and extend along the third end 51 to the fourth end 53 . The first annular conductive sheet 510 is disposed on the cylindrical support structure 50 and is close to the third end 51 . The first annular conductive sheet 510 has a first opening 501 . The first opening 501 is at least partially located between two adjacent magnetic field enhancement components. The first annular conductive sheet 510 is electrically connected to the portion of the plurality of magnetic field enhancement components located at the third end 51 . The second annular conductive sheet 520 is disposed on the cylindrical support structure 50 and close to the fourth end 53 . The second annular conductive sheet 520 has a second opening 502 . The second opening 502 is at least partially located between two adjacent first magnetic field enhancing components 11 . The second annular conductive sheet 520 is electrically connected to the portion of the plurality of magnetic field enhancement components located at the fourth end 53 .

The cylindrical support structure 50 surrounds and forms a detection space 509 . The detection space 509 may be used to accommodate the detection site. The to-be-detected part may be an arm, a leg, a waist, or the like. The plurality of first magnetic field enhancement components 11 may be arranged on the cylindrical support structure 50 at equal intervals.

In one embodiment, the cylindrical support structure 50 may have an axis 504 and sidewalls surrounding the axis 504 . A plurality of the magnetic field enhancement components may be arranged on the sidewall of the cylindrical support structure 50 at equal intervals. The distances between the plurality of magnetic field enhancement components are equal to improve the uniformity of the local magnetic field. The side wall of the cylindrical support structure 50 may also be a hollow structure. The plurality of magnetic field enhancement components may be overlapped with the hollow structure.

The plurality of magnetic field enhancement components may be attached to the sidewall of the cylindrical support structure 50, or may be arranged at intervals on the sidewall of the cylindrical support structure 50, as long as the plurality of magnetic field enhancement components are connected to the barrel. The distance between the axes 504 of the shaped support structure 50 can be equal. Equal distances from the plurality of magnetic field enhancement components to the axis 504 of the cylindrical support structure 50 can improve the uniformity of the local magnetic field.

The plurality of magnetic field enhancement components can be used to enhance the magnetic field strength in a local area after the magnetic field enhancement device 20 is placed in the magnetic resonance system, thereby improving the magnetic resonance detection effect. The plurality of magnetic field enhancement components may be in a strip-like structure and extend from the third end 51 to the fourth end 53 .

The first annular conductive sheet 510 and the second annular conductive sheet 520 are respectively disposed on the third end 51 and the fourth end 53 . The first annular conductive sheet 510 and the second annular conductive sheet 520 may both be close to each other around the axis 504 of the cylindrical support structure 50 to form an annular structure. The first opening 501 is formed near the end of the first annular conductive sheet 510 . The second opening 502 is formed near the end of the second annular conductive sheet 520 .

The first opening 501 makes the head and tail ends of the first annular conductive sheet 510 disconnected. The second opening 502 makes the head and tail ends of the second annular conductive sheet 520 not meet. Therefore, when the cylindrical support structure 50 is placed in the excitation field of the magnetic resonance system, the annular structure formed by the first annular conductive sheet 510 and the annular structure formed by the second annular conductive sheet 520 will not form a current loop. The phase of the induced magnetic field of the magnetic field enhancement device 20 can be adjusted by the positions of the first opening 501 and the second opening 502 .

The magnetic field enhancement device 20 is a phase-controllable MRI image enhancement metasurface device. The phase of the induced magnetic field of the phase-controllable MRI image-enhancing metasurface device can be adjusted by the positions of the first opening 501 and the second opening 502 .

The second opening 502 is at least partially located between two adjacent magnetic field enhancement components. The first opening 501 is at least partially located between two adjacent magnetic field enhancement components. Therefore, the second opening 502 or the first opening 501 will not be fully attached to the surface of the magnetic field enhancement component. That is, the head and tail ends of the second annular conductive sheet 520 forming the second opening 502 will not all be attached to the surface of the magnetic field enhancement component. The head and tail ends of the first annular conductive sheet 510 forming the first opening 501 are not completely attached to the surface of the magnetic field enhancement component. Therefore, the head and tail ends of the first annular conductive sheet 510 forming the first opening 501 will not be electrically connected through the magnetic field enhancement component. The head and tail ends of the second annular conductive sheet 520 forming the second opening 502 are not electrically connected through the magnetic field enhancement component. The first annular conductive sheet 510 and the second annular conductive sheet 520 cannot form a conductive path.

In one embodiment, the first annular conductive sheet 510 and the second annular conductive sheet 520 may be made of metal materials such as gold, silver, and copper.

Referring to FIG. 3 , when the magnetic field enhancement device 20 is placed in the excitation field of the magnetic resonance system, the direction of the induced field generated by the magnetic field enhancement device 20 is always perpendicular to the cylinder axis 504 and the first opening 501 and the plane formed by the second opening 502 . The detection site can be placed in the detection space 509 . The phase of the induction field is controlled by adjusting the positions of the first opening 501 and the second opening 502, so as to achieve the purpose of accurate detection of the detection part. Experiments have found that the magnetic field enhancement device 20 with the first opening 501 and the second opening 502 still has good resonance performance, which can enhance the signal field and improve the image quality.

Referring to FIG. 4 , the first annular conductive sheet 510 and the second annular conductive sheet 520 in the magnetic field enhancement device 20 are open-loop structures and the first annular conductive sheet 510 and the second annular conductive sheet Compared with the closed structure of the sheet 520 , the resonance performance is not significantly different, and the resonance performance of the magnetic field enhancement device 20 is not affected.

Referring to FIG. 5 , the magnetic field area inside the magnetic field enhancement device 20 is still highly uniform for the detection effective magnetic field area, and will not cause a change in image contrast.

In one embodiment, the first opening 501 and the second opening 502 are located between two adjacent magnetic field enhancement components. That is, the head and tail ends of the first annular conductive sheet 510 forming the first opening 501 protrude toward the gap between two adjacent magnetic field enhancement components. The head and tail ends of the second annular conductive sheet 520 forming the second opening 502 protrude toward the gap between two adjacent magnetic field enhancement components. Therefore, the area of the magnetic field enhancement component will change in area at the portion of the third end 51 in contact with the first annular conductive sheet 510 and the portion of the fourth end 53 in contact with the second annular conductive sheet 520 . Area mutation causes resistance mutation. The sudden change of resistance causes sudden change of electric field strength, and the induced magnetic field also changes suddenly. The mutated magnetic field can monitor the detection site in a targeted manner, which can improve the detection effect. In the excitation field, the electric field intensity induced by the magnetic field enhancement component at the head and tail ends of the first annular conductive sheet 510 and the second annular conductive sheet 520 increases, so the magnetic field density induced by the electric field increases. The detection effect can be further improved by aligning the region with the increased magnetic field at a specific detection site.

In one embodiment, the cylindrical support structure 50 has a central symmetry plane 506 between the third end 51 and the fourth end 53 . The first opening 501 and the second opening 502 are symmetrical with respect to the central symmetry plane 506 . The central symmetry plane 506 may bisect the cylindrical support structure 50 along a cross-section of the cylindrical support structure 50 . The first opening 501 and the second opening 502 are respectively symmetrical with respect to the central symmetry plane 506 . The line connecting the center of the first opening 501 and the center of the second opening 502 may be parallel to the axis 504 of the cylindrical support structure 50 .

The direction of the induced field generated by the magnetic field enhancement device 20 is always parallel to the central symmetry plane 506 . Therefore, the symmetry of the first opening 501 and the second opening 502 with respect to the central symmetry plane 506 can improve the parallelism of the direction of the induced magnetic field generated by the magnetic field enhancement device 20 with respect to the central symmetry plane 506 . The direction of the induced magnetic field of the magnetic field enhancement device 20 can be precisely adjusted by adjusting the position of the central symmetry plane 506 .

In one embodiment, the arc length corresponding to the first opening 501 and the arc length corresponding to the second opening 502 are smaller than the arc length between two adjacent first magnetic field enhancement components 11 . It can be understood that the first opening 501 is located on the annular track where the first annular conductive sheet 510 is located. The second opening 502 is located on the annular track where the second annular conductive sheet 520 is located. The first opening 501 is formed by removing a part of the first annular conductive sheet 510 located in the annular track. The second opening 502 is formed by removing a part of the ring-shaped track from the second annular conductive sheet 520 . The arc corresponding to the first opening 501 and the arc corresponding to the second opening 502 are located between two adjacent magnetic field enhancement components. That is, the head and tail ends of the first annular conductive sheet 510 forming the first opening 501 protrude toward the gap between two adjacent magnetic field enhancement components, and the protruding distance can be equal to form the second The head and tail ends of the second annular conductive sheet 520 of the opening 502 protrude toward the gap between two adjacent magnetic field enhancement components, and the protruding distances may be equal. The above structure increases the intensity of the electric field induced by the magnetic field enhancement component at the head and tail ends of the first annular conductive sheet 510 and the second annular conductive sheet 520 , so the magnetic field density induced by the electric field increases. The detection effect can be further improved by aligning the area with the increased magnetic field density at a specific detection site.

In one embodiment, the arc length corresponding to the first opening 501 and the arc length corresponding to the second opening 502 are one third to two times the arc length between two adjacent magnetic field enhancement components. one part.

Within this range, the contact area between the two ends of the magnetic field enhancement component and the first annular conductive sheet 510 and the second annular conductive sheet 520 does not change too much, and the power consumption of heat generation can be avoided.

In one embodiment, at the third end 51 , the magnetic field enhancement component is sandwiched between the cylindrical support structure 50 and the first annular conductive sheet 510 . At the fourth end 53 , the magnetic field enhancement component is sandwiched between the cylindrical support structure 50 and the second annular conductive sheet 520 . That is, the first annular conductive sheet 510 and the second annular conductive sheet 520 are sleeved on the side wall of the cylindrical support structure 50 . One end of the magnetic field enhancement assembly is directly attached to the side wall of the cylindrical support structure 50 , and the first annular conductive sheet 510 is located on the side of the magnetic field enhancement assembly away from the cylindrical support structure 50 . The other end of the magnetic field enhancement component is directly attached to the side wall of the cylindrical support structure 50 . The second annular conductive sheet 520 is located on the side of the magnetic field enhancement assembly away from the cylindrical support structure 50 .

The first annular conductive sheet 510 and the second annular conductive sheet 520 press the two ends of the magnetic field enhancement component against the two ends of the cylindrical support structure 50 respectively, that is, they play a fixed role, or they can also play a role of fixing. To the role of electrical connection, the structure is simple, and it is easy to install and disassemble. Referring to FIG. 6 , in one embodiment, the magnetic field enhancement component is the first magnetic field enhancement component 11 . The first magnetic field enhancement component 11 includes a first electrode layer 110 , a second electrode layer 120 and a first dielectric layer 100 . The first dielectric layer 100 includes a first surface 101 and a second surface 102 disposed opposite to each other. The first electrode layer 110 is disposed on the first surface 101 . The first electrode layer 110 covers part of the first surface 101 . The second electrode layer 120 is disposed on the second surface 102 . The second electrode layer 120 covers part of the second surface 102 . The orthographic projection of the first electrode layer 110 on the first dielectric layer 100 overlaps with the orthographic projection of the second electrode layer 120 on the first dielectric layer 100 to form a first structural capacitor 150 .

The fact that the first electrode layer 110 covers part of the first surface 101 means that the first surface 101 and part of the first surface 101 are not covered by the first electrode layer 110 . The fact that the second electrode layer 120 covers a part of the second surface 102 means that the second surface 102 and a part of the second surface 102 are not covered by the second electrode layer 120 . The first electrode layer 110 and the second electrode layer 120 partially overlap on the orthographic projection of the first dielectric layer 100 . The portion of the first electrode layer 110 and the second electrode layer 120 disposed opposite to each other constitutes the first structural capacitor 150 . The portion where the orthographic projections of the first electrode layer 110 and the second electrode layer 120 do not overlap on the first dielectric layer 100 can be used as transmission wires to play the role of equivalent inductance. The first structural capacitor 150 and the equivalent inductance may form an LC oscillating circuit. When the resonant frequency is low, the first structural capacitor 150 with smaller capacitance can reduce the resonant frequency of the magnetic field enhancement device 20 formed by the plurality of the first magnetic field enhancement components 11 to the magnetic resonance system. The frequency of the radio frequency coil can effectively increase the magnetic field strength.

The magnetic field generated by the portion of the first magnetic field enhancement component 11 forming the first structural capacitor 150 is parallel to the plane where the first dielectric layer 100 is located. The magnetic field parallel to the first dielectric layer 100 basically cannot play a role in detection, and belongs to an invalid magnetic field. The magnetic field generated by the part constituting the equivalent inductance in the first magnetic field enhancement component 11 is perpendicular to the first dielectric layer 100 , and can generate an effective magnetic field that acts on the detection area.

In one embodiment, the area occupied by the overlapping portion of the orthographic projection of the first electrode layer 110 on the first dielectric layer 100 and the orthographic projection of the second electrode layer 120 on the first dielectric layer 100 is smaller than Half of the area of the first surface 101 or half of the area of the second surface 102 . Therefore, the area of the first dielectric layer 100 forming the first structural capacitor 150 is less than half of the area of the first dielectric layer 100 . By reducing the area of the first structure capacitor 150, the power consumption of the first structure capacitor 150 can be reduced. The area of the first dielectric layer 100 constituting the first structural capacitor 150 is less than half of the area of the first dielectric layer 100 , which can also reduce the distance between the first magnetic field enhancement component 11 and other cascaded metasurfaces. The degree of coupling significantly improves the performance of the first magnetic field enhancement component 11 .

The first dielectric layer 100 may play a role of supporting the first electrode layer 110 and the second electrode layer 120 . The first dielectric layer 100 may be a rectangular plate-like structure. The first dielectric layer 100 may be an insulating material. In one embodiment, the material of the first dielectric layer 100 may be a glass fiber epoxy resin board. The first electrode layer 110 and the second electrode layer 120 may also be rectangular plate-like structures. Materials of the first electrode layer 110 and the second electrode layer 120 may be made of conductive non-magnetic materials. In one embodiment, the materials of the first electrode layer 110 and the second electrode layer 120 may be metal materials such as gold, silver, and copper.

In one embodiment, the thicknesses of the first electrode layer 110 and the second electrode layer 120 may be equal. The first electrode layer 110 , the second electrode layer 120 and the first dielectric layer 100 are stacked. The planes on which the first electrode layer 110, the second electrode layer 120 and the first dielectric layer 100 are located may be substantially parallel.

Referring to FIG. 6 , an embodiment of the present application provides a first magnetic field enhancement component 11 . The first magnetic field enhancement component 11 includes the first dielectric layer 100 , the first electrode layer 110 , the second electrode layer 120 , the fourth electrode layer 140 and a first switch control circuit 430 . The first dielectric layer 100 includes an opposing first surface 101 and a second surface 102 . The first electrode layer 110 is disposed on the first surface 101 . The second electrode layer 120 and the fourth electrode layer 140 are disposed on the second surface 102 . The first electrode layer 110 and the second electrode layer 120 and the fourth electrode layer 140 respectively have overlapping portions on the orthographic projection of the first dielectric layer 100 . Two ends of the first switch control circuit 430 are respectively connected to the first electrode layer 110 and the second electrode layer 120 . The first switch control circuit 430 is configured to be turned on in the radio frequency transmitting stage and turned off in the radio frequency receiving stage.

The structures and materials of the first dielectric layer 100 , the first electrode layer 110 and the second electrode layer 120 are the same as those of the first dielectric layer 100 , the first electrode layer 110 and all of the above-mentioned embodiments. The structures and materials of the second electrode layer 120 are similar to those described above, which will not be repeated here.

In one embodiment, the thicknesses of the first electrode layer 110 , the second electrode layer 120 and the fourth electrode layer 140 may be equal. The planes on which the first electrode layer 110 , the second electrode layer 120 , the fourth electrode layer 140 and the first dielectric layer 100 are located may be substantially parallel.

The first electrode layer 110 and the second electrode layer 120 have overlapping portions in the orthographic projection of the first dielectric layer 100 . The fourth electrode layer 140 and the first electrode layer 110 have overlapping portions in the orthographic projection of the first dielectric layer 100 . Therefore, in the overlapping portion, the first electrode layer 110 , the second electrode layer and the first dielectric layer 100 may constitute a second structural capacitor 152 . The first electrode layer 110 , the fourth electrode layer 140 and the first dielectric layer 100 may constitute a third structural capacitor 153 . The series connection of two structural capacitors can effectively reduce the load effect and enhance the stability of the resonant frequency of the magnetic field enhancer. In one embodiment, the first electrode layer 110 may completely cover the first dielectric layer 100 .

The first electrode layer 110 , the second electrode layer 120 , and the fourth electrode layer 140 may form an equivalent inductance at the portion of the first dielectric layer 100 that does not overlap. The second structural capacitor 152, the third structural capacitor 153 and the equivalent inductance may constitute an LC oscillation circuit. When the first magnetic field enhancement assembly 11 is placed in the magnetic resonance system, under the action of the excitation field, the resonant frequency of the LC oscillating circuit is adjusted, so that the magnetic field enhancement assembly 20 constituted by a plurality of the first magnetic field enhancement assemblies 11 The resonant frequency is equal to the frequency of the radio frequency coil in the magnetic resonance system. The magnetic field enhancement device 20 formed by the cooperation of a plurality of the first magnetic field enhancement components 11 can play the role of enhancing the radio frequency transmitting field and the radio frequency receiving field.

It can be understood that there are tens to thousands of milliseconds in the time sequence between the radio frequency transmitting phase and the radio frequency receiving phase. The RF power in the RF transmitting stage and the RF receiving stage differs by 3 orders of magnitude. The voltage across the structural capacitance of the RF transmit stage is between a few volts and several hundreds of volts. In the radio frequency receiving stage, the voltage across the structural capacitor is at the level of millivolts.

Both ends of the first switch control circuit 430 are connected between the first electrode layer 110 and the second electrode 120 layer. That is, the first switch control circuit 430 can be connected in parallel with the second structure capacitor 152 . Therefore, when the first switch control circuit 430 is turned on, the first electrode layer 110 and the second electrode layer 120 are electrically connected. When the first switch control circuit 430 is turned off, the first electrode layer 110 and the second electrode layer 120 are disconnected. The turn-on voltage of the first switch control circuit 430 may be greater than 1 volt. That is, when the voltage difference between the two ends of the first electrode layer 110 and the second electrode layer 120 is greater than 1 volt, the first switch control circuit 430 is turned on. When the voltage difference between the first electrode layer 110 and the second electrode layer 120 is less than 1 volt, the first switch control circuit 430 is turned off.

Referring to FIG. 7 , in the radio frequency transmission stage, the first switch control circuit 430 is turned on due to the large voltage difference across the structural capacitor. The first electrode layer 110 and the second electrode layer 120 are electrically connected. At this time, the first electrode layer 110 and the second electrode layer 120 cannot form the second structure capacitor 152 . That is, the magnetic field enhancement components 20 formed by a plurality of the first magnetic field enhancement components 11 do not have a resonance function in the frequency band of interest. Therefore, the first magnetic field enhancement component 11 cannot enhance the radio frequency transmission field.

In the radio frequency receiving stage, the voltage difference between the first electrode layer 110 and the second electrode layer 120 is small, the first switch control circuit 430 is turned off, and the first electrode layer 110 and the second electrode layer 120 are turned off. The two electrode layers are disconnected. At this time, the first electrode layer 110 and the second electrode layer 120 constitute the second structural capacitor 152 . Therefore, the magnetic field enhancement components 20 formed by a plurality of the first magnetic field enhancement components 11 have a good resonance frequency in the radio frequency receiving stage. The first magnetic field enhancement component 11 can enhance the radio frequency transmission field.

Referring to FIG. 8 , an MRI image enhancement effect diagram of the first magnetic field enhancement component 11 provided based on the prior art and the embodiments of the present application.

a is the body coil usually used in the magnetic resonance system, the image signal-to-noise ratio is very low, and the graininess is serious;

b When the first magnetic field enhancement component 11 is not provided with the first switch control circuit 430, many artifacts appear in the formed image, which is caused by the interference of the first magnetic field enhancement component 11 with the radio frequency transmission field;

c The magnetic field enhancement device 20 composed of the plurality of first magnetic field enhancement components 11 provided in the embodiment of the present application has a high image signal-to-noise ratio, a clear and delicate image, and no artifacts are introduced. Therefore, the magnetic field enhancement device 20 constituted by a plurality of the first magnetic field enhancement components 11 has better sequence universality.

In the first magnetic field enhancement component 11 provided in the embodiment of the present application, the first switch control circuit 430 is configured to be turned on in the radio frequency transmission stage and turned off in the radio frequency reception stage. Therefore, in the radio frequency emission stage, the first electrode layer 110 and the second electrode layer 120 are short-circuited, and the second structural capacitor 152 cannot be formed. The first magnetic field enhancement component 11 cannot enhance the radio frequency transmission field, which can effectively reduce the adverse effects of the magnetic field enhancement on the human body, and at the same time can eliminate the artifact of the first magnetic field enhancement component 11 interfering with the image of the radio frequency transmission field.

In one embodiment, the first switch control circuit 430 may also be connected between the first electrode layer 110 and the fourth electrode layer 140 . The first switch control circuit 430 is turned on in the radio frequency transmission phase, so that the first electrode layer 110 and the fourth electrode layer 140 are short-circuited, so that the first magnetic field enhancement component can be further reduced in the radio frequency transmission phase 11 Effects on Magnetic Field Enhancement.

The first switch control circuit 430 is turned off in the radio frequency receiving stage, and at this time, the first electrode layer 110 and the fourth electrode layer 140 can form the third structural capacitor 153 . The cooperation of the third structure capacitor 153 and the second structure capacitor 152 can further improve the effect of magnetic field enhancement.

In one embodiment, one end of the first switch control circuit 430 is connected to the first electrode layer 110 and the second electrode layer 120 having an overlapping portion on the orthographic projection of the first dielectric layer 100 . The other end of the first switch control circuit 430 is connected to the overlapping portion of the second electrode layer 120 and the first electrode layer 110 on the orthographic projection of the first dielectric layer 100 . That is, the position where the first switch control circuit 430 is connected to the first electrode layer 110 constitutes the part of the second structural capacitor 152 . Therefore, it can be avoided that the first switch control circuit 430 is connected to the part of the first electrode layer 110 that does not form the second structure capacitor 152 and the third structure capacitor 153 . The part of the first electrode layer 110 that does not form the second structural capacitor 152 and the third structural capacitor 153 has the function of equivalent inductance, thereby avoiding the generation of the equivalent inductance part formed by the first electrode layer 110 influences.

Referring to FIG. 9 , in one embodiment, the first magnetic field enhancement component 11 further includes a first external capacitor 441 . Two ends of the first external capacitor 441 are respectively connected to the first electrode layer 110 and the second electrode layer 120 . The first external capacitor 441 may be an adjustable capacitor connected in parallel with the first electrode layer 110 and the second electrode layer 120 . The first external capacitor 441 cooperates with the structural capacitor formed by the first electrode layer 110 , the second electrode layer and the first dielectric layer 100 to adjust the magnetic field enhancement device formed by the first magnetic field enhancement component 11 20 resonance performance.

The first external capacitor 441 may be a fixed capacitor or an adjustable capacitor. When the use conditions of the first magnetic field enhancement component 11 are determined, for example, after the frequency of the radio frequency coil is determined, an appropriate fixed capacitance can be selected, so that the fixed capacitance and the first electrode layer 110 , the second electrode layer and the The structure of the first dielectric layer 100 cooperates with capacitance, so that the resonance frequency of the magnetic field enhancement device 20 constituted by the magnetic field enhancement device 10 is equal to the frequency of the radio frequency coil, thereby enhancing the magnetic field. When the use environment of the magnetic field enhancement device 10 is uncertain, for example, the frequency of the radio frequency coil is uncertain, an adjustable capacitor may be used in the magnetic field enhancement device 10 . The resonance frequency of the magnetic field enhancement device 20 formed by the magnetic field enhancement device 10 can be adjusted by adjusting the adjustable capacitance, so that the magnetic field enhancement device 10 is suitable for different environments.

Referring to FIG. 10 , in one embodiment, the first switch control circuit 430 includes a first diode 431 and a second diode 432 . The anode of the first diode 431 is connected to the first electrode layer 110 . The cathode of the first diode 431 is connected to the second electrode layer 120 . The cathode of the second diode 432 is connected to the first electrode layer 110 , and the anode of the second diode 432 is connected to the second electrode layer 120 .

It can be understood that the turn-on voltages of the first diode 431 and the second diode 432 may be 0 volts to 1 volts. In one embodiment, the turn-on voltage of the first diode 431 and the second diode 432 may be 0.8V. The first diode 431 and the second diode 432 are respectively connected in series between the first electrode layer 110 and the second electrode layer, the first diode 431 and the second Diode 432 is connected in reverse.

due to the AC characteristics of radio frequency. The induced voltages generated by the first electrode layer 110 and the second electrode layer 120 are also AC voltages. In the radio frequency emission stage, the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the turn-on voltage of the first diode 431 and the second diode 432 . Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, one of the first diode 431 and the second diode 432 is always turned on. Therefore, the first electrode layer 110 and the second electrode layer are electrically connected.

In the radio frequency receiving stage, the voltage difference between the first electrode layer 110 and the second electrode layer is smaller than the turn-on voltage of the first diode 431 and the second diode 432 . Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, the first diode 431 and the second diode 432 are in a non-conductive state.

Referring to FIG. 11 , in one embodiment, the first switch control circuit 430 includes a first enhancement type MOS transistor 433 and a second enhancement type MOS transistor 434 . The source of the first enhancement type MOS transistor 433 is connected to the second electrode layer 120 . The drain of the first enhancement mode MOS transistor 433 is connected to the first electrode layer 110 . The gate of the first enhancement mode MOS transistor 433 is connected to the first electrode layer 110 . The source of the second enhancement type MOS transistor 434 is connected to the first electrode layer 110 . The drain of the second enhancement type MOS transistor 434 is connected to the second electrode layer. The gate of the second enhancement type MOS transistor 434 is connected to the second electrode layer 120 . That is, the first enhancement type MOS transistor 433 and the second enhancement type MOS transistor 434 are reversely connected.

The first enhancement type MOS transistor 433 and the second enhancement type MOS transistor 434 do not conduct when the gate voltage is less than the threshold voltage, that is, the conductive channel can appear only when the gate voltage is greater than its threshold voltage. .

It can be understood that in the radio frequency emission stage, since the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the first enhancement type MOS transistor 433 and the second enhancement type MOS transistor 434 Turn-on threshold voltage, so no matter which of the first electrode layer 110 and the second electrode layer has a higher voltage, one of the first enhancement type MOS transistor 433 and the second enhancement type MOS transistor 434 is always in On state. Therefore, the first electrode layer 110 and the second electrode layer are electrically connected.

However, in the radio frequency receiving stage, since the voltage difference between the first electrode layer 110 and the second electrode layer is smaller than the conduction threshold of the first enhancement type MOS transistor 433 and the second enhancement type MOS transistor 434 Voltage. Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, the first enhancement type MOS transistor 433 and the second enhancement type MOS transistor 434 are in a non-conducting state.

Referring to FIG. 12 , an embodiment of the present application further provides a first magnetic field enhancement component 11 . The first magnetic field enhancement component 11 includes a first electrode layer 110 , a second electrode layer 120 , a first dielectric layer 100 and a first switch control circuit 430 . The first dielectric layer 100 includes a first surface 101 and a second surface 102 disposed opposite to each other. The first electrode layer 110 is disposed on the first surface 101 , and the first electrode layer 110 covers part of the first surface 101 . The second electrode layer 120 is disposed on the second surface 102 . The second electrode layer 120 covers part of the second surface 102 . The orthographic projection of the first electrode layer 110 on the first dielectric layer 100 overlaps with the orthographic projection of the second electrode layer 120 on the first dielectric layer 100 to form a first structural capacitor 150 . The first switch control circuit 430 is connected between the first electrode layer 110 and the second electrode layer 120 . The first switch control circuit 430 is configured to be turned on in the radio frequency transmitting stage and turned off in the radio frequency receiving stage. The implementation of the first switch control circuit 430 may be the same as or similar to the above-mentioned embodiment, which will not be repeated here.

The fact that the first electrode layer 110 covers part of the first surface 101 means that the first surface 101 and part of the first surface 101 are not covered by the first electrode layer 110 . The fact that the second electrode layer 120 covers a part of the second surface 102 means that the second surface 102 and a part of the second surface 102 are not covered by the second electrode layer 120 . The first electrode layer 110 and the second electrode layer 120 partially overlap on the orthographic projection of the first dielectric layer 100 . The portion of the first electrode layer 110 and the second electrode layer 120 disposed opposite to each other constitutes the first structural capacitor 150 . The portion where the orthographic projections of the first electrode layer 110 and the second electrode layer 120 do not overlap on the first dielectric layer 100 can be used as transmission wires to play the role of equivalent inductance. The first structural capacitor 150 and the equivalent inductance may form an LC oscillating circuit. When the resonant frequency is low, the first structural capacitor 150 can reduce the resonant frequency of the magnetic field enhancement device 20 composed of the first magnetic field enhancement components 11 to the magnetic resonance frequency without a large capacitance value. The operating frequency of the system can effectively increase the magnetic field strength.

In one embodiment, the thicknesses of the first electrode layer 110 and the second electrode layer 120 may be equal. The first electrode layer 110 , the second electrode layer 120 and the first dielectric layer 100 are stacked. The planes on which the first electrode layer 110 , the second electrode layer 120 and the first dielectric layer 100 are located may be substantially parallel.

Referring to FIGS. 13-15 , in one embodiment, the first dielectric layer 100 includes opposing first ends 103 and second ends 104 . The first electrode layer 110 extends from the second end 104 to the first end 103 . The second electrode layer 120 extends from the first end 103 to the second end 104 . The orthographic projection of the first electrode layer 110 on the first dielectric layer 100 overlaps with the orthographic projection of the second electrode layer 120 on the first dielectric layer 100 to form the first structural capacitor 150 . That is, the first electrode layer 110 and the second electrode layer 120 respectively extend from opposite ends of the first dielectric layer 100 to the middle of the first dielectric layer 100 . The first electrode layer 110 and the second electrode layer 120 have overlapping portions on the orthographic projection of the first dielectric layer 100 . The overlapping portion is away from both ends of the first dielectric layer 100 .

In one embodiment, the lengths of the first electrode layer 110 and the second electrode layer 120 are less than three quarters of the length of the first dielectric layer 100 and greater than one fourth of the length of the first dielectric layer 100 one. Within this range, the capacitance value of the first structure capacitor 150 is small, which can reduce power consumption. The length of the effective inductance is relatively long, which can effectively enhance the magnetic field and improve the enhancement effect of the first magnetic field enhancement component 11 on the image signal-to-noise ratio.

The overlapping portion of the orthographic projections of the first electrode layer 110 and the second electrode layer 120 is located in the middle of the first dielectric layer 100 . In the overlapping portion, the first electrode layer 110 , the first dielectric layer 100 and the second electrode layer 120 constitute the first structural capacitor 150 . The first electrode layer 110 and the second electrode layer 120 may constitute transmission wires at the non-overlapping portion of the first dielectric layer 100 to play the role of an inductance. The portion of the first electrode layer 110 and the second electrode layer 120 that are not stacked on the first dielectric layer 100 can also serve as equivalent inductors. The equivalent inductance and the first structural capacitor 150 form an LC oscillating circuit.

The first electrode layer 110 and the second electrode layer 120 are strip-shaped with the same width and have the same extension direction. The extension directions of the first electrode layer 110 and the second electrode layer 120 can be on a straight line, so the width of the first magnetic field enhancement component 11 can be reduced, and the width of the first magnetic field enhancement component 11 can be reduced. volume.

In one embodiment, the first electrode layer 110 and the second electrode layer 120 are located in the middle of the first dielectric layer 100 at the overlapping portion of the orthographic projection of the first dielectric layer 100 . The first structural capacitor 150 is located in the middle of the first dielectric layer 100 .

The middle part of the first dielectric layer 100 may be a part of the first dielectric layer 100 away from the edge of the first dielectric layer 100 . The middle of the first dielectric layer 100 may be the middle of the first dielectric layer 100 , or may be a position to the left or to the right of the middle of the first dielectric layer 100 . The location of the first structural capacitor 150 in the middle of the first dielectric layer 100 can effectively improve the symmetry of the structure of the first magnetic field enhancement component 11, thereby improving the uniformity of the magnetic field.

In one embodiment, the target frequency range of the first magnetic field enhancement component 11 may be 60MHz to 150MHz. In one embodiment, the target frequency range of the first magnetic field enhancement component 11 may be 63.8MHz (corresponding to the main magnetic field BO of the magnetic resonance system being 1.5T) or 128MHz (corresponding to the main magnetic field BO of the magnetic resonance system being 3T). The first dielectric layer 100 may be rectangular. The length of the first dielectric layer 100 may be 250 mm. The length of the overlapping portion of the orthographic projection of the first electrode layer 110 and the second electrode layer 120 on the first dielectric layer 100 may be 20 mm. That is, the length of the first magnetic field enhancement component 11 capable of generating an effective magnetic field is 230 mm. The area of the first magnetic field enhancement component 11 capable of generating an effective magnetic field is significantly increased.

In one embodiment, one end of the first switch control circuit 430 is connected to the first electrode layer 110 in the middle of the first dielectric layer 100 . The other end of the first switch control circuit 430 is connected to the position of the second electrode layer 120 in the middle of the first dielectric layer 100 . That is, both ends of the first switch control circuit 430 are connected to the two pole plates of the first structural capacitor 150 . This connection structure can avoid connecting both ends of the first switch control circuit 430 to the part of the equivalent inductance formed by the first electrode layer 110 and the second electrode layer 120, so it can avoid the first switch control circuit 430 It affects the equivalent inductance part.

Referring to FIGS. 16-18 , in one embodiment, the first magnetic field enhancement component 11 further includes a third electrode layer 130 disposed on the first surface 101 . The third electrode layer 130 extends from the first end 103 to the second end 104 . The third electrode layer 130 covers part of the first surface 101 and is spaced apart from the first electrode layer 110 . The second electrode layer 120 is electrically connected to the third electrode layer 130 .

The thickness of the third electrode layer 130 may be the same as the thickness of the first electrode layer 110 . The third electrode layer 130 may bypass the first dielectric layer 100 and be connected to the second electrode layer 120 . The third electrode layer 130 may also be connected to the second electrode layer 120 through wires passing through the first dielectric layer 100 . When the first magnetic field enhancement component 11 is placed in the excitation field of the magnetic resonance system, the parts of the first electrode layer 110 and the third electrode layer 130 that do not overlap with the second electrode layer 120 may have an inductive effect .

The third electrode layer 130 may extend from the first end 103 of the first dielectric layer 100 to the second end 104 and gradually approach the second electrode layer 120 . The third electrode layer 130 is insulated from the first electrode layer 110 , thus preventing the first structure capacitor 150 formed by the first electrode layer 110 and the second electrode layer 120 from being short-circuited. The first electrode layer 110 and the third electrode layer 130 are disposed on the same side of the first dielectric layer 100 . Therefore, when the first magnetic field enhancement component 11 is installed on the bracket, the first surface 101 is installed toward the side away from the space between them, which can prevent the first electrode layer 110 and the third electrode layer 130 from being damaged. The bracket is damaged.

In one embodiment, the length of the third electrode layer 130 is less than half of the length of the first electrolyte layer 100 . The length of the third electrode layer 130 is greater than one third of the length of the first dielectric layer 100 . Within this range, the equivalent inductance formed by the third electrode layer 130 has a relatively large length, which can effectively increase the area of the first magnetic field enhancement component 11 for generating an effective magnetic field.

In one embodiment, the third electrode layer 130 is strip-shaped, and the extension direction and width of the third electrode layer 130 are the same as those of the first electrode layer 110 . That is, the widths of the third electrode layer 130 and the first electrode layer 110 may be the same, and the third electrode layer 130 and the first electrode layer 110 may be located on the same straight line. The width of the first dielectric layer 100 may be equal to the width of the third electrode layer 130 and the first electrode layer 110 , or slightly larger than the width of the three electrode layer 130 and the first electrode layer 110 . Therefore, the width of the first dielectric layer 100 can be reduced as much as possible.

In one embodiment, the first dielectric layer 100 is provided with via holes 105 . Electrode material is provided in the via hole 105 . The third electrode layer 130 is electrically connected to the second electrode layer 120 through the electrode material. The electrode material may be the same as the material of the third electrode layer 130 and the second electrode layer 120, and thus resistance may be reduced. In one embodiment, the electrode material located in the via hole 105 is integrally formed with the first electrode and the third electrode layer 130 .

In one embodiment, one end of the third electrode layer 130 close to the first electrode layer 110 coincides with the orthographic projection of the via hole 105 . One end of the second electrode layer 120 away from the first electrode layer 110 coincides with the orthographic projection of the via hole 105 . That is, the third electrode layer 130 is in contact with the electrode material located in the via hole 105 and close to the first surface 101 . The second electrode layer 120 is in contact with the electrode material in the via hole 105 near the second surface 102 . Therefore, the third electrode layer 130 and the second electrode layer 120 are electrically connected through the electrode material in the via hole 105 .

Referring to FIG. 19 , in one embodiment, an end of the first electrode layer 110 close to the second electrode layer 120 has a first notch 411 . One end of the second electrode layer 120 close to the first electrode layer 110 has a second notch 412 . The orthographic projections of the first notch 411 and the second notch 412 on the first dielectric layer 100 are coincident. The size of the first notch 411 and the second notch 412 may be the same. The first notch 411 and the second notch 412 .

When the first magnetic field enhancement component 11 is placed in the excitation field of the magnetic resonance system, the overlapping portion of the orthographic projection of the first electrode layer 110 and the second electrode layer 120 on the first dielectric layer 100 The first structural capacitor 150 may be formed. The first notch 411 and the second notch 412 can optimize the local magnetic field distribution, and can improve the detection effect of the specific position of the detection part.

Referring to FIG. 20 , in one embodiment, an end of the first electrode layer 110 close to the second electrode layer 120 has a third notch 413 . The third notch 413 is spaced apart from the first notch 411 . An end of the second electrode layer 120 close to the first electrode layer 110 has a fourth notch 414 . The fourth notch 414 is spaced apart from the second notch 412 . The orthographic projections of the third notch 413 and the fourth notch 414 on the first dielectric layer 100 are coincident. It can be understood that the shape and size of the first notch 411 and the third notch 413 may be the same. The size and shape of the second notch 412 and the fourth notch 414 may be the same. The distance between the first notch 411 and the third notch 413 may be the same. The distance between the second notch 412 and the fourth notch 414 may be the same. The third notch 413 and the fourth notch 414 may be located at the overlapping portion of the orthographic projection of the first electrode layer 110 and the second electrode layer 120 on the first dielectric layer 100 . The third gap 413 and the fourth gap 414 further optimize the local magnetic field distribution and improve the detection effect of the specific position of the detection part. When the first magnetic field enhancement component 11 is the above-mentioned embodiment including the first electrode layer 110 , the second electrode layer 120 and the fourth electrode layer 140 , the first annular conductive sheet 510 and the second electrode layer 120 electrical connection. The second annular conductive sheet 520 is electrically connected to the fourth electrode layer 140 .

When the first magnetic field enhancement component 11 is an embodiment including only the first electrode layer 110 and the second electrode layer 120 , the first annular conductive sheet 510 is electrically connected to the first electrode layer 110 . The second annular conductive sheet 520 is electrically connected to the second electrode layer 120 .

Referring to FIG. 21 , in one embodiment, the first magnetic field enhancement component 11 further includes a second external capacitor 442 , a third external capacitor 443 and a second switch control circuit 450 . One end of the third external capacitor 443 is connected to the second electrode layer 120 . The other end of the third external capacitor 443 is respectively connected to one end of the second external capacitor 442 and one end of the second switch control circuit 450 . The other end of the second external capacitor 442 and the other end of the second switch control circuit 450 are respectively connected to the first electrode layer 110 . The second switch control circuit 450 is configured to be turned on in the radio frequency transmitting stage and turned off in the radio frequency receiving stage.

The first electrode layer 110 , the second electrode layer 120 , and the fourth electrode layer 140 may form an equivalent inductance at the portion of the first dielectric layer 100 that does not overlap. The second structural capacitor 152, the third structural capacitor 153 and the equivalent inductance may constitute an LC oscillation circuit. The resonance frequency of the magnetic field enhancement device 20 formed by the plurality of first magnetic field enhancement components 11 is made equal to the frequency of the radio frequency coil in the magnetic resonance system. When the magnetic field enhancement device 20 with the first magnetic field enhancement components 11 is placed in the magnetic resonance system, under the action of the excitation field, the cooperation of the plurality of the first magnetic field enhancement components 11 can enhance the magnetic field.

The other end of the third external capacitor 443 is respectively connected to one end of the second external capacitor 442 and one end of the second switch control circuit 450 . The other end of the second switch control circuit 450 is connected to the first electrode layer 110 . That is, the other end of the second switch control circuit 450 is connected between the second external capacitor 442 and the third external capacitor 443 . Therefore, when the second switch control circuit 450 is turned on, the second external capacitor 442 is short-circuited. Only the third external capacitor 443 is connected between the first electrode layer 110 and the second electrode layer 120 . When the second switch control circuit 450 is turned off, the second external capacitor 442 and the third external capacitor 443 are connected in series between the first electrode layer 110 and the second electrode layer 120 .

The turn-on voltage of the second switch control circuit 450 may be greater than 1 volt. That is, when the voltage difference between the two ends of the first electrode layer 110 and the second electrode layer 120 is greater than 1 volt, the second switch control circuit 450 is turned on. When the voltage difference between the first electrode layer 110 and the second electrode layer 120 is less than 1 volt, the second switch control circuit 450 is turned off.

In the RF transmission stage, due to the large voltage difference across the second structural capacitor 152, the second switch control circuit 450 is turned on. The second external capacitor 442 is short-circuited. Only the third external capacitor 443 is connected between the first electrode layer 110 and the second electrode layer 120 . By setting the appropriate third external capacitor 443, the degree of detuning of the magnetic field enhancement component 20 formed by the plurality of first magnetic field enhancement components 11 can be reduced or avoided in the radio frequency transmission stage. The third external capacitor 443 can precisely adjust the resonant frequency of the magnetic field enhancement device 20 formed by the plurality of first magnetic field enhancement components 11 , so that the measured area maintains the original magnetic field strength and eliminates the first magnetic field enhancement components 11 Interference with the RF transmit phase. The measured area maintains the original magnetic field strength, which can eliminate the interference of the first magnetic field enhancement assembly 11 to the radio frequency transmission stage, and can effectively improve the clinical performance of the magnetic field enhancement assembly 20 composed of a plurality of the first magnetic field enhancement assemblies 11. practicality. The magnetic field enhancement assembly 20 is made suitable for all sequences of the magnetic resonance system. And can effectively reduce the adverse effects of magnetic field enhancement on the human body.

In the radio frequency receiving stage, the voltage difference across the second structural capacitor 152 is small, and the second switch control circuit 450 is turned off. In the RF receiving stage, the second external capacitor 442 and the third external capacitor 443 are connected in series between the first electrode layer 110 and the second electrode layer 120 .

Referring to FIG. 22 , by setting the second external capacitor 442 and the third external capacitor 443 , the magnetic field enhancement device 20 formed by the plurality of the first magnetic field enhancement components 11 can have a good resonance frequency in the radio frequency receiving stage. Therefore, the magnetic field enhancement device 20 formed by a plurality of the first magnetic field enhancement components 11 can enhance the radio frequency emission field.

The second external capacitor 442 and the third external capacitor 443 may be fixed capacitors or adjustable capacitors. When the use environment of the first magnetic field enhancement component 11 is determined, for example, when the frequency of the radio frequency coil is determined, an appropriate fixed capacitor can be selected so that the resonant frequency of the magnetic field enhancement device 20 formed by the magnetic field enhancement device 10 is the same as the radio frequency. The frequency of the coils is equal, which in turn acts to enhance the magnetic field. When the use environment of the magnetic field enhancement device 10 is uncertain, for example, the frequency of the radio frequency coil is uncertain, the second external capacitor 442 and the third external capacitor 443 may use adjustable capacitors. The resonance frequency of the magnetic field enhancement device 20 formed by the first magnetic field enhancement component 11 can be adjusted by adjusting the adjustable capacitance, so that the magnetic field enhancement device 10 is suitable for different environments.

In the radio frequency transmission stage of the first magnetic field enhancement component 11 provided in this embodiment of the present application, since the voltage difference between the first electrode layer 110 and the second electrode layer 120 is large, the second switch control circuit 450 on. Only the third external capacitor 443 is connected between the first electrode layer 110 and the second electrode layer 120 . The third external capacitor 443 can reduce the detuning degree of the magnetic field enhancement device 20 formed by the plurality of the first magnetic field enhancement components 11 in the radio frequency transmission stage. By setting the third external capacitor 443, in the radio frequency transmission stage, when the first magnetic field enhancement component 11 is used and before the first magnetic field enhancement component 11 is used, the magnetic field strength of the measured area in the magnetic resonance system is the same. Therefore, in the radio frequency transmission stage, the magnetic field strength of the measured area in the magnetic resonance system is kept consistent, that is, the measured area can be kept at the original magnetic field strength, and the interference of the first magnetic field enhancement component 11 to the radio frequency transmission phase can be eliminated. The clinical practicability of the magnetic field enhancement assembly 20 composed of a plurality of the first magnetic field enhancement assemblies 11 can be effectively improved. The magnetic field enhancement assembly 20 is made suitable for all sequences of the magnetic resonance system. It can also effectively reduce the adverse effects of magnetic field enhancement on the human body.

Referring to FIG. 23 , in one embodiment, the second switch control circuit 450 includes a third diode 451 and a fourth diode 452 . The anode of the third diode 451 is connected to the first electrode layer 110 . The cathode of the fourth diode 452 is connected to the first electrode layer 110 . One end of the third external capacitor 443 is connected to the second electrode layer 120 . The other end of the third external capacitor 443 is respectively connected to the cathode of the third diode 451 , the anode of the fourth diode 452 and one end of the second external capacitor 442 . The other end of the second external capacitor 442 is connected to the first electrode layer 110 .

It can be understood that the turn-on voltages of the third diode 451 and the fourth diode 452 may be 0 volts to 1 volts. In one embodiment, the turn-on voltage of the third diode 451 and the fourth diode 452 may be 0.8V. The third diode 451 and the fourth diode 452 are respectively connected in series between the first electrode layer 110 and the second electrode layer, that is, the third diode 451 and the The four diodes 452 are connected in reverse.

due to the AC characteristics of radio frequency. The induced voltages generated by the first electrode layer 110 and the second electrode layer 120 are also AC voltages. In the radio frequency emission stage, the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the turn-on voltage of the third diode 451 and the fourth diode 452 . Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, one of the third diode 451 and the fourth diode 452 is always turned on. Therefore, the second external capacitor 442 is short-circuited.

In the radio frequency receiving stage, the voltage difference between the first electrode layer 110 and the second electrode layer is smaller than the turn-on voltage of the third diode 451 and the fourth diode 452 . Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, the third diode 451 and the fourth diode 452 are both in a non-conducting state, and the radio frequency receiving In the stage, the second external capacitor 442 and the third external capacitor 443 are connected in series between the first electrode layer 110 and the second electrode layer 120 .

Referring to FIG. 24 , in one embodiment, the second switch control circuit 450 further includes a third enhancement type MOS transistor 453 and a fourth enhancement type MOS transistor 454 . The drain of the third enhancement type MOS transistor 453 is connected to the first electrode layer 110 . The gate 453 of the third enhancement mode MOS transistor is connected to the first electrode layer 110 . The source of the fourth enhancement type MOS transistor 454 is connected to the first electrode layer 110 . One end of the third external capacitor 443 is connected to the second electrode layer 120 . The other end of the third external capacitor 443 is respectively connected to the source of the third enhancement MOS transistor 453 , the drain of the fourth enhancement MOS transistor 454 , and the gate of the fourth enhancement MOS transistor 454 . is connected to one end of the second external capacitor 442 . The other end of the second external capacitor 442 is connected to the first electrode layer 110 . That is to say, the third enhancement type MOS transistor 453 and the fourth enhancement type MOS transistor 454 are reversely connected.

The third enhancement type MOS transistor 453 and the fourth enhancement type MOS transistor 454 do not conduct when the gate voltage is less than the threshold voltage, that is, the conductive channel can appear only when the gate voltage is greater than its threshold voltage. .

It can be understood that in the radio frequency emission stage, since the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the third enhancement type MOS transistor 453 and the fourth enhancement type MOS transistor 454 Turn-on threshold voltage, so no matter which of the first electrode layer 110 and the second electrode layer has a higher voltage, one of the third enhancement type MOS transistor 453 and the fourth enhancement type MOS transistor 454 is always in the On state. Therefore, the second external capacitor 442 is short-circuited.

In the radio frequency receiving stage, since the voltage difference between the first electrode layer 110 and the second electrode layer is smaller than the conduction threshold of the third enhancement type MOS transistor 453 and the fourth enhancement type MOS transistor 454 Voltage. Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, the third enhancement type MOS transistor 453 and the fourth enhancement type MOS transistor 454 are in a non-conducting state. That is, in the radio frequency receiving stage, the second external capacitor 442 and the third external capacitor 443 are connected in series between the first electrode layer 110 and the second electrode layer 120 .

The second switch control circuit 450 is turned off in the radio frequency receiving stage, and at this time, the first electrode layer 110 and the fourth electrode layer 140 can form the third structural capacitor 153 . The cooperation of the third structure capacitor 153 and the second structure capacitor 152 can further improve the effect of magnetic field enhancement.

In one embodiment, one end of the second switch control circuit 450 is connected to a position where the first electrode layer 110 and the second electrode layer 120 have overlapping portions on the orthographic projection of the first dielectric layer 100 . The other end of the second switch control circuit 450 is connected to the position where the second electrode layer 120 and the first electrode layer 110 have overlapping portions on the orthographic projection of the first dielectric layer 100 . That is to say, the position where the second switch control circuit 450 is connected to the first electrode layer 110 constitutes the part of the second structural capacitor 152 . Therefore, it can be avoided that the second switch control circuit 450 is connected to the part of the first electrode layer 110 that does not constitute the second structure capacitor 152 and the third structure capacitor 153 . Since the first electrode layer 110 does not constitute the part of the second structure capacitor 152 and the third structure capacitor 153, it has the function of equivalent inductance. Therefore, the above-mentioned position where the second switch control circuit 450 is connected can avoid affecting the part of the equivalent inductance formed by the first electrode layer 110 .

Referring to FIG. 25 , an embodiment of the present application further provides a first magnetic field enhancement component 11 . The first magnetic field enhancement component 11 includes a first electrode layer 110 , a second electrode layer 120 , a first dielectric layer 100 , a second external capacitor 442 , a third external capacitor 443 and a second switch control circuit 450 . The first dielectric layer 100 includes a first surface 101 and a second surface 102 disposed opposite to each other. The first electrode layer 110 is disposed on the first surface 101 , and the first electrode layer 110 covers part of the first surface 101 . The second electrode layer 120 is disposed on the second surface 102 . The second electrode layer 120 covers part of the second surface 102 . The orthographic projection of the first electrode layer 110 on the first dielectric layer 100 overlaps with the orthographic projection of the second electrode layer 120 on the first dielectric layer 100 to form a first structural capacitor 150 . One end of the third external capacitor 443 is connected to the second electrode layer 120 . The other end of the third external capacitor 443 is respectively connected to one end of the second external capacitor 442 and one end of the second switch control circuit 450 . The other end of the second external capacitor 442 and the other end of the second switch control circuit 450 are respectively connected to the first electrode layer 110 . The second switch control circuit 450 is configured to be turned on in the radio frequency transmitting stage and turned off in the radio frequency receiving stage.

It can be understood that the implementation of the second switch control circuit 450 may be the same as or similar to the above-mentioned embodiment, and details are not repeated here.

Referring to FIG. 26 , in one embodiment, the first magnetic field enhancement component 11 further includes a fourth external capacitor 444 , a fifth external capacitor 445 and a third switch control circuit 460 . Two ends of the fourth external capacitor 444 are respectively connected to the first electrode layer 110 and the second electrode layer 120 . One end of the fifth external capacitor 445 is connected to the second electrode layer 120 , the other end of the fifth external capacitor 445 is connected to one end of the third switch control circuit 460 , and the third switch control circuit 460 The other end of the switch is connected to the first electrode layer 110, and the third switch control circuit 460 is configured to be turned on in the radio frequency transmitting stage and disconnected in the radio frequency receiving stage.

The first electrode layer 110 and the second electrode layer 120 have overlapping portions in the orthographic projection of the first dielectric layer 100 . The fourth electrode layer 140 and the first electrode layer 110 have overlapping portions in the orthographic projection of the first dielectric layer 100 . Therefore, in the overlapping portion, the first electrode layer 110 , the second electrode layer 120 and the first dielectric layer 100 may constitute a second structural capacitor 152 . The first electrode layer 110 , the fourth electrode layer 140 and the first dielectric layer 100 may constitute a third structural capacitor 153 .

The first electrode layer 110 , the second electrode layer 120 , and the fourth electrode layer 140 may form an equivalent inductance at the portion of the first dielectric layer 100 that does not overlap. The second structural capacitor 152, the third structural capacitor 153 and the equivalent inductance may constitute an LC oscillation circuit. When the magnetic field enhancement device 20 composed of a plurality of the first magnetic field enhancement components 11 is placed in a magnetic resonance system, under the action of the excitation field, by setting an appropriate LC oscillation circuit, a plurality of the first magnetic field enhancement components 11 are set. The frequency of the magnetic field enhancement device 20 formed by the magnetic field enhancement assembly 11 is equal to that of the radio frequency coil in the magnetic resonance system. The cooperation of a plurality of the first magnetic field enhancement components 11 can play the role of enhancing the radio frequency transmitting field and the radio frequency receiving field.

The fourth external capacitor 444 and the fifth external capacitor 445 may be fixed capacitors or adjustable capacitors. When the use environment of the first magnetic field enhancement component 11 is determined, for example, after the frequency of the radio frequency coil is determined, an appropriate fixed capacitor can be selected so that the resonant frequency of the magnetic field enhancement device 20 formed by the plurality of magnetic field enhancement devices 10 is the same as the resonant frequency of the magnetic field enhancement device 20. The frequencies of the radio frequency coils are equal, thereby enhancing the magnetic field. When the use environment of the magnetic field enhancement device 10 is uncertain, for example, the frequency of the radio frequency coil is uncertain, the fourth external capacitor 444 and the fifth external capacitor 445 may adopt adjustable capacitors. The resonance frequency of the magnetic field enhancement device 20 formed by the first magnetic field enhancement component 11 can be adjusted by adjusting the adjustable capacitance, so that the magnetic field enhancement device 10 is suitable for different environments.

There are tens to thousands of milliseconds in the time sequence between the RF transmit phase and the RF receive phase. The RF power in the RF transmit stage and the RF receive stage differs by 3 orders of magnitude. The voltage across the structural capacitance of the RF transmit stage is between a few volts and several hundreds of volts. In the radio frequency receiving stage, the voltages across the second structural capacitor 152 and the third structural capacitor 153 are at the millivolt level.

The third switch control circuit 460 and the fifth external capacitor 445 are connected in series between the first electrode layer 110 and the second electrode layer 120 . In one embodiment, one end of the third switch control circuit 460 is connected to one end of the fifth external capacitor 445 , and the other end of the third switch control circuit 460 is connected to the first electrode layer 110 . The other end of the fifth external capacitor 445 is connected to the second electrode layer 120 . In one embodiment, one end of the third switch control circuit 460 is connected to one end of the fifth external capacitor 445 . The other end of the third switch control circuit 460 is connected to the second electrode layer 120 . The other end of the fifth external capacitor 445 is connected to the first electrode layer 110 .

Therefore, when the third switch control circuit 460 is turned on, the fifth external capacitor 445 and the fourth external capacitor 444 are connected in parallel to the first electrode layer 110 and the second electrode layer 120 . Compared with two capacitors connected in series, when the total capacitance of the first magnetic field enhancement component 11 is equal, the capacitance of the fifth external capacitor 445 and the fourth external capacitor 444 in parallel is larger. Therefore, the capacitance values of the second structure capacitor 152 and the third structure capacitor 153 can be smaller, and the first magnetic field enhancement component 11 has lower losses.

In the radio frequency transmission stage, the resonance frequency of the magnetic field enhancement device 20 formed by the first magnetic field enhancement component 11 deviates far from the operating frequency of the magnetic resonance system. By connecting the appropriate fifth external capacitor 445 and the fourth external capacitor 444, it can be ensured that in the radio frequency transmission stage of the magnetic resonance system, the measured area maintains the original magnetic field strength, and the first magnetic field enhancement component 11 is eliminated. The interference to the radio frequency transmission stage can effectively improve the clinical practicability of the magnetic field enhancement device 20 composed of a plurality of the first magnetic field enhancement components 11 . The magnetic field enhancement assembly 20 is made suitable for all sequences of the magnetic resonance system.

In the radio frequency transmission stage, the voltage difference between the first electrode layer 110 and the second electrode layer 120 is relatively large, and the third switch control circuit 460 is turned on. The fourth external capacitor 444 and the fifth external capacitor 445 are connected in series between the first electrode layer 110 and the second electrode layer 120 .

In the radio frequency receiving stage, the voltage difference between the first electrode layer 110 and the second electrode layer 120 is small, and the third switch control circuit 460 is turned off. The fourth external capacitor 444 is connected in series between the first electrode layer 110 and the second electrode layer 120 . When the fourth external capacitor 444 is a fixed capacitor, by selecting an appropriate fourth external capacitor 444, the magnetic field enhancement device 20 composed of the magnetic field enhancement devices 20 composed of a plurality of the first magnetic field enhancement components 11 can be The resonance frequency is equal to the frequency of the radio frequency coil, thereby greatly enhancing the radio frequency receiving field and improving the image signal-to-noise ratio. When the fourth external capacitor 444 is an adjustable capacitor, the resonant frequency of the magnetic field enhancement device 20 formed by the first magnetic field enhancement component 11 is equal to the frequency of the radio frequency coil by adjusting the fourth external capacitor 444 .

Referring to FIG. 27 , by setting the fourth external capacitor 444 and the fifth external capacitor 445 appropriately, the magnetic field enhancement device 20 formed by a plurality of the first magnetic field enhancement components 11 can have good performance in the radio frequency receiving stage. Resonant frequency. Finally, the resonant frequency of the magnetic field enhancement device 20 in the receiving stage reaches the working frequency of the magnetic resonance system.

In the first magnetic field enhancement component 11 provided in the embodiment of the present application, the third switch control circuit 460 is configured to be turned on in the radio frequency transmission stage and turned off in the radio frequency reception stage. In the radio frequency transmission stage, the resonant frequency of the magnetic field enhancement device 20 formed by the plurality of the first magnetic field enhancement components 11 deviates far from the operating frequency of the magnetic resonance system. Therefore, by setting the fifth external capacitor 445 and the fourth external capacitor 445 appropriately The external capacitor 444 can ensure that in the radio frequency transmission stage of the magnetic resonance system, the tested area maintains the original magnetic field strength, eliminates the interference of the first magnetic field enhancement component 11 to the radio frequency transmission stage, and can effectively improve the Clinical practicability of the magnetic field enhancement device 20 formed by the first magnetic field enhancement assembly 11 . The magnetic field enhancement assembly 20 is suitable for all sequences of the magnetic resonance system, and the adverse effects on the human body are reduced.

Referring to FIG. 28 , in one embodiment, the first magnetic field enhancement component 11 includes a fifth diode 461 and a sixth diode 462 . The anode of the fifth diode 461 is connected to the first electrode layer 110 . The cathode of the sixth diode 462 is connected to the first electrode layer 110 . One end of the fifth external capacitor 445 is connected to the second electrode layer 120 , and the other end of the fifth external capacitor 445 is connected to the cathode of the fifth diode 461 and the cathode of the sixth diode 462 respectively. anode.

It can be understood that the turn-on voltages of the fifth diode 461 and the sixth diode 462 may be 0 volts to 1 volts. In one embodiment, the turn-on voltage of the fifth diode 461 and the sixth diode 462 may be 0.8V. The fifth diode 461 and the sixth diode 462 are connected in series between the first electrode layer 110 and the second electrode layer 120, respectively, that is, the fifth diode 461 and the The sixth diode 462 is reversely connected.

Due to the alternating current characteristics of radio frequency, the induced voltages generated by the first electrode layer 110 and the second electrode layer 120 are also alternating current voltages. In the radio frequency emission stage, the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the turn-on voltage of the fifth diode 461 and the sixth diode 462 . No matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, one of the fifth diode 461 and the sixth diode 462 is always in an on state. Therefore, in the RF transmission stage, the fourth external capacitor 444 and the fifth external capacitor 445 are connected in parallel between the first electrode layer 110 and the second electrode layer 120 .

In the radio frequency receiving stage, the voltage difference between the first electrode layer 110 and the second electrode layer is smaller than the turn-on voltage of the fifth diode 461 and the sixth diode 462 . Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, the fifth diode 461 and the sixth diode 462 are in a non-conducting state. At this time, in the radio frequency receiving stage, only the fourth external capacitor 444 is connected between the first electrode layer 110 and the second electrode layer 120 .

Referring to FIG. 29 , in one embodiment, the third switch control circuit 460 further includes a fifth enhancement type MOS transistor 463 and a sixth enhancement type MOS transistor 464 . The drain of the fifth enhancement type MOS transistor 463 is connected to the first electrode layer 110 . The gate of the fifth enhancement type MOS transistor 463 is connected to the first electrode layer 110 . The source of the sixth enhancement type MOS transistor 464 is connected to the first electrode layer 110 . One end of the fifth external capacitor 445 is connected to the source of the fifth enhancement mode MOS transistor 463 , and the other end of the fifth external capacitor 445 is connected to the drain of the sixth enhancement mode MOS transistor 464 and the The gate of the sixth enhancement mode MOS transistor 464 is connected.

It can be understood that the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 are non-conductive when the gate voltage is less than the threshold voltage, that is, only when the gate voltage is greater than its threshold voltage, it can appear. Conductive channel.

In the radio frequency emission stage, since the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the conduction distance between the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 threshold voltage, so no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, one of the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 is always turned on state. Therefore, in the RF transmission stage, the fourth external capacitor 444 and the fifth external capacitor 445 are connected in parallel between the first electrode layer 110 and the second electrode layer 120 .

However, in the radio frequency receiving stage, since the voltage difference between the first electrode layer 110 and the second electrode layer is smaller than the conduction threshold of the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 Voltage. Therefore, no matter which of the first electrode layer 110 and the second electrode layer 120 has a higher voltage, the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 are in a non-conducting state. Therefore, in the RF receiving stage, the fourth external capacitor 444 is connected between the first electrode layer 110 and the second electrode layer 120 .

In one embodiment, one end of the third switch control circuit 460 is connected to a position where the first electrode layer 110 and the second electrode layer 120 have overlapping portions on the orthographic projection of the first dielectric layer 100 . The other end of the third switch control circuit 460 is connected to the position where the second electrode layer 120 and the first electrode layer 110 have overlapping portions in the orthographic projection of the first dielectric layer 100 . That is, the position where the third switch control circuit 460 can be connected to the first electrode layer 110 is the part where the first electrode layer 110 forms the second structural capacitor 152 . That is, it is avoided to connect the third switch control circuit 460 to the part of the first electrode layer 110 that does not form the second structure capacitor 152 and the third structure capacitor 153 , thereby avoiding the connection between the first electrode layer 110 and the first electrode layer 110 . The part that constitutes the equivalent inductance has an effect.

Referring to FIG. 30 , the embodiment of the present application further provides a first magnetic field enhancement component 11 . The first magnetic field enhancement component 11 includes a first electrode layer 110 , a second electrode layer 120 , a first dielectric layer 100 , the fourth external capacitor 444 , the fifth external capacitor 445 and the third switch control circuit 460. The first dielectric layer 100 includes a first surface 101 and a second surface 102 disposed opposite to each other. The first electrode layer 110 is disposed on the first surface 101 , and the first electrode layer 110 covers part of the first surface 101 . The second electrode layer 120 is disposed on the second surface 102 . The second electrode layer 120 covers part of the second surface 102 . The orthographic projection of the first electrode layer 110 on the first dielectric layer 100 overlaps with the orthographic projection of the second electrode layer 120 on the first dielectric layer 100 to form a first structural capacitor 150 . Two ends of the fourth external capacitor 444 are respectively connected to the first electrode layer 110 and the second electrode layer 120 . The fifth external capacitor 445 and the third switch control circuit 460 are connected in series between the first electrode layer 110 and the second electrode layer 120 . The third switch control circuit 460 is configured to be turned on in the radio frequency transmitting stage and turned off in the radio frequency receiving stage. The implementation manner of the third switch control circuit 460 may be the same as or similar to the above-mentioned embodiment, which will not be repeated here.

Referring to FIG. 31, an embodiment of the present application provides a first magnetic field enhancement component 11, including a first dielectric layer 100, a first electrode layer 110, a second electrode layer 120, a third electrode layer 130, a fourth electrode layer 140 and the control circuit 630 .

The first dielectric layer 100 has opposing first ends 103 and second ends 104 . The first dielectric layer 100 includes a first surface 101 and a second surface 102 that are opposed. The first electrode layer 110 and the third electrode layer 130 are disposed close to the first end 103 . The second electrode layer 120 and the fourth electrode layer 140 are disposed close to the second end 104 . The orthographic projection of the first electrode layer 110 on the first dielectric layer 100 partially overlaps the orthographic projection of the third electrode layer 130 on the first dielectric layer 100 . The first electrode layer 110 , the first dielectric layer 100 and the third electrode layer 130 constitute a fourth structural capacitor 306 . The orthographic projection of the second electrode layer 120 on the first dielectric layer 100 partially overlaps the orthographic projection of the fourth electrode layer 140 on the first dielectric layer 100 . The second electrode layer 120 , the first dielectric layer 100 and the fourth electrode layer 140 constitute a fifth structural capacitor 303 .

The control circuit 630 includes a first capacitor 223 , a first inductor 241 and a first switch circuit 631 . One end of the first capacitor 223 is connected to the first electrode layer 110 . The other end of the first capacitor 223 is connected to the second electrode layer 120 . One end of the first inductor 241 is connected to the second electrode layer 120 . The first switch circuit 631 is connected between the other end of the first inductor 241 and the first electrode layer 110 . The first switch circuit 631 is configured to be turned off during the radio frequency receiving stage. The first switch circuit 631 is also configured to be turned on during the RF transmission stage, so that the control circuit 630 is in a high-impedance state.

The first switch circuit 631 in the first magnetic field enhancement component 11 provided in the embodiment of the present application is configured to be disconnected during the radio frequency receiving stage. The fourth structure capacitor 306 and the fifth structure capacitor 303 are connected through the first capacitor 223 . The first switch circuit 631 and the first inductor 241 do not participate in circuit conduction. The first switch circuit 631 is also configured to be turned on during the radio frequency transmission stage, and the first capacitor 223 is connected in parallel with the first inductor 241, so that the control circuit 630 is in a high-impedance state. There is an open circuit between the fourth structure capacitor 306 and the fifth structure capacitor 303 . During the RF signal transmission stage, there is almost no current flow between the fourth structural capacitor 306 and the fifth structural capacitor 303, and the magnetic field generated by the first magnetic field enhancement component 11 is weakened, thereby reducing the first magnetic field enhancement The influence of the component 11 on the magnetic field in the transmitting stage of the radio frequency signal can reduce the artifacts of the detected image and improve the definition of the detected image.

The first switch circuit 631 may be controlled by a control circuit. In one embodiment, the first switch circuit 631 includes a switch element and a control terminal. One end of the switching element is connected to the end of the first inductor 241 away from the second electrode layer 120 . The other end of the switching element is connected to the first electrode layer 110 . The control terminal is connected with an external control device. The control terminal is used for receiving closing and opening commands. In the radio frequency transmission stage, the control device outputs a closing command to the control terminal. When the control terminal receives a closing command, the first inductor 241 is connected to the first electrode layer 110 . The first inductor 241 is connected in parallel with the first capacitor 223 and is in a high resistance state; there is almost no current flow between the first electrode layer 110 and the second electrode layer 120 .

In the radio frequency receiving stage, the control device outputs a closing command to the control terminal. When the control terminal receives a disconnection command, the first inductor 241 is disconnected from the first electrode layer 110 . The first electrode layer 110 , the first capacitor 223 and the second electrode layer 120 are connected in series to form a part of a resonant circuit. The magnetic field enhancement device 20 constituted by a plurality of the magnetic field enhancement components restores resonance, and greatly enhances the radio frequency receiving field.

In one embodiment, the first switch circuit 631 includes a seventh diode 213 and an eighth diode 214 . The anode of the seventh diode 213 is connected to the first electrode layer 110 . The cathode of the seventh diode 213 is connected to the other end of the first inductor 241 . The anode of the eighth diode 214 is connected to the other end of the first inductor 241 , and the cathode of the eighth diode 214 is connected to the first electrode layer 110 .

The first magnetic field enhancement component 11 is applied to the MRI system to enhance the magnetic field strength of the human body feedback signal in the radio frequency receiving stage. In the radio frequency transmitting stage of the MRI system, the magnetic field energy in the transmitting stage is more than 1000 times the magnetic field energy in the receiving stage. The induced voltage of the first magnetic field enhancement component 11 in the emission stage is between several tens of volts to several hundreds of volts. The induced voltage of the first magnetic field enhancement component 11 in the receiving stage is less than 1V.

The seventh diode 213 and the eighth diode 214 are connected in antiparallel. In the radio frequency transmission stage, the radio frequency coil transmits the radio frequency transmission signal, and the field strength of the magnetic field is relatively large. The induced voltage generated by the first magnetic field enhancement component 11 is relatively large. The positive and negative voltages applied across the seventh diode 213 and the eighth diode 214 alternate. The loaded voltage exceeds the turn-on voltages of the seventh diode 213 and the eighth diode 214, and the seventh diode 213 and the eighth diode 214 are turned on. The first capacitor 223 is connected in parallel with the first inductor 241, so that the control circuit 630 is in a high resistance state. In the radio frequency signal transmission stage, there is almost no current flow between the fourth structure capacitor 306 and the fifth structure capacitor 303, the magnetic field generated by the first magnetic field enhancement component 11 is weakened, and the first magnetic field enhancement component is reduced. 11. The influence of the magnetic field in the radio frequency signal transmission stage, thereby reducing the artifacts of the detection image and improving the clarity of the detection image.

In the RF receiving stage, the detection part transmits a feedback signal, and the field strength of the magnetic field is small. The induced voltage generated by the first magnetic field enhancement component 11 is relatively small. The loaded voltage cannot reach the turn-on voltages of the seventh diode 213 and the eighth diode 214, and the seventh diode 213 and the eighth diode 214 are non-conductive. The fourth structural capacitor 306 and the fifth structural capacitor 303 are connected through the first capacitor 223, and the magnetic field enhancement device 20 composed of the plurality of the first magnetic field enhancement components 11 is in a resonant state and plays the role of enhancing the magnetic field .

In one embodiment, the turn-on voltages of the seventh diode 213 and the eighth diode 214 are both between 0 and 1V. In one embodiment, the turn-on voltages of the seventh diode 213 and the eighth diode 214 are the same, so that the magnetic field enhancement device 20 continuously increases the magnetic field strength during the radio frequency receiving stage, thereby improving the feedback signal stability. In one embodiment, the turn-on voltage of the seventh diode 213 and the eighth diode 214 is 0.8V.

In one embodiment, the seventh diode 213 and the eighth diode 214 are of the same model, and the voltage drop after the seventh diode 213 and the eighth diode 214 are turned on The same, so that the increase of the magnetic field strength of the magnetic field enhancement device 20 in the radio frequency receiving stage is the same, and the stability of the feedback signal is further improved.

Please also refer to FIG. 32 , in one embodiment, the first switch circuit 631 includes a seventh enhancement type MOS transistor 235 and an eighth enhancement type MOS transistor 236 . The drain and the gate of the seventh enhancement mode MOS transistor 235 are respectively connected to one end of the first inductor 241 away from the second electrode layer 120 . The source of the seventh enhancement mode MOS transistor 235 is connected to the first electrode layer 110 . The drain and gate of the eighth enhancement mode MOS transistor 236 are respectively connected to the first electrode layer 110 . The source of the eighth enhancement mode MOS transistor 236 is connected to one end of the first inductor 241 away from the second electrode layer 120 .

The seventh enhancement type MOS transistor 235 and the eighth enhancement type MOS transistor 236 are connected in anti-parallel. In the radio frequency transmission stage, the radio frequency coil transmits the radio frequency transmission signal, and the field strength of the magnetic field is relatively large. The induced voltage generated by the first magnetic field enhancement component 11 is relatively large. The positive and negative voltages applied to both ends of the seventh enhancement type MOS transistor 235 and the eighth enhancement type MOS transistor 236 alternate. When the loaded voltage exceeds the channel turn-on voltage of the seventh enhancement MOS transistor 235 and the eighth enhancement MOS transistor 236, the source and drain of the seventh enhancement MOS transistor 235 are turned on and the first enhancement MOS transistor 235 is turned on. The sources and drains of the eight enhancement mode MOS transistors 236 are alternately turned on. The first capacitor 223 is connected in parallel with the first inductor 241, so that the control circuit 630 is in a high resistance state. In the radio frequency signal transmission stage, there is almost no current flow between the fourth structure capacitor 306 and the fifth structure capacitor 303, the magnetic field generated by the first magnetic field enhancement component 11 is weakened, and the first magnetic field enhancement component is reduced. 11. The influence of the magnetic field in the radio frequency signal transmission stage, thereby reducing the artifacts of the detection image and improving the clarity of the detection image.

In the RF receiving stage, the detection part transmits a feedback signal, and the field strength of the magnetic field is small. The induced voltage generated by the first magnetic field enhancement component 11 is relatively small. The loaded voltage cannot reach the channel turn-on voltage of the seventh enhancement MOS transistor 235 and the eighth enhancement MOS transistor 236, the source and drain of the seventh enhancement MOS transistor 235 are turned on and the The source and drain of the eight enhancement mode MOS transistors 236 are not conductive. The fourth structural capacitor 306 and the fifth structural capacitor 303 are connected through the first capacitor 223, and the magnetic field enhancement device 20 composed of the plurality of the first magnetic field enhancement components 11 is in a resonant state and plays the role of enhancing the magnetic field .

In one embodiment, the channel turn-on voltages of the seventh enhancement type MOS transistor 235 and the eighth enhancement type MOS transistor 236 are both between 0 and 1V, and the seventh enhancement type MOS transistor 235 and the The channel conduction voltage of the eighth enhancement mode MOS transistor 236 is the same, so that the magnetic field enhancement device 20 can stably enhance the magnetic field in the radio frequency receiving stage, and the feedback signal can be stably output. In one embodiment, the channel turn-on voltage of the seventh enhancement type MOS transistor 235 and the eighth enhancement type MOS transistor 236 is 0.8V.

Please also refer to FIG. 33 , in one embodiment, the first electrode layer 110 further includes a first sub-electrode layer 111 and a first connection layer 190 . The first sub-electrode layer 111 is connected to the first connection layer 190 . The first connection layer 190 is disposed close to the second electrode layer 120 . The orthographic projection of the first sub-electrode layer 111 on the first dielectric layer 100 partially overlaps the orthographic projection of the third electrode layer 130 on the first dielectric layer 100 . One end of the first capacitor 223 is connected to one end of the first connection layer 190 close to the first sub-electrode layer 111 . The other end of the first capacitor 223 is connected to the second electrode layer 120 . The first switch circuit 631 is connected between one end of the first connection layer 190 away from the first sub-electrode layer 111 and the second electrode layer 120 . The first connection layer 190 constitutes the first inductor 241 .

A circuit in which the first switch circuit 631 is connected in series with the first connection layer 190 is connected in parallel with the first capacitor 223 . The control circuit 630 is connected in series between the first electrode layer 110 and the second electrode layer 120 . The first sub-electrode layer 111 and the first connection layer 190 may be formed by spraying. The first sub-electrode layer 111 and the first connection layer 190 are laid on the same layer, which saves the process. The first sub-electrode layer 111 is used to form a part of the structural capacitance. The first connection layer 190 is used to form a structural inductance, no external inductance is required, and cost is saved.

Please also refer to FIG. 34 , in one embodiment, the width of the first connection layer 190 is smaller than that of the first sub-electrode layer 111 . The first magnetic field enhancement component 11 covers the detection part, and enhances the magnetic field of the feedback signal of the detection part by means of resonance. Since the width of the first connection layer 190 in the first magnetic field enhancement component 11 is smaller than the width of the first sub-electrode layer 111, the area of the detection portion covered by the first electrode layer 110 is reduced, so The shielding effect of the first electrode layer 110 is weakened, and the transmission capability of the feedback signal is enhanced. The radio frequency coil is easier to receive the feedback signal, thereby improving the quality of the received signal and the quality of the image formed after the signal is processed. In addition, when a plurality of the first magnetic field enhancement components 11 are used together, the relative overlapping area between the first connection layers 190 in the different first magnetic field enhancement components 11 is reduced, and the different first magnetic field enhancement components The stray capacitance formed by the first connection layer 190 and the air in 11 is reduced, the coupling effect is reduced, and the signal quality is improved.

Please refer to FIG. 35 together. In one embodiment, the first magnetic field enhancement component 11 further includes a fifth electrode layer 141 . The fifth electrode layer 141 is disposed on the second surface 102 and is disposed between the third electrode layer 130 and the fourth electrode layer 140 at intervals. The orthographic projection of the fifth electrode layer 141 on the first dielectric layer 100 partially overlaps the orthographic projection of the first electrode layer 110 on the first dielectric layer 100 . The fifth electrode layer 141 , the first dielectric layer 100 and the first electrode layer 110 constitute the sixth structure capacitor 304 . The orthographic projection of the fifth electrode layer 141 on the first dielectric layer 100 partially overlaps the orthographic projection of the second electrode layer 120 on the first dielectric layer 100 . The fifth electrode layer 141 , the first dielectric layer 100 and the second electrode layer 120 constitute the first capacitor 223 .

The fifth structure capacitor 303 , the first capacitor 223 , the sixth structure capacitor 304 and the fourth structure capacitor 306 are connected in series. The other non-capacitive structural parts of the first electrode layer 110 and the second electrode layer 120 are used for conduction. A first circuit is formed by connecting the first switch circuit 631 and the first inductor 241 in series. The part of the fifth electrode layer 141 opposite to the second electrode layer 120 and the sixth structure capacitor 304 are connected in series to form a second circuit. The first circuit and the second circuit are connected in parallel to form the control circuit 630 . The control circuit 630 uses laid electrodes to form a capacitor, and does not need to use an external capacitor, which saves costs.

Please refer to FIG. 36 together. In one embodiment, the control circuit 630 further includes a second inductor 243 . The first inductor 241 , the first switch circuit 631 and the second inductor 243 are connected in series in sequence. One end of the second inductor 243 is connected to the first electrode layer 110 . The other end of the second inductor 243 is connected to the first switch circuit 631 . The first inductance 241 and the second inductance 243 are respectively connected to two ends of the first switch circuit 631 to increase the symmetry of the structure of the first magnetic field enhancement component 11, thereby increasing the first magnetic field enhancement component The symmetry of the magnetic field of 11 reduces the distortion caused by the inconsistency of magnetic field enhancement.

Please refer to FIG. 37 together. In one embodiment, the control circuit 630 further includes a second capacitor 224 . The second capacitor 224 is connected between the first capacitor 223 and the first electrode layer 110 . The second capacitor 224 is connected in series with the first capacitor 223 . The second capacitor 224 is used to reduce the partial pressure of the first capacitor 223 , improve the ability of the first magnetic field enhancement component 11 to resist a strong magnetic field, and reduce the probability of the first capacitor 223 being broken down.

In one embodiment, the capacitance values of the fourth structure capacitor 306 , the fifth structure capacitor 303 , the first capacitor 223 and the second capacitor 224 are all equal. In the radio frequency receiving stage, the partial voltages on the fourth structure capacitor 306, the fifth structure capacitor 303, the first capacitor 223 and the second capacitor 224 are the same, which improves the uniformity of the magnetic field and reduces the inconsistency of the magnetic field enhancement. resulting in distortion and improved image quality.

Referring to FIGS. 38 and 39 , an embodiment of the present application provides a first magnetic field enhancement component 11 , which includes a first dielectric layer 100 , a first electrode layer 110 , a second electrode layer 120 and a third electrode layer 130 . The first dielectric layer 100 has opposing first ends 103 and second ends 104 . The first dielectric layer 100 also includes opposing first and

second surfaces

101 and 102 .

The first electrode layer 110 is disposed on the first surface 101 . The first electrode layer 110 extends from the first end 103 to the second end 104 . The first electrode layer 110 includes a first sub-electrode layer 111 , a second sub-electrode layer 112 and a first connection layer 190 . The widths of the first sub-electrode layer 111 and the second sub-electrode layer 112 are the same. The first sub-electrode layer 111 and the second sub-electrode layer 112 are relatively spaced apart. One end of the first connection layer 190 is connected to the first sub-electrode layer 111 . The other end of the first connection layer 190 is connected to the second sub-electrode layer 112 . The width of the first connection layer 190 is smaller than the width of the first sub-electrode layer 111 or the second sub-electrode layer 112 .

The second electrode layer 120 and the third electrode layer 130 are disposed on the second surface 102 with relative intervals. The orthographic projection of the second electrode layer 120 on the first dielectric layer 100 partially overlaps the orthographic projection of the first sub-electrode layer 111 on the first dielectric layer 100 . The second electrode layer 120 , the first dielectric layer 100 and the first sub-electrode layer 111 constitute a fourth structural capacitor 306 . The orthographic projection of the third electrode layer 130 on the first dielectric layer 100 partially overlaps the orthographic projection of the second sub-electrode layer 112 on the first dielectric layer 100 . The third electrode layer 130, the first dielectric layer 100 and the second sub-electrode layer 112 constitute a fifth structural capacitor 303.

The fourth structure capacitor 306 and the fifth structure capacitor 303 are connected through the first connection layer 190 to form a resonance circuit. When the first magnetic field enhancing component 11 covers the detection part, the magnetic field of the feedback signal of the detection part is enhanced by way of resonance. In the first magnetic field enhancement component 11 provided in the embodiment of the present application, the width of the first connection layer 190 is smaller than the width of the first sub-electrode layer 111 . The area of the detection portion covered by the first electrode layer 110 is reduced, the shielding effect of the first electrode layer 110 is weakened, and the transmission capability of the feedback signal is enhanced. The radio frequency coil is easier to receive the feedback signal, thereby improving the quality of the received signal and the quality of the image formed after the signal is processed.

In addition, when a plurality of the first magnetic field enhancement components 11 are used together, the relative overlapping area between the first connection layers 190 in the different first magnetic field enhancement components 11 is reduced, and the different first magnetic field enhancement components The stray capacitance formed by the first connection layer 190 and the air in 11 is reduced, the coupling effect is reduced, and the signal quality is improved.

The first dielectric layer 100 may play a role of supporting the first electrode layer 110 , the second electrode layer 120 and the third electrode layer 130 . The first dielectric layer 100 may be an insulating material. The first dielectric layer 100 may be a rectangular plate-like structure. The first dielectric layer 100 may be an insulating material. In one embodiment, the material of the first dielectric layer 100 may be a glass fiber epoxy resin board. Materials of the first electrode layer 110 , the second electrode layer 120 and the third electrode layer 130 may be made of conductive non-magnetic materials. In one embodiment, the materials of the first electrode layer 110 , the second electrode layer 120 and the third electrode layer 130 may be metal materials such as gold, silver, and copper. The first electrode layer 110 , the second electrode layer 120 and the third electrode layer 130 formed of the above-mentioned materials have good electrical conductivity and are easy to manufacture.

In one embodiment, the first sub-electrode layer 111 , the second sub-electrode layer 112 and the first connection layer 190 are laid on the same layer, which reduces the process and improves the work efficiency.

In one embodiment, the length and width of the first sub-electrode layer 111 and the second sub-electrode layer 112 are the same. The orthographic projection of the second electrode layer 120 on the first dielectric layer 100 overlaps with the orthographic projection of the first sub-electrode layer 111 on the first dielectric layer 100 . The orthographic projection of the third electrode layer 130 on the first dielectric layer 100 overlaps with the orthographic projection of the second sub-electrode layer 112 on the first dielectric layer 100 . The capacitances of the fourth structure capacitor 306 and the fifth structure capacitor 303 are equal in size and have the same capacitance value. The first magnetic field enhancement component 11 has high symmetry. The first magnetic field enhancement component 11 has a better enhancement effect on the feedback signal magnetic field. The enhanced magnetic field of the feedback signal has higher uniformity, so that the feedback signal has higher quality.

In one embodiment, the length of the first dielectric layer 100 ranges from 100 mm to 500 mm. In one embodiment, the length of the first dielectric layer 100 is 250 mm. The width of the first dielectric layer 100 is 10 mm to 30 mm. In one embodiment, the width of the first dielectric layer 100 is 15 mm. In one embodiment, the thickness of the first dielectric layer 100 is 0.2 mm to 2 mm. In one embodiment, the thickness of the first dielectric layer 100 is 0.51 mm.

The first direction b is from the first end 103 to the second end 104 . The first direction a is perpendicular to the second direction b. The width direction of the second sub-electrode layer 112 is the second direction a.

In one embodiment, the electrical loss ratio of the first connection layer 190 is less than 1/2 of the overall electrical loss of the first magnetic field enhancement component 11 . The electrical loss of the first connection layer 190 is small, and the heat generation of the first magnetic field enhancement component 11 is small. The energy of the first magnetic field enhancement component 11 is mainly used to generate a magnetic field, and the enhancement effect of the magnetic field is better in the receiving stage.

In one embodiment, the width of the first connection layer 190 is 1/5 to 1/2 of the width of the first sub-electrode layer 111 . When the width of the first connection layer 190 is 1/5 to 1/2 of the width of the first sub-electrode layer 111 , the electrical power of the first connection layer 190 in the first magnetic field enhancement component 11 can be guaranteed. The loss ratio is less than 1/2 of the overall electrical loss. The electrical loss of the first connection layer 190 is small, and the heat generated by the first magnetic field enhancement component 11 is small. The energy of the first magnetic field enhancement component 11 is mainly used to generate a magnetic field, and the enhancement effect of the magnetic field is better in the receiving stage.

In one embodiment, the width of the first sub-electrode layer 111 and the second sub-electrode layer 112 is 1 mm to 30 mm. The first connection layer 190 is 1 mm to 15 mm. In one embodiment, the width of the first sub-electrode layer 111 and the second sub-electrode layer 112 is 15 mm, and the width of the first connection layer 190 is 4 mm.

Referring to FIG. 40 together, in one embodiment, the included angle between the extending direction of the first connection layer 190 and the first direction b is an acute angle or an obtuse angle. The first direction b is directed from the first end 103 to the second end 104 . When the magnetic field enhancement device 20 includes a cylindrical support structure 50 , a first annular conductive sheet 510 , a second annular conductive sheet 520 and a plurality of the first magnetic field enhancement components 11 , the cylindrical support structure 50 is a cylindrical structure , a plurality of the first magnetic field enhancement components 11 are arranged in parallel on the cylindrical support structure 50 at intervals. A plurality of the first magnetic field enhancement components 11 are connected in parallel. In the magnetic field enhancement device 20 , the first connection layers 190 in the two opposite first magnetic field enhancement components 11 are arranged in a staggered manner, and the overlapping portion in parallel is reduced. The stray capacitance formed between the first connection layer 190 and the air in the two opposite first magnetic field enhancement components 11 is reduced, the coupling effect is reduced, and the signal quality is improved.

Please also refer to FIG. 41 , in one embodiment, the intersection of the sidewall of the first connection layer 190 and the sidewall of the first sub-electrode layer 111 or the second sub-electrode 112 is provided with an arc-shaped inverted horn. Current flows in the first sub-electrode layer 111 , the first connection layer 190 and the second sub-electrode layer 112 . The width of the first connection layer 190 is smaller than the width of the first sub-electrode layer 112 . The current is collected at the connection between the first sub-electrode layer 111 and the first connection layer 190, and the current density increases. An arc-shaped chamfer is provided at the intersection of the sidewall of the first connection layer 190 and the sidewall of the first sub-electrode layer 111 , so that the first connection layer 190 and the first sub-electrode layer 111 pass through the horn The shape structure is connected, the sudden change of the current density is slowed down, and the current density at the intersection of the sidewall of the first connection layer 190 and the sidewall of the first sub-electrode layer 111 is reduced. The current density at the connection between the first connection layer 190 and the first sub-electrode layer 111 is reduced, the heat generation is reduced, and the service life of the first magnetic field enhancement component 11 is increased.

The current is collected at the connection between the second sub-electrode layer 112 and the first connection layer 190, and the current density increases. An arc-shaped chamfer is provided at the intersection of the sidewall of the first connection layer 190 and the sidewall of the second sub-electrode layer 112 , so that the first connection layer 190 and the second sub-electrode layer 112 are connected at the intersection A flared structure is formed. The horn-shaped structure formed at the connection between the first connection layer 190 and the second sub-electrode layer 112 can slow down the sudden change of the current density, thereby reducing the sidewall of the first connection layer 190 and the second sub-electrode layer. Current density at the intersection of the sidewalls of 112. The current density at the connection between the second sub-electrode layer 112 and the first connection layer 190 is reduced, which can reduce the heat generation, thereby prolonging the service life of the first magnetic field enhancement component 11 .

Please also refer to FIG. 42 , in one embodiment, the first electrode layer 110 further includes a second connection layer 191 . The width of the second connection layer 191 is smaller than the width of the first sub-electrode layer 111 . The second connection layer 191 is disposed on the first surface 101 . The second connection layer 191 and the first connection layer 190 are arranged in parallel and spaced apart, and the first connection layer 190 and the second connection layer 191 are connected in parallel to the first sub-electrode layer 111 and the first sub-electrode layer 111 . between the two sub-electrode layers 112 . The first connection layer 190 and the second connection layer 191 are connected in parallel, which can reduce the current density flowing on the first connection layer 190 and the second connection layer 191 and reduce the heat generation. The first magnetic field enhancement component 11 adopts a plurality of connection layers, which can improve the uniformity of the magnetic field distribution in the width direction of the connection layer, so that the first magnetic field enhancement component 11 can respond to the feedback signal in the width direction of the connection layer. The enhancement effect of the magnetic field is more consistent and the signal quality is improved.

In one embodiment, the included angle between the extension direction of the first connection layer 190 and the extension direction of the second connection layer 191 is an acute angle or an obtuse angle. When a plurality of the first magnetic field enhancement components 11 are distributed in a circular array on the cylindrical support structure 50 , the first connection layer 190 and the first connection layer 190 in the opposite two first magnetic field enhancement components 11 The two connection layers 191 are arranged in a staggered manner, and the overlapping portion in parallel is reduced. The stray capacitance formed between the first connection layer 190 and the air in the opposite two first magnetic field enhancement components 11 is reduced, the stray capacitance formed by the second connection layer 191 and the air is reduced, and the coupling effect is reduced. decrease, the signal quality improves.

In one embodiment, the extending direction of the first connection layer 190 and the second connection layer 191 are arranged asymmetrically. It can be understood that the angle between the extension direction of the first connection layer 190 and the second direction b is not equal to the angle between the extension direction of the first connection layer 190 and the second direction b. When a plurality of the first magnetic field enhancement components 11 are arranged in parallel into a cylindrical structure, the first connection layer 190 in the first magnetic field enhancement component 11 and all the other first magnetic field enhancement components 11 The second connection layers 191 are arranged in a staggered manner, and the overlapping portion in parallel is reduced. The stray capacitance formed by the first connection layer 190 in the first magnetic field enhancement component 11 , the second connection layer 191 in the other first magnetic field enhancement components 11 and air is reduced, and the coupling effect is further decrease, the signal quality is further improved.

Please also refer to FIG. 43 , in one embodiment, the first electrode layer 110 further includes a second connection layer 191 . The second connection layer 191 is disposed on the first surface 101 . The width of the second connection layer 191 is smaller than the width of the first sub-electrode layer 111 . The first sub-electrode layer 111 , the first connection layer 190 , the second connection layer 191 and the second sub-electrode layer 112 are sequentially arranged along the extending direction of the first dielectric layer 100 . The first connection layer 190 is spaced apart from the second connection layer 191 . The first connection layer 190 is connected to the first sub-electrode layer 111 . The second connection layer 191 is connected to the second sub-electrode layer 112 . The first magnetic field enhancement component 11 further includes a first resonance circuit 410 . One end of the first resonance circuit 410 is connected to the first connection layer 190 . The other end of the first resonance circuit 410 is connected to the second connection layer 191 . The first resonant circuit 410 can adjust the capacitance or resistance of the first magnetic field enhancement component 11 .

In one embodiment, the length and width of the first connection layer 190 and the second connection layer 191 are the same, which improves the symmetry of the structure of the first magnetic field enhancement component 11, thereby improving the first magnetic field enhancement The enhancement effect of the component 11 on the magnetic field of the feedback signal is consistent, and the quality of the collected feedback signal (detection signal) is improved.

In one embodiment, the first resonant circuit 410 may include a capacitor, one end of the capacitor is connected to the first connection layer 190 , and the other end of the capacitor is connected to the second connection layer 191 . By adding capacitors to the first resonant circuit 410 , the voltage division between the fourth structural capacitor 306 and the fifth structural capacitor 303 can be reduced, which can prevent capacitor breakdown caused by excessive current generated by electromagnetic induction.

Referring to FIGS. 44 and 45 , the first magnetic field enhancement element 812 includes a second dielectric layer 831 , a sixth electrode layer 832 , a seventh electrode layer 833 , a first depletion MOS transistor 231 and a second depletion MOS Tube 232. The second dielectric layer 831 has a third surface 805 . The second dielectric layer 831 has a fifth end 881 and a sixth end 882 disposed opposite to each other. The sixth electrode layer 832 is disposed on the third surface 805 . The sixth electrode layer 832 is disposed close to the sixth end 882 . The seventh electrode layer 833 is disposed on the third surface 805 . The seventh electrode layer 833 is spaced apart from the sixth electrode layer 832 . The seventh electrode layer 833 is disposed close to the fifth end 881 . The source of the first depletion MOS transistor 231 is connected to the seventh electrode layer 833 . The gate and drain of the first depletion MOS transistor 231 are connected. The gate and drain of the second depletion MOS transistor 232 are connected. The gate and drain of the second depletion MOS transistor 232 are connected to the gate and drain of the first depletion MOS transistor 231 . The source of the second depletion MOS transistor 232 is connected to the sixth electrode layer 832 .

The first depletion-mode MOS transistor 231 and the second depletion-mode MOS transistor 232 have the characteristics of low-voltage on and high-voltage off. In addition, the pinch-off voltage of the first depletion-mode MOS transistor 231 and the second depletion-mode MOS transistor 232 at room temperature is about 1V, and the turn-off time and the recovery time are both on the order of nanoseconds.

In the magnetic resonance system, there is a difference in time sequence between the radio frequency transmitting stage and the radio frequency receiving stage of several tens of milliseconds to several thousand milliseconds, which can quickly realize the first depletion mode MOS transistor 231 and the second depletion mode MOS transistor 232. turn-on and turn-off. The RF power in the RF transmitting stage and the RF receiving stage differs by 3 orders of magnitude. The induced voltage in the coil of the RF transmission stage is between several V and several hundreds of V, and the specific value is related to the selected sequence and flip angle.

The first depletion-mode MOS transistor 231 and the second depletion-mode MOS transistor 232 are connected in series in reverse, so that the sixth electrode layer 832 and the seventh electrode layer 833 can be controlled to be disconnected during the radio frequency emission stage. And it is connected in the RF reception stage. In the radio frequency transmission stage, the first depletion MOS transistor 231 and the second depletion MOS transistor 232 are connected in series in reverse, which can be adapted to the AC environment in the MRI equipment. No matter what the change is, it can ensure that one of the first depletion MOS transistor 231 and the second depletion MOS transistor 232 is turned off, so that the seventh electrode layer 833 and the sixth electrode layer 832 are turned off. Disconnected, not connected.

In the RF transmission stage, the induced voltage is relatively large, the first depletion MOS transistor 231 and the second depletion MOS transistor 232 are in a disconnected state, and the plurality of first magnetic field enhancement components 812 form the The first cylindrical magnetic field enhancer 810 is in an off state, showing a detuned state. There is no current in the first magnetic field enhancement component 812, and no induced magnetic field that would interfere with the radio frequency is generated, which eliminates the influence of the first cylindrical magnetic field enhancer 810 on the magnetic field in the radio frequency transmission stage.

In the RF receiving stage, the first depletion MOS transistor 231 and the second depletion MOS transistor 232 are turned on, thereby ensuring that the sixth electrode layer 832 is connected to the seventh electrode layer 833 . The first cylindrical magnetic field intensifier 810 formed by a plurality of the first magnetic field intensifier components 812 is in a connected state and can exhibit a resonance state, greatly enhance the signal field, and enhance the image signal-to-noise ratio. Therefore, through the first depletion MOS transistor 231 and the second depletion MOS transistor 232, the sixth electrode layer 832 and the seventh electrode layer 833 are controlled to be disconnected during the radio frequency transmission stage, and the radio frequency reception staged connection, so that the first magnetic field enhancement component 812 can only enhance the radio frequency receiving field, but does not enhance the radio frequency transmitting field, thereby improving the image signal-to-noise ratio.

The first magnetic field enhancement component 812 introduces a nonlinear control structure through the first depletion mode MOS transistor 231 and the second depletion mode MOS transistor 232, so that a plurality of the first magnetic field enhancement components 812 form a non-linear control structure. The first cylindrical magnetic field enhancer 810 also has nonlinear response characteristics, and can be applied to all clinical sequences including fast spin echo sequences.

In one embodiment, the second dielectric layer 831 further includes a fourth surface 806 . The fourth surface 806 is disposed opposite to the third surface 805 . The first magnetic field enhancement component 812 further includes a ninth electrode layer 834 and the tenth electrode layer 835 . The ninth electrode layer 834 is disposed on the fourth surface 806 . The ninth electrode layer 834 covers a portion of the fourth surface 806 . The ninth electrode layer 834 is disposed close to the sixth end 882 . The tenth electrode layer 835 is disposed on the fourth surface 806 . The tenth electrode layer 835 covers part of the fourth surface 806 . The tenth electrode layer 835 is disposed close to the fifth end 881 .

The orthographic projection of the ninth electrode layer 834 on the second dielectric layer 831 overlaps with the orthographic projection of the sixth electrode layer 832 on the second dielectric layer 831 to form a seventh structural capacitor 808 . In the resuming part, the sixth electrode layer 832, the second dielectric layer 831 and the ninth electrode layer 834 form the seventh structure capacitor 808. The orthographic projection of the tenth electrode layer 835 on the second dielectric layer 831 overlaps with the orthographic projection of the seventh electrode layer 833 on the second dielectric layer 831 to form a sixth structural capacitor 807 . In the resuming part, the seventh electrode layer 833 , the second dielectric layer 831 and the tenth electrode layer 835 form the sixth structure capacitor 807 .

The seventh electrode layer 833 between the sixth structure capacitor 807 and the first depletion MOS transistor 231 may form a first transmission line. The sixth electrode layer 832 between the second depletion MOS transistor 232 and the seventh structure capacitor 808 may form a second transmission line. The sixth structure capacitor 807 , the first depletion MOS transistor 231 , the second depletion MOS transistor 232 and the seventh structure capacitor 808 are connected in series through the first transmission line and the second transmission line. Therefore, by connecting the sixth structure capacitor 807 , the first depletion MOS transistor 231 , the second depletion MOS transistor 232 and the seventh structure capacitor 808 in series, multiple The resonant frequency of the first cylindrical magnetic field intensifier 810 formed by a magnetic field intensifier assembly 812 is adjusted, which shortens the adjustment time of the first cylindrical magnetic field intensifier 810 after being placed in the MRI system.

The first magnetic field enhancement component 812 will generate an induced voltage in a magnetic field environment. Parasitic capacitance may be formed in the transmission line portion formed by the sixth electrode layer 832 and the seventh electrode layer 833 . The parasitic capacitance is in a parallel relationship with the seventh structure capacitance 808 and the sixth structure capacitance 807 . In the radio frequency receiving stage, the sixth structure capacitor 807 and the seventh structure capacitor 808 form a structure in which capacitors are connected in series, and the induced voltage is divided into multiple pieces, thereby reducing the sixth structure capacitor 807 and the seventh structure capacitor The voltage divider of capacitor 808.

Further, the sixth structure capacitor 807 and the seventh structure capacitor 808 form a capacitor series structure, which can reduce the voltage on the parasitic capacitor. The voltage on the parasitic capacitance is reduced, reducing the harm of the parasitic capacitance, thereby reducing the load effect. The load effect of the first magnetic field enhancement components 812 is reduced, so that the resonant frequency of the first cylindrical magnetic field intensifier 810 formed by the plurality of the first magnetic field enhancement components 812 is not easily affected by the object to be measured, thereby increasing the The enhanced performance of the first cylindrical magnetic field enhancer 810 is enhanced, and the stability of the resonance frequency is enhanced.

The embodiments of the present application further provide a magnetic resonance system. The magnetic resonance system includes the magnetic field enhancement device 20 .

Referring to FIGS. 46 and 47 , an embodiment of the present application provides a curved magnetic field enhancement device 30 , including a flexible support body 500 , a plurality of magnetic field enhancement components, a first conductive sheet 510 and a second conductive sheet 520 . The flexible support body 500 can be bent into a curved surface. The plurality of magnetic field enhancement components are disposed on the flexible support body 500 in parallel and spaced apart. Each of the magnetic field enhancement components includes a first electrical connection end 911 and a second electrical connection end 912 . A structure capacitor and an inductance structure connected in series are connected between the first electrical connection terminal 911 and the second electrical connection terminal 912 . The first conductive sheets 510 are respectively connected to the first electrical connection ends 911 of the plurality of magnetic field enhancement components. The second conductive sheets 520 are respectively connected to the second electrical connection ends 912 of the plurality of magnetic field enhancement components. The resonant frequency of the curved magnetic field enhancement device 30 is equal to the target frequency.

Under the action of external force, the flexible support body 500 can be bent. The flexible support body 500 can be bent into a curved surface, and can be a flat surface. The arc size of the detection curved surface formed by the flexible support body 500 can be adjusted. When the thickness of the patient's abdomen is different, by changing the curvature of the flexible support body 500, the plurality of magnetic field enhancement components can be fitted to the detection part of the human body, and the detection part and the curved magnetic field enhancement device 30 can be reduced. gap, the strength of the detection signal increases, and the signal quality improves.

Referring to FIG. 48 , during the application process of the curved magnetic field enhancement device 30 provided by the embodiment of the present application, the curved magnetic field enhancement device 30 is disposed at the detection site. The resonant frequency of the curved magnetic field enhancement device 30 is equal to the target frequency. The curved magnetic field enhancement device 30 resonates with the detection part, the magnetic field strength of the detection signal is increased, and the quality of the signal collected by the radio frequency coil is improved. In addition, both of the curved magnetic field enhancement devices 30 can enhance the feedback signal magnetic field of the detection site. Since the detection part is between the two curved magnetic field enhancement devices 30 , the plurality of magnetic field enhancement components in the curved magnetic field enhancement device 30 are arranged at intervals in the same curved surface. The curved magnetic field enhancement device 30 is a special-shaped curved MRI image enhancement metasurface device. The special-shaped curved MRI image enhancement metasurface device is a curved structure, which can fit with the abdomen of the human body. The special-shaped curved MRI image enhancement metasurface device can cover the abdomen of the human body, reducing the gap between the special-shaped curved MRI image enhancing metasurface device and the abdomen, and improving the signal quality for detecting the human abdomen. FIG. 3 is a magnetic field distribution diagram of the curved magnetic field enhancement device 30 . The magnetic field distribution of the area surrounded by the curved magnetic field enhancement device 30 is uniform.

In one embodiment, the capacitance values of the magnetic field enhancement components in the curved magnetic field enhancement device 30 are all the same, and the inductance values are the same.

In one embodiment, the inductance value of the inductance structure in the magnetic field enhancement component at the edge of the curved magnetic field enhancement device 30 is greater than the inductance value of the inductance structure in the magnetic field enhancement component in the middle of the curved magnetic field enhancement device 30. The capacitance value of the capacitance structure in the magnetic field enhancement component at the edge of the curved magnetic field enhancement device 30 is smaller than the capacitance value of the capacitance structure in the magnetic field enhancement component in the middle of the curved magnetic field enhancement device 30 .

When the curved magnetic field enhancement device 30 works in resonance, the magnetic field is mainly distributed around the inductance structure of the magnetic field enhancement component. In the middle of the curved magnetic field enhancement device 30, there are magnetic field enhancement elements on both sides of each of the magnetic field enhancement elements. The magnetic fields in each of the magnetic field enhancement elements and two adjacent magnetic field enhancement elements are superimposed on each other. , the magnetic field is greatly enhanced. Only one side of the magnetic field enhancement component at the edge of the curved magnetic field enhancement device 30 has the magnetic field enhancement component. The magnetic field enhancement degree of the magnetic field enhancement component at the edge of the curved magnetic field enhancement device 30 is relatively small. By reducing the capacitance value of the capacitance structure in the magnetic field enhancement component at the edge of the curved magnetic field enhancement device 30 , the partial pressure in the capacitance structure of the magnetic field enhancement component can be reduced. When the total resonant frequency remains unchanged, the partial pressure of the inductance increases, enhancing the magnetic field strength near the capacitance structure of the magnetic field enhancement component, thereby improving the uniformity of the magnetic field distribution of the feedback signal and improving the stability of the detection signal.

In one embodiment, the magnetic field enhancement component is the second magnetic field enhancement component 12 . The second magnetic field enhancement component 12 includes the first dielectric layer 100 , the first electrode layer 110 , the second electrode layer 120 and the third electrode layer 130 . The structures, materials, and implementations of the first dielectric layer 100 , the first electrode layer 110 , the second electrode layer 120 and the third electrode layer 130 may be the same as or similar to the above-mentioned embodiments, and will not be repeated here. Repeat.

Optionally, the first electrical connection terminal 911 is the second structural capacitor 152 . The second electrical connection terminal 912 is the third structure capacitor 153 . The first conductive sheets 510 are respectively connected to the second electrode layers 120 of the plurality of second magnetic field enhancement components 12 . The second conductive sheets 520 are respectively connected to the third electrode layers 130 of the plurality of second magnetic field enhancement components 12 .

Please also refer to FIG. 49 , in one embodiment, the curved magnetic field enhancement device 30 further includes an output matching circuit 640 . The output matching circuit 640 is connected to the first electrical connection terminal 911 . The output matching circuit 640 is also used for connecting with a signal acquisition device. The output matching circuit 640 is the same as adjusting the impedance value and the resonant frequency of the signal acquisition device.

The curved magnetic field enhancement device 30 can adjust the impedance value at both ends of the signal acquisition device through the output matching circuit 640, so that the output impedance of the output matching circuit 640 matches the output impedance of the cable to reduce reflection. The second magnetic field enhancement component 12 can also adjust the resonance frequency through the output matching circuit 640, so that the resonance frequency of the output matching circuit 640 and the signal acquisition device on the output side is equal to the target frequency, and the output detection signal is improved. strength. In the radio frequency receiving stage, the curved magnetic field enhancement device 30 resonates, and the magnetic field of the curved magnetic field enhancement device 30 has the same characteristics as the magnetic field generated by the feedback signal of the human body. The second magnetic field enhancement component 12 can match the output impedance and increase the signal strength through the output matching circuit 640, and can take out the detection signal. Further, the curved magnetic field enhancement device 30 can be closer to the object under test, the detection sensitivity of the curved magnetic field enhancement device 30 is higher, and the detected image is clearer.

In one embodiment, the output matching circuit 640 is connected to two electrodes of the second structure capacitor 152 respectively.

In one embodiment, the output matching circuit 640 includes a matching capacitor 641 and a tuning capacitor 642 . One end of the matching capacitor 641 is connected to the positive electrode of the first electrical connection terminal 911 . The tuning capacitor 642 is connected between the other end of the matching capacitor 641 and the negative electrode of the first electrical connection terminal 911 . That is, one end of the matching capacitor 641 is connected to the first sub-electrode layer 111 . The tuning capacitor 642 is connected between the other end of the matching capacitor 641 and the second electrode layer 120 . Both ends of the tuning capacitor 642 are used to connect with the signal acquisition device.

The tuning capacitor 642 is connected in parallel with the signal acquisition device, and the tuning capacitor 642 is mainly used to adjust the resonant frequency of the signal output circuit, so that the resonant frequency of the output side where the signal acquisition device is located is equal to the target resonant frequency. In the radio frequency receiving stage, the output matching circuit 640 on the output side resonates with the signal acquisition device, and the strength of the detection signal is enhanced, which facilitates the output of the detection signal.

The matching capacitor 641 is connected in series with the tuning capacitor 642 and is connected in series with the signal acquisition device. The matching capacitor 641 can adjust the impedance of the output matching circuit 640 on the output side by adjusting its own capacitive reactance, so that the output impedance of the system is matched with the output impedance of the cable to reduce reflection. The output impedance of a typical coaxial line is 50 ohms or 75 ohms. In order to make the output impedance of the output matching circuit 640 match the output impedance of the cable to reduce reflection. A typical coaxial line has an output impedance of 50 ohms or 75 ohms. The matching capacitor 641 and the tuning capacitor 642 may be adjustable capacitors.

Please refer to FIG. 50 together. In one embodiment, the first switching element 651 includes a first depletion MOS transistor 652 and a second depletion MOS transistor 653 connected in reverse series. The first depletion MOS transistor 652 and the second depletion MOS transistor 653 are connected in series between the output matching circuit 640 and the first sub-electrode layer 111 . The gate and drain of the first depletion MOS transistor 652 are connected to the end of the matching capacitor 641 away from the tuning capacitor 642. The source of the first depletion MOS transistor 652 is connected to the source of the second depletion MOS transistor 653 . The gate and drain of the second depletion MOS transistor 653 are connected to the first sub-electrode layer 111 .

The first depletion MOS transistor 652 and the second depletion MOS transistor 653 are used for alternately conducting in the radio frequency receiving stage. The first depletion MOS transistor 652 and the second depletion MOS transistor 653 are also used for disconnection during the radio frequency transmission stage.

The curved magnetic field enhancement device 30 is applied to the MRI system to enhance the magnetic field strength of the feedback signal of the human body in the radio frequency receiving stage. The magnetic field in the radio frequency transmission stage of the MRI system is mainly the radio frequency magnetic field emitted by the radio frequency device. The magnetic field in the receiving stage is mainly the magnetic field generated by the feedback signal of the human body. The magnetic field energy in the transmitting stage is more than 1000 times the magnetic field energy in the receiving stage. The induced voltage of the second magnetic field enhancement component 12 in the emission stage is between several tens of volts to several hundreds of volts. The induced voltage of the second magnetic field enhancing component 12 in the receiving stage is less than 1 volt.

In the radio frequency transmission stage, the voltage across the first depletion MOS transistor 652 and the second depletion MOS transistor 653 is greater than the pinch-off voltage, and the first depletion MOS transistor 652 and the second depletion MOS transistor 652 Although the MOS transistor 653 is not turned on, no current flows in the output matching circuit 640 . The purpose of connecting the first depletion MOS transistor 652 and the second depletion MOS transistor 653 in reverse series is to respond to the AC voltage.

In the radio frequency receiving stage, the source and drain of the first depletion MOS transistor 652 or the second depletion MOS transistor 653 are turned on. The matching capacitor 641 is connected to the first sub-electrode layer 111 . The output matching circuit 640 resonates, and the detection signal can be output to the signal acquisition device.

In one embodiment, the output matching circuit 640 is connected to the second magnetic field enhancement component 12 in the middle of the curved magnetic field enhancement device 30 . The second magnetic field enhancement components 12 on both sides of the second magnetic field enhancement component 12 in the middle are symmetrically distributed, the magnetic field of the second magnetic field enhancement component 12 in the middle is uniformly affected by both sides, and the detection signal stability is good , the signal quality is better. Therefore, the output matching circuit 640 is disposed in the middle of the second magnetic field enhancement component 12, and the quality of the output signal is better.

Please also refer to FIG. 51 , in one embodiment, the curved magnetic field enhancement device 30 further includes a first tuning circuit 60 . The first tuning circuit 60 is connected to the first electrical connection terminal 911 . The first tuning circuit 60 is used to make the curved magnetic field enhancement device 30 resonate when it is in the radio frequency receiving stage. The first tuning circuit 60 is used for detuning the curved magnetic field enhancement device 30 when it is in the radio frequency transmitting stage.

In one embodiment, the first tuning circuit 60 includes a switch control circuit 420 . One end of the switch control circuit 420 is connected to the first sub-electrode layer 111 , and the other end of the switch control circuit 420 is connected to the second electrode layer 120 . The switch control circuit 420 is configured to be turned on in the RF transmitting stage and turned off in the RF receiving stage.

The switch control circuit 420 is connected in parallel with the second structure capacitor 152 . Therefore, in the radio frequency transmission stage, the switch control circuit 420 is turned on, and the first sub-electrode layer 111 and the second electrode layer 120 are electrically connected. In the radio frequency receiving stage, the switch control circuit 420 is turned off, and the first sub-electrode layer 111 and the second electrode layer 120 are disconnected. The turn-on voltage of the switch control circuit 420 may be greater than 1 volt. That is, when the voltage difference between the two ends of the first sub-electrode layer 111 and the second electrode layer is greater than 1 volt, the switch control circuit 420 is turned on. When the voltage difference between the first sub-electrode layer 111 and the second electrode layer 120 is less than 1 volt, the switch control circuit 420 is turned off.

In the radio frequency transmitting stage, the switch control circuit 420 is turned on due to the large voltage difference across the structural capacitor. The first sub-electrode layer 111 and the second electrode layer 120 are electrically connected. At this time, the first sub-electrode layer 111 and the second electrode layer 120 cannot form the second structural capacitor 152 . That is, the curved magnetic field enhancement device 30 does not have resonance performance. Therefore, the curved magnetic field enhancement device 30 cannot enhance the RF transmission field.

In the radio frequency receiving stage, the voltage difference between the first sub-electrode layer 111 and the second electrode layer 120 is small, the switch control circuit 420 is turned off, and the first sub-electrode layer 111 and the second electrode layer 120 are turned off. The two electrode layers 120 are disconnected. At this time, the first sub-electrode layer 111 and the second electrode layer 120 constitute the second structural capacitor 152 . Therefore, a plurality of the second magnetic field enhancing components 12 form an LC oscillating circuit. The curved magnetic field enhancement device 30 can enhance the radio frequency magnetic field formed by the feedback signal of the detection site.

Please refer to FIG. 52 together. In one embodiment, the first tuning circuit 60 further includes an external capacitor 440 . Two ends of the external capacitor 440 are respectively connected to the first sub-electrode layer 111 and the second electrode layer 120 . The external capacitor 440 may be an adjustable capacitor connected in parallel with the first sub-electrode layer 111 and the second electrode layer 120 . The external capacitor 440 cooperates with the third structural capacitor 153 to adjust the resonance performance of the second magnetic field enhancement component 12 . In the RF receiving stage, the external capacitor 440 is connected in parallel with the third structure capacitor 153 , the external capacitor 440 is set at the first end 103 , and the third structure capacitor 153 is set at the second end 104 , the magnetic field in the extending direction of the second magnetic field enhancement component 12 can be balanced, so that the uniformity of the magnetic field is improved, and the quality of the detection signal is improved.

In one embodiment, the switch control circuit 420 includes a first diode 431 and a second diode 432 . The anode of the first diode 431 is connected to the first sub-electrode layer 111 . The cathode of the first diode 431 is connected to the second electrode layer 120 . The cathode of the second diode 432 is connected to the first sub-electrode layer 111 , and the anode of the second diode 432 is connected to the second electrode layer 120 .

It can be understood that the turn-on voltages of the first diode 431 and the second diode 432 may be 0 volts to 1 volts. In one embodiment, the turn-on voltage of the first diode 431 and the second diode 432 may be 0.8 volts.

In the radio frequency transmission stage, due to the large voltage difference across the structural capacitance, the first diode 431 and the second diode 432 are turned on. The first sub-electrode layer 111 and the second electrode layer 120 are electrically connected. At this time, the first sub-electrode layer 111 and the second electrode layer 120 cannot form the second structural capacitor 152 . That is, the curved magnetic field enhancement device 30 does not have resonance performance. Therefore, the curved magnetic field enhancement device 30 cannot enhance the radio frequency emission field.

In the radio frequency receiving stage, the voltage difference between the first sub-electrode layer 111 and the second electrode layer 120 is small, the first diode 431 and the second diode 432 are not conductive, The first sub-electrode layer 111 and the second electrode layer 120 are disconnected. At this time, the first sub-electrode layer 111 and the second electrode layer 120 constitute the second structural capacitor 152 . Therefore, a plurality of the second magnetic field enhancing components 12 form an LC oscillating circuit. The curved magnetic field enhancement device 30 can enhance the radio frequency magnetic field formed by the feedback signal of the detection site.

Please refer to FIG. 53 together. In one embodiment, the first tuning circuit 60 further includes a third external capacitor 443 . The external capacitor 440 and the third external capacitor 443 are connected in series between the first sub-electrode layer 111 and the second electrode layer 120 , and the switch control circuit 420 is connected in parallel with the external capacitor 440 . both ends. The switch control circuit 420 is configured to be turned on in the RF transmitting stage and turned off in the RF receiving stage.

The external capacitor 440 and the third external capacitor 443 may be adjustable capacitors. In the RF transmission stage, due to the large voltage difference between the first sub-electrode layer 111 and the second electrode layer 120, the The switch control circuit 420 is turned on. The third external capacitor 443 is connected between the first sub-electrode layer 111 and the second electrode layer 120. By adjusting the third external capacitor 443, the loop in which the second magnetic field enhancement component 12 is located can be adjusted The degree of tuning during the RF transmit phase. That is, the tuning degree of the curved magnetic field enhancement device 30 in the radio frequency transmission stage can be adjusted by the third external capacitor 443 .

In the RF transmission stage, by adjusting the third external capacitor 443, the magnetic field of the measured area after adding the curved magnetic field enhancement device 30 can be the same as the magnetic field strength before the curved magnetic field enhancement device 30 is added. At this time, the measured area Maintaining the original magnetic field strength can eliminate the influence of the curved magnetic field enhancement device 30 on the RF transmission stage, so that the curved magnetic field enhancement device 30 can be applied to all clinical sequences, and the clinical utility of the curved magnetic field enhancement device 30 is improved sex.

See also Figure 54, in one embodiment. The first tuning circuit 60 further includes a fifth external capacitor 445 . The fifth external capacitor 445 and the switch control circuit 420 are connected in series between the first sub-electrode layer 111 and the second sub-electrode layer 112 . The circuit formed by the fifth external capacitor 445 and the switch control circuit 420 in series is connected in parallel with the external capacitor 440 .

Therefore, when the switch control circuit 420 is turned on, the fifth external capacitor 445 and the external capacitor 440 are connected in parallel to the first sub-electrode layer 111 and the second sub-electrode layer 112 . Compared with two capacitors connected in series, when the total capacitance value of the second magnetic field enhancement component 12 is equal, the capacitance value of the fifth external capacitor 445 and the external capacitor 440 in parallel is larger, so the required The capacitance values of the second structural capacitor 152 and the third structural capacitor 153 may be relatively small, so the loss of the second magnetic field enhancement component 12 is reduced.

In the radio frequency transmission stage, the resonant frequency of the loop in which the second magnetic field enhancement component 12 is located deviates far from the operating frequency of the magnetic resonance system. Therefore, by adjusting the fifth external capacitor 445 and the external capacitor 440, it can be ensured that in the magnetic resonance system In the radio frequency transmission stage, the magnetic field strength of the second magnetic field enhancement component 12 is the same. It can be understood that the linear response characteristic of the curved magnetic field enhancement device 30 determines that it has the same resonance performance in the radio frequency transmitting and radio frequency receiving stages.

In the radio frequency emission stage, the voltage difference between the first sub-electrode layer 111 and the second sub-electrode layer 112 is relatively large, and the switch control circuit 420 is turned on. The external capacitor 440 and the fifth external capacitor 445 are connected in series between the first sub-electrode layer 111 and the second sub-electrode layer 112 .

In the radio frequency receiving stage, the voltage difference between the first sub-electrode layer 111 and the second sub-electrode layer 112 is small, and the switch control circuit 420 is turned off. Only the external capacitor 440 is connected in series between the first sub-electrode layer 111 and the second sub-electrode layer 112. By adjusting the external capacitor 440, the resonant frequency of the loop where the second magnetic field enhancement component 12 is located can be adjusted so that the resonant frequency is equal to the frequency of the radio frequency coil, thereby greatly enhancing the radio frequency receiving field and improving the image signal-to-noise ratio.

The circuit in which the fifth external capacitor 445 and the external capacitor 440 are connected in parallel can be connected through the first connection layer 190 and the second connection layer 191 .

By adjusting the external capacitor 440 and the fifth external capacitor 445 , the loop in which the second magnetic field enhancement component 12 is located can have a good resonance frequency in the radio frequency receiving stage. Finally, the resonant frequency of the loop in which the second magnetic field enhancement component 12 is located in the receiving stage reaches the working frequency of the magnetic resonance system.

Referring to FIG. 55, in one embodiment, the second magnetic field enhancement component 12 includes a first dielectric layer 100, a first electrode layer 110, a second electrode layer 120, a third electrode layer 130, a fourth electrode layer 140 and The second tuning circuit 70 . The first dielectric layer 100 has a first end 103 and a second end 104 which are arranged opposite to each other at a distance. The first dielectric layer 100 includes an opposing first surface 101 and a second surface 102 . The first electrode layer 110 and the second electrode layer 120 are disposed on the first surface 101 at intervals. The first electrode layer 110 is disposed close to the first end 103 . The second electrode layer 120 is disposed close to the second end 104 . The third electrode layer 130 and the fourth electrode layer 140 are disposed on the second surface 102 at intervals. The third electrode layer 130 is disposed close to the first end 103 . The fourth electrode layer 140 is disposed close to the second end 104 . The orthographic projection of the first electrode layer 110 on the first dielectric layer 100 partially overlaps the orthographic projection of the third electrode layer 130 on the first dielectric layer 100 . The first electrode layer 110 , the first dielectric layer 100 and the third electrode layer 130 constitute a second structural capacitor 152 . The orthographic projection of the second electrode layer 120 on the first dielectric layer 100 partially overlaps the orthographic projection of the fourth electrode layer 140 on the first dielectric layer 100 . The second electrode layer 120 , the first dielectric layer 100 and the fourth electrode layer 140 constitute a third structural capacitor 153 .

One end of the second tuning circuit 70 is connected to the first electrode layer 110 . The other end of the second tuning circuit 70 is connected to the second electrode layer 120 . The second tuning circuit 70 is used to make the second magnetic field enhancement component 12 conduct in the radio frequency receiving stage, and the second tuning circuit 70 is in a high impedance state in the radio frequency transmitting stage.

The second tuning circuit 70 in the curved magnetic field enhancement device 30 in the embodiment of the present application is used to make the second magnetic field enhancement component 12 conduct when it is in the radio frequency receiving stage, so as to improve the magnetic field strength of the human body feedback signal . The second tuning circuit 70 is also used to be in a high-impedance state during the RF transmission stage. In the radio frequency receiving stage, the second tuning circuit 70 connects the first electrode layer 110 and the second electrode layer 120 to form an LC oscillation circuit. In the RF transmission stage, the second tuning circuit 70 disconnects the first electrode layer 110 from the second electrode layer 120, so that an LC oscillation circuit cannot be formed, and it does not have the effect of enhancing the magnetic field, thereby reducing the impact on the RF transmission magnetic field. influences.

The second structural capacitor 152 is the first electrical connection terminal 911 . The third structural capacitor 153 is the second electrical connection terminal 912 . The first conductive sheets 510 are respectively connected to the third electrode layers 130 of the plurality of second magnetic field enhancement components 12 . The second conductive sheets 520 are respectively connected to the fourth electrode layers 140 of the plurality of second magnetic field enhancement components 12 .

In one embodiment, the second tuning circuit 70 includes a third depletion MOS transistor 231 and a fourth depletion MOS transistor 232 . The source of the third depletion MOS transistor 231 is electrically connected to the second electrode layer 120 . The gate and drain of the third depletion MOS transistor 231 are electrically connected to the gate and drain of the fourth depletion MOS transistor 232 . The source of the fourth depletion MOS transistor 232 is electrically connected to the first electrode layer 110 .

The third depletion MOS transistor 231 is connected in series with the fourth depletion MOS transistor 232 . In the radio frequency transmission stage, the radio frequency coil transmits the radio frequency transmission signal, and the field strength of the magnetic field is relatively large. The induced voltage generated by the loop where the second magnetic field enhancement component 12 is located is relatively large. The voltage between the third depletion MOS transistor 231 and the fourth depletion MOS transistor 232 exceeds the pinch-off between the third depletion MOS transistor 231 and the fourth depletion MOS transistor 232 voltage, the source and drain of the third depletion MOS transistor 231 are non-conductive, and the source and drain of the fourth depletion MOS transistor 232 are non-conductive. There is almost no current flow between the second structural capacitor 152 and the third structural capacitor 153, and the magnetic field generated by the loop in which the second magnetic field enhancement component 12 is located is weakened, thereby reducing the pair of the second magnetic field enhancement component 12. The influence of the magnetic field in the radio frequency emission stage can reduce the artifacts of the detected image and improve the clarity of the detected image.

In the RF receiving stage, the detection part transmits a feedback signal, and the field strength of the magnetic field is small. The induced voltage generated by the second magnetic field enhancement component 12 is relatively small. The voltage between the third depletion MOS transistor 231 and the fourth depletion MOS transistor 232 is smaller than the pinch-off of the third depletion MOS transistor 231 and the fourth depletion MOS transistor 232 voltage, the source and drain of the third depletion MOS transistor 231 are turned on, and the source and drain of the fourth depletion MOS transistor 232 are turned on. The second structural capacitor 152 and the third structural capacitor 153 are connected to form an LC circuit, which can enhance the magnetic field.

Please refer to FIG. 56 together. In one embodiment, the second tuning circuit 70 includes a first capacitor 223 , a first inductor 241 and a first switch circuit 631 . One end of the first capacitor 223 is connected to the first electrode layer 110 . The other end of the first capacitor 223 is connected to the third electrode layer 130 . One end of the first inductor 241 is connected to the third electrode layer 130 . The first switch circuit 631 is connected between the other end of the first inductor 241 and the first electrode layer 110 . The first switch circuit 631 is configured to be turned off during the radio frequency receiving stage. The first switch circuit 631 is also configured to be turned on during the RF transmission stage, so that the control circuit 630 is in a high-impedance state.

The first switch circuit 631 in the second magnetic field enhancement component 12 is configured to be turned off during the radio frequency receiving stage. The second structure capacitor 152 and the third structure capacitor 153 are connected through the first capacitor 223 . The first switch circuit 631 and the first inductor 241 do not participate in circuit conduction. The first switch circuit 631 is also configured to be turned on during the radio frequency transmission stage, and the first capacitor 223 is connected in parallel with the first inductor 241, so that the second tuning circuit 70 is in a high-impedance state. The circuit between the second structure capacitor 152 and the third structure capacitor 153 is disconnected. During the RF signal transmission stage, there is almost no current flow between the second structural capacitor 152 and the third structural capacitor 153, and the magnetic field generated by the second magnetic field enhancement component 12 is weakened, thereby reducing the second magnetic field enhancement The influence of the component 12 on the magnetic field in the transmitting stage of the radio frequency signal can reduce the artifacts of the detected image and improve the definition of the detected image.

The first switch circuit 631 may be controlled by a control circuit. In one embodiment, the first switch circuit 631 includes a switch element and a control terminal. One end of the switching element is connected to the end of the first inductor 241 away from the third electrode layer 130 . The other end of the switching element is connected to the first electrode layer 110 . The control terminal is connected with an external control device. The control terminal is used for receiving closing and opening commands. In the radio frequency transmission stage, the control device outputs a closing command to the control terminal. When the control terminal receives a closing command, the first inductor 241 is connected to the first electrode layer 110 . The first inductor 241 is connected in parallel with the first capacitor 223 to generate parallel resonance and is in a high resistance state; there is almost no current flow between the first electrode layer 110 and the third electrode layer 130 .

In the radio frequency receiving stage, the control device outputs a closing command to the control terminal. When the control terminal receives a disconnection command, the first inductor 241 is disconnected from the first electrode layer 110 . The first electrode layer 110 , the first capacitor 223 and the third electrode layer 130 are connected in series to form a part of a resonant circuit.

In one embodiment, the first switch circuit 631 includes a third diode 451 and a fourth diode 452 . The anode of the third diode 451 is connected to the first electrode layer 110 . The cathode of the third diode 451 is connected to the other end of the first inductor 241 . The anode of the fourth diode 452 is connected to the other end of the first inductor 241 , and the cathode of the fourth diode 452 is connected to the first electrode layer 110 .

The third diode 451 and the fourth diode 452 are connected in antiparallel. In the radio frequency transmission stage, the radio frequency coil transmits the radio frequency transmission signal, and the field strength of the magnetic field is relatively large. The induced voltage generated by the second magnetic field enhancement component 12 is relatively large. The positive and negative voltages applied across the third diode 451 and the fourth diode 452 alternate. When the loaded voltage exceeds the turn-on voltage of the third diode 451 and the fourth diode 452, the third diode 451 and the fourth diode 452 are turned on. The first capacitor 223 is connected in parallel with the first inductor 241, so that the control circuit 630 is in a high resistance state. In the radio frequency signal transmission stage, there is almost no current flow between the second structure capacitor 152 and the third structure capacitor 153, and the magnetic field generated by the loop where the second magnetic field enhancement component 12 is located is weakened, thereby reducing the second magnetic field The influence of the circuit in which the component 12 is located on the magnetic field in the radio frequency signal transmission stage is enhanced, thereby reducing the artifacts of the detected image and improving the clarity of the detected image.

In the RF receiving stage, the detection part transmits a feedback signal, and the field strength of the magnetic field is small. The induced voltage generated by the second magnetic field enhancement component 12 is relatively small. The loaded voltage cannot reach the turn-on voltages of the third diode 451 and the fourth diode 452, and the third diode 451 and the fourth diode 452 are non-conductive. The second structural capacitor 152 and the third structural capacitor 153 are connected through the first capacitor 223, and the curved magnetic field enhancement device 30 composed of a plurality of the second magnetic field enhancement components 12 is in a resonant state to enhance the magnetic field. effect.

In one embodiment, the turn-on voltages of the third diode 451 and the fourth diode 452 are both between 0 and 1V. In one embodiment, the turn-on voltages of the third diode 451 and the fourth diode 452 are the same, so that the magnetic field strength of the curved magnetic field enhancement device 30 continuously increases in the RF receiving stage, thereby increasing the feedback signal stability. In one embodiment, the turn-on voltage of the third diode 451 and the fourth diode 452 is 0.8V.

In one embodiment, the third diode 451 and the fourth diode 452 are of the same model, and the voltage drop after the third diode 451 and the fourth diode 452 are turned on The same, so that the magnetic field strength of the curved magnetic field enhancement device 30 increases by the same magnitude in the radio frequency receiving stage, which further improves the stability of the feedback signal.

Please refer to FIG. 57 together. In one embodiment, the output matching circuit 640 is connected to the two electrodes of the first structure capacitor 150 respectively. That is, one end of the output matching circuit 640 is connected to a part of the electrodes of the first electrode layer 110 that form the first structure capacitor 150 , and the output matching circuit 640 and the second electrode layer 120 form the first structure Part of the electrodes of the capacitor 150 are connected. The output matching circuit 640 is used to adjust the impedance value and the resonant frequency of the signal acquisition device.

The curved magnetic field enhancement device 30 can adjust the matching impedance at both ends of the signal acquisition device through the output matching circuit 640 . The curved magnetic field enhancement device 30 can also adjust the resonance frequency through the output matching circuit 640, so that the resonance frequency of the output matching circuit 640 and the signal acquisition device on the output side is equal to the target frequency, so as to improve the output detection signal strength . In the radio frequency receiving stage, the curved magnetic field enhancement device 30 resonates, and the magnetic field of the curved magnetic field enhancement device 30 has the same characteristics as the magnetic field generated by the feedback signal of the human body. The second magnetic field enhancement component 12 can match the output impedance and increase the signal strength through the output matching circuit 640, and can take out the detection signal. Further, the curved magnetic field enhancement device 30 is closer to the object under test, the detection sensitivity of the curved magnetic field enhancement device 30 is higher, and the detected image is clearer.

Please refer to FIG. 58 together. In one embodiment, the first tuning circuit 60 is connected to two electrodes of the first structural capacitor 150 . That is, one end of the first tuning circuit 60 is connected to the first electrode layer 110 to form part of the electrodes of the first structural capacitor 150 , and the other end of the first tuning circuit 60 is connected to the second electrode layer 120 . Part of the electrodes of the first structural capacitor 150 are connected. The first tuning circuit 60 is used to resonate the curved magnetic field enhancement device 30 where the second magnetic field enhancement component 12 is located in the radio frequency receiving stage. The first tuning circuit 60 is used to tune the curved magnetic field enhancement device 30 where the second magnetic field enhancement component 12 is located during the radio frequency transmission stage.

Please also refer to FIG. 59 , in one embodiment, some electrodes of the first electrode layer 110 that do not form the first structure capacitor 150 function as connecting lines. The first electrode layer 110 does not constitute part of the electrode opening ports of the first structural capacitor 150, and the two ends of the second tuning circuit 70 are connected to the two ends of the ports one by one. The second tuning circuit 70 is used to make the second magnetic field enhancement component 12 conduct when in the radio frequency receiving stage, so as to improve the magnetic field strength of the feedback signal of the human body. The second tuning circuit 70 is also used to be in a high-impedance state during the RF transmission stage. In the radio frequency receiving stage, the second tuning circuit 70 connects both ends of the first electrode layer 110 to form an LC oscillation circuit. In the radio frequency transmission stage, the second tuning circuit 70 disconnects both ends of the first electrode layer 110, so that the LC oscillation circuit cannot be formed, and it does not have the effect of enhancing the magnetic field, thereby reducing the influence on the radio frequency transmission magnetic field.

In one embodiment, the surface of the flexible support body 500 is provided with a plurality of fixing structures 930 . The plurality of fixing structures 930 are arranged in an array. A plurality of the fixing structures 930 are used for fixing the second magnetic field enhancing components 12 one by one. The plurality of fixing structures 930 are arranged in an array on the same surface of the flexible support body 500 . The second magnetic field enhancement assembly 12 can be fixed to the flexible support body 500 by the fixing structure 930 .

The fixing structure 930 may be a strap or a buckle or the like. The second magnetic field enhancement component 12 is detachably fixed to the flexible support body 500 through the fixing structure 930 .

In one embodiment, the fixing structure 930 includes a first fixing member 931 and a second fixing member 932 arranged at intervals. The first fixing member 931 is used for fixing one end of the second magnetic field enhancing component 12 . The second fixing member 932 is used for fixing the other end of the second magnetic field enhancing component 12 . The first fixing member 931 and the second fixing member 932 are respectively used for fixing two ends of the second magnetic field enhancing assembly 12 .

In one embodiment, the first fixing member 931 includes a U-shaped buckle. Both ends of the U-shaped clip include mounting plates. The mounting plate has a through hole. Corresponding positions of the flexible support body 500 are provided with threaded holes. When the second magnetic field enhancement assembly 12 needs to be installed on the flexible support body 500, it is only necessary to place the second magnetic field enhancement assembly 12 on the surface of the flexible support body 500, and then press the U-shaped clip on the flexible support body 500. The second magnetic field enhancement assembly 12 is passed through the through hole of the U-shaped buckle with a bolt and screwed into the threaded hole of the flexible support body 500 . When the second magnetic field enhancement assembly 12 needs to be detached from the flexible support body 500, only the bolts need to be unscrewed.

The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be regarded as the scope described in this specification.

The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. Inside. The above are only the preferred embodiments of the present application. It should be pointed out that for those skilled in the art, without departing from the technical principles of the present application, several improvements and modifications can also be made, and these improvements and modifications should also be It is regarded as the protection scope of this application.

Claims

A magnetic field enhancement device, comprising:

A cylindrical support structure (50), having two spaced opposite third ends (51) and fourth ends (53); a plurality of magnetic field enhancement components, arranged at intervals on the cylindrical support structure (50) and extending along the the third end (51) extends towards the fourth end (53); and

A first annular conductive sheet (510), disposed on the cylindrical support structure (50) and close to the third end (51), the first annular conductive sheet (510) has a first opening (501) , the first opening (501) is at least partially located between two adjacent magnetic field enhancement components, and the first annular conductive sheet (510) and the plurality of magnetic field enhancement components are located at the third end ( 51) part of the electrical connection; and

A second annular conductive sheet (520) is disposed on the cylindrical support structure (50) and is close to the fourth end (53), the second annular conductive sheet (520) has a second opening (502) , the second opening (502) is at least partially located between two adjacent magnetic field enhancement components, and the second annular conductive sheet (520) and the plurality of magnetic field enhancement components are located at the fourth end ( 53) part of the electrical connection.
The magnetic field enhancement device according to claim 1, wherein the first opening (501) and the second opening (502) are located between two adjacent magnetic field enhancement components.
The magnetic field enhancement device according to claim 2, wherein the cylindrical support structure (50) has a central symmetry plane (50) located between the third end (51) and the fourth end (53). 506), the first opening (501) and the second opening (502) are symmetrical with respect to the central symmetry plane (506).
The magnetic field enhancement device according to claim 2, wherein the arc length corresponding to the first opening (501) and the arc length corresponding to the second opening (502) are smaller than two adjacent ones of the magnetic field enhancement devices Arc length between components.
The magnetic field enhancement device according to claim 4, characterized in that, the arc length corresponding to the first opening (501) and the arc length corresponding to the second opening (502) are two adjacent ones of the magnetic field enhancement devices One-third to one-half the arc length between components.
The magnetic field enhancement device of claim 1, wherein the magnetic field enhancement component comprises:

a first dielectric layer (100), comprising a first surface (101) and a second surface (102) disposed oppositely;

A first electrode layer (110) is disposed on the first surface (101), the first electrode layer (110) covers part of the first surface (101), and the first electrode layer (110) is connected to the first surface (101). the first annular conductive sheet (510) is connected;

The second electrode layer (120) is disposed on the second surface (102), the second electrode layer (120) covers part of the second surface (102), and the first electrode layer (110) is located on the second surface (102). The projection of the first dielectric layer (100) overlaps with the projection of the second electrode layer (120) on the first dielectric layer (100), and the second electrode layer (120) and the second annular The conductive sheet (520) is connected.
The magnetic field enhancement device according to claim 6, characterized in that the orthographic projection of the first electrode layer (110) on the first dielectric layer (100) and the second electrode layer (120) on the The area occupied by the orthographic overlapping portion of the first dielectric layer (100) is less than half of the area of the first surface (101) or half of the area of the second surface (102).
The magnetic field enhancement device according to claim 6, characterized in that, the first electrode layer (110) and the second electrode layer (120) are located at the part where the projection of the first dielectric layer (100) overlaps. the middle of the first dielectric layer (100).
The magnetic field enhancement device of claim 8, further comprising:

A third electrode layer (130) is disposed on the first surface (101) and is spaced apart from the first electrode layer (110), and the first dielectric layer (100) includes opposite first ends (103) and a second end (104), the third electrode layer (130) extends from the first end (103) to the second end (104) and covers part of the first surface (101), so The second electrode layer (120) is electrically connected to the third electrode layer (130).
The magnetic field enhancement device according to claim 6, characterized in that, one end of the first electrode layer (110) close to the second electrode layer (120) has a first gap (411), and the second electrode layer (120) One end close to the first electrode layer (110) has a second notch (412), and the first notch (411) and the second notch (412) are in the first dielectric layer (100) The orthographic projections of .
The magnetic field enhancement device according to claim 6, wherein the magnetic field enhancement component further comprises a first external capacitor (440), and two ends of the first external capacitor (440) are respectively connected to the first electrode layer (110) is connected to the second electrode layer (120).
The magnetic field enhancement device according to claim 6, further comprising a first switch control circuit (430), two ends of the first switch control circuit (430) being respectively connected to the first electrode layer (110) Connected to the second electrode layer (120), the first switch control circuit (430) is configured to be turned on in the radio frequency transmitting stage and disconnected in the radio frequency receiving stage.
The magnetic field enhancement device according to claim 11, wherein one end of the first switch control circuit (430) is connected to the first electrode layer (110) and the second electrode layer (120) where the first electrode layer (110) is located. The orthographic projections of the first dielectric layer (100) have overlapping portions.
The magnetic field enhancement device according to claim 1, characterized in that, a plurality of the magnetic field enhancement components are arranged on the sidewall of the cylindrical support structure (50) at equal intervals.
The magnetic field enhancement device according to claim 1, characterized in that, at the third end (51), the magnetic field enhancement component is sandwiched between the cylindrical support structure (50) and the first annular conductive sheet Between (510), at the fourth end (53), the magnetic field enhancement component is sandwiched between the cylindrical support structure (50) and the second annular conductive sheet (520).
A curved magnetic field enhancement device, characterized in that it includes:

a flexible support body (500), the flexible support body (500) can be bent into a curved surface;

A plurality of magnetic field enhancement assemblies are arranged on the flexible support body (500) in parallel and spaced apart, each of the magnetic field enhancement assemblies includes a first electrical connection end (911) and a second electrical connection end (912), the first electrical connection end (912). A structure capacitor and an inductance structure connected in series are connected between the connection end (911) and the second electrical connection end (912);

a first conductive sheet (510), respectively connected to the first electrical connection ends (911) of the plurality of magnetic field enhancement components;

The second conductive sheets (520) are respectively connected to the second electrical connection ends (912) of the plurality of magnetic field enhancement components, and the resonance frequency of the curved magnetic field enhancement components (20) is equal to the target frequency.
The curved magnetic field enhancement device according to claim 16, characterized in that the inductance value of the inductance structure in the magnetic field enhancement component at the edge of the curved magnetic field enhancement device (20) is greater than that in the middle of the curved magnetic field enhancement device (20). The inductance value of the inductive structure in the magnetic field enhancement component.
The curved magnetic field enhancement device according to claim 16, characterized in that, the capacitance values of the magnetic field enhancement components in the curved magnetic field enhancement device (30) are all the same, and the inductance values are all the same.
The curved magnetic field enhancement device of claim 16, further comprising:

an output matching circuit (640), the output matching circuit (640) is connected to the first electrical connection terminal (911), the output matching circuit (640) is also used for connecting with a signal acquisition device, the output matching circuit (640) is used to adjust the impedance value and resonant frequency of the signal acquisition device.
The curved magnetic field enhancement device according to claim 19, wherein the output matching circuit (640) further comprises:

a matching capacitor (641), one end of the matching capacitor (641) is connected to the positive electrode of the first electrical connection terminal (911);

a tuning capacitor (642), the tuning capacitor (642) is connected between the other end of the matching capacitor (641) and the negative electrode of the first electrical connection end (911);

An output interface (643), the output interface (643) is connected in parallel with the tuning capacitor (642), and the output interface (643) is used for connecting with the signal acquisition device.
The curved magnetic field enhancement device of claim 20, further comprising:

A second switch circuit (650), the second switch circuit (650) includes a first depletion MOS transistor (652) and a second depletion MOS transistor (653) connected in reverse series, the first depletion MOS transistor (653) The gate and drain of the first depletion MOS transistor (652) are connected to the end of the matching capacitor (641) away from the tuning capacitor (642), and the source of the first depletion MOS transistor (652) is connected to the The source of the second depletion MOS transistor (653) is connected, the gate and drain of the second depletion MOS transistor (653) are connected to the positive electrode of the first electrical connection terminal (911), the The first depletion MOS transistor (652) and the second depletion MOS transistor (653) are used for alternately conducting in the radio frequency receiving stage, and the first depletion MOS transistor (652) and the second depletion MOS transistor (652) A depletion-mode MOS transistor (653) is used to open the circuit during the RF transmission stage.
The curved magnetic field enhancement device according to claim 20, wherein the output matching circuit (640) is connected to the magnetic field enhancement component located in the middle of the curved magnetic field enhancement device (20).
The curved magnetic field enhancement device according to claim 16, wherein the magnetic field enhancement component comprises:

a first dielectric layer (100) having opposing first (103) and second (104) ends and including opposing first (101) and second surfaces (102);

A first electrode layer (110), disposed on the first surface (101) and extending along the first end (103) to the second end (104), the first electrode layer (110) comprising a first sub-electrode layer (111), a second sub-electrode layer (112) and a first connection layer (190), the width of the first sub-electrode layer (111) and the second sub-electrode layer (112) Equally and relatively spaced apart, one end of the first connection layer (190) is connected to the first sub-electrode layer (111), and the other end of the first connection layer (190) is connected to the second sub-electrode layer (112) connection, the width of the first connection layer (190) is smaller than the width of the first sub-electrode layer (111);

The second electrode layer (120) and the third electrode layer (130) are disposed on the second surface (102) at a relative interval, and the second electrode layer (120) is on the positive side of the first dielectric layer (100). The projection overlaps with the orthographic projection of the first sub-electrode layer (111) on the first dielectric layer (100) to form a second structural capacitor (152), and the third electrode layer (130) is in the first dielectric layer (100). The orthographic projection of a dielectric layer (100) overlaps with the orthographic projection of the first sub-electrode layer (111) on the first dielectric layer (100) to form a third structural capacitor (153);

A first tuning circuit (60), one end of the first tuning circuit (60) is connected to the first sub-electrode layer (111), and the other end of the first tuning circuit (60) is connected to the second electrode The layer (120) is connected, the first tuning circuit (60) is used to make the curved magnetic field enhancement device (20) resonate when it is in a radio frequency receiving stage, and the first tuning circuit (60) is used to make the curved magnetic field Tuning when the boosting device (20) is in the radio frequency transmitting stage;

The second structural capacitor (152) is the first electrical connection terminal (911), the third structural capacitor (153) is the second electrical connection terminal (912), and the first conductive sheet (510) ) are respectively connected to the first sub-electrode layers (111) of the plurality of magnetic field enhancement components, and the second conductive sheets (520) are respectively connected to the second electrode layers (120) of the magnetic field enhancement components )connect.
The curved magnetic field enhancement device according to claim 23, wherein the first tuning circuit (60) further comprises an external capacitor (440), and two ends of the external capacitor (440) are respectively connected to the first sub-connector The electrode layer (111) is connected to the second electrode layer (120).
The curved magnetic field enhancement device according to claim 23, characterized in that, the included angle between the extending direction of the first connection layer (190) and the first direction is an acute angle or an obtuse angle, and the first direction is defined by the first direction. The end (103) points to the second end (104).
The curved magnetic field enhancement device according to claim 23, wherein the intersection of the side wall of the first connection layer (190) and the side wall of the first sub-electrode layer (111) is set as an arc-shaped inverted horn.
The curved magnetic field enhancement device according to claim 23, wherein the electrical loss ratio of the first connection layer (190) is less than 1/2 of the overall electrical loss of the magnetic field enhancement component.
The curved magnetic field enhancement device according to claim 23, wherein the width of the first connection layer (190) is 1/5 to 1/2 of the width of the first sub-electrode layer (111).
The curved magnetic field enhancement device according to claim 23, wherein the first tuning circuit (60) comprises:

A first diode (431) and a second diode (432), the anode of the first diode (431) is connected to the first sub-electrode layer (111), the first diode (432) The cathode of (431) is connected to the second electrode layer (120), the cathode of the second diode (432) is connected to the first sub-electrode layer (111), and the second diode ( 432) is connected to the second electrode layer (120).