WO2022170753A1 - 一种双核mri的图像增强超构表面器件 - Google Patents

一种双核mri的图像增强超构表面器件 Download PDF

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Publication number
WO2022170753A1
WO2022170753A1 PCT/CN2021/114228 CN2021114228W WO2022170753A1 WO 2022170753 A1 WO2022170753 A1 WO 2022170753A1 CN 2021114228 W CN2021114228 W CN 2021114228W WO 2022170753 A1 WO2022170753 A1 WO 2022170753A1
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WIPO (PCT)
Prior art keywords
magnetic field
electrode layer
field enhancement
capacitor
cylindrical
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PCT/CN2021/114228
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English (en)
French (fr)
Inventor
赵乾
池中海
孟永钢
郑卓肇
易懿
王亚魁
Original Assignee
清华大学
北京清华长庚医院
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Priority claimed from CN202110183916.5A external-priority patent/CN114910839B/zh
Priority claimed from CN202110183943.2A external-priority patent/CN114910850B/zh
Application filed by 清华大学, 北京清华长庚医院 filed Critical 清华大学
Publication of WO2022170753A1 publication Critical patent/WO2022170753A1/zh

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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Measuring for diagnostic purposes; Identification of persons
    • A61B5/05Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves 
    • A61B5/055Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00Arrangements or instruments for measuring magnetic variables
    • G01R33/20Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/32Excitation or detection systems, e.g. using radio frequency signals
    • G01R33/34Constructional details, e.g. resonators, specially adapted to MR

Definitions

  • the present application relates to the technical field of magnetic resonance imaging, and in particular, to a dual-core magnetic field enhancement device applied to an MRI system and a magnetic resonance system.
  • Magnetic resonance imaging Magnetic Resonance Imaging, MRI
  • MRI Magnetic Resonance Imaging
  • the signal intensity transmitted by traditional MRI systems mainly comes from the hydrogen proton 1 H.
  • the hydrogen proton 1 H has the highest content in the human body, and the hydrogen proton 1 H has the highest gyromagnetic ratio and the strongest NMR signal.
  • MRI based on hydrogen proton 1 H contains less biological information such as metabolism and ion exchange, while aprotic nuclei such as 23 Na, 31 P, and 19 F can provide rich biological information. Therefore, imaging based on 23 Na, 31 P, 19 F and other aprotic nuclei has important research significance in medical and life science research.
  • the signal-to-noise ratio is mainly determined by the strength of the static magnetic field.
  • 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 dizziness and vomiting and other adverse reactions: 3)
  • the purchase cost has increased significantly, which is a burden for 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.
  • Metamaterials have special properties that many natural materials do not possess.
  • the working principle is to use the electromagnetic resonance in the structure formed by metamaterials to realize the adjustment of electromagnetic parameters such as anisotropy and gradient distribution.
  • parameters such as geometric size, shape and dielectric constant of metamaterials, resonance enhancement at different frequency points can be achieved.
  • the present application provides a dual-nuclear magnetic field enhancement device and a magnetic resonance system.
  • the present application provides a dual-core magnetic field enhancement device.
  • the dual-core magnetic field enhancement device includes a first cylindrical magnetic field intensifier and a second cylindrical magnetic field intensifier.
  • the first cylindrical magnetic field enhancer surrounds and forms a first accommodating space.
  • the first cylindrical magnetic field enhancer is used to enhance the nuclear magnetic signal of the hydrogen proton nucleus at the detection site.
  • the second cylindrical magnetic field enhancer is arranged in the first accommodating space and is used to enhance the nuclear magnetic signal of the non-hydrogen proton nucleus in the detection site.
  • the second cylindrical magnetic field intensifier surrounds and forms a second accommodating space for accommodating the detection site.
  • the first cylindrical magnetic field intensifier and the second cylindrical magnetic field intensifier are used to detect different target nuclei in the same part, and can show that the different target nuclei in the detection part correspond to each other MRI imaging information.
  • the second cylindrical magnetic field enhancer is arranged in the first accommodating space.
  • the second cylindrical magnetic field enhancer is arranged inside the dual-core magnetic field enhancement device.
  • the first cylindrical magnetic field enhancer is arranged outside the dual-core magnetic field enhancement device.
  • the second cylindrical magnetic field intensifier is nested with the first cylindrical magnetic field intensifier.
  • the dual-nuclear magnetic field enhancement device can enhance the nuclear magnetic signal of the hydrogen proton nucleus and the nuclear magnetic signal of the non-hydrogen proton nucleus in the detection site.
  • the dual-nuclear magnetic field enhancement device realizes the simultaneous enhancement of the two signal fields of the hydrogen proton nucleus and the non-hydrogen proton nucleus of the dual nucleus MRI.
  • the dual-core magnetic field enhancement device can have a higher magnetic field enhancement effect.
  • the dual-core magnetic field enhancement device can assist the MRI system to obtain higher-quality images.
  • FIG. 1 is a schematic structural diagram of a first cylindrical magnetic field intensifier and a second cylindrical magnetic field intensifier in the dual-core magnetic field intensifier device provided by the application.
  • FIG. 2 is a schematic diagram of the overall structure of the dual-core magnetic field enhancement device provided by the present application.
  • FIG. 3 is a schematic structural diagram of a first cylindrical support provided by the present application.
  • FIG. 4 is a schematic structural diagram of a second cylindrical support provided by the present application.
  • FIG. 5 is a schematic diagram of the connection between the first resonance control circuit and the external magnetic field enhancement component provided in the present application.
  • FIG. 6 is a schematic diagram of the connection between the second resonance control circuit and the internal magnetic field enhancement component provided by the present application.
  • FIG. 7 is a schematic diagram of an exploded structure of a first cylindrical support, a first annular conductive sheet, and a second annular conductive sheet in an embodiment provided by the present application.
  • FIG. 8 is a side view of the first annular conductive sheet, the second annular conductive sheet and the first phase adjustment gap shown in FIG. 51 provided by the present application.
  • FIG. 9 is a diagram of a vertical relationship between an induction field and a regulation gap provided by an embodiment of the present application.
  • FIG. 10 is a schematic diagram of a resonance effect provided by an embodiment of the present application.
  • FIG. 11 is an internal magnetic field distribution diagram of a first cylindrical magnetic field intensifier according to an embodiment of the present application.
  • FIG. 12 is a schematic diagram of an exploded structure of a second cylindrical support, a third annular conductive sheet, and a fourth annular conductive sheet in an embodiment provided by the application.
  • FIG. 13 is a schematic diagram of the positional relationship between the third phase regulation gap and the first phase regulation gap provided by the present application.
  • FIG. 14 is a schematic diagram of the resonance frequency of a dual-core magnetic field enhancement device in an embodiment provided by the present application.
  • FIG. 15 is a side view of the first magnetic field enhancement component in one embodiment provided by the application.
  • FIG. 16 is a top view of the first magnetic field enhancement assembly in FIG. 15 .
  • FIG. 17 is a side view of a first magnetic field enhancement component provided by an embodiment of the present application.
  • FIG. 18 is a side view of a first magnetic field enhancement component provided by an embodiment of the present application.
  • FIG. 19 is a side view of a first magnetic field enhancement component provided by an embodiment of the present application.
  • FIG. 20 is a side view of a second magnetic field enhancement component provided by an embodiment of the present application.
  • FIG. 21 is a top view of a second magnetic field enhancement component according to an embodiment of the present application.
  • FIG. 22 is a bottom view of a second magnetic field enhancement component provided by an embodiment of the present application.
  • FIG. 23 is a structural diagram of a second magnetic field enhancement component according to an embodiment of the present application.
  • FIG. 24 is a frequency comparison diagram of the second magnetic field enhancement component in a radio frequency transmitting stage and a radio frequency receiving stage according to an embodiment of the present application.
  • FIG. 24 is a frequency comparison diagram of the second magnetic field enhancement component in a radio frequency transmitting stage and a radio frequency receiving stage according to an embodiment of the present application.
  • FIG. 25 is a comparison diagram of the effects of the second magnetic field enhancement component provided by an embodiment of the present application.
  • FIG. 26 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 27 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 28 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 29 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 30 is a frequency comparison diagram of the second magnetic field enhancement component in a radio frequency transmitting stage and a radio frequency receiving stage according to an embodiment of the present application.
  • FIG. 31 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 32 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 33 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 34 is a frequency comparison diagram of a second magnetic field enhancement component in a radio frequency transmitting stage and a radio frequency receiving stage according to an embodiment of the present application.
  • FIG. 35 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 36 is a structural diagram of a second magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 37 is a side view of a third magnetic field enhancement component provided by another embodiment of the present application.
  • FIG. 38 is a top view of a third magnetic field enhancement component according to an embodiment of the present application.
  • FIG. 39 is a bottom view of a third magnetic field enhancement component provided by an embodiment of the present application.
  • FIG. 40 is a schematic diagram of an orthographic projection of the first electrode layer and the second electrode layer on the first dielectric layer according to an embodiment of the present application.
  • FIG. 41 is a schematic diagram of the orthographic shape of the first electrode layer and the second electrode layer on the first dielectric layer according to another embodiment of the present application.
  • FIG. 42 is a side view of the fourth magnetic field enhancement component provided in one embodiment of the application.
  • FIG. 43 is a top view of the embodiment in FIG. 35 of the application.
  • 44 is a side view of a fourth magnetic field enhancement assembly in one embodiment provided by the application.
  • FIG. 45 is a schematic diagram of an exploded structure of the fourth magnetic field enhancement component in the embodiment of FIG.
  • FIG. 46 is a top view of the fourth magnetic field enhancement component in the embodiment of FIG. 44 provided in this application.
  • 47 is a side view of a fifth magnetic field enhancement assembly in one embodiment provided by the application.
  • FIG. 48 is a schematic structural diagram of the fifth magnetic field enhancement component in the embodiment of FIG. 37 provided by this application.
  • FIG. 49 is a top view of a fifth magnetic field enhancement component in an embodiment provided by the application.
  • FIG. 50 is a bottom view of the fifth magnetic field enhancement assembly in one embodiment provided by the application.
  • Figure 51 is a side view of a fifth magnetic field enhancement assembly in one embodiment provided by the application.
  • Figure 52 is a side view of a fifth magnetic field enhancement assembly in one embodiment provided by the application.
  • Figure 53 is a side view of a fifth magnetic field enhancement assembly in one embodiment provided by the application.
  • FIG. 54 is a top view of a second via hole in an embodiment provided by the present application.
  • FIG. 55 is a side view of a sixth magnetic field enhancement component in an embodiment provided by the application.
  • 56 is a side view of a sixth magnetic field enhancement assembly in one embodiment provided by the application.
  • FIG. 57 is a schematic diagram of the resonance frequency of a dual-core magnetic field enhancement device in an embodiment provided by the present application.
  • the present application provides a dual-core magnetic field enhancement device 30 .
  • the dual-core magnetic field intensifier 30 includes a first cylindrical magnetic field intensifier 810 and a second cylindrical magnetic field intensifier 820 .
  • the first cylindrical magnetic field enhancer 810 surrounds and forms a first accommodating space 819 .
  • the first cylindrical magnetic field enhancer 810 is used to enhance the nuclear magnetic signal of the hydrogen proton nucleus at the detection site.
  • the second cylindrical magnetic field enhancer 820 is disposed in the first accommodating space 819 .
  • the second cylindrical magnetic field enhancer 820 surrounds and forms a second accommodating space 829 .
  • the detection part can be accommodated in the second accommodating space 829 .
  • the second cylindrical magnetic field enhancer 820 is used to enhance the nuclear magnetic signal of the non-hydrogen proton nucleus at the detection site.
  • the first accommodating space 819 is larger than the second accommodating space 829 .
  • the detection part is accommodated in the second accommodating space 829 , it is also accommodated in the first accommodating space 819 at the same time.
  • the first accommodating space 819 surrounds the second accommodating space 829 .
  • the second accommodating space 829 surrounds the detection site.
  • the detection part is located in the first accommodating space 819 and the second accommodating space 829 at the same time.
  • the detection site may be an arm, a leg, or an abdomen of a human or an animal.
  • the detection site includes a hydrogen proton nucleus and a non-hydrogen proton nucleus other than the hydrogen proton nucleus.
  • Non-hydrogen proton nuclei include 23 Na, 31 P, 19 F, and the like.
  • Non-hydrogen proton nuclei can provide rich biological information such as metabolism and ion exchange.
  • the diameter of the first cylindrical magnetic field intensifier 810 is larger than the diameter of the second cylindrical magnetic field intensifier 820 .
  • the first cylindrical magnetic field intensifier 810 is nested outside the second cylindrical magnetic field intensifier 820 .
  • the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 are used to detect different target nuclei in the same part, and can display MRI imaging information corresponding to different target nuclei in the detection part.
  • the second cylindrical magnetic field enhancer 820 is disposed in the first accommodating space 819 .
  • the second cylindrical magnetic field intensifier 820 is disposed inside the dual-core magnetic field intensifier 30 .
  • the first cylindrical magnetic field intensifier 810 is disposed outside the dual-core magnetic field intensifier 30 .
  • the second cylindrical magnetic field intensifier 820 is nested with the first cylindrical magnetic field intensifier 810 .
  • the dual-nuclear magnetic field enhancement device 30 can enhance the nuclear magnetic signal of hydrogen proton nuclei and the nuclear magnetic signal of non-hydrogen proton nuclei in the detection site.
  • the binuclear magnetic field enhancement device 30 realizes the simultaneous enhancement of the two signal fields of the hydrogen proton nucleus and the non-hydrogen proton nucleus of the binuclear MRI.
  • the dual-core magnetic field enhancement device 30 can have a higher magnetic field enhancement effect. When applied to MRI system imaging, the dual-core magnetic field enhancement device 30 can assist the MRI system to obtain higher-quality images.
  • the dual-core magnetic field enhancement device 30 is a dual-core MRI image-enhancing metasurface device.
  • the image-enhanced metasurface device of the dual-core MRI can enhance the nuclear magnetic signal of the hydrogen proton nucleus and the nuclear magnetic signal of the non-hydrogen proton nucleus in the detection site.
  • the image-enhanced metasurface device of the dual-core MRI realizes the simultaneous enhancement of two signal fields of the hydrogen proton nucleus and the non-hydrogen proton nucleus of the dual-core MRI.
  • the diameter and length of the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 may be determined according to the detection site. In one embodiment, the length of the first cylindrical magnetic field enhancer 810 is 350 mm. The diameter of the first cylindrical magnetic field enhancer 810 is 120 mm. The diameter of the second cylindrical magnetic field enhancer 820 is 100 mm. The length of the second cylindrical magnetic field enhancer 820 is 450 mm.
  • the first cylindrical magnetic field intensifier 810 includes a first cylindrical support 811 and a plurality of external magnetic field intensifier components 812 .
  • the first cylindrical bracket 811 has a first outer surface 801 and a first inner surface 802 .
  • the first outer surface 801 surrounds the first inner surface 802 .
  • the first outer surface 801 is disposed opposite to the first inner surface 802 at intervals.
  • the first inner surface 802 surrounds the first accommodating space 819 .
  • the extension direction of the external magnetic field enhancement component 812 is the same as the extension direction of the first central axis of the first cylindrical support 811 .
  • the external magnetic field enhancement components 812 are disposed on the first outer surface 801 at intervals around the first central axis of the first cylindrical bracket 811 .
  • Each of the external magnetic field enhancing components 812 has oppositely disposed first and second ends.
  • the first ends of the plurality of external magnetic field enhancing components 812 are connected in sequence.
  • the first ends of the plurality of external magnetic field enhancing components 812 are electrically connected one by one along the direction around the first central axis.
  • the second ends of the plurality of external magnetic field enhancing components 812 are connected in sequence.
  • the second ends of the plurality of external magnetic field enhancing components 812 are electrically connected one by one along a direction surrounding the first central axis of the first cylindrical bracket 811 .
  • the nuclear magnetic signal of the hydrogen proton nucleus at the detection site can be enhanced, which is beneficial to the imaging of the MRI system.
  • the first cylindrical magnetic field enhancer 810 further includes a first annular conductive sheet 861 , a second annular conductive sheet 862 and a first fixing structure 883 .
  • the first annular conductive sheet 861 and the second annular conductive sheet 862 are respectively disposed at opposite ends of the first cylindrical support 811 .
  • the first cylindrical bracket 811 has a first end and a second end opposite to each other along the direction of the first central axis. The direction from the first end to the second end of the first cylindrical support 811 is the same as the direction of the first central axis of the first cylindrical support 811 .
  • the first annular conductive sheet 861 is disposed on the first end of the first cylindrical support 811 .
  • the second annular conductive sheet 862 is disposed on the second end of the first cylindrical support 811 .
  • the first annular conductive sheet 861 is disposed around the first central axis of the first cylindrical support 811 . It can also be understood that the first center axis passes through the geometric center point of the first annular conductive sheet 861 .
  • the second annular conductive sheet 862 is disposed around the first central axis of the first cylindrical support 811 . It can also be understood that the first center axis passes through the geometric center point of the second annular conductive sheet 862 .
  • each of the external magnetic field enhancing components 812 may be a strip-shaped structure extending along the direction of the second central axis. Two ends of each of the external magnetic field enhancement components 812 are respectively connected to the first annular conductive sheet 861 and the second annular conductive sheet 862 . It can also be understood that each of the external magnetic field enhancing components 812 has a first end and a second end opposite to each other. The direction from the first end to the second end of the internal magnetic field enhancement component 822 is the same as the direction of the second central axis.
  • the first ends of the plurality of external magnetic field enhancement components 812 are sequentially connected through the first annular conductive sheet 861 .
  • the second ends of the plurality of external magnetic field enhancing components 812 are sequentially connected through the second annular conductive sheet 862 .
  • the plurality of external magnetic field enhancement components 812 are connected and fixed by the first cylindrical support 811 , the first annular conductive sheet 861 and the second annular conductive sheet 862 .
  • the first annular conductive sheet 861 is a closed ring.
  • the first annular conductive sheet 861 connects the first ends of the plurality of external magnetic field enhancement components 812 in sequence to form a closed structure.
  • the second annular conductive sheet 862 is a closed ring.
  • the second annular conductive sheet 862 connects the second ends of the plurality of external magnetic field enhancement components 812 in sequence to form a closed structure.
  • the first cylindrical magnetic field enhancer 810 further includes a plurality of first fixing structures 883 .
  • the plurality of first fixing structures 883 are arranged at intervals around the first central axis of the first cylindrical bracket 811 .
  • the plurality of first fixing structures 883 are disposed on the first outer surface 801 .
  • the plurality of first fixing structures 883 are disposed on both ends of the first cylindrical bracket 811 at intervals.
  • Each of the external magnetic field enhancing components 812 corresponds to the first fixing structure 883 at the first end of the first cylindrical support 811 and the first fixing structure at the second end of the first cylindrical support 811 respectively 883.
  • One of the external magnetic field enhancing components 812 is fixed by the first fixing structures 883 at both ends of the first cylindrical bracket 811 .
  • the external magnetic field enhancing component 812 is fixed to the first outer surface 801 of the first cylindrical bracket 811 .
  • the plurality of first fixing structures 883 may be through grooves.
  • the through slot can be used to insert the external magnetic field enhancement component 812 .
  • Each two of the first fixing structures 883 respectively fix both ends of the external magnetic field enhancing component 812 .
  • the external magnetic field enhancing assembly 812 can be fixed to the first outer surface 801 of the first cylindrical bracket 811 by the first fixing structure 883 .
  • first annular conductive sheet 861 and the second annular conductive sheet 862 may be made of metal materials such as gold, silver, and copper.
  • the length of the external magnetic field enhancing component 812 may be 150mm to 400mm. In one embodiment, the length of the external magnetic field enhancement component 812 is 250 mm.
  • the first cylindrical bracket 811 has a first inner surface 802 .
  • the first inner surface 802 surrounds the first accommodating space 819 .
  • the first inner surface 802 is spaced apart from the first outer surface 801 .
  • the first outer surface 801 is disposed around the first inner surface 802 .
  • the second cylindrical magnetic field intensifier 820 includes a second cylindrical support 821 and a plurality of internal magnetic field intensifier components 822 .
  • the second cylindrical bracket 821 is disposed in the first accommodating space 819 .
  • the second cylindrical bracket 821 has a second outer surface 803 and a second inner surface 804 .
  • the second outer surface 803 is disposed opposite to the first inner surface 802 at intervals.
  • the plurality of internal magnetic field enhancement components 822 are disposed on the second outer surface 803 at equal intervals.
  • the plurality of internal magnetic field enhancement components 822 are disposed between the second outer surface 803 and the first inner surface 802 .
  • the extending direction of the internal magnetic field enhancing component 822 is the same as the extending direction of the second central axis of the second cylindrical bracket 821 .
  • the direction from the first end of the second cylindrical support 821 to the second end of the second cylindrical support 821 is the same as the direction of the second central axis.
  • Each of the internal magnetic field enhancement components 822 has a first end and a second end opposite to each other, and the first ends of the plurality of internal magnetic field enhancement components 822 are connected in sequence.
  • the second ends of the plurality of internal magnetic field enhancement components 822 are connected in sequence.
  • the second inner surface 804 surrounds and forms a second accommodating space 829 .
  • the second accommodating space 829 is used to place the detection site, such as arms, legs, abdomen, and the like.
  • the first ends of the plurality of internal magnetic field enhancing components 822 are electrically connected one by one along a direction around the second central axis.
  • the second ends of the plurality of internal magnetic field enhancing components 822 are electrically connected one by one along a direction around the second central axis.
  • the plurality of internal magnetic field enhancing components 822 are connected through the first end and the second end to form a resonant circuit with its specific resonant frequency.
  • the resonant frequency of the resonant circuit formed by the plurality of internal magnetic field enhancement components 822 is the same as the working frequency, the nuclear magnetic signal of the non-hydrogen proton nucleus at the detection site can be enhanced, which is beneficial to the imaging of the MRI system .
  • the second cylindrical magnetic field enhancer 820 further includes a third annular conductive sheet 866 , a fourth annular conductive sheet 867 and a second fixing structure 884 .
  • the third annular conductive sheet 866 and the fourth annular conductive sheet 867 are respectively disposed at opposite ends of the second cylindrical support 821 .
  • the second cylindrical support 821 has a first end and a second end opposite to each other along the direction of the second central axis.
  • the third annular conductive sheet 866 is disposed on the first end of the second cylindrical support 821 .
  • the fourth annular conductive sheet 867 is disposed on the second end of the second cylindrical support 821 .
  • the third annular conductive sheet 866 is disposed around the second central axis of the second cylindrical support 821 . It can also be understood that the second center axis passes through the geometric center point of the third annular conductive sheet 866 .
  • the fourth annular conductive sheet 867 is disposed around the second central axis of the second cylindrical support 821 . It can also be understood that the second center axis passes through the geometric center point of the fourth annular conductive sheet 867 .
  • each of the internal magnetic field enhancing components 822 may be a strip-like structure extending along the direction of the second central axis. Two ends of each of the internal magnetic field enhancement components 822 are respectively connected to the third annular conductive sheet 866 and the fourth annular conductive sheet 867 . It can also be understood that each of the internal magnetic field enhancing components 822 has a first end and a second end opposite to each other. The first ends of the plurality of internal magnetic field enhancement components 822 are sequentially connected through the third annular conductive sheet 866 . The second ends of the plurality of internal magnetic field enhancement components 822 are sequentially connected through the fourth annular conductive sheet 867 . The plurality of internal magnetic field enhancement components 822 are connected and fixed by the second cylindrical support 821 , the third annular conductive sheet 866 and the fourth annular conductive sheet 867 .
  • the third annular conductive sheet 866 is a closed ring.
  • the third annular conductive sheet 866 connects the first ends of the plurality of internal magnetic field enhancement components 822 in sequence to form a closed structure.
  • the fourth annular conductive sheet 867 is a closed ring.
  • the fourth annular conductive sheet 867 connects the second ends of the plurality of internal magnetic field enhancing components 822 in sequence to form a closed structure.
  • the second cylindrical magnetic field enhancer 820 further includes a plurality of second fixing structures 884 .
  • the plurality of second fixing structures 884 are disposed on the second outer surface 803 at intervals around the second central axis of the second cylindrical bracket 821 .
  • the plurality of second fixing structures 884 are arranged at intervals at both ends.
  • Each of the internal magnetic field enhancing components 821 corresponds to the second fixing structure 884 at the first end of the second cylindrical support 821 and the second fixing structure at the second end of the second cylindrical support 821 respectively 884.
  • One of the internal magnetic field enhancement components 822 is fixed by the second fixing structures 884 at both ends of the second cylindrical bracket 821 .
  • the internal magnetic field enhancing component 82 is fixed to the second outer surface 803 of the second cylindrical bracket 821 .
  • the plurality of second fixing structures 884 may be through grooves.
  • the through slot can be used to insert the internal magnetic field enhancement component 822 .
  • Each two of the second fixing structures 884 respectively fix both ends of the internal magnetic field enhancing component 822 .
  • the internal magnetic field enhancement assembly 822 can be fixed to the second outer surface 803 of the second cylindrical bracket 821 by the second fixing structure 884 .
  • the dual-core magnetic field enhancement device 30 further includes a plurality of first resonance control circuits 851 .
  • One of the first resonance control circuits 851 is electrically connected to one of the external magnetic field enhancement components 812 for controlling the working state of the external magnetic field enhancement components 812.
  • the working states of the external magnetic field enhancing component 812 include a detuning state and a resonance state.
  • the detuned state means that in the radio frequency transmission stage of the MRI system, the first resonance control circuit 851 controls the resonant circuit in which the external magnetic field enhancement component 812 is located to not resonate and present a detuned state.
  • the resonance state means that in the radio frequency receiving stage of the MRI system, the first resonance control circuit 851 adjusts its own electronic components such as capacitance and inductance, so that the resonance circuit in which the external magnetic field enhancement component 812 is located is in a resonance state.
  • the resonance frequency of the resonance circuit is the same as the working frequency, which can enhance the nuclear magnetic signal of the hydrogen proton nucleus at the detection site, which is beneficial to the imaging of the MRI system.
  • Figure 5 is a schematic connection diagram.
  • the connection position of the first resonance control circuit 851 and the external magnetic field enhancement component 812 can be changed according to the circuit structure described in any one of the following embodiments.
  • the first resonance control circuit 851 includes the circuit structure described in any one of the following embodiments, and is used for regulating the resonance state.
  • the dual-core magnetic field enhancement device 30 further includes a plurality of second resonance control circuits 852 .
  • One of the second resonance control circuits 852 is electrically connected to one of the internal magnetic field enhancement components 822 for controlling the working state of the internal magnetic field enhancement components 822 .
  • the working states of the internal magnetic field enhancing component 822 include a detuning state and a resonance state.
  • the detuned state means that in the radio frequency transmission stage of the MRI system, the resonant circuit in which the second resonance control circuit 852 is located does not resonate and is in a detuned state.
  • the resonance state means that in the radio frequency receiving stage of the MRI system, the second resonance control circuit 852 controls its own electronic components such as capacitance and inductance, so that the resonance circuit formed by the external magnetic field enhancement component 812 is in a resonance state.
  • the resonance frequency of the resonant circuit is the same as the working frequency, which can enhance the nuclear magnetic signal of the non-hydrogen proton nucleus at the detection site, which is beneficial to the imaging of the MRI system.
  • Figure 6 is a schematic connection diagram.
  • the connection position of the second resonance control circuit 852 and the internal magnetic field enhancement component 822 can be changed according to the circuit structure described in any one of the following embodiments.
  • the second resonance control circuit 852 includes the circuit structure described in any one of the following embodiments, and is used for regulating the resonance state.
  • the first central axis of the first cylindrical magnetic field intensifier 810 coincides with the second central axis of the second cylindrical magnetic field intensifier 820 .
  • the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 have the same central axis, which is beneficial to form a symmetrical and uniform magnetic field around the detection site.
  • the middle section of the first cylindrical magnetic field intensifier 810 coincides with the middle section of the second cylindrical magnetic field intensifier 820 .
  • the middle section of the first cylindrical magnetic field intensifier 810 refers to the cross section at the middle position of the first cylindrical magnetic field intensifier 810 , which is perpendicular to the direction of the central axis.
  • the middle section of the second cylindrical magnetic field intensifier 820 refers to the cross section at the middle position of the second cylindrical magnetic field intensifier 820 , which is perpendicular to the direction of the central axis.
  • the length of the first cylindrical magnetic field intensifier 810 is smaller than the length of the second cylindrical magnetic field intensifier 820 .
  • both ends of the first cylindrical magnetic field intensifier 810 are not coplanar with both ends of the second cylindrical magnetic field intensifier 820 .
  • the first end of the first cylindrical magnetic field intensifier 810 and the first end of the second cylindrical magnetic field intensifier 820 are arranged in a dislocation.
  • the second end of the first cylindrical magnetic field intensifier 810 and the second end of the second cylindrical magnetic field intensifier 820 are arranged in a staggered position.
  • the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 have different lengths, and both ends are not coplanar.
  • the end rings of the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 are staggered.
  • the end rings of the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 are staggered, which avoids the formation of stray capacitance at the port position, and reduces the size of the first cylindrical magnetic field intensifier 810 and the The coupling effect between the second cylindrical magnetic field enhancers 820 .
  • the first end of the first cylindrical magnetic field intensifier 810 and the first end of the second cylindrical magnetic field intensifier 820 differ by at least 20 mm on the same side.
  • the difference between the second end of the first cylindrical magnetic field intensifier 810 and the second end of the second cylindrical magnetic field intensifier 820 is at least 20 mm.
  • the two ends of the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 are dislocated by at least 20 mm, which reduces stray capacitance.
  • the dislocation arrangement of the first cylindrical magnetic field enhancer 810 and the second cylindrical magnetic field enhancer 820 reduces the coupling effect between the two, so that the first cylindrical magnetic field enhancer 810 and the The frequency of the second cylindrical magnetic field intensifier 820 is more stable, which is more conducive to image enhancement of the MRI system.
  • the first annular conductive sheet 861 is disposed around the first central axis of the first cylindrical support 811 .
  • a first phase adjustment gap 871 is formed at the connection between two ends of the first annular conductive sheet 861 .
  • the first phase adjustment gap 871 is formed at the end-to-end proximity.
  • the first phase adjustment notch 871 makes the end of the first annular conductive sheet 861 disconnected.
  • the second annular conductive sheet 862 is disposed around the first central axis of the first cylindrical support 811 .
  • a second phase adjustment gap 872 is formed at the connection between two ends of the second annular conductive sheet 862 .
  • the second phase adjustment gap 872 is formed at the end-to-end proximity.
  • the second phase adjustment notch 872 makes the end of the second annular conductive sheet 862 disconnected.
  • the direction of the induced field generated by the first cylindrical magnetic field intensifier 810 is always perpendicular to the first cylindrical magnetic field intensifier 810 A plane formed by the first central axis of the cylindrical support 811 , the first phase adjustment notch 871 and the second phase adjustment notch 872 .
  • the phase of the induction field is controlled by adjusting the positions of the first phase adjustment notch 871 and the second phase adjustment notch 872, so as to achieve the purpose of accurate detection of the detection site.
  • the first cylindrical magnetic field intensifier 810 is provided with the first phase adjustment notch 871 and the second phase adjustment notch 872, and still has good resonance performance, which can enhance the signal field and improve the image quality.
  • the first annular conductive sheet 861 and the second annular conductive sheet 862 in the first cylindrical magnetic field enhancer 810 have an opening (which can also be understood as an open-loop structure) and the first annular conductive sheet 861 and the second annular conductive sheet 862 Compared with the closed structure of the annular conductive sheet 861 and the second annular conductive sheet 862, the resonance performance of the first cylindrical magnetic field enhancer 810 is not significantly different.
  • the first annular conductive sheet 861 and the second annular conductive sheet 862 have openings, which do not affect the resonance performance of the first cylindrical magnetic field enhancer 810 .
  • the ROI (Region of Interest) region of the inner magnetic field region of the first cylindrical magnetic field intensifier 810 is still highly uniform and will not cause changes in image contrast.
  • the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 of the dual-core magnetic field intensifier 30 of the present application are nested, which improves the magnetic field enhancement effect of the dual-core magnetic field intensifier 30, and further improves the Beneficial for MRI system imaging.
  • the binuclear magnetic field enhancement device 30 can simultaneously enhance the two signal fields of the hydrogen proton nucleus and the non-hydrogen proton nucleus of the binuclear MRI.
  • the second cylindrical magnetic field enhancer 820 enhances the nuclear magnetic signal of the non-hydrogen proton nucleus at the detection site
  • the phase of the induced field can be controlled by the first cylindrical magnetic field enhancer 810 .
  • the first cylindrical magnetic field intensifier 810 controls the phase of the induction field, which can achieve the purpose of accurate detection of the detection part, and is more conducive to the imaging of the MRI system.
  • the dual-core magnetic field enhancement device 30 is an image-enhanced metasurface device based on a dual-core MRI of a phase-regulating metasurface.
  • the dual-core MRI image-enhanced metasurface device based on the phase-regulating metasurface can realize simultaneous enhancement of two signal fields of the hydrogen proton nucleus and the dual nucleus MRI of the non-hydrogen proton nucleus.
  • the dual-core MRI image-enhanced metasurface device based on the phase control metasurface can control the phase of the induction field of the non-hydrogen proton nucleus.
  • the first cylindrical magnetic field intensifier 810 is placed in the magnetic resonance system, it is used to enhance the magnetic field strength in a local area to improve the magnetic resonance detection effect.
  • the plurality of external magnetic field enhancing components 812 may be disposed on the first outer surface 801 at equal intervals.
  • the plurality of external magnetic field enhancement components 812 are arranged at equal intervals, which can improve the uniformity of the local magnetic field.
  • first phase adjustment gap 871 and the second phase adjustment gap 872 are disposed opposite to each other. And the connecting line between the first phase adjustment notch 871 and the second phase adjustment notch 872 is parallel to the first central axis of the first cylindrical support 811 .
  • the first phase adjustment notch 871 , the second phase adjustment notch 872 and the central axis of the first cylindrical support 811 form a plane.
  • the direction of the induced field generated by the first cylindrical magnetic field intensifier 810 is always perpendicular to the first cylindrical support The plane formed by the first central axis of 811 , the first phase adjustment gap 871 and the second phase adjustment gap 872 .
  • first phase adjustment notch 871 Since the first phase adjustment notch 871 , the second phase adjustment notch 872 and the first central axis of the first cylindrical bracket 811 are coplanar, by adjusting the first phase adjustment notch 871 and the second The position of the phase adjustment notch 872 controls the phase of the induction field, so as to achieve the purpose of accurate detection of the detection site.
  • the second cylindrical magnetic field intensifier 820 is nested with the first cylindrical magnetic field intensifier 810 .
  • the central axis of the first phase regulation gap 871 , the second phase regulation gap 872 and the first cylindrical support 811 are coplanar, and will not enhance the non-hydrogen protons of the second cylindrical magnetic field intensifier 820
  • the nuclear NMR signal has an effect. Therefore, it is more favorable to realize the simultaneous enhancement of the two signal fields of the hydrogen proton nucleus and the non-hydrogen proton nucleus of the binuclear MRI.
  • the plurality of external magnetic field enhancement components 812 are disposed on both sides of the connecting line between the first phase adjustment gap 871 and the second phase adjustment gap 872 .
  • the connecting line between the first phase adjustment notch 871 and the second phase adjustment notch 872 is parallel to the first central axis of the first cylindrical bracket 811 .
  • the plurality of external magnetic field enhancement components 812 are symmetrically arranged with respect to the connecting line of the first phase adjustment gap 871 and the second phase adjustment gap 872 .
  • the first phase adjustment gap 871 and the second phase adjustment gap 872 are disposed between two adjacent external magnetic field enhancement components 812 .
  • the head and tail ends of the first annular conductive sheet 861 provided with the first phase adjustment gap 871 protrude toward the gap between two adjacent external magnetic field enhancement components 812.
  • the head and tail ends of the second annular conductive sheet 862 provided with the second phase adjustment notch 872 protrude toward the gap between two adjacent external magnetic field enhancement components 812 .
  • the first phase adjustment notch 871 and the second phase adjustment notch 872 are not disposed on the external magnetic field enhancement component 812, and thus will not affect the external magnetic field enhancement component 812, so that the plurality of external magnetic field enhancement components 812 are not affected.
  • the magnetic field enhanced by the magnetic field enhancement component 812 is more stable and uniform.
  • the first phase adjustment notch 871 and the second phase adjustment notch 872 destroy the isotropic property of the first cylindrical magnetic field intensifier 810 , so that the enhanced magnetic field of the first cylindrical magnetic field intensifier 810 with a specific phase.
  • the phase is controlled by controlling the positions of the first phase adjustment gap 871 and the second phase adjustment gap 872 .
  • the first phase adjustment notch 871 and the second phase adjustment notch 872 are symmetrically arranged with respect to the middle section of the first cylindrical magnetic field enhancer 810 .
  • the middle section of the first cylindrical magnetic field intensifier 810 refers to the cross section at the middle position of the first cylindrical magnetic field intensifier 810 , which is perpendicular to the direction of the central axis.
  • the direction of the induced field generated by the first cylindrical magnetic field intensifier 810 is always parallel to the middle section of the first cylindrical magnetic field intensifier 810 .
  • the first phase regulation notch 871 and the second phase regulation notch 872 are symmetrical with respect to the middle section of the first cylindrical magnetic field intensifier 810 , so that the direction of the induced field generated by the first cylindrical magnetic field intensifier 810 The degree of parallelism with respect to the middle section of the first cylindrical magnetic field enhancer 810 is higher.
  • the third annular conductive sheet 866 is disposed around the second central axis of the second cylindrical support 821 .
  • the second center axis passes through the geometric center point of the third annular conductive sheet 866 .
  • a third phase adjustment gap 873 is formed at the connection between two ends of the third annular conductive sheet 866 .
  • a third phase adjustment gap 873 is formed at the end-to-end proximity.
  • the third phase adjustment notch 873 makes the end of the third annular conductive sheet 866 disconnected.
  • the fourth annular conductive sheet 867 is disposed around the second central axis of the second cylindrical support 821 .
  • the second center axis passes through the geometric center point of the fourth annular conductive sheet 867 .
  • a fourth phase adjustment gap 874 is formed at the connection between two ends of the fourth annular conductive sheet 867 .
  • a fourth phase adjustment gap 874 is formed near the end and the end.
  • the fourth phase adjustment notch 874 makes the head and tail of the fourth annular conductive sheet 867 disconnected.
  • the direction of the induced field generated by the second cylindrical magnetic field intensifier 820 is always perpendicular to the second cylindrical support 821
  • the phase of the induction field is controlled by adjusting the positions of the third phase adjustment notch 873 and the fourth phase adjustment notch 874, so as to achieve the purpose of accurate detection of the detection site.
  • the second cylindrical magnetic field intensifier 820 is provided with the third phase adjustment notch 873 and the fourth phase adjustment notch 874, and still has good resonance performance, which can enhance the signal field and improve the image quality.
  • the ROI (Region of Interest) region of the inner magnetic field region of the second cylindrical magnetic field intensifier 820 is still highly uniform and will not cause changes in image contrast.
  • the dual-nuclear magnetic field enhancement device 30 described in the present application can simultaneously enhance the two signal fields of the dual-nuclear MRI for hydrogen proton nuclei and non-hydrogen proton nuclei.
  • the phase of the corresponding induction field can be adjusted by the first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820, so as to achieve the purpose of accurate detection of the detection part, which is more conducive to the imaging of the MRI system .
  • the third phase adjustment gap 873 and the fourth phase adjustment gap 874 are disposed opposite to each other.
  • the connecting line between the third phase regulating notch 873 and the fourth phase regulating notch 874 is parallel to the second central axis of the second cylindrical support 821 .
  • the third phase adjustment notch 873 , the fourth phase adjustment notch 874 and the second central axis of the second cylindrical support 821 form a plane.
  • the direction of the induced field generated by the second cylindrical magnetic field intensifier 820 is always perpendicular to the second cylindrical support The plane formed by the second central axis of 821 , the third phase adjustment gap 873 and the fourth phase adjustment gap 874 .
  • the third phase adjustment notch 873 and the fourth phase adjustment notch 874 are coplanar, by adjusting the third phase adjustment notch 873 and the fourth phase adjustment notch 873 The position of the phase adjustment gap 874 controls the phase of the induction field, so as to achieve the purpose of accurate detection of the detection site.
  • the second cylindrical magnetic field intensifier 820 is nested with the first cylindrical magnetic field intensifier 810 .
  • the coplanarity of the central axis of the second cylindrical support 821 , the third phase adjustment gap 873 and the fourth phase adjustment gap 874 will not affect the hydrogen proton nuclei enhanced by the first cylindrical magnetic field enhancer 810 .
  • the influence of the nuclear magnetic signal is more conducive to the simultaneous enhancement of the two signal fields of the dual-nuclear MRI.
  • the plurality of internal magnetic field enhancement components 822 are disposed on both sides of the connecting line between the third phase adjustment gap 873 and the fourth phase adjustment gap 874 .
  • the connecting line between the third phase adjustment notch 873 and the fourth phase adjustment notch 874 is parallel to the second central axis of the second cylindrical support 821 .
  • the plurality of internal magnetic field enhancement components 822 are symmetrically arranged with respect to the connection line between the third phase adjustment gap 873 and the fourth phase adjustment gap 874 .
  • the third phase adjustment gap 873 and the fourth phase adjustment gap 874 are disposed between two adjacent internal magnetic field enhancement components 822 .
  • the head and tail ends of the third annular conductive sheet 866 provided with the third phase adjustment notch 873 protrude toward the gap between the two adjacent internal magnetic field enhancement components 822 .
  • the head and tail ends of the fourth annular conductive sheet 867 provided with the fourth phase adjustment notch 874 protrude toward the gap between the two adjacent internal magnetic field enhancement components 822 .
  • the third phase regulation notch 873 and the fourth phase regulation notch 874 are not disposed on the internal magnetic field enhancement component 822, and thus will not affect the internal magnetic field enhancement component 822, so that the second cylinder
  • the magnetic field enhanced by the shaped magnetic field enhancer 820 is stable and uniform.
  • the third phase regulation gap 873 and the fourth phase regulation gap 874 destroy the isotropic properties of the second cylindrical magnetic field intensifier 820, so that the enhanced magnetic field of the second cylindrical magnetic field intensifier 820 with a specific phase.
  • Phase is controlled by controlling the positions of the third phase regulation gap 873 and the fourth phase regulation gap 874.
  • the third phase adjustment gap 873 and the first phase adjustment gap 871 are arranged orthogonally.
  • the included angle between the third phase adjustment notch 873 and the first phase adjustment notch 871 is 90°.
  • the angle between the third phase adjustment gap 873 and the first phase adjustment gap 871 is 90°.
  • the fourth phase adjustment gap 874 is orthogonal to the second phase adjustment gap 872 .
  • the included angle between the fourth phase adjustment gap 874 and the second phase adjustment gap 872 is 90°.
  • the included angle between the fourth phase regulation gap 874 and the second phase regulation gap 872 is 90°.
  • the second cylindrical magnetic field intensifier 820 is nested with the first cylindrical magnetic field intensifier 810 .
  • the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 have phase adjustment gaps arranged orthogonally, so that the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field
  • the phases of the induced magnetic fields generated by the booster 810 are also quadrature.
  • the phase of the induced magnetic field generated by the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 is orthogonal, so that the second cylindrical magnetic field intensifier 820 is in phase with the first cylindrical magnetic field intensifier
  • the coupling effect of the 810 is minimized. Therefore, the dual-core magnetic field enhancement device 30 described in the present application can simultaneously enhance the two signal fields of dual-core MRI.
  • the phase of the induced magnetic field generated by the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 is orthogonal, which reduces the coupling effect and is more conducive to the imaging of the MRI system.
  • the arc lengths of the first phase adjustment notch 871 and the second phase adjustment notch 872 are equal.
  • the arc length of the first phase adjustment gap 871 and the second phase adjustment gap 872 is equal to the distance between two adjacent external magnetic field enhancement components 812 .
  • the arc lengths of the third phase adjustment notch 873 and the fourth phase adjustment notch 874 are equal.
  • the arc length of the third phase adjustment gap 873 and the fourth phase adjustment gap 874 is equal to the distance between two adjacent internal magnetic field enhancement components 822 .
  • the first phase adjustment notch 871 and the second phase adjustment notch 872 are not disposed on the external magnetic field enhancement component 812, and thus will not affect the external magnetic field enhancement component 812, so that all The magnetic field enhanced by the first cylindrical magnetic field intensifier 810 is stable and uniform.
  • the third phase regulation notch 873 and the fourth phase regulation notch 874 are not disposed on the internal magnetic field enhancement component 822, and thus will not affect the internal magnetic field enhancement component 822, so that the second cylinder
  • the magnetic field enhanced by the shaped magnetic field enhancer 820 is stable and uniform.
  • the arc length of the first phase adjustment gap 871 and the second phase adjustment gap 872 is equal to the distance between two adjacent external magnetic field enhancement components 812 .
  • the first ring-shaped conductive sheet 861 and the second ring-shaped conductive sheet 862 will not have excess extension, thereby reducing stray capacitance and reducing the first cylindrical magnetic field enhancer 810 and the second Coupling effect between cylindrical magnetic field enhancers 820.
  • the arc length of the third phase regulation gap 873 and the fourth phase regulation gap 874 is equal to the distance between two adjacent described internal magnetic field enhancement assemblies 822.
  • the third ring-shaped conductive sheet 866 and the fourth ring-shaped conductive sheet 867 will not have redundant parts to extend, thereby reducing stray capacitance and reducing the first cylindrical magnetic field enhancer 810 and the second Coupling effect between cylindrical magnetic field enhancers 820.
  • first cylindrical magnetic field intensifier 810 and the second cylindrical magnetic field intensifier 820 are placed symmetrically on a coaxial line.
  • the first annular conductive sheet 861 and the second annular conductive sheet 862 in the first cylindrical magnetic field enhancer 810 are respectively provided with the first phase adjustment notch 871 and the second phase adjustment notch 872 .
  • the third annular conductive sheet 866 and the fourth annular conductive sheet 867 of the second cylindrical magnetic field intensifier 820 are closed annular structures without a phase adjustment gap.
  • the dual-core magnetic field enhancement device 30 described in the present application has two resonance peaks, and the resonance frequencies are 63.2 MHz and 128.2 MHz respectively. Therefore, the dual-nucleus magnetic field enhancement device 30 can enhance the signal fields of 31 P and 1 H at the same time, can detect different target nuclei in the same part, and can display MRI imaging information corresponding to different target nuclei in the detection part, so as to improve the two image quality.
  • the internal magnetic field enhancement assembly 822 may be the first magnetic field enhancement assembly 310 , the second magnetic field enhancement assembly 320 , the third magnetic field enhancement assembly 330 , the fourth magnetic field enhancement assembly 340 , the fifth magnetic field enhancement assembly 340 in the following embodiments Any one of the magnetic field enhancement component 350 and the sixth magnetic field enhancement component 360.
  • the external magnetic field enhancement component 812 may be the first magnetic field enhancement component 310, the second magnetic field enhancement component 320, the third magnetic field enhancement component 330, the fourth magnetic field enhancement component 340, the fifth magnetic field enhancement component 350, and the first magnetic field enhancement component 350 in the following embodiments. Any one of the six magnetic field enhancement assemblies 360.
  • the first magnetic field enhancement component 310 includes a first dielectric layer 100 , a first electrode layer 110 , a second electrode layer 120 and a first external capacitor 405 .
  • the first dielectric layer 100 includes a first surface 101 and a second surface 102 that are relatively spaced apart.
  • the first dielectric layer 100 has a first end 103 and a second end 104 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 first electrode layer 110 is disposed close to the second end 104 .
  • the second electrode layer 120 is disposed on the first surface 101 .
  • the second electrode layer 120 is spaced apart from the first electrode layer 110 .
  • the second electrode layer 120 covers part of the first surface 101 .
  • the second electrode layer 120 is disposed close to the first end 103 .
  • One end of the first external capacitor 405 is connected to the end of the second electrode layer 120 away from the first end 103 .
  • the other end of the first external capacitor 405 is connected to the end of the first electrode layer 110 away from the second end 104 .
  • the first external capacitor 405 is disposed close to the middle of the first dielectric layer 100 .
  • the first external capacitor 405 may be a fixed capacitor or an adjustable capacitor. After the frequency of the radio frequency coil of the MRI system is determined, an appropriate fixed capacitor can be selected so that the resonant frequency of the second cylindrical magnetic field enhancer 820 is equal to the frequency of the radio frequency coil of the MRI system, thereby enhancing the magnetic field.
  • the first external capacitor 405 may use an adjustable capacitor. The resonant frequency of the second cylindrical magnetic field intensifier 820 can be adjusted by adjusting the adjustable capacitance, so that the second cylindrical magnetic field intensifier 820 is suitable for different environments.
  • one end of the first external capacitor 405 is connected to the end of the first electrode layer 110 close to the second electrode layer 120 .
  • the other end of the first external capacitor 405 is connected to the end of the second electrode layer 120 close to the first electrode layer 110 .
  • the connection position between the first external capacitor 405 and the first electrode layer 110 and the second electrode layer 120 is close to the gap between the first electrode layer 110 and the second electrode layer 120 .
  • the wires connected between the first external capacitor 405 and the first electrode layer 110 and the second electrode layer 120 are relatively short.
  • the connection of the first external capacitor 405 can make the resistance between the first electrode layer 110 and the second electrode layer 120 smaller, thereby reducing the resistance of the first magnetic field enhancement component 310 energy consumption.
  • the width of the first electrode layer 110 is smaller than the width of the first dielectric layer 100 along the direction surrounding the second central axis of the second cylindrical support 821 .
  • the width of the second electrode layer 120 is smaller than the width of the first dielectric layer 100 .
  • the width of the first electrode layer 110 can also be understood as the width in the direction of the vertical line in FIG. 16 .
  • the length of the first electrode layer 110 is the length of the horizontal line in FIG. 16 .
  • the first electrode layer 110 and the second electrode layer 120 form a transmission line to realize the parallel connection between the first external capacitors 405 in the plurality of first magnetic field enhancement components 310 .
  • the width of the first electrode layer 110 is smaller than the width of the first dielectric layer 100 , which reduces the width of the transmission line, thereby reducing the relative area between the electrode layer and the electrode layer.
  • the width of the second electrode layer 120 is smaller than the width of the first dielectric layer 100 , which reduces the width of the transmission line, thereby reducing the relative area between the electrode layer and the electrode layer.
  • the width of the transmission line becomes smaller, reducing the stray capacitance formed. Therefore, without affecting the connection of the first external capacitors 405 in the plurality of first magnetic field enhancement components 310, the stray capacitance is reduced, which is more conducive to the uniform distribution of the magnetic field and improves the quality of MRI images.
  • the first magnetic field enhancement component 310 includes a third capacitor 223 , a first inductor 241 and a first switch circuit 631 .
  • One end of the third capacitor 223 is connected to the first electrode layer 110 .
  • the other end of the third 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 used for disconnection during the radio frequency receiving stage of the MRI system.
  • the first switch circuit 631 is also configured to be turned on during the radio frequency transmission stage of the MRI system, so that parallel resonance occurs in the circuit, and the circuit is in a high-impedance state.
  • the first switch circuit 631 is used for disconnection during the radio frequency receiving stage of the MRI system.
  • the first electrode layer 110 and the second electrode layer 120 are connected through the third 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 used for conducting in the radio frequency transmission stage of the MRI system, and the third capacitor 223 is connected in parallel with the first inductor 241 to generate parallel resonance, so that the circuit is in a high resistance state.
  • the first switch circuit 631 may be controlled by a control circuit.
  • 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. During the radio frequency transmission phase of the MRI system, 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 third capacitor 223, and parallel resonance occurs, and the circuit is in a high resistance state. There is almost no current flow between the first electrode layer 110 and the second electrode layer 120 .
  • the control device In the radio frequency receiving stage of the MRI system, the control device outputs a closing command to the control terminal.
  • 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 third capacitor 223 and the second electrode layer 120 are connected in series to form a part of a resonant circuit.
  • the second cylindrical magnetic field intensifier 820 formed by the plurality of the first magnetic field enhancement components 310 restores the resonance, and greatly enhances the radio frequency receiving field of the MRI system.
  • 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 310 is applied to a magnetic resonance system to enhance the magnetic field strength of the feedback signal of the human body in the radio frequency receiving 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 310 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 310 in the receiving stage is less than 1V.
  • the seventh diode 213 and the eighth diode 214 are connected in antiparallel.
  • 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 310 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 third capacitor 223 is connected in parallel with the first inductor 241 to generate parallel resonance, so that the circuit is in a high resistance state.
  • the radio frequency emission stage there is almost no current flow between the first electrode layer 110 and the second electrode layer 120 .
  • the magnetic field generated by the first magnetic field enhancement component 310 is weakened, thereby reducing the influence of the first magnetic field enhancement component 310 on the magnetic field in the radio frequency transmission stage, thereby reducing the artifacts of the detected image and improving the clarity of the detected image.
  • 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 310 is relatively small.
  • the loaded voltage cannot reach the turn-on voltages of the seventh diode 213 and the eighth diode 214 .
  • the seventh diode 213 and the eighth diode 214 are non-conductive.
  • the first electrode layer 110 and the second electrode layer 120 are connected through the third capacitor 223, and the second cylindrical magnetic field intensifier 820 composed of a plurality of the first magnetic field intensifier components 310 is in a resonance state, play a role in enhancing the magnetic field.
  • 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 second cylindrical magnetic field intensifier 820 continuously increases during the RF receiving phase of the MRI system The strength of the magnetic field improves the stability of the feedback signal. In one embodiment, the turn-on voltage of the seventh diode 213 and the eighth diode 214 is 0.8V.
  • the seventh diode 213 and the eighth diode 214 are of the same model.
  • the voltage drop after the seventh diode 213 and the eighth diode 214 are turned on are the same, so that the increase of the magnetic field strength of the second cylindrical magnetic field enhancer 820 in the RF receiving stage In the same way, the stability of the feedback signal is further improved.
  • the first switch circuit 631 includes a fifth enhancement type MOS transistor 235 and a sixth enhancement type MOS transistor 236 .
  • the drain and the gate of the fifth 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 fifth enhancement type MOS transistor 235 is connected to the first electrode layer 110 .
  • the drain and the gate of the sixth enhancement mode MOS transistor 236 are respectively connected to the first electrode layer 110 .
  • the source of the sixth enhancement mode MOS transistor 236 is connected to one end of the first inductor 241 away from the second electrode layer 120 .
  • the fifth enhancement type MOS transistor 235 and the sixth enhancement type MOS transistor 236 are connected in anti-parallel.
  • 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 310 is relatively large.
  • the positive and negative voltages applied to both ends of the fifth enhancement type MOS transistor 235 and the sixth enhancement type MOS transistor 236 alternate.
  • the loaded voltage exceeds the channel conduction voltage of the fifth enhancement type MOS transistor 235 and the sixth enhancement type MOS transistor 236, the source and drain of the fifth enhancement type MOS transistor 235 are turned on and the sixth enhancement type MOS transistor 235 is turned on.
  • the sources and drains of the six enhancement mode MOS transistors 236 are alternately turned on.
  • the third capacitor 223 is connected in parallel with the first inductor 241 to generate parallel resonance, so that the circuit is in a high resistance state.
  • the magnetic field generated by the first magnetic field enhancement component 310 is weakened, thereby reducing the influence of the first magnetic field enhancement component 310 on the magnetic field in the radio frequency transmission stage, thereby reducing the artifacts of the detected image and improving the clarity of the detected image.
  • 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 310 is relatively small.
  • the loaded voltage cannot reach the channel turn-on voltage of the fifth enhancement type MOS transistor 235 and the sixth enhancement type MOS transistor 236, the source and drain of the fifth enhancement type MOS transistor 235 are turned on and the sixth enhancement type MOS transistor 235 is turned on.
  • the source and drain of the six enhancement mode MOS transistors 236 are non-conductive.
  • the first electrode layer 110 and the second electrode layer 120 are connected through the third capacitor 223 .
  • the second cylindrical magnetic field intensifier 820 composed of a plurality of the first magnetic field intensification components 310 is in a resonance state, and plays a role of intensifying the magnetic field.
  • the channel turn-on voltages of the fifth enhancement type MOS transistor 235 and the sixth enhancement type MOS transistor 236 are both between 0 and 1V. And the channel conduction voltage of the fifth enhancement MOS transistor 235 and the sixth enhancement MOS transistor 236 is the same, so that the second cylindrical magnetic field enhancer 820 can stably enhance the magnetic field in the RF receiving stage , the feedback signal can be output stably. In one embodiment, the channel conduction voltage of the fifth enhancement type MOS transistor 235 and the sixth enhancement type MOS transistor 236 is 0.8V.
  • the first magnetic field enhancement component 310 further includes a fourth capacitor 224 .
  • the fourth capacitor 224 is connected between the third capacitor 223 and the first electrode layer 110 .
  • the fourth capacitor 224 is connected in series with the third capacitor 223 .
  • the fourth capacitor 224 is used to reduce the partial pressure of the third capacitor 223 , improve the ability of the first magnetic field enhancement component 310 to resist strong magnetic fields, and reduce the probability of the third capacitor 223 being broken down.
  • the capacitance values of the third capacitor 223 and the fourth capacitor 224 are equal.
  • the partial voltages on the third capacitor 223 and the fourth capacitor 224 are the same, which improves the uniformity of the magnetic field, reduces the distortion caused by the inconsistent enhancement of the magnetic field, and improves the image quality.
  • an embodiment of the present application provides a second magnetic field enhancement component 320 .
  • the second magnetic field enhancement component 320 includes the first electrode layer 110 , the second electrode layer 120 and the first dielectric layer 100 .
  • 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.
  • the first structure capacitor 150 with smaller capacitance can make the second cylindrical magnetic field intensifier 820 composed of a plurality of the second magnetic field intensifier components 320 resonate.
  • the frequency is reduced to the frequency of the radio frequency coil of the magnetic resonance system, which can effectively increase the magnetic field strength.
  • the magnetic field generated by the portion of the second magnetic field enhancement component 320 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 second magnetic field enhancement component 320 is perpendicular to the first dielectric layer 100 and can generate an effective magnetic field that acts on the detection area.
  • 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 second magnetic field enhancement component 320 and other cascaded metasurfaces The degree of coupling can significantly improve the performance of the second magnetic field enhancement component 320 .
  • 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.
  • 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.
  • the materials of the first electrode layer 110 and the second electrode layer 120 may be metal materials such as gold, silver, and copper.
  • 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 parallel.
  • the first dielectric layer 100 includes opposite 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 .
  • 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 quarter of the length of the first dielectric layer 100 . 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 effect of the second magnetic field enhancement component 320 on improving the signal-to-noise ratio of the image.
  • 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 .
  • 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 form a transmission line at the non-overlapping portion of the first dielectric layer 100, and 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 may be on a straight line, so the width of the second magnetic field enhancement component 320 can be reduced, and the width of the second magnetic field enhancement component 320 can be reduced. volume.
  • the portion of the first electrode layer 110 and the second electrode layer 120 where the orthogonal projection of the first dielectric layer 100 overlaps is located in the middle 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 structure capacitor 150 in the middle of the first dielectric layer 100 can effectively improve the symmetry of the structure of the second magnetic field enhancement component 320, thereby improving the uniformity of the magnetic field.
  • the target frequency range of the second magnetic field enhancement component 320 may be 60MHz to 150MHz. In one embodiment, the target frequency range of the second magnetic field enhancement component 320 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 second magnetic field enhancement component 320 capable of generating an effective magnetic field is 230 mm. The area in which the second magnetic field enhancement component 320 can generate an effective magnetic field is significantly increased.
  • the second magnetic field enhancement component 320 further includes a first switch control circuit 430, and the first switch control circuit 430 is connected to the first electrode layer 110 and the second electrode layer 110. between the electrode layers 120 .
  • the switch control circuit 430 is configured to be turned on in the radio frequency transmitting stage of the MRI system, and turned off in the radio frequency receiving stage of the MRI system.
  • Both ends of the first switch control circuit 430 are connected between the first electrode layer 110 and the second electrode layer 120 . That is, the first switch control circuit 430 may be connected in parallel with the first structural capacitor 150 . 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 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.
  • the first switch control circuit 430 is turned on.
  • the first electrode layer 110 and the second electrode layer 120 are electrically connected.
  • the first electrode layer 110 and the second electrode layer 120 cannot form the first structure capacitor 150 . That is, the second magnetic field enhancement component 320 does not have resonance performance. Therefore, the second magnetic field enhancement component 320 cannot enhance the radio frequency transmission field.
  • the voltage difference between the first electrode layer 110 and the second electrode layer 120 is small, and the first switch control circuit 430 is turned off.
  • the first electrode layer 110 and the second electrode layer are disconnected.
  • the first electrode layer 110 and the second electrode layer 120 constitute the first structural capacitor 150 . Therefore, the second cylindrical magnetic field intensifier 820 formed by the second magnetic field intensifier assembly 320 has a resonant frequency in the radio frequency receiving stage of the MRI system.
  • the second cylindrical magnetic field enhancer 820 can enhance the radio frequency transmission field.
  • an MRI image enhancement effect diagram of the second magnetic field enhancement component 320 provided based on the conventional technology and the embodiment 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;
  • the second cylindrical magnetic field intensifier 820 composed of the second magnetic field intensifier assembly 320 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 second cylindrical magnetic field intensifier 820 constituted by a plurality of the second magnetic field intensification components 320 has better sequence universality.
  • one end of the first switch control circuit 430 is connected to the first electrode layer 110 and the second electrode layer 120 has 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 .
  • the position of the first electrode layer 110 connected to the first switch control circuit 430 corresponds to the first structure capacitor 150 . 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 constitute the first structural capacitor 150 . In this way, the influence caused by the equivalent inductance of the portion of the first electrode layer 110 that does not constitute the first structural capacitor 150 is avoided.
  • the second magnetic field enhancement component 320 further includes a first external capacitor 440 .
  • Two ends of the first external capacitor 440 are respectively connected to the first electrode layer 110 and the second electrode layer 120 .
  • the first external capacitor 440 may be an adjustable capacitor connected in parallel with the first electrode layer 110 and the second electrode layer 120 .
  • the first external capacitor 440 may be a fixed capacitor. It can be understood that the fixed capacitance or the adjustable capacitance of the first external capacitor 440 is within the protection range.
  • the first external capacitor 440 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 structure formed by the plurality of second magnetic field enhancement components 320 .
  • the resonance performance of the second cylindrical magnetic field enhancer 820 is described.
  • 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 .
  • 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.
  • the induced voltages generated by the first electrode layer 110 and the second electrode layer 120 are also alternating current voltages.
  • the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the conductance of the first diode 431 and the second diode 432 Turn on the voltage. 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.
  • the first diode 431 and the second diode 432 are in a non-conductive state.
  • the first switch control circuit 430 further 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.
  • 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 120 .
  • 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, and it can also be understood that conduction occurs only when the gate voltage is greater than its threshold voltage. channel.
  • 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 433
  • the threshold voltage at which the tube 434 is turned on Therefore, 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 a conducting state. Therefore, the first electrode layer 110 and the second electrode layer are electrically connected.
  • the first enhancement MOS transistor 433 and the second enhancement MOS transistor 434 are in a non-conducting state.
  • the second magnetic field enhancement component 320 further includes a second external capacitor 442 , the third external capacitor 443 and a second switch control circuit 450 .
  • 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 .
  • One end of the second switch control circuit 450 is connected to the first electrode layer 110 .
  • the other end of the second switch control circuit 450 is connected between the second external capacitor 442 and the third external capacitor 443 .
  • the second switch control circuit 450 is configured to be turned on in the radio frequency transmitting stage of the MRI system, and turned off in the radio frequency receiving stage of the MRI system.
  • the second external capacitor 442 and the third external capacitor 443 may be fixed capacitors or adjustable capacitors.
  • appropriate fixed capacitors can be selected as the second external capacitor 442 and the third external capacitor 443 .
  • the second external capacitor 442 and the third external capacitor 443 may be adjustable capacitors.
  • 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.
  • One end of the second switch control circuit 450 is connected to the first electrode layer 110 .
  • 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. When the voltage difference between the two ends of the first electrode layer 110 and the second electrode layer 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.
  • the second switch control circuit 450 is turned on due to the large voltage difference across the structural capacitor.
  • 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 .
  • the detuning degree of the circuit in which the second magnetic field enhancement component 320 is located can be adjusted in the radio frequency transmission stage of the MRI system.
  • the degree of detuning of the circuit in which the second magnetic field enhancement component 320 is located in the radio frequency transmission stage of the MRI system can be adjusted by the third external capacitor 443 .
  • the third external capacitor 443 is connected to the circuit, the equivalent capacitance is large, and the resonance frequency is low.
  • the resonant frequency of the second cylindrical magnetic field intensifier 820 formed by a plurality of the second magnetic field intensification components 320 can be precisely adjusted through the third external capacitor 443, so that the measured area maintains the original magnetic field strength.
  • the second cylindrical magnetic field intensifier 820 is suitable for all sequences of the magnetic resonance system.
  • the voltage difference across the structural capacitor is small, and 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 equivalent capacitance of the second external capacitor 442 and the third external capacitor 443 is small, and the resonant frequency of the loop where the second magnetic field enhancement component 320 is located is high.
  • the loop in which the second magnetic field enhancement component 320 is located can have a stable resonance frequency in the radio frequency receiving stage of the MRI system. Therefore, the resonant frequency of the loop in which the second magnetic field enhancement component 320 is located in the receiving stage reaches the operating frequency of the MRI system.
  • the second magnetic field enhancement component 320 has nonlinear response characteristics. The second magnetic field enhancement component 320 can enhance the radio frequency transmission field.
  • 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 third diode 451 is connected between the second external capacitor 442 and the third external capacitor 443 .
  • the anode of the fourth diode 452 is connected between the second external capacitor 442 and the third external capacitor 443 .
  • the cathode of the fourth diode 452 is connected to the first electrode layer 110 .
  • 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.
  • the induced voltages generated by the first electrode layer 110 and the second electrode layer 120 are also AC voltages.
  • the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the conductance of the third diode 451 and the fourth diode 452 Turn on the voltage. 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.
  • the third diode 451 and the fourth diode 452 are in a non-conductive state.
  • 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 further includes a third enhancement type MOS transistor 453 and a fourth enhancement type MOS transistor 454 .
  • the source of the third enhancement mode MOS transistor 453 is connected between the second external capacitor 442 and the third external capacitor 443 .
  • 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 .
  • the drain of the fourth enhancement mode MOS transistor 454 is connected between the second external capacitor 442 and the third external capacitor 443 .
  • the gate of the fourth enhancement mode MOS transistor 454 is connected between the second external capacitor 442 and the third external capacitor 443 . That is, 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, and it can also be understood that conduction occurs only when the gate voltage is greater than its threshold voltage. channel.
  • 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
  • the threshold voltage at which the MOS transistor 454 is turned on Therefore, 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 an on state. Therefore, the second external capacitor 442 is short-circuited.
  • the third enhancement type MOS transistor 453 and the fourth enhancement type MOS transistor 454 are in a non-conducting state.
  • 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 disconnected in the radio frequency receiving stage of the MRI system. Through the cooperation between the first structural capacitor 150 , the second external capacitor 442 and the third external capacitor 443 , it can be further improved. The effect of magnetic field enhancement.
  • 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 overlap with 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 overlap with the orthographic projection of the first dielectric layer 100 .
  • the position of the first electrode layer 110 to which the second switch control circuit 450 is connected constitutes the part of the first structural capacitor 150 . 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 first structure capacitor 150 . In this way, the influence of the equivalent inductance of the portion of the first electrode layer 110 that does not constitute the first structural capacitor 150 is avoided.
  • the second magnetic field enhancement component 320 further includes a fourth external capacitor 444 , a fifth external capacitor 445 and a third switch control circuit 460 .
  • 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 .
  • Both ends of the fourth external capacitor 444 are connected between 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, and the third switch control circuit 460 is used for radio frequency transmission in the MRI system
  • the stage is turned on, and the RF receiving stage of the MRI system is turned off.
  • the fourth external capacitor 444 and the fifth external capacitor 445 may be fixed capacitors or adjustable capacitors. When the resonant frequency of the loop where the second magnetic field enhancement component 320 is located is determined, appropriate fixed capacitors may be selected as the fourth external capacitor 444 and the fifth external capacitor 445 .
  • the fourth external capacitor 444 and the fifth external capacitor 445 may be adjustable capacitors when the resonant frequency of the loop in which the second magnetic field enhancement component 320 is located needs to be adjusted as required.
  • the second external capacitor 442 and the third external capacitor 443 may be fixed capacitors or adjustable capacitors.
  • appropriate fixed capacitors can be selected as the second external capacitor 442 and the third external capacitor 443 .
  • the second external capacitor 442 and the third external capacitor 443 may be adjustable capacitors.
  • 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.
  • 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 . 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 second magnetic field enhancement component 320 is equal, the capacitance of the fifth external capacitor 445 and the fourth external capacitor 444 in parallel is larger. Therefore, the required capacitance of the first structure capacitor 150 may be small. Therefore, the second magnetic field enhancement component 320 may have lower losses.
  • the resonant frequency of the loop where the second magnetic field enhancement component 320 is located is far away from the operating frequency of the magnetic resonance system. Therefore, by adjusting the fifth external capacitor 445 and the fourth external capacitor 444, it can be ensured that there is the second magnetic field enhancement component 320 and the second magnetic field enhancement component 320 is not present in the radio frequency transmission stage of the magnetic resonance system. the same magnetic field strength.
  • 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 .
  • 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. Only the fourth external capacitor 444 is connected in series between the first electrode layer 110 and the second electrode layer 120 . By adjusting the fourth external capacitor 444, the resonant frequency of the loop where the second magnetic field enhancement component 320 is located can be adjusted so that the resonant frequency is equal to the frequency of the radio frequency coil of the MRI system, thereby greatly enhancing the radio frequency receiving field and improving the image Signal-to-noise ratio.
  • the second cylindrical magnetic field intensifier 820 formed by the plurality of the second magnetic field intensifier components 320 can have a radio frequency receiving stage. good resonant frequency. Finally, the resonant frequency of the second cylindrical magnetic field intensifier 820 formed by a plurality of the second magnetic field intensifier assemblies 320 in the receiving stage reaches the working frequency of the magnetic resonance system.
  • the third switch control circuit 460 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 fifth diode 461 is connected to one end of the fifth external capacitor 445 .
  • the anode of the sixth diode 462 is connected to one end of the fifth external capacitor 445 .
  • the cathode of the sixth diode 462 is connected to the first electrode layer 110 .
  • 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 respectively connected in series between the first electrode layer 110 and the second electrode layer, that is, the fifth diode 461 and the Six diodes 462 are connected in reverse.
  • the induced voltages generated by the first electrode layer 110 and the second electrode layer 120 are also AC voltages.
  • the radio frequency transmission stage of the MRI system since the voltage difference between the first electrode layer 110 and the second electrode layer 120 has exceeded the conductance of the fifth diode 461 and the sixth diode 462 Turn on the voltage. Therefore, 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, 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 .
  • the fifth diode 461 and the sixth diode 462 are in a non-conductive state. Only the fourth external capacitor 444 is connected between the first electrode layer 110 and the second electrode layer 120 .
  • the third switch control circuit 460 further includes a fifth enhancement type MOS transistor 463 and a sixth enhancement type MOS transistor 464 .
  • the source of the fifth enhancement type MOS transistor 463 is connected to one end of the fifth external capacitor 445 .
  • 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 .
  • the drain of the sixth enhancement mode MOS transistor 464 is connected to one end of the fifth external capacitor 445 .
  • the gate of the sixth enhancement mode MOS transistor 464 is connected to one end of the fifth external capacitor 445 . That is, the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 are reversely connected.
  • the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 are not turned on when the gate voltage is less than the threshold voltage. It can also be understood that the conductive channel can only appear when the magnitude of the gate voltage is greater than its threshold voltage.
  • the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 Turn-on threshold voltage. Therefore, 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 in an on state. Therefore, 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 .
  • the fifth enhancement type MOS transistor 463 and the sixth enhancement type MOS transistor 464 are in a non-conducting state.
  • the fourth external capacitor 444 is connected between the first electrode layer 110 and the second electrode layer 120 .
  • one end of the third switch control circuit 460 is connected to 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 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 overlap on the orthographic projection of the first dielectric layer 100 .
  • the position of the first electrode layer 110 to which the third switch control circuit 460 is connected constitutes the part of the first structural capacitor 150 . Therefore, it can be avoided that the third switch control circuit 460 is connected to the part of the first electrode layer 110 that does not constitute the first structure capacitor 150 . In this way, the influence of the equivalent inductance of the portion of the first electrode layer 110 that does not constitute the first structural capacitor 150 is avoided.
  • the third magnetic field enhancement component 330 further includes a third electrode layer 130 disposed on the first surface 101 .
  • the second electrode layer 120 is disposed near the middle of the first dielectric layer 100 .
  • 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 .
  • the third magnetic field enhancement component 330 When the third magnetic field enhancement component 330 is located in the excitation field of the magnetic resonance system, the first electrode layer 110 and the third electrode layer 130 may function as inductances.
  • 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 to prevent 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 third magnetic field enhancement component 330 is installed on the bracket, the second surface 102 is installed close to the bracket, which can prevent the first electrode layer 110 and the third electrode layer 130 from being damaged by the bracket.
  • the length of the third electrode layer 130 is less than half of the length of the first electrolyte layer 100 . And the length of the third electrode layer 130 is greater than one third of the length of the first dielectric layer 100 . In the range from one third of the length of the first dielectric layer 100 to one half of the length of the first electrolyte layer 100 , the equivalent inductance formed by the third electrode layer 130 has a larger length. Furthermore, the third electrode layer 130 can effectively increase the area of the third magnetic field enhancement component 330 for generating an effective magnetic field.
  • 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 .
  • the widths of the third electrode layer 130 and the first electrode layer 110 may be the same.
  • 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.
  • the first dielectric layer 100 is provided with a first via hole 103 .
  • Electrode material is provided in the first via hole 103 .
  • 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, which can reduce resistance.
  • the electrode material located in the first via hole 103 is integrally formed with the first electrode and the third electrode layer 130 .
  • one end of the third electrode layer 130 close to the first electrode layer 110 coincides with the orthographic projection of the first via hole 103 .
  • One end of the second electrode layer 120 away from the first electrode layer 110 coincides with the orthographic projection of the first via hole 103 .
  • the third electrode layer 130 is in contact with the electrode material located in the first via hole 103 near the first surface 101 .
  • the second electrode layer 120 is in contact with the electrode material in the first via hole 103 close to 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 first via hole 103 .
  • 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 .
  • 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 The first structural capacitor 150 is 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.
  • 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 notch 413 and the fourth notch 414 further optimize the local magnetic field distribution and improve the detection effect of the specific position of the detection part.
  • the fourth magnetic field enhancement component 340 includes a second dielectric layer 831 , a fifth electrode layer 834 , a sixth electrode layer 833 and a seventh electrode layer 832 .
  • the second dielectric layer 831 has a third surface 805 and a fourth surface 806 disposed opposite to each other.
  • the second dielectric layer 831 has a third end 881 and a fourth end 882 disposed opposite to each other.
  • the seventh electrode layer 832 is disposed on the third surface 805 .
  • the seventh electrode layer 832 covers the third surface 805 . It can also be understood that the seventh electrode layer 832 completely covers the third surface 805 .
  • the sixth electrode layer 833 is disposed on the fourth surface 806 .
  • the sixth electrode layer 833 covers part of the fourth surface 806 .
  • the sixth electrode layer 833 is disposed close to the third end 881 .
  • the fifth electrode layer 834 and the sixth electrode layer 833 are disposed on the fourth surface 806 at intervals.
  • the fifth electrode layer 834 covers part of the fourth surface 806 .
  • the fifth electrode layer 834 is disposed close to the fourth end 882 .
  • the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 and the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 form a second structural capacitor 807 . It can also be understood that the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 overlaps with a part of the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 . In the overlapping portion, the sixth electrode layer 833 , the second dielectric layer 831 and the seventh electrode layer 832 form the second structural capacitor 807 .
  • the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 and the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 form a third structural capacitor 808 . It can also be understood that the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 overlaps with a part of the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 . In the overlapping portion, the fifth electrode layer 834 , the second dielectric layer 831 and the seventh electrode layer 832 form the third structure capacitor 808 .
  • the seventh electrode layer 832 between the second structure capacitor 807 and the third structure capacitor 808 forms a transmission line, and connects the second structure capacitor 807 and the third structure capacitor 808 in series.
  • the second structure capacitor 807 and the third structure capacitor 808 are disposed at both ends of the second dielectric layer 831 .
  • the third magnetic field enhancement component 330, the second magnetic field enhancement component 320, and the first magnetic field enhancement component 310 all have capacitors disposed in the middle.
  • the fourth magnetic field enhancement component 340 has structural capacitors disposed at both ends.
  • the inner magnetic field enhancement component 822 is the third magnetic field enhancement component 330 or the second magnetic field enhancement component 320 or the first magnetic field enhancement component 310
  • the outer magnetic field enhancement component 812 is the fourth magnetic field enhancement component
  • capacitors are formed at the two ends and the middle of the dual-core magnetic field enhancement device 30 respectively.
  • the structural capacitance of the external magnetic field enhancement component 812 in the first cylindrical magnetic field intensifier 810 is provided at both ends.
  • the capacitance of the inner magnetic field enhancement component 822 in the second cylindrical magnetic field intensifier 820 is set in the middle position.
  • the capacitance is evenly distributed in the middle and both ends.
  • the capacitance is evenly distributed in the middle and both ends, so that the electric field is mainly distributed in the middle and both ends.
  • the electric field is mainly distributed in the middle and both ends, which reduces the electrical coupling between the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 .
  • the electrical coupling between the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 is reduced, which is beneficial to realize the simultaneous enhancement of the two signal fields of the dual-core MRI. Further, the electrical coupling between the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 is reduced, which improves the magnetic field enhancement effect of the dual-core magnetic field intensifier 30 and is more beneficial to the MRI system imaging.
  • the width of the seven electrode layer 832 is smaller than the width of the seventh electrode layer 832 corresponding to the second structure capacitor 807 and the third structure capacitor 808 .
  • the seventh electrode layer 832 between the second structure capacitor 807 and the third structure capacitor 808 forms a transmission line, connecting the second structure capacitor 807 and the third structure capacitor 808 .
  • the opposite arrangement between the electrode layers corresponding to the transmission line and the electrode layers will form stray capacitances.
  • the width of the seventh electrode layer 832 between the second structure capacitor 807 and the third structure capacitor 808 is smaller than that of the seventh electrode corresponding to the second structure capacitor 807 and the third structure capacitor 808 The width of the layer 832 reduces the width of the transmission line, thereby reducing the relative area between the electrode layer and the electrode layer.
  • the width of the transmission line becomes smaller, reducing the stray capacitance formed. Therefore, without affecting the connection between the second structure capacitor 807 and the third structure capacitor 808, the stray capacitance is reduced, which is more conducive to the uniform distribution of the magnetic field and improves the quality of the MRI image.
  • the width of the first electrode layer 110 , the width of the second electrode layer 120 and the width of the seventh electrode layer 832 between the second structure capacitor 807 and the third structure capacitor 808 all change small, the relative area between the transmission line electrodes becomes small.
  • the relative area between the transmission line electrodes is reduced, reducing the resulting stray capacitance.
  • the stray capacitance is reduced, which is more conducive to the uniform distribution of the magnetic field and improves the quality of MRI images.
  • the external magnetic field enhancing component 812 and the internal magnetic field enhancing component 822 are the fourth magnetic field enhancing component 340 in this embodiment, the external magnetic field enhancing component 812 and the internal magnetic field enhancing component 822 are disposed in dislocation.
  • the outer magnetic field enhancement component 812 and the inner magnetic field enhancement component 822 are not arranged opposite to each other, but are arranged at intervals.
  • One of the inner magnetic field enhancement components 822 is disposed between the two external magnetic field enhancement components 812 . Since the width of the middle portion of the seventh electrode layer 832 is smaller than the width of the two ends, the transmission line electrodes of the external magnetic field enhancement component 812 and the transmission line electrodes of the internal magnetic field enhancement component 822 will not be disposed opposite to each other, and thus will not be formed.
  • the dual-core magnetic field enhancement device 30 does not form stray capacitance, which is beneficial to realize the simultaneous enhancement of the two signal fields of dual-core MRI, further improves the magnetic field enhancement effect, and is more conducive to MRI system imaging.
  • the fourth magnetic field enhancement element 340 includes a second dielectric layer 831 , a seventh electrode layer 832 , a sixth electrode layer 833 , a first depletion MOS transistor 231 and a second depletion MOS Tube 232.
  • the seventh electrode layer 832 is disposed on the third surface 805 .
  • the seventh electrode layer 832 is disposed close to the fourth end 882 .
  • the sixth electrode layer 833 is disposed on the third surface 805 .
  • the sixth electrode layer 833 is spaced apart from the seventh electrode layer 832 .
  • the sixth electrode layer 833 is disposed close to the third end 881 .
  • the source of the first depletion MOS transistor 231 is connected to the sixth 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 seventh 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.
  • 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.
  • the radio frequency transmitting phase and the radio frequency receiving phase there is a difference in time sequence between the radio frequency transmitting phase and the radio frequency receiving phase of several tens of milliseconds to several thousand milliseconds, which can quickly realize the connection between the first depletion-mode MOS transistor 231 and the second depletion-mode MOS transistor 232 . on and off.
  • the RF power of the RF transmitting stage and the RF receiving stage of the MRI system 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 seventh electrode layer 832 and the sixth electrode layer 833 can be controlled to be disconnected during the radio frequency emission stage. And it is connected in the RF reception 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 system. Regardless of the change, 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 sixth electrode layer 833 and the seventh electrode layer 832 are turned off. Disconnected, not connected.
  • 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 a plurality of the fourth magnetic field enhancement components 340 are formed.
  • the magnetic field enhancer is disconnected and detuned. There is no current in the fourth magnetic field enhancement component 340, and no induced magnetic field that interferes with the radio frequency is generated, thereby eliminating the influence of the magnetic field enhancer on the magnetic field in the radio frequency transmission stage.
  • the first depletion MOS transistor 231 and the second depletion MOS transistor 232 are turned on, thereby ensuring that the seventh electrode layer 832 is connected to the sixth electrode layer 833 .
  • the magnetic field intensifiers formed by the plurality of the fourth magnetic field intensification components 340 are in a connected state and can exhibit a resonance state, greatly enhancing the signal field and enhancing the image signal-to-noise ratio.
  • the seventh electrode layer 832 and the sixth electrode layer 833 are controlled to be disconnected in the radio frequency transmission stage, and the radio frequency reception Stage connection.
  • the fourth magnetic field enhancement component 340 can only enhance the radio frequency receiving field, but does not enhance the radio frequency transmitting field, thereby improving the image quality. Signal-to-noise ratio.
  • the fourth magnetic field enhancement component 340 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 fourth magnetic field enhancement components 340 form a non-linear control structure.
  • Magnetic field enhancers also have nonlinear response characteristics and can be applied to all clinical sequences including fast spin echo sequences.
  • the second dielectric layer 831 further includes a fourth surface 806 .
  • the fourth surface 806 is disposed opposite to the third surface 805 .
  • the fourth magnetic field enhancement component 340 further includes a fifth electrode layer 834 and the eighth electrode layer 835 .
  • the fifth electrode layer 834 is disposed on the fourth surface 806 .
  • the fifth electrode layer 834 covers part of the fourth surface 806 .
  • the fifth electrode layer 834 is disposed close to the fourth end 882 .
  • the eighth electrode layer 835 is disposed on the fourth surface 806 .
  • the eighth electrode layer 835 covers part of the fourth surface 806 .
  • the eighth electrode layer 835 is disposed close to the third end 881 .
  • the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 overlaps with the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 to form a third structural capacitor 808 .
  • the seventh electrode layer 832 , the second dielectric layer 831 and the fifth electrode layer 834 form the third structure capacitor 808 .
  • the orthographic projection of the eighth electrode layer 835 on the second dielectric layer 831 overlaps with the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 to form a second structural capacitor 807 .
  • the sixth electrode layer 833 , the second dielectric layer 831 and the eighth electrode layer 835 form the second structural capacitor 807 .
  • the sixth electrode layer 833 between the second structure capacitor 807 and the first depletion MOS transistor 231 may form a first transmission line.
  • the seventh electrode layer 832 between the second depletion MOS transistor 232 and the third structure capacitor 808 may form a second transmission line.
  • the second structure capacitor 807 , the first depletion MOS transistor 231 , the second depletion MOS transistor 232 and the third structure capacitor 808 are connected in series through the first transmission line and the second transmission line.
  • the fourth magnetic field enhancement component 340 will generate an induced voltage in a magnetic field environment.
  • Parasitic capacitance may be formed in the transmission line portion formed by the seventh electrode layer 832 and the sixth electrode layer 833 .
  • the parasitic capacitance is in a parallel relationship with the third structure capacitance 808 and the second structure capacitance 807 .
  • the second structure capacitor 807 and the third 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 second structure capacitance 807 and the The divided voltage of the third structure capacitor 808 .
  • the second structural capacitor 807 and the third structural 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 fourth magnetic field enhancement components 340 is reduced, so that the resonance frequency of the magnetic field enhancer formed by a plurality of the fourth magnetic field enhancement components 340 is not easily affected by the object under test, which improves the magnetic field enhancement
  • the enhanced performance of the device enhances the stability of the resonant frequency.
  • the overlapped length is related to the overlapped area.
  • Both the second structure capacitor 807 and the third structure capacitor 808 have respective facing areas. By adjusting the size of the facing area, the capacitance value of the structural capacitor formed by the sixth electrode layer 833 and the eighth electrode layer 835 can be adjusted, so that the magnetic field formed by the plurality of the fourth magnetic field enhancement components 340 can be adjusted.
  • the intensifier has the same operating frequency as the MRI system.
  • the resonant frequency of the magnetic field enhancer formed by a plurality of the fourth magnetic field enhancement components 340 is determined by the following formula Wherein, L and C are respectively the equivalent inductance and equivalent capacitance in the resonance circuit of the magnetic field enhancer formed by the plurality of the fourth magnetic field enhancement components 340 .
  • the value of the equivalent capacitance is determined by the structural capacitance Cs of each cell.
  • the relationship between the structural capacitance Cs and the area S facing the two electrode plates is: Wherein, ⁇ 0 is the vacuum permittivity, and ⁇ is the relative permittivity of the second dielectric layer 831 . d is the distance between the two electrode plates (or the thickness of the second dielectric layer 831 ).
  • the capacitance value of the structural capacitance can be adjusted, so that the magnetic field enhancer formed by the plurality of fourth magnetic field enhancement components 340 has the target resonant frequency, which can also be understood as having the same operation as the MRI system. frequency.
  • the overlapping length of the sixth electrode layer 833 and the eighth electrode layer 835 is 35 mm.
  • the overlapping length of the seventh electrode layer 832 and the fifth electrode layer 834 is 35 mm.
  • the length of the sixth electrode layer 833 between the second structure capacitor 807 and the first depletion MOS transistor 231 and the length of the third structure capacitor 808 and the second depletion MOS transistor 231 are the same. It can also be understood that, in the direction from the third end 881 to the fourth end 882 , the lengths of the first transmission line and the second transmission line are the same.
  • the first transmission line and the second transmission line may be equivalent to an inductance and a resistance.
  • An effective magnetic field is distributed between the first transmission line and the second transmission line.
  • the effective magnetic field between the third structure capacitor 808 and the second depletion MOS transistor 232 forms a first detection region.
  • the effective magnetic field between the second structural capacitor 807 and the first depletion MOS transistor 231 forms a second detection region.
  • the first detection area is the same as the second detection area.
  • the area where the effective magnetic field is formed is used as the detection area, and the detection part is detected.
  • the fourth magnetic field enhancement component 340 forms two identical detection areas on the left and right sides of the first depletion MOS transistor 231 and the second depletion MOS transistor 232 , which is more beneficial to the
  • the fourth magnetic field enhancement component 340 forms a uniform magnetic field, which improves the quality of MRI images.
  • the fifth magnetic field enhancement component 350 includes a second dielectric layer 831 , a seventh electrode layer 832 , a sixth electrode layer 833 , a fifth electrode layer 834 and an eighth electrode Layer 835.
  • the seventh electrode layer 832 is disposed on the third surface 805 .
  • the seventh electrode layer 832 is disposed close to the fourth end 882 .
  • the seventh electrode layer 832 covers part of the third surface 805 .
  • the sixth electrode layer 833 is disposed on the fourth surface 806 and covers part of the fourth surface 806 .
  • the sixth electrode layer 833 is disposed close to the third end 881 .
  • the fifth electrode layer 834 and the sixth electrode layer 833 are disposed on the fourth surface 806 at intervals.
  • the fifth electrode layer 834 covers part of the fourth surface 806 .
  • the fifth electrode layer 834 is disposed close to the fourth end 882 .
  • the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 characterizes the structural size and shape of the sixth electrode layer 833 .
  • the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 characterizes the structural size and shape of the seventh electrode layer 832 .
  • the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 and the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 partially overlap to form a fourth structural capacitor 809 .
  • the sixth electrode layer 833 and the seventh electrode layer 832 are oppositely disposed on two surfaces of the second dielectric layer 831 and have overlapping portions. At the overlapping portion, the sixth electrode layer 833 , the second dielectric layer 831 and the seventh electrode layer 832 form the fourth structural capacitor 809 .
  • the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 characterizes the structural size and shape of the fifth electrode layer 834 .
  • the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 and the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 form a third structural capacitor 808 .
  • the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 partially overlaps with the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 .
  • the fifth electrode layer 834 , the second dielectric layer 831 and the seventh electrode layer 832 form the third structural capacitor 808 .
  • the eighth electrode layer 835 and the seventh electrode layer 832 are disposed on the third surface 805 at intervals.
  • the eighth electrode layer 835 covers part of the third surface 805 .
  • the orthographic projection of the eighth electrode layer 835 on the second dielectric layer 831 characterizes the structural size and shape of the eighth electrode layer 835 .
  • the orthographic projection of the eighth electrode layer 835 on the second dielectric layer 831 is located in the projection of the sixth electrode layer 833 on the second dielectric layer 831 to form a second structural capacitor 807 . It can also be understood that the orthographic projection of the eighth electrode layer 835 on the second dielectric layer 831 and the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 partially overlap. At the overlapping portion, the eighth electrode layer 835 , the second dielectric layer 831 and the sixth electrode layer 833 form the second structural capacitor 807 .
  • the eighth electrode layer 835 and the seventh electrode layer 832 are respectively disposed on both ends of the sixth electrode layer 833 .
  • Two ends of the sixth electrode layer 833 and the eighth electrode layer 835 and the seventh electrode layer 832 respectively form the second structure capacitor 807 and the fourth structure capacitor 809 .
  • the portion between the two ends of the sixth electrode layer 833 forms a transmission line.
  • the second structural capacitor 807 and the fourth structural capacitor 809 are connected in series through a transmission line, forming a structure in which two capacitors are connected in series. Therefore, through the fifth magnetic field enhancement component 350 described in the present application, a structure in which three capacitors of the second structural capacitor 807 , the fourth structural capacitor 809 and the third structural capacitor 808 are connected in series is formed.
  • the second structure capacitor 807, the fourth structure capacitor 809 and the third structure capacitor 808 cooperate with each other, so that the enhancement device formed by the fifth magnetic field enhancement component 350 reaches the radio frequency receiving stage of the MRI system. optimum resonant frequency.
  • the enhancement device formed by the fifth magnetic field enhancement component 350 has the same operating frequency as the MRI system, it can enhance the magnetic field of the detection site and play a role in enhancing the magnetic field.
  • the second structure capacitor 807, the fourth structure capacitor 809 and the third structure capacitor 808 are connected in series, so that the second structure capacitor 807, the fourth structure capacitor 807 and the fourth structure capacitor 808 are connected in series.
  • the capacitor 809 and the third structural capacitor 808 are capacitors with larger capacitance values, which are suitable for high-frequency MRI systems.
  • the second structural capacitor 807, the fourth structural capacitor 809, and the third structural capacitor 808 use capacitors with larger capacitance values, which can avoid using small capacitors. Using a capacitor with a large capacitance value will make the resonance frequency less fluctuate, improve the stability of the resonance frequency, and be more suitable for high-field MRI systems.
  • the fifth magnetic field enhancement component 350 will generate an induced voltage in a magnetic field environment.
  • the sixth electrode layer 833 between the second structure capacitor 807 and the fourth structure capacitor 809 forms a first transmission line.
  • the seventh electrode layer 832 between the third structure capacitor 808 and the fourth structure capacitor 809 forms a second transmission line.
  • the first transmission line and the second transmission line will form parasitic capacitance.
  • the parasitic capacitance is in a parallel relationship with the second structure capacitance 807 , the fourth structure capacitance 809 and the third structure capacitance 808 , respectively.
  • the second structure capacitor 807 , the fourth structure capacitor 809 and the third structure capacitor 808 are connected in series, so that the induced voltage can be divided into multiple pieces, reducing the second structure capacitance 807 , the fourth structure capacitance The voltage division of the structural capacitor 809 and the third structural capacitor 808 .
  • the second structural capacitor 807 , the fourth structural capacitor 809 and the third structural capacitor 808 form a series structure, which reduces 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 resonant frequency will not be greatly shifted, thereby reducing the load effect of the fifth magnetic field enhancement components 350, so that the resonant frequency is reduced.
  • the resonance frequency is not easily affected by the object under test, which can improve the enhancement performance of the fifth magnetic field enhancement component 350 and enhance the stability of the resonance frequency.
  • the materials of the seventh electrode layer 832 , the sixth electrode layer 833 , the fifth electrode layer 834 and the eighth electrode layer 835 may be non-magnetic metals such as copper, silver, and gold.
  • the material of the second dielectric layer 831 may be a material with a flame-retardant material grade of FR4, a high-temperature-resistant thermoplastic resin such as polyphenylene oxide (PPE), or a Rogers 4003C material.
  • the width of the second dielectric layer 831 is 15 mm, the thickness is 0.51 mm, and the length is 250 mm.
  • the electrodes corresponding to the second structure capacitor 807 , the fourth structure capacitor 809 and the third structure capacitor 808 The overlapping length of the layers is 30 mm.
  • the length of the seventh electrode layer 832 between the fourth structural capacitor 809 and the third structural capacitor 808 and the difference between the fourth structural capacitor 809 and the second structural capacitor 807 is the same.
  • the third structural capacitor 808 and the second structural capacitor 807 are symmetrical with respect to the fourth structural capacitor 809 .
  • the effective magnetic field is distributed between the third structural capacitor 808 and the fourth structural capacitor 809 and between the second structural capacitor 807 and the fourth structural capacitor 809 .
  • the area where the effective magnetic field is formed is used as the detection area, and the detection part is detected.
  • the effective magnetic field between the third structure capacitor 808 and the fourth structure capacitor 809 forms a first detection area.
  • the effective magnetic field between the second structure capacitor 807 and the fourth structure capacitor 809 forms a second detection area.
  • the electrode layers 833 have the same length. It can be understood that the first detection area is the same as the second detection area. It can also be understood that the second structural capacitor 807 and the third structural capacitor 808 are symmetrically arranged with respect to the fourth structural capacitor 809 . It can also be understood that the second structural capacitor 807 is disposed close to the third end 881 . The third structural capacitor 808 is disposed close to the fourth end 882 . The fourth structural capacitor 809 is disposed in the middle of the connection between the third end 881 and the fourth end 882 . The second structural capacitor 807 and the third structural capacitor 808 are symmetrically arranged with respect to the fourth structural capacitor 809, forming a uniformly distributed and symmetrical magnetic field, which is beneficial to the imaging of the MRI system.
  • the width of the seventh electrode layer 832 between the fourth structure capacitor 809 and the third structure capacitor 808 is smaller than the width of the second dielectric layer 831 .
  • a transmission line is formed between the seventh electrode layer 832 between the fourth structure capacitor 809 and the third structure capacitor 808, connecting the fourth structure capacitor 809 to the third structure capacitor 808.
  • Capacitor 808 is connected. Stray capacitance is formed between the electrode layers. The width of the seventh electrode layer 832 between the fourth structure capacitor 809 and the third structure capacitor 808 becomes smaller, so that the width of the transmission line becomes smaller. The stray capacitance is reduced without affecting the connection between the fourth structure capacitor 809 and the third structure capacitor 808 .
  • the width of the sixth electrode layer 833 between the fourth structure capacitor 809 and the second structure capacitor 807 is smaller than the width of the second dielectric layer 831 .
  • the sixth electrode layer 833 between the fourth structure capacitor 809 and the second structure capacitor 807 forms a transmission line, connecting the fourth structure capacitor 809 and the second structure capacitor 807 connect. Stray capacitance is formed between the electrode layers. The width of the sixth electrode layer 833 between the fourth structure capacitor 809 and the second structure capacitor 807 becomes smaller, so that the width of the transmission line becomes smaller. The stray capacitance is reduced without affecting the connection between the fourth structure capacitor 809 and the second structure capacitor 807 .
  • the seventh electrode layer 832 between the fourth structure capacitor 809 and the third structure capacitor 808 is perpendicular to the direction from the third end 881 to the fourth end 882
  • the width is smaller than the width of the seventh electrode layer 832 corresponding to the fourth structure capacitor 809 .
  • the width of the sixth electrode layer 833 between the fourth structure capacitor 809 and the second structure capacitor 807 is smaller than the width of the seventh electrode layer 832 corresponding to the fourth structure capacitor 809 .
  • the width of the seventh electrode layer 832 corresponding to the fourth structural capacitor 809 is larger than that of the electrode layers between the structural capacitors, which is conducive to forming an effective facing area with the sixth electrode layer 833, thereby forming the The fourth structure capacitor 809 is described.
  • the width of the seventh electrode layer 832 between the fourth structure capacitor 809 and the third structure capacitor 808 is small, and the width of the seventh electrode layer 832 between the fourth structure capacitor 809 and the second structure capacitor 807 is small.
  • the width of the sixth electrode layer 833 is small, which reduces the stray capacitance without affecting the connection between the fourth structural capacitor 809 and the third structural capacitor 808 , and further improves the imaging quality of the MRI system.
  • the seventh electrode layer 832 includes a first layer 111 and a second layer 112 .
  • the first layer 111 and the second layer 112 are arranged at intervals.
  • the second layer 112 is disposed adjacent to the fourth end 882 .
  • the first layer 111 is disposed adjacent to the second layer 112 .
  • the orthographic projection of the first layer 111 on the second dielectric layer 831 partially overlaps the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 to form the fourth structural capacitor 809 .
  • the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 is located in the orthographic projection of the second layer 112 on the second dielectric layer 831 to form the third structural capacitor 808 .
  • the fifth magnetic field enhancement component 350 further includes a first depletion MOS transistor 231 and a second depletion MOS transistor 232 .
  • the source of the first depletion MOS transistor 231 is connected to one end of the first layer 111 close to the second layer 112 , and 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 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 second layer 112 .
  • the first depletion MOS transistor 231 and the second depletion MOS transistor 232 are connected in series in reverse, so that the first layer 111 and the second layer 112 can be controlled to be disconnected during the radio frequency transmission stage of the MRI system , and connected in the RF receiving stage of the MRI system.
  • 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.
  • 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.
  • the radio frequency transmitting stage and the radio frequency receiving stage 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 connection between the first depletion-mode MOS transistor 231 and the second depletion-mode MOS transistor 232 . on and off.
  • the RF power of the RF transmitting stage and the RF receiving stage of the MRI system 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, the specific value is related to the selected sequence and flip angle.
  • the first depletion MOS transistor 231 and the second depletion MOS transistor 232 are connected in series in reverse, so that the first layer 111 and the second layer 112 can be controlled to be disconnected during the radio frequency emission stage, and the RF receive stage connection.
  • 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 system. 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 first layer 111 and the second layer 112 are disconnected , not connected.
  • 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 a plurality of the fifth magnetic field enhancement components 350 are formed.
  • the magnetic field enhancer is disconnected and detuned. There is no current in the fifth magnetic field enhancement component 350, and no induced magnetic field that will interfere with the radio frequency is generated, thereby eliminating the influence of the magnetic field enhancer on the magnetic field in the radio frequency transmission stage.
  • the first depletion MOS transistor 231 and the second depletion MOS transistor 232 are turned on, thereby ensuring that the first layer 111 and the second layer 112 are connected.
  • the magnetic field intensifiers formed by the plurality of the fifth magnetic field intensification components 350 are in a connected state and can exhibit a resonance state, greatly enhancing the signal field and enhancing the image signal-to-noise ratio.
  • the first layer 111 and the second layer 112 are controlled by the first depletion MOS transistor 231 and the second depletion MOS transistor 232 to be disconnected during the radio frequency transmission stage of the MRI system, and the radio frequency Receive phase connection.
  • the fifth magnetic field enhancement component 350 can only enhance the radio frequency receiving field, but does not enhance the radio frequency transmitting field, which improves the Image signal-to-noise ratio.
  • the fifth magnetic field enhancement component 350 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 fifth magnetic field enhancement components 350 form a non-linear control structure.
  • Magnetic field enhancers also have nonlinear response characteristics and can be applied to all clinical sequences including fast spin echo sequences.
  • the fifth magnetic field enhancement component 350 further includes a third diode 451 , a fourth diode 452 , a second external capacitor 442 and a third external capacitor 443 .
  • the anode of the third diode 451 is electrically connected to the seventh electrode layer 832 corresponding to the third structure capacitor 808 .
  • the cathode of the fourth diode 452 is electrically connected to the seventh electrode layer 832 corresponding to the third structure capacitor 808 .
  • One end of the third external capacitor 443 is electrically connected to the fifth electrode layer 834 .
  • the other end of the third external capacitor 443 is electrically 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 , respectively.
  • the other end of the second external capacitor 442 is electrically connected to the seventh electrode layer 832 corresponding to the third structure capacitor 808 .
  • 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 of an MRI system is between a few volts and hundreds of volts. In the radio frequency receiving stage, the voltage across the structural capacitor is at the level of millivolts.
  • the turn-on voltages of the third diode 451 and the fourth diode 452 may be greater than 1 volt. That is, when the voltage difference between the seventh electrode layer 832 and the fifth electrode layer 834 is greater than 1 volt, the third diode 451 or the fourth diode 452 is turned on. When the voltage difference between the seventh electrode layer 832 and the fifth electrode layer 834 is less than 1 volt, the third diode 451 and the fourth diode 452 are disconnected.
  • 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 connected in series between the seventh electrode layer 832 and the fifth electrode layer 834, respectively. The third diode 451 and the fourth diode 452 are reversely connected.
  • the induced voltages generated by the seventh electrode layer 832 and the fifth electrode layer 834 are also alternating current voltages.
  • the voltage difference between the seventh electrode layer 832 and the fifth electrode layer 834 has exceeded the turn-on voltage of the third diode 451 and the fourth diode 452 . Therefore, no matter which of the seventh electrode layer 832 and the fifth electrode layer 834 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. Only the third external capacitor 443 is connected between the seventh electrode layer 832 and the fifth electrode layer 834 . By adjusting the capacitance value of the third external capacitor 443 , the degree of detuning of the loop in which the fifth magnetic field enhancement component 350 is located can be reduced or avoided in the radio frequency transmission stage.
  • the magnetic field strength of the measured area in the magnetic resonance system can be the same.
  • the first cylindrical magnetic field intensifier 810 or the second cylindrical magnetic field intensifier 820 adopts the fifth magnetic field intensifier assembly 350 the influence of the magnetic field intensifier on the radio frequency transmission stage can be eliminated, so that the magnetic field intensifier can be applied Improves the clinical utility of magnetic field enhancers for all clinical sequences.
  • the third diode 451 and the fourth diode 452 are in a non-conductive state.
  • the second external capacitor 442 and the third external capacitor 443 are connected in series between the seventh electrode layer 832 and the fifth electrode layer 834 .
  • the fifth magnetic field enhancement component 350 further includes a first inductor 241 , a third diode 213 and a fourth diode 214 .
  • One end of the third capacitor 223 is connected to one end of the first layer 111 close to the second layer 112 .
  • the other end of the third capacitor 223 is connected to the end of the second layer 112 away from the fourth end 882 .
  • One end of the first inductor 241 is connected to one end of the first layer 111 close to the second layer 112 .
  • the other ends of the first inductor 241 are respectively connected to the cathode of the third diode 213 and the anode of the fourth diode 214 .
  • the anode of the third diode 213 and the cathode of the fourth diode 214 are connected to one end of the second layer 112 away from the fourth end 882 .
  • the magnetic field energy in the transmitting stage is more than 1000 times the magnetic field energy in the receiving stage.
  • the induced voltage in the launch phase is between tens of volts and hundreds of volts.
  • the induced voltage in the receiving stage is less than 1V.
  • the third diode 213 and the fourth diode 214 are connected in antiparallel.
  • 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 fifth magnetic field enhancement component 350 is relatively large.
  • the positive and negative voltages applied across the third diode 213 and the fourth diode 214 alternate. When the loaded voltage exceeds the turn-on voltages of the third diode 213 and the fourth diode 214, the third diode 213 and the fourth diode 214 are turned on.
  • the third capacitor 223 is connected in parallel with the first inductor 241 to generate parallel resonance, so that the circuit formed by the first inductor 241 , the third diode 213 , the fourth diode 214 and the third capacitor 223 is at a high level. blocking state.
  • the magnetic field generated by the fifth magnetic field enhancement component 350 is weakened, thereby reducing the influence of the fifth magnetic field enhancement component 350 on the magnetic field in the radio frequency transmitting stage, thereby reducing the artifacts of the detected image and improving the definition of the detected image.
  • the detection part transmits a feedback signal, and the field strength of the magnetic field is small.
  • the induced voltage generated by the fifth magnetic field enhancing component 350 is relatively small.
  • the loaded voltage cannot reach the turn-on voltages of the third diode 213 and the fourth diode 214, and the third diode 213 and the fourth diode 214 are not conducting.
  • the third structural capacitor 808 and the fourth structural capacitor 809 are connected through the third capacitor 223, and current flows therethrough.
  • the magnetic field enhancer composed of a plurality of the fifth magnetic field enhancement components 350 is in a resonance state and plays a role of enhancing the magnetic field.
  • the sixth magnetic field enhancement component 360 includes a second dielectric layer 831 , a seventh electrode layer 832 , a sixth electrode layer 833 , a fifth electrode layer 834 , and an eighth electrode layer 835 , the first electrode connection layer 123 , and the ninth electrode layer 836 .
  • a second via hole 220 is provided in the middle of the second dielectric layer 831 .
  • the seventh electrode layer 832 is disposed on the third surface 805 .
  • the seventh electrode layer 832 covers part of the third surface 805 .
  • the seventh electrode layer 832 is disposed close to the fourth end 882 .
  • the sixth electrode layer 833 is disposed on the fourth surface 806 .
  • the sixth electrode layer 833 covers part of the fourth surface 806 .
  • the sixth electrode layer 833 is disposed near the middle of the second dielectric layer 831 .
  • the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 partially overlaps the orthographic projection of the sixth electrode layer 833 on the second dielectric layer 831 to form a fourth structural capacitor 809 .
  • the fourth structure capacitor 809 is disposed near the middle of the second dielectric layer 831 .
  • the fifth electrode layer 834 is disposed on the fourth surface 806 .
  • the fifth electrode layer 834 covers part of the fourth surface 806 .
  • the fifth electrode layer 834 is disposed close to the fourth end 882 .
  • the fifth electrode layer 834 is spaced apart from the sixth electrode layer 833 .
  • the orthographic projection of the fifth electrode layer 834 on the second dielectric layer 831 is located in the orthographic projection of the seventh electrode layer 832 on the second dielectric layer 831 to form a third structural capacitor 808 .
  • the eighth electrode layer 835 is disposed on the third surface 805 .
  • the eighth electrode layer 835 covers part of the third surface 805 .
  • the eighth electrode layer 835 is disposed close to the third end 881 .
  • the eighth electrode layer 835 is spaced apart from the seventh electrode layer 832 .
  • the first electrode connection layer 123 is disposed on the second via hole 220 .
  • the first electrode connection layer 123 extends to the third surface 805 and the fourth surface 806, respectively.
  • Two ends of the first electrode connection layer 123 are respectively connected to the sixth electrode layer 833 and the eighth electrode layer 835 .
  • the ninth electrode layer 836 and the sixth electrode layer 833 are disposed on the fourth surface 806 at intervals.
  • the ninth electrode layer 836 covers a portion of the fourth surface 806 .
  • the ninth electrode layer 836 is disposed close to the third end 881 .
  • the orthographic projection of the ninth electrode layer 836 on the second dielectric layer 831 is located in the orthographic projection of the eighth electrode layer 835 on the second dielectric layer 831 to form a second structural capacitor 807 .
  • the orthographic projection of the ninth electrode layer 836 on the second dielectric layer 831 characterizes the structural size and shape of the ninth electrode layer 836 .
  • the orthographic projection of the ninth electrode layer 836 on the second dielectric layer 831 overlaps with a part of the orthographic projection of the eighth electrode layer 835 on the second dielectric layer 831 .
  • the ninth electrode layer 836 , the second dielectric layer 831 and the eighth electrode layer 835 form the second structural capacitor 807 .
  • the eighth electrode layer 835 and the first electrode connection layer 123 between the second structure capacitor 807 and the fourth structure capacitor 809 form a transmission line.
  • the second structure capacitor 807 and the fourth structure capacitor 809 are connected in series through a transmission line.
  • the seventh electrode layer 832 between the fourth structure capacitor 809 and the third structure capacitor 808 forms a transmission line.
  • the fourth structure capacitor 809 and the third structure capacitor 808 are connected in series through a transmission line.
  • the sixth electrode layer 833 and the eighth electrode layer 835 on different surfaces are connected through the second via hole 220 and the first electrode connection layer 123, so that the second structure capacitor 807 is connected to the first electrode layer 835.
  • Four-structure capacitors 809 are connected in series.
  • the ninth electrode layer 836 and the fifth electrode layer 834 may be connected on the same side.
  • a gap is formed between the eighth electrode layer 835 and the seventh electrode layer 832 , and the third surface 805 is exposed.
  • Two ends of the first electrode connection layer 123 extend to the third surface 805 and the fourth surface 806 respectively, and connect the sixth electrode layer 833 on different surfaces to the eighth electrode layer 835 .
  • the transmission line formed by the eighth electrode layer 835 and the first electrode connecting layer 123 between the fourth structure capacitor 809 and the second structure capacitor 807 supplements the space corresponding to the gap, so that The space corresponding to the gap also has a magnetic field formed.
  • the space corresponding to the gap is formed by a magnetic field, and there is no situation where a certain part does not have a magnetic field.
  • Two ends of the first electrode connection layer 123 extend to the third surface 805 and the fourth surface 806 respectively.
  • the first electrode connection layer 123 connects the sixth electrode layer 833 and the eighth electrode layer 835 on different surfaces, so that the magnetic field distribution is more uniform, and the imaging quality of the MRI system is improved.
  • the second via hole 220 is disposed near the middle of the second dielectric layer 831 . And the diameter of the second via hole 220 is smaller than the width of the second dielectric layer 831 .
  • the first electrode connection layer 123 is respectively connected to the eighth electrode layer 835 and the sixth electrode layer 833 through the second via hole 220 .
  • the sixth electrode layer 833 is disposed opposite to the seventh electrode layer 832 to form the fourth structure capacitor 809 .
  • the second via hole 220 is disposed close to the middle of the second dielectric layer 831 , so that the fourth structural capacitor 809 is also disposed close to the middle of the second dielectric layer 831 , which improves the uniformity and symmetry of the magnetic field.
  • the diameter of the second via hole 220 is smaller than the width of the second dielectric layer 831 of the second dielectric layer 831 , which reduces the area of the first electrode connection layer 123 in the second via hole 220 , thereby reducing all The stray capacitance formed by the first electrode connection layer 123 is described.
  • the eighth electrode layer 835 , the first electrode connection layer 123 and the sixth electrode layer 833 are integrally formed.
  • the sixth magnetic field enhancement component 360 further includes a first external capacitor 440 , a first diode 431 and a second diode 432 .
  • Two ends of the first external capacitor 440 are electrically connected to the seventh electrode layer 832 and the fifth electrode layer 834 respectively.
  • the anode of the first diode 431 is electrically connected to the seventh electrode layer 832 .
  • the cathode of the first diode 431 is electrically connected to the fifth electrode layer 834 .
  • the cathode of the second diode 432 is electrically connected to the seventh electrode layer 832 .
  • the anode of the second diode 432 is electrically connected to the fifth electrode layer 834 .
  • 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 connected in parallel between the seventh electrode layer 832 and the fifth electrode layer 834 . The first diode 431 and the second diode 432 are connected in reverse.
  • the induced voltages generated by the seventh electrode layer 832 and the sixth electrode layer 833 are also AC voltages.
  • the voltage difference between the seventh electrode layer 832 and the fifth electrode layer 834 has exceeded the conductance of the first diode 431 and the second diode 432 Turn on the voltage. Therefore, no matter which of the seventh electrode layer 832 and the fifth electrode layer 834 has a higher voltage, one of the first diode 431 and the second diode 432 is always turned on. Therefore, the seventh electrode layer 832 and the fifth electrode layer 834 are electrically connected.
  • the third structural capacitor 808 is shorted.
  • the magnetic field enhancer formed by the sixth magnetic field enhancement component 360 is in a detuned state.
  • the first diode 431 and the second diode 432 are in a non-conductive state.
  • the magnetic field enhancer formed by the sixth magnetic field enhancing component 360 is in a resonance state.
  • the element capacitance in the foregoing embodiment may be a fixed capacitance or an adjustable capacitance.
  • the element capacitance can be selected as a fixed capacitance, so that the fixed capacitance cooperates with other structural capacitances and element capacitances, so that the resonant frequency of the circuit where the magnetic field enhancement component is located is equal to the frequency of the radio frequency coil of the MRI system , thereby enhancing the magnetic field.
  • the element capacitance can be adjusted. By adjusting the adjustable capacitance, the resonant frequency is adjusted, so that the magnetic field enhancement component is suitable for different working environments.
  • the diameter of the second cylindrical magnetic field enhancer 820 is 100 mm.
  • the second cylindrical magnetic field enhancer 820 includes a plurality of the first magnetic field enhancement components 310 or the second magnetic field enhancement components 320 or the third magnetic field enhancement components 330 .
  • the width of the transmission line between the first electrode layer 110 and the second electrode layer 120 is 4 mm.
  • the width of the first dielectric layer 100 is 15 mm.
  • the first capacitor 405 is set in the middle position, and the capacitance value is 40pF.
  • the length of the first dielectric layer 100 is 250 mm.
  • the material of the first dielectric layer 100 is selected from Rogers 4003C, and the thickness is 0.51 mm.
  • the resonant frequency of the second cylindrical magnetic field intensifier 820 is 52 MHz, which corresponds to the operating frequency of the nuclear magnetic resonance imaging system when the main magnetic field strength is 3T.
  • the second cylindrical magnetic field enhancer 820 is used to enhance the nuclear magnetic signal of the 31 P non-hydrogen proton nucleus.
  • the diameter of the first cylindrical magnetic field enhancer 810 is 120 mm.
  • the first cylindrical magnetic field enhancer 810 includes a plurality of the fourth magnetic field enhancement components 340 .
  • the transmission line width of the seventh electrode layer 832 between the second structure capacitor 807 and the third structure capacitor 808 is 4 mm.
  • the width of the second dielectric layer 831 is 15 mm.
  • the second structure capacitor 807 and the third structure capacitor 808 are located at both ends of the fourth magnetic field enhancement component 340 .
  • the length of the overlapping portion of the electrodes corresponding to the second structural capacitor 807 and the third structural capacitor 808 is 15 mm or 14.8 mm.
  • the material of the second dielectric layer 831 is selected from Rogers 4003C, and the thickness is 0.51 mm.
  • the length of the second dielectric layer 831 is 250 mm.
  • the resonant frequency of the first cylindrical magnetic field intensifier 810 is 128 MHz, which corresponds to the operating frequency of the nuclear magnetic resonance imaging system when the main magnetic field strength is 3T.
  • the first cylindrical magnetic field enhancer 810 is used to enhance the nuclear magnetic signal of the hydrogen proton nucleus of 1 H.
  • the dual-core magnetic field intensifier 30 described in the present application adopts the second cylindrical magnetic field intensifier 820 and the first cylindrical magnetic field intensifier 810 in the above-mentioned embodiment, and has two resonance peaks, and the resonance frequencies are respectively 51.6MHz and 128.8MHz. Therefore, the dual-nucleus magnetic field enhancement device 30 can simultaneously enhance the signal fields of 31 P and 1 H, can detect different target nuclei in the same part, and can display MRI imaging information corresponding to different target nuclei in the detection part.
  • the present application provides a magnetic resonance system, including the dual-nuclear magnetic field enhancement device 30 described in any of the foregoing embodiments.

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Abstract

一种双核磁场增强装置(30),包括第一筒形磁场增强器(810)与第二筒形磁场增强器(820);第一筒形磁场增强器(810)包围形成第一容纳空间(819),第一筒形磁场增强器(810)用于增强检测部位的氢质子核的核磁信号;第二筒形磁场增强器(820)设置于第一容纳空间(819)内,第二筒形磁场增强器(820)包围形成第二容纳空间(829),检测部位可以收纳于所述第二容纳空间(829)内,第二筒形磁场增强器(820)用于增强检测部位的非氢质子核的核磁信号,第一容纳空间(819)大于第二容纳空间(829);检测部位收纳于第二容纳空间(829)内时,也同时收纳于第一容纳空间(819)内。双核磁场增强装置(30)实现了对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。相对传统技术,双核磁场增强装置(30)具有更高的磁场增强效果。在应用于MRI***成像时,双核磁场增强装置(30)可以辅助MRI***获得更高质量的图像。

Description

一种双核MRI的图像增强超构表面器件
相关申请
本申请要求2021年02月10日申请的,申请号为202110183943.2,名称为“一种双核MRI的图像增强超构表面器件”和2021年02月10日申请的,申请号为202110183916.5,名称为“一种基于相位调控超构表面的双核MRI的图像增强超构表面器件”的中国专利申请的优先权,在此将其全文引入作为参考。
技术领域
本申请涉及磁共振成像技术领域,特别是涉及一种应用于MRI***的双核磁场增强装置及磁共振***。
背景技术
核磁共振成像技术(Magnetic Resonance Imaging,MRI)为非介入探测方式,是医药、生物、神经科学领域的一项重要的基础诊断技术。目前传统MRI***传输的信号强度主要来自于氢质子 1H。在具有核磁信号的所有原子核中,氢质子 1H在人体内含量最高,并且氢质子 1H的旋磁比也最高,具有最强的核磁共振信号。但是,基于氢质子 1H的MRI包含的代谢、离子交换等生物学信息较少,而 23Na、 31P、 19F等非质子核可以提供丰富的生物学信息。因此,基于 23Na、 31P、 19F等非质子核的成像在医学及生命科学研究中具有重要的研究意义。
在进行 23Na、 31P、 19F等非质子核的MRI时,提高非质子核图像的信噪比,具有重要意义。信噪比主要决定于静磁场强度。但是,静磁场强度的增加会带来如下三个问题:1)射频(RF)场非均匀性增大,调谐难度增加;2)人体组织产热增加,带来安全隐患,患者还容易出现眩晕和呕吐等不良反应:3)购置成本大幅度增加,对大多数小规模医院来说是一种负担。因此,如何采用尽量小的静磁场强度同时能够获得高的成像质量成为MRI技术中一个至关重要的问题。
超构材料的出现为MRI成像质量和效率的提高,提供了一种新颖的更有效的方法。超构材料具有许多天然材料所不具备的特殊性质。通过电磁波与超构材料的金属或电介质基元间的相互作用及基元间的耦合效应,可以实现对电磁波传播路径与电磁场场强分布的控制。工作原理是利用超构材料形成的结构中的电磁谐振,实现呈各向异性和梯度分布等电磁参数的调节。并且,通过对超构材料的几何尺寸、形状和介电常数等参数的设计,能够实现对不同频点的谐振增强。
然而,传统的磁场增强器件都是针对氢原子核 1H等单核MRI设计的,没有针对非质子核和质子核的双核结构的设计,导致无法获得代谢、离子交换等丰富的生物学信息。
申请内容
有鉴于此,本申请提供一种双核磁场增强装置及磁共振***。
本申请提供一种双核磁场增强装置。所述双核磁场增强装置包括第一筒形磁场增强器与第二 筒形磁场增强器。所述第一筒形磁场增强器包围形成第一容纳空间。所述第一筒形磁场增强器用于增强检测部位的氢质子核的核磁信号。所述第二筒形磁场增强器设置于所述第一容纳空间内,用于增强所述检测部位的非氢质子核的核磁信号。所述第二筒形磁场增强器包围形成第二容纳空间,用于容纳检测部位。
上述双核磁场增强装置及磁共振***,所述第一筒形磁场增强器与所述第二筒形磁场增强器用于检测相同部位的不同目标核,可以显示出所述检测部位的不同目标核对应的MRI成像信息。所述第二筒形磁场增强器设置于所述第一容纳空间内。所述第二筒形磁场增强器设置于所述双核磁场增强装置的内部。所述第一筒形磁场增强器设置于所述双核磁场增强装置的外侧。所述第二筒形磁场增强器与所述第一筒形磁场增强器嵌套设置。所述双核磁场增强装置可以增强所述检测部位中的氢质子核的核磁信号和非氢质子核的核磁信号。所述双核磁场增强装置实现了对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。相对传统技术,所述双核磁场增强装置可以具有更高的磁场增强效果。在应用于MRI***成像时,所述双核磁场增强装置可以辅助MRI***获得更高质量的图像。
附图说明
为了更清楚地说明本申请实施例或现有技术中的技术方案,下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍,显而易见地,下面描述中的附图仅仅是本申请的实施例,对于本领域普通技术人员来讲,在不付出创造性劳动的前提下,还可以根据提供的附图获得其他的附图。
图1为本申请提供的双核磁场增强装置中第一筒形磁场增强器和第二筒形磁场增强器的结构示意图。图2为本申请提供的双核磁场增强装置的整体结构示意图。图3为本申请提供的第一筒形支架的结构示意图。图4为本申请提供的第二筒形支架的结构示意图。图5为本申请提供的第一谐振控制电路与外磁场增强组件的连接示意图。图6为本申请提供的第二谐振控制电路与内磁场增强组件的连接示意图。图7为本申请提供的一个实施例中第一筒形支架、第一环形导电片以及第二环形导电片的***结构示意图。图8为本申请提供的图51所示的第一环形导电片、第二环形导电片以及第一相位调控缺口的侧视图。图9为本申请一个实施例提供的感应场与调控缺口的垂直关系图。图10为本申请一个实施例提供的谐振效果示意图。图11为本申请一个实施例提供的第一筒形磁场增强器的内部磁场分布图。图12为本申请提供的一个实施例中第二筒形支架、第三环形导电片以及第四环形导电片的***结构示意图。图13为本申请提供的第三相位调控缺口与第一相位调控缺口的位置关系示意图。图14为本申请提供的一个实施例中双核磁场增强装置的谐振频率示意图。图15为本申请提供的一个实施例中第一磁场增强组件的侧视图。图16为图15中第一磁场增强组件的俯视图。图17为本申请一个实施例提供的第一磁场增强组件侧视图。图18为本申请一个实施例提供的第一磁场增强组件侧视图。图19为本申请一个实施例提供的第一磁场增强组件侧视图。图20为本申请一个实施例提供的第二磁场增强组件侧视图。 图21为本申请一个实施例提供的第二磁场增强组件俯视图。图22为本申请一个实施例提供的第二磁场增强组件仰视图。图23为本申请一个实施例提供的第二磁场增强组件结构图。图24为本申请一个实施例提供的第二磁场增强组件在射频发射阶段和射频接收阶段频率对比图。图25为本申请一个实施例提供的第二磁场增强组件效果对比图。图26为本申请另一个实施例提供的第二磁场增强组件结构图。图27为本申请另一个实施例提供的第二磁场增强组件结构图。图28为本申请另一个实施例提供的第二磁场增强组件结构图。图29为本申请另一个实施例提供的第二磁场增强组件结构图。图30为本申请一个实施例提供的第二磁场增强组件在射频发射阶段和射频接收阶段频率对比图。图31为本申请另一个实施例提供的第二磁场增强组件结构图。图32为本申请另一个实施例提供的第二磁场增强组件结构图。图33为本申请另一个实施例提供的第二磁场增强组件结构图。图34为本申请一个实施例提供的第二磁场增强组件在射频发射阶段和射频接收阶段频率对比图。图35为本申请另一个实施例提供的第二磁场增强组件结构图。图36为本申请另一个实施例提供的第二磁场增强组件结构图。图37为本申请另一个实施例提供的第三磁场增强组件侧视图。图38为本申请一个实施例提供的第三磁场增强组件俯视图。图39为本申请一个实施例提供的第三磁场增强组件仰视图。图40为本申请一个实施例提供的第一电极层和所述第二电极层在所述第一电介质层的正投影示意图。图41为本申请另一个实施例提供的第一电极层和所述第二电极层在所述第一电介质层的正投影形状示意图。图42为本申请一个实施例中提供的第四磁场增强组件的侧视图。图43为本申请图35中实施例的俯视图。图44为本申请提供的一个实施例中第四磁场增强组件的侧视图。图45为本申请提供的图44实施例中第四磁场增强组件的***结构示意图。图46为本申请提供的图44实施例中第四磁场增强组件的俯视图。图47为本申请提供的一个实施例中第五磁场增强组件的侧视图。图48为本申请提供的图37实施例中第五磁场增强组件的结构示意图。图49为本申请提供的一个实施例中第五磁场增强组件的俯视图。图50为本申请提供的一个实施例中第五磁场增强组件的仰视图。图51为本申请提供的一个实施例中第五磁场增强组件的侧视图。图52为本申请提供的一个实施例中第五磁场增强组件的侧视图。图53为本申请提供的一个实施例中第五磁场增强组件的侧视图。图54为本申请提供的一个实施例中第二过孔的俯视图。图55为本申请提供的一个实施例中第六磁场增强组件的侧视图。图56为本申请提供的一个实施例中第六磁场增强组件的侧视图。图57为本申请提供的一个实施例中双核磁场增强装置的谐振频率示意图。
具体实施方式
下面将结合本申请实施例中的附图,对本申请实施例中的技术方案进行清楚、完整地描述,显然,所描述的实施例仅仅是本申请一部分实施例,而不是全部的实施例。基于本申请中的实施例,本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例,都属于本申请保护的范围。
为了使本申请的目的、技术方案及优点更加清楚明白,以下通过实施例,并结合附图,对本 申请进行进一步详细说明。应当理解,此处所描述的具体实施例仅用以解释本申请,并不用于限定本申请。
请参见图1,本申请提供双核磁场增强装置30。所述双核磁场增强装置30包括第一筒形磁场增强器810与第二筒形磁场增强器820。所述第一筒形磁场增强器810包围形成第一容纳空间819。所述第一筒形磁场增强器810用于增强检测部位的氢质子核的核磁信号。所述第二筒形磁场增强器820设置于所述第一容纳空间819内。所述第二筒形磁场增强器820包围形成第二容纳空间829。所述检测部位可以收纳于所述第二容纳空间829内。所述第二筒形磁场增强器820用于增强所述检测部位的非氢质子核的核磁信号。所述第一容纳空间819大于所述第二容纳空间829。所述检测部位收纳于所述第二容纳空间829内时,也同时收纳于所述第一容纳空间819内。也可以理解为,所述第一容纳空间819将所述第二容纳空间829包围。所述第二容纳空间829将所述检测部位包围。所述检测部位同时位于所述第一容纳空间819和所述第二容纳空间829内。
本实施例中,所述检测部位可以为人或者动物的手臂、腿、腹部等。所述检测部位包括了氢质子核和氢质子核以外的非氢质子核。非氢质子核包括 23Na、 31P、 19F等。非氢质子核可以提供代谢、离子交换等丰富的生物学信息。所述第一筒形磁场增强器810的直径大于所述第二筒形磁场增强器820的直径。所述第一筒形磁场增强器810嵌套在所述第二筒形磁场增强器820的外侧。所述第一筒形磁场增强器810与所述第二筒形磁场增强器820用于检测相同部位的不同目标核,可以显示出所述检测部位的不同目标核对应的MRI成像信息。
所述第二筒形磁场增强器820设置于所述第一容纳空间819内。所述第二筒形磁场增强器820设置于所述双核磁场增强装置30的内部。所述第一筒形磁场增强器810设置于所述双核磁场增强装置30的外侧。所述第二筒形磁场增强器820与所述第一筒形磁场增强器810嵌套设置。所述双核磁场增强装置30可以增强所述检测部位中的氢质子核的核磁信号和非氢质子核的核磁信号。所述双核磁场增强装置30实现了对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。相对传统技术,所述双核磁场增强装置30可以具有更高的磁场增强效果。在应用于MRI***成像时,所述双核磁场增强装置30可以辅助MRI***获得更高质量的图像。
所述双核磁场增强装置30为双核MRI的图像增强超构表面器件。所述双核MRI的图像增强超构表面器件可以增强所述检测部位中的氢质子核的核磁信号和非氢质子核的核磁信号。所述双核MRI的图像增强超构表面器件实现了对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。
所述第一筒形磁场增强器810与所述第二筒形磁场增强器820的直径和长度可以根据所述检测部位来决定。在一个实施例中,所述第一筒形磁场增强器810长度为350mm。所述第一筒形磁场增强器810的直径为120mm。所述第二筒形磁场增强器820的直径为100mm。所述第二筒形磁场增强器820的长度为450mm。
请参见图2和图3,在一个实施例中,所述第一筒形磁场增强器810包括第一筒形支架811与多个外磁场增强组件812。所述第一筒形支架811具有第一外表面801与第一内表面802。所述第一外表面801环绕所述第一内表面802。所述第一外表面801与所述第一内表面802间隔相对设置。所述第一内表面802包围形成所述第一容纳空间819。
所述外磁场增强组件812的延伸方向与所述第一筒形支架811的第一中心轴线的延伸方向相同。所述外磁场增强组件812环绕所述第一筒形支架811的第一中心轴线间隔设置于所述第一外表面801。每个所述外磁场增强组件812具有相对设置的第一端和第二端。所述多个外磁场增强组件812的第一端依次连接。所述多个外磁场增强组件812的第一端沿环绕所述第一中心轴线的方向逐个电连接。所述多个外磁场增强组件812的第二端依次连接。所述多个外磁场增强组件812的第二端沿着环绕所述第一筒形支架811的所述第一中心轴线的方向逐个电连接。当应用于MRI***中时,所述第一筒形磁场增强器810的谐振频率与工作频率相同时,可以增强所述检测部位的氢质子核的核磁信号,有利于MRI***成像。
在一个实施例中,所述第一筒形磁场增强器810还包括第一环形导电片861、第二环形导电片862以及第一固定结构883。所述第一环形导电片861和所述第二环形导电片862分别设置于所述第一筒形支架811相对的两端。所述第一筒形支架811沿第一中心轴线方向,具有相对设置的第一端与第二端。所述第一筒形支架811的第一端至第二端的方向,和所述第一筒形支架811的第一中心轴线的方向相同。所述第一环形导电片861设置于所述第一筒形支架811的第一端。所述第二环形导电片862设置于所述第一筒形支架811的第二端。
所述第一环形导电片861环绕所述第一筒形支架811的第一中心轴线设置。也可以理解为,第一中心轴线经过所述第一环形导电片861的几何中心点。所述第二环形导电片862环绕所述第一筒形支架811的第一中心轴线设置。也可以理解为,第一中心轴线经过所述第二环形导电片862的几何中心点。
在一个实施例中,每个所述外磁场增强组件812可以为条状结构,沿第二中心轴线方向延伸。每个所述外磁场增强组件812的两端分别与所述第一环形导电片861和所述第二环形导电片862连接。也可以理解为,每个所述外磁场增强组件812具有相对设置的第一端和第二端。所述内磁场增强组件822的第一端至第二端的方向和所述第二中心轴线方向相同。
所述多个外磁场增强组件812的第一端通过所述第一环形导电片861依次连接。所述多个外磁场增强组件812的第二端通过所述第二环形导电片862依次连接。所述多个外磁场增强组件812通过所述第一筒形支架811、所述第一环形导电片861以及所述第二环形导电片862进行连接固定。
在一个实施例中,所述第一环形导电片861为闭合圆环。所述第一环形导电片861将所述多个外磁场增强组件812的第一端依次连接起来,形成闭合结构。所述第二环形导电片862为闭合圆环。所述第二环形导电片862将所述多个外磁场增强组件812的第二端依次连接起来,形成闭 合结构。
在一个实施例中,所述第一筒形磁场增强器810还包括多个第一固定结构883。所述多个第一固定结构883环绕所述第一筒形支架811的第一中心轴线间隔设置。所述多个第一固定结构883设置于所述第一外表面801。且所述多个第一固定结构883间隔设置于所述第一筒形支架811的两端。每一个所述外磁场增强组件812分别对应所述第一筒形支架811的第一端的所述第一固定结构883和所述第一筒形支架811的第二端的所述第一固定结构883。通过所述第一筒形支架811的两端的所述第一固定结构883,固定一个所述外磁场增强组件812。进而,将所述外磁场增强组件812固定于所述第一筒形支架811的所述第一外表面801。
在一个实施例中,所述多个第一固定结构883可以为通槽。所述通槽可以用于***所述外磁场增强组件812。每两个所述第一固定结构883分别固定一个所述外磁场增强组件812的两端。通过所述第一固定结构883可以将所述外磁场增强组件812固定于所述第一筒形支架811的所述第一外表面801。
在一个实施例中,所述第一环形导电片861以及所述第二环形导电片862可以为金、银、铜等金属材料制成。
在一个实施例中,所述外磁场增强组件812的长度可以为150mm至400mm。在一个实施例中,所述外磁场增强组件812的长度为250mm。
请参见图4,在一个实施例中,所述第一筒形支架811具有第一内表面802。所述第一内表面802包围形成所述第一容纳空间819。所述第一内表面802与所述第一外表面801间隔相对。所述第一外表面801环绕所述第一内表面802设置。所述第二筒形磁场增强器820包括第二筒形支架821与多个内磁场增强组件822。所述第二筒形支架821设置于所述第一容纳空间819内。所述第二筒形支架821具有第二外表面803与第二内表面804。所述第二外表面803与所述第一内表面802间隔相对设置。所述多个内磁场增强组件822等间隔设置于所述第二外表面803。所述多个内磁场增强组件822设置于所述第二外表面803与所述第一内表面802之间。所述内磁场增强组件822的延伸方向与所述第二筒形支架821的第二中心轴线的延伸方向相同。所述第二筒形支架821的第一端至所述第二筒形支架821的第二端的方向,和第二中心轴线方向相同。每个所述内磁场增强组件822具有相对设置的第一端和第二端,所述多个内磁场增强组件822的第一端依次连接。所述多个内磁场增强组件822的第二端依次连接。
所述第二内表面804包围形成一个第二容纳空间829。所述第二容纳空间829用于放置所述检测部位,例如手臂、腿、腹部等。
所述多个内磁场增强组件822的第一端沿环绕所述第二中心轴线的方向逐个电连接。所述多个内磁场增强组件822的第二端沿环绕所述第二中心轴线的方向逐个电连接。
所述多个内磁场增强组件822通过第一端和第二端连接,形成了一个谐振回路,具有其特定的谐振频率。当应用于MRI***中时,所述多个内磁场增强组件822形成的谐振回路的谐振频 率与工作频率相同时,可以增强所述检测部位的非氢质子核的核磁信号,有利于MRI***成像。
在一个实施例中,所述第二筒形磁场增强器820还包括第三环形导电片866、第四环形导电片867以及第二固定结构884。所述第三环形导电片866与所述第四环形导电片867分别设置于所述第二筒形支架821相对的两端。所述第二筒形支架821沿第二中心轴线方向,具有相对设置的第一端与第二端。所述第三环形导电片866设置于所述第二筒形支架821的第一端。所述第四环形导电片867设置于所述第二筒形支架821的第二端。
所述第三环形导电片866环绕所述第二筒形支架821的第二中心轴线设置。也可以理解为,第二中心轴线经过所述第三环形导电片866的几何中心点。所述第四环形导电片867环绕所述第二筒形支架821的第二中心轴线设置。也可以理解为,第二中心轴线经过所述第四环形导电片867的几何中心点。
在一个实施例中,每个所述内磁场增强组件822可以为条状结构,沿第二中心轴线方向延伸。每个所述内磁场增强组件822的两端分别与所述第三环形导电片866和所述第四环形导电片867连接。也可以理解为,每个所述内磁场增强组件822具有相对设置的第一端和第二端。所述多个内磁场增强组件822的第一端通过所述第三环形导电片866依次连接。所述多个内磁场增强组件822的第二端通过所述第四环形导电片867依次连接。所述多个内磁场增强组件822通过所述第二筒形支架821、所述第三环形导电片866和所述第四环形导电片867进行连接固定。
在一个实施例中,所述第三环形导电片866为闭合圆环。所述第三环形导电片866将所述多个内磁场增强组件822的第一端依次连接起来,形成闭合结构。所述第四环形导电片867为闭合圆环。所述第四环形导电片867将所述多个内磁场增强组件822的第二端依次连接起来,形成闭合结构。
在一个实施例中,所述第二筒形磁场增强器820还包括多个第二固定结构884。所述多个第二固定结构884环绕所述第二筒形支架821的第二中心轴线间隔设置于所述第二外表面803。且所述多个第二固定结构884间隔设置于间隔设置于两端。每一个所述内磁场增强组件821分别对应所述第二筒形支架821的第一端的所述第二固定结构884和所述第二筒形支架821的第二端的所述第二固定结构884。通过所述第二筒形支架821的两端的所述第二固定结构884,固定一个所述内磁场增强组件822。进而,将所述内磁场增强组件82固定于所述第二筒形支架821的所述第二外表面803。
在一个实施例中,所述多个第二固定结构884可以为通槽。所述通槽可以用于***所述内磁场增强组件822。每两个所述第二固定结构884分别固定一个所述内磁场增强组件822的两端。通过所述第二固定结构884可以将所述内磁场增强组件822固定于所述第二筒形支架821的所述第二外表面803。
请参见图5,在一个实施例中,所述双核磁场增强装置30还包括多个第一谐振控制电路851。一个所述第一谐振控制电路851与一个所述外磁场增强组件812电连接,用于控制所述外磁场增 强组件812的工作状态。
本实施例中,所述外磁场增强组件812的工作状态包括失谐状态以及谐振状态。失谐状态是指在MRI***的射频发射阶段,所述第一谐振控制电路851控制所述外磁场增强组件812所在的谐振回路不发生谐振,呈现失谐状态。谐振状态是指在MRI***的射频接收阶段,所述第一谐振控制电路851通过调控自身的电容、电感等电子元件,使得所述外磁场增强组件812所在的谐振回路处于谐振状态。此时,谐振回路的谐振频率与工作频率相同,可以增强所述检测部位的氢质子核的核磁信号,有利于MRI***成像。
在一个实施例中,图5为示意连接图。所述第一谐振控制电路851与所述外磁场增强组件812的连接位置可根据下述实施例中任一实施例中所述的电路结构进行变化。所述第一谐振控制电路851包括下述实施例中任一实施例中所述的电路结构,用来调控谐振状态。
请参见图6,在一个实施例中,所述双核磁场增强装置30还包括多个第二谐振控制电路852。一个所述第二谐振控制电路852与一个所述内磁场增强组件822电连接,用于控制所述内磁场增强组件822的工作状态。
本实施例中,所述内磁场增强组件822的工作状态包括失谐状态以及谐振状态。失谐状态是指在MRI***的射频发射阶段,所述第二谐振控制电路852所在的谐振回路不发生谐振,呈现失谐状态。谐振状态是指在MRI***的射频接收阶段,所述第二谐振控制电路852通过调控自身的电容、电感等电子元件,使得所述外磁场增强组件812形成的谐振回路处于谐振状态。此时,谐振回路的谐振频率与工作频率相同,可以增强所述检测部位的非氢质子核的核磁信号,有利于MRI***成像。
在一个实施例中,图6为示意连接图。所述第二谐振控制电路852与所述内磁场增强组件822的连接位置可根据下述实施例中任一实施例中所述的电路结构进行变化。所述第二谐振控制电路852包括下述实施例中任一实施例中所述的电路结构,用来调控谐振状态。
在一个实施例中,所述第一筒形磁场增强器810的第一中心轴线与所述第二筒形磁场增强器820的第二中心轴线重合。所述第一筒形磁场增强器810与所述第二筒形磁场增强器820共中心轴,有利于在所述检测部位周围形成对称均匀的磁场。
所述第一筒形磁场增强器810的中截面与所述第二筒形磁场增强器820的中截面重合。所述第一筒形磁场增强器810的中截面是指所述第一筒形磁场增强器810的中间位置处,垂直于中心轴线方向的横截面。所述第二筒形磁场增强器820的中截面是指所述第二筒形磁场增强器820的中间位置处,垂直于中心轴线方向的横截面。
沿着中心轴线方向,所述第一筒形磁场增强器810的长度小于所述第二筒形磁场增强器820的长度。并且,所述第一筒形磁场增强器810的两端与所述第二筒形磁场增强器820的两端不共面。也可以理解为,所述第一筒形磁场增强器810的第一端与所述第二筒形磁场增强器820的第一端错位设置。所述第一筒形磁场增强器810的第二端与所述第二筒形磁场增强器820的第二端 错位设置。所述第一筒形磁场增强器810和所述第二筒形磁场增强器820具有不同的长度,且两端不共面。进而,所述第一筒形磁场增强器810和所述第二筒形磁场增强器820的端环错开。所述第一筒形磁场增强器810和所述第二筒形磁场增强器820的端环错开,避免了在端口位置处形成杂散电容,减小所述第一筒形磁场增强器810和所述第二筒形磁场增强器820之间的耦合效应。
在一个实施例中,在同一侧,所述第一筒形磁场增强器810的第一端与所述第二筒形磁场增强器820的第一端至少相差20mm。所述第一筒形磁场增强器810的第二端与所述第二筒形磁场增强器820的第二端至少相差20mm。在MRI***的射频接收阶段时,所述第一筒形磁场增强器810和所述第二筒形磁场增强器820的两端至少相差20mm的错位设置,减少了杂散电容。进而,所述第一筒形磁场增强器810和所述第二筒形磁场增强器820的错位设置减小了两者之间的耦合效应,使得所述第一筒形磁场增强器810和所述第二筒形磁场增强器820的的频率更加稳定,更有利于MRI***图像增强。
请参见图7与图8,在一个实施例中,所述第一环形导电片861环绕所述第一筒形支架811的第一中心轴线设置。所述第一环形导电片861的两端的连接处具有第一相位调控缺口871。所述第一环形导电片861环绕所述第一筒形支架811的第一中心轴线形成环状结构时,在首尾靠近处形成所述第一相位调控缺口871。所述第一相位调控缺口871使得所述第一环形导电片861的首尾不连接。
所述第二环形导电片862环绕所述第一筒形支架811的第一中心轴线设置。所述第二环形导电片862的两端的连接处具有第二相位调控缺口872。所述第二环形导电片862环绕所述第一筒形支架811的第一中心轴线形成环状结构时,在首尾靠近处形成所述第二相位调控缺口872。所述第二相位调控缺口872使得所述第二环形导电片862的首尾不连接。
请参见图9,所述第一筒形磁场增强器810放在磁共振***中的激发场中时,所述第一筒形磁场增强器810产生的感应场的方向总是垂直于所述第一筒形支架811的第一中心轴线、所述第一相位调控缺口871以及所述第二相位调控缺口872形成的平面。通过调整所述第一相位调控缺口871以及所述第二相位调控缺口872的位置控制感应场的相位,达到对所述检测部位精确检测的目的。所述第一筒形磁场增强器810设置有所述第一相位调控缺口871与所述第二相位调控缺口872,仍然具有良好的谐振性能,能够增强信号场,提高图像质量。
请参见图10,所述第一筒形磁场增强器810中的所述第一环形导电片861以及所述第二环形导电片862具有开口(也可以理解为开环结构)与所述第一环形导电片861以及所述第二环形导电片862为闭合结构相比,所述第一筒形磁场增强器810的谐振性能并没有明显区别。所述第一环形导电片861以及所述第二环形导电片862具有开口,并没有影响所述第一筒形磁场增强器810的谐振性能。
请参见图11,所述第一筒形磁场增强器810的内部磁场区域的ROI(Region of interest)区域仍然高度均匀,不会引起图像对比度的改变。
本申请所述双核磁场增强装置30的所述第二筒形磁场增强器820与所述第一筒形磁场增强器810嵌套设置,提高了所述双核磁场增强装置30的磁场增强效果,更有利于MRI***成像。所述双核磁场增强装置30能够实现对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。并且,在所述第二筒形磁场增强器820增强所述检测部位的非氢质子核的核磁信号的同时,可以通过所述第一筒形磁场增强器810控制感应场的相位。进而,所述第一筒形磁场增强器810控制感应场的相位,能够达到对所述检测部位精确检测的目的,更有利于MRI***成像。
所述双核磁场增强装置30为基于相位调控超构表面的双核MRI的图像增强超构表面器件。所述基于相位调控超构表面的双核MRI的图像增强超构表面器件可以实现对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。所述基于相位调控超构表面的双核MRI的图像增强超构表面器件可以对非氢质子核的感应场的相位进行调控。
在一个实施例中,所述第一筒形磁场增强器810放入磁共振***后,用于增强局部区域磁场强度,提高磁共振检测效果。所述多个外磁场增强组件812可以等间隔设置于所述第一外表面801。所述多个外磁场增强组件812等间隔设置,可以提高局部磁场的均匀性。
在一个实施例中,所述第一相位调控缺口871与所述第二相位调控缺口872相对设置。且所述第一相位调控缺口871与所述第二相位调控缺口872的连线与所述第一筒形支架811的第一中心轴线平行。
本实施例中,所述第一相位调控缺口871、所述第二相位调控缺口872以及所述第一筒形支架811的中心轴线形成一个平面。当所述第一筒形磁场增强器810放在磁共振***中的激发场中时,所述第一筒形磁场增强器810产生的感应场的方向总是垂直于所述第一筒形支架811的第一中心轴线、所述第一相位调控缺口871以及所述第二相位调控缺口872形成的平面。由于所述第一相位调控缺口871、所述第二相位调控缺口872以及所述第一筒形支架811的第一中心轴线共面,通过调整所述第一相位调控缺口871以及所述第二相位调控缺口872的位置控制感应场的相位,达到对所述检测部位精确检测的目的。
并且,所述第二筒形磁场增强器820与所述第一筒形磁场增强器810嵌套设置。所述第一相位调控缺口871、所述第二相位调控缺口872以及所述第一筒形支架811的中心轴线共面,不会对所述第二筒形磁场增强器820增强的非氢质子核的核磁信号产生影响。从而,更有利于实现对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。
在一个实施例中,所述多个外磁场增强组件812设置于所述第一相位调控缺口871和所述第二相位调控缺口872的连线的两侧。
本实施例中,所述所述第一相位调控缺口871和所述第二相位调控缺口872的连线与所述第一筒形支架811的第一中心轴线平行。所述多个外磁场增强组件812关于所述所述第一相位调控缺口871和所述第二相位调控缺口872的连线对称设置。所述第一相位调控缺口871与所述第二相位调控缺口872设置于相邻两个所述外磁场增强组件812之间。设置有所述第一相位调控缺口 871的所述第一环形导电片861的首尾端向两个相邻的所述外磁场增强组件812之间的间隙伸出。设置有所述第二相位调控缺口872的所述第二环形导电片862首尾端向两个相邻的所述外磁场增强组件812之间的间隙伸出。
所述第一相位调控缺口871和所述第二相位调控缺口872并未设置在所述外磁场增强组件812上,进而不会对所述外磁场增强组件812造成影响,使得所述多个外磁场增强组件812增强的磁场更加稳定均匀。
所述第一相位调控缺口871与所述第二相位调控缺口872破坏了所述第一筒形磁场增强器810的各向同性性质,使得所述第一筒形磁场增强器810增强后的磁场具有特定相位。通过控制所述第一相位调控缺口871与所述第二相位调控缺口872的位置来控制相位。
在一个实施例中,所述第一相位调控缺口871和所述第二相位调控缺口872关于所述第一筒形磁场增强器810的中截面对称设置。所述第一筒形磁场增强器810的中截面是指所述第一筒形磁场增强器810的中间位置处,垂直于中心轴线方向的横截面。所述第一筒形磁场增强器810产生的感应场的方向总是平行于所述第一筒形磁场增强器810的中截面。所述第一相位调控缺口871和所述第二相位调控缺口872关于所述第一筒形磁场增强器810的中截面对称,使得所述第一筒形磁场增强器810产生的感应场的方向相对于所述第一筒形磁场增强器810的中截面的平行度更高。
请参见图12与图13,在一个实施例中,所述第三环形导电片866环绕所述第二筒形支架821的第二中心轴线设置。第二中心轴线经过所述第三环形导电片866的几何中心点。所述第三环形导电片866的两端的连接处具有第三相位调控缺口873。所述第三环形导电片866环绕所述第二筒形支架821的第二中心轴线形成环状结构时,在首尾靠近处形成第三相位调控缺口873。所述第三相位调控缺口873使得所述第三环形导电片866的首尾不连接。
所述第四环形导电片867环绕所述第二筒形支架821的第二中心轴线设置。第二中心轴线经过所述第四环形导电片867的几何中心点。所述第四环形导电片867的两端的连接处具有第四相位调控缺口874。所述第四环形导电片867环绕所述第二筒形支架821的第二中心轴线形成环状结构时,在首尾靠近处形成第四相位调控缺口874。所述第四相位调控缺口874使得所述第四环形导电片867的首尾不连接。
所述第二筒形磁场增强器820放在磁共振***中的激发场中时,所述第二筒形磁场增强器820产生的感应场的方向总是垂直于所述第二筒形支架821的第二中心轴线、所述第三相位调控缺口873以及所述第四相位调控缺口874形成的平面。通过调整所述第三相位调控缺口873与所述第四相位调控缺口874的位置控制感应场的相位,达到对所述检测部位精确检测的目的。所述第二筒形磁场增强器820设置有所述第三相位调控缺口873与所述第四相位调控缺口874,仍然具有良好的谐振性能,能够增强信号场,提高图像质量。
所述第二筒形磁场增强器820的内部磁场区域的ROI(Region of interest)区域仍然高度均 匀,不会引起图像对比度的改变。
因此,本申请所述双核磁场增强装置30,能够实现对对氢质子核和非氢质子核的双核MRI两个信号场的同时增强。并且,通过所述第一筒形磁场增强器810和所述第二筒形磁场增强器820能够调节其对应感应场的相位,达到对所述检测部位精确检测的目的,更有利于MRI***成像。
在一个实施例中,所述第三相位调控缺口873与所述第四相位调控缺口874相对设置。所述第三相位调控缺口873与所述第四相位调控缺口874的连线与所述第二筒形支架821的第二中心轴线平行。
本实施例中,所述第三相位调控缺口873、所述第四相位调控缺口874以及所述第二筒形支架821的第二中心轴线形成一个平面。当所述第二筒形磁场增强器820放在磁共振***中的激发场中时,所述第二筒形磁场增强器820产生的感应场的方向总是垂直于所述第二筒形支架821的第二中心轴线、所述第三相位调控缺口873以及所述第四相位调控缺口874形成的平面。由于所述第二筒形支架821的第二中心轴线、所述第三相位调控缺口873以及所述第四相位调控缺口874共面,通过调整所述第三相位调控缺口873以及所述第四相位调控缺口874的位置控制感应场的相位,达到对所述检测部位精确检测的目的。
并且,所述第二筒形磁场增强器820与所述第一筒形磁场增强器810嵌套设置。所述第二筒形支架821的中心轴线、所述第三相位调控缺口873以及所述第四相位调控缺口874共面不会对所述第一筒形磁场增强器810增强的氢质子核的核磁信号产生影响,更有利于实现对双核MRI两个信号场的同时增强。
在一个实施例中,所述多个内磁场增强组件822设置于所述第三相位调控缺口873与所述第四相位调控缺口874的连线的两侧。
本实施例中,所述第三相位调控缺口873与所述第四相位调控缺口874的连线与所述第二筒形支架821的第二中心轴线平行。所述多个内磁场增强组件822关于所述第三相位调控缺口873与所述第四相位调控缺口874的连线对称设置。所述第三相位调控缺口873与所述第四相位调控缺口874设置于相邻两个所述内磁场增强组件822之间。设置有所述第三相位调控缺口873的所述第三环形导电片866的首尾端向两个相邻的所述内磁场增强组件822之间的间隙伸出。设置有所述第四相位调控缺口874的所述第四环形导电片867的首尾端向两个相邻的所述内磁场增强组件822之间的间隙伸出。
所述第三相位调控缺口873与所述第四相位调控缺口874并未设置在所述内磁场增强组件822上,进而不会对所述内磁场增强组件822造成影响,使得所述第二筒形磁场增强器820增强的磁场稳定均匀。
所述第三相位调控缺口873与所述第四相位调控缺口874破坏了所述第二筒形磁场增强器820的各向同性性质,使得所述第二筒形磁场增强器820增强后的磁场具有特定相位。通过控制 所述第三相位调控缺口873与所述第四相位调控缺口874的位置来控制相位。
请参见图13,在一个实施例中,所述第三相位调控缺口873与所述第一相位调控缺口871正交设置。所述第三相位调控缺口873与所述第一相位调控缺口871投影至中截面时,所述第三相位调控缺口873与所述第一相位调控缺口871之间的夹角为90°。所述第三相位调控缺口873与所述第一相位调控缺口871位于同一平面时,所述第三相位调控缺口873与所述第一相位调控缺口871之间的夹角为90°。所述第四相位调控缺口874与所述第二相位调控缺口872正交设置。所述第四相位调控缺口874与所述第二相位调控缺口872投影至中截面时,所述第四相位调控缺口874与所述第二相位调控缺口872之间的夹角为90°。所述第四相位调控缺口874与所述第二相位调控缺口872位于同一平面时,所述第四相位调控缺口874与所述第二相位调控缺口872之间的夹角为90°。
所述第二筒形磁场增强器820与所述第一筒形磁场增强器810嵌套设置。且所述第二筒形磁场增强器820与所述第一筒形磁场增强器810具有正交设置的相位调控缺口,使得所述第二筒形磁场增强器820与所述第一筒形磁场增强器810产生的感应磁场相位也正交。所述第二筒形磁场增强器820与所述第一筒形磁场增强器810产生的感应磁场相位正交,使得所述第二筒形磁场增强器820与所述第一筒形磁场增强器810的耦合效应达到最小。因此,本申请所述双核磁场增强装置30,能够实现对双核MRI两个信号场的同时增强。所述第二筒形磁场增强器820与所述第一筒形磁场增强器810产生的感应磁场相位正交,减小了耦合效应,更有利于MRI***成像。
在一个实施例中,围绕所述第一筒形支架811的第一中心轴线的方向,所述第一相位调控缺口871与所述第二相位调控缺口872的弧长相等。所述第一相位调控缺口871与所述第二相位调控缺口872的弧长,等于相邻两个所述外磁场增强组件812之间的间隔距离。围绕所述第二筒形支架821的第二中心轴线的方向,所述第三相位调控缺口873与所述第四相位调控缺口874的弧长相等。所述第三相位调控缺口873与所述第四相位调控缺口874的弧长,等于相邻两个所述所述内磁场增强组件822之间的间隔距离。
本实施例中,所述第一相位调控缺口871与所述第二相位调控缺口872没有设置在所述外磁场增强组件812上,进而不会对所述外磁场增强组件812造成影响,使得所述第一筒形磁场增强器810增强的磁场稳定均匀。所述第三相位调控缺口873与所述第四相位调控缺口874并未设置在所述内磁场增强组件822上,进而不会对所述内磁场增强组件822造成影响,使得所述第二筒形磁场增强器820增强的磁场稳定均匀。
所述第一相位调控缺口871与所述第二相位调控缺口872的弧长,等于相邻两个所述外磁场增强组件812之间的距离。所述第一环形导电片861和所述第二环形导电片862不会有多余部分的延伸,进而减小了杂散电容,降低了所述第一筒形磁场增强器810和所述第二筒形磁场增强器820之间的耦合效应。
所述第三相位调控缺口873与所述第四相位调控缺口874的弧长,等于相邻两个所述所述内 磁场增强组件822之间的距离。所述第三环形导电片866和所述第四环形导电片867不会有多余部分的延伸,进而减小了杂散电容,降低了所述第一筒形磁场增强器810和所述第二筒形磁场增强器820之间的耦合效应。
在一个实施例中,所述第一筒形磁场增强器810和所述第二筒形磁场增强器820同轴线对称放置。所述第一筒形磁场增强器810中的所述第一环形导电片861与所述第二环形导电片862分别设置有所述第一相位调控缺口871与所述第二相位调控缺口872。所述第二筒形磁场增强器820的所述第三环形导电片866与所述第四环形导电片867为闭合环状结构,没有设置相位调控缺口。
请参见图14,在一个实施例中,本申请所述双核磁场增强装置30,具有两个谐振峰,谐振频率分别为63.2MHz和128.2MHz。因此,所述双核磁场增强装置30能够同时增强 31P和 1H的信号场,可以检测相同部位的不同目标核,可以显示出所述检测部位的不同目标核对应的MRI成像信息,提高二者的图像质量。
在一个实施例中,所述内磁场增强组件822可以为下述实施例中第一磁场增强组件310、第二磁场增强组件320、第三磁场增强组件330、第四磁场增强组件340、第五磁场增强组件350以及第六磁场增强组件360中任意一个场增强组件。所述外磁场增强组件812可以为下述实施例中第一磁场增强组件310、第二磁场增强组件320、第三磁场增强组件330、第四磁场增强组件340、第五磁场增强组件350以及第六磁场增强组件360中任意一个场增强组件。
请参见图15,在一个实施例中,所述第一磁场增强组件310包括第一电介质层100、第一电极层110、第二电极层120以及第一外接电容405。所述第一电介质层100包括相对间隔设置的第一表面101和第二表面102。所述第一电介质层100具有相对设置的第一端103与第二端104。所述第一电极层110设置于所述第一表面101。所述第一电极层110覆盖部分所述第一表面101。所述第一电极层110靠近所述第二端104设置。所述第二电极层120设置于所述第一表面101。所述第二电极层120与所述第一电极层110间隔设置。所述第二电极层120覆盖部分所述第一表面101。所述第二电极层120靠近所述第一端103设置。所述第一外接电容405的一端与所述第二电极层120远离所述第一端103的一端连接。所述第一外接电容405的另一端与所述第一电极层110远离所述第二端104的一端连接。且所述第一外接电容405靠近所述第一电介质层100的中部设置。
所述第一外接电容405可以为固定电容,也可以为可调电容。当MRI***的射频线圈的频率确定后,可以选择合适的固定电容,使得所述第二筒形磁场增强器820的谐振频率与MRI***的射频线圈的频率相等,进而起到增强磁场的作用。当所述第二筒形磁场增强器820的使用环境不确定,例如MRI***的射频线圈的频率不确定时,所述第一外接电容405可以采用可调电容。通过调节可调电容可以调节所述第二筒形磁场增强器820的谐振频率,以使所述第二筒形磁场增强器820适用不同的环境。
在一个实施例中,所述第一外接电容405的一端与所述第一电极层110靠近所述第二电极层120的一端连接。所述第一外接电容405的另一端与所述第二电极层120靠近所述第一电极层110的一端连接。所述第一外接电容405与所述第一电极层110和所述第二电极层120的连接位置靠近所述第一电极层110和所述第二电极层120之间的间隙。上述结构中,所述第一外接电容405与所述第一电极层110和所述第二电极层120之间连接的导线相对较短。本实施例中,所述第一外接电容405的连接方式可以使得所述第一电极层110和所述第二电极层120之间的电阻较小,从而降低所述第一磁场增强组件310的能耗。
请参见图16,在一个实施例中,沿环绕所述第二筒形支架821的第二中心轴线的方向,所述第一电极层110的宽度小于所述第一电介质层100的宽度。所述第二电极层120的宽度小于所述第一电介质层100的宽度。
本实施例中,所述第一电极层110的宽度也可以理解为图16中垂线方向的宽度。所述第一电极层110的长度为图16中水平线方向的长度。所述第一电极层110与所述第二电极层120形成传输线,实现所述多个第一磁场增强组件310中所述第一外接电容405之间的并联连接。所述第一电极层110的宽度小于所述第一电介质层100的宽度,会使得传输线的宽度变小,进而使得电极层与电极层之间的相对面积变小。所述第二电极层120的宽度小于所述第一电介质层100的宽度,会使得传输线的宽度变小,进而使得电极层与电极层之间的相对面积变小。
因此,传输线的宽度变小,减小了形成的杂散电容。所以,在不影响所述多个第一磁场增强组件310中所述第一外接电容405连接的情况下,减小了杂散电容,更有利于磁场均匀分布,提高了MRI图像质量。
请参见图17,在一个实施例中,所述第一磁场增强组件310包括第三电容223、第一电感241和第一开关电路631。所述第三电容223的一端与所述第一电极层110连接。所述第三电容223的另一端与所述第二电极层120连接。所述第一电感241的一端与所述第二电极层120连接。所述第一开关电路631连接于所述第一电感241的另一端与所述第一电极层110之间。所述第一开关电路631用于在MRI***的射频接收阶段时断开。所述第一开关电路631还用于在MRI***的射频发送阶段时导通,以使所在电路发生并联谐振,处于高阻状态。
所述第一开关电路631用于在MRI***的射频接收阶段时断开。所述第一电极层110和所述第二电极层120通过所述第三电容223连接。所述第一开关电路631和所述第一电感241不参与电路导通。所述第一开关电路631还用于在MRI***的射频发射阶段时导通,所述第三电容223与所述第一电感241并联,发生并联谐振,使得所在电路处于高阻状态。
所述第一开关电路631可以是通过控制电路控制。在一个实施例中,所述第一开关电路631包括开关元件和控制端。所述开关元件的一端与所述第一电感241远离所述第二电极层120的一端连接。所述开关元件的另一端与所述第一电极层110连接。控制端与外部的控制装置连接。所述控制端用于接收闭合和断开命令。在MRI***的射频发射阶段,所述控制装置向所述控制端 输出闭合命令。当所述控制端接收到闭合命令时,所述第一电感241与所述第一电极层110导通。所述第一电感241与所述第三电容223并联连接,发生并联谐振,所在电路处于高阻状态。所述第一电极层110与所述第二电极层120之间几乎没有电流流通。
在MRI***的射频接收阶段,所述控制装置向所述控制端输出闭合命令。当所述控制端接收到断开命令时,所述第一电感241与所述第一电极层110断开。所述第一电极层110、所述第三电容223与所述第二电极层120串联连接,构成谐振电路的一部分。多个所述第一磁场增强组件310构成的第二筒形磁场增强器820恢复谐振,大幅度增强MRI***的射频接收场。
在一个实施例中,所述第一开关电路631包括第七二极管213和第八二极管214。所述第七二极管213的正极与所述第一电极层110连接。所述第七二极管213的负极与所述第一电感241的另一端连接。所述第八二极管214的正极与所述第一电感241的另一端连接,所述第八二极管214的负极与所述第一电极层110连接。
所述第一磁场增强组件310应用于磁共振***,以在MRI***的射频接收阶段增强人体反馈信号的磁场强度。在磁共振***的射频发射阶段,发射阶段的磁场能量是接收阶段的磁场能量的1000倍以上。发射阶段的所述第一磁场增强组件310的感应电压在几十伏到几百伏之间。接收阶段的所述第一磁场增强组件310的感应电压小于1V。
所述第七二极管213和所述第八二极管214反向并联连接。在MRI***的射频发射阶段,射频线圈发射射频发射信号,磁场的场强较大。所述第一磁场增强组件310产生的感应电压较大。加载在所述第七二极管213和所述第八二极管214两端的电压正反交替。加载的电压超过所述第七二极管213和所述第八二极管214的开启电压,所述第七二极管213和所述第八二极管214导通。所述第三电容223与所述第一电感241并联,发生并联谐振,使得所在电路处于高阻状态。射频发射阶段,所述第一电极层110和所述第二电极层120之间几乎没有电流流通。所述第一磁场增强组件310产生的磁场减弱,进而减小所述第一磁场增强组件310对射频发射阶段磁场的影响,从而减小检测图像的伪影,提高检测图像的清晰度。
在MRI***的射频接收阶段,检测部位发射反馈信号,磁场的场强较小。所述第一磁场增强组件310产生的感应电压较小。加载的电压不能达到所述第七二极管213和所述第八二极管214的开启电压。所述第七二极管213和所述第八二极管214不导通。所述第一电极层110和所述第二电极层120通过所述第三电容223连接,多个所述第一磁场增强组件310组成的所述第二筒形磁场增强器820处于谐振状态,起到增强磁场的作用。
在一个实施例中,所述第七二极管213和所述第八二极管214的开启电压均在0至1V之间。在一个实施例中,所述第七二极管213和所述第八二极管214的开启电压相同,以使在所述第二筒形磁场增强器820在MRI***的射频接收阶段连续增加磁场强度,提高反馈信号的稳定性。在一个实施例中,所述第七二极管213和所述第八二极管214的开启电压为0.8V。
在一个实施例中,所述第七二极管213和所述第八二极管214的型号相同。所述第七二极管 213和所述第八二极管214导通后的压降相同,以使在所述所述第二筒形磁场增强器820在射频接收阶段磁场强度的增大幅度相同,进一步提高反馈信号的稳定性。
请参见图18,在一个实施例中,所述第一开关电路631包括第五增强型MOS管235和第六增强型MOS管236。所述第五增强型MOS管235的漏极和栅极分别与所述第一电感241远离所述第二电极层120的一端连接。所述第五增强型MOS管235的源极与所述第一电极层110连接。所述第六增强型MOS管236的漏极和栅极分别所述第一电极层110连接。所述第六增强型MOS管236的源极与所述第一电感241远离所述第二电极层120的一端连接。
所述第五增强型MOS管235和所述第六增强型MOS管236反向并联连接。在MRI***的射频发射阶段,射频线圈发射射频发射信号,磁场的场强较大。所述第一磁场增强组件310产生的感应电压较大。加载在所述第五增强型MOS管235和所述第六增强型MOS管236两端的电压正反交替。加载的电压超过所述第五增强型MOS管235和所述第六增强型MOS管236的沟道导通电压时,所述第五增强型MOS管235的源漏极导通和所述第六增强型MOS管236的源漏极交替导通。所述第三电容223与所述第一电感241并联,发生并联谐振,使得所在电路处于高阻状态。MRI***的射频发射阶段,所述第一电极层110和所述第二电极层120之间几乎没有电流流通。所述第一磁场增强组件310产生的磁场减弱,进而减小所述第一磁场增强组件310对射频发射阶段磁场的影响,从而减小检测图像的伪影,提高检测图像的清晰度。
在MRI***的射频接收阶段,检测部位发射反馈信号,磁场的场强较小。所述第一磁场增强组件310产生的感应电压较小。加载的电压不能达到所述第五增强型MOS管235和所述第六增强型MOS管236的沟道导通电压,所述第五增强型MOS管235的源漏极导通和所述第六增强型MOS管236的源漏极不导通。所述第一电极层110和所述第二电极层120通过所述第三电容223连接。多个所述第一磁场增强组件310组成的所述第二筒形磁场增强器820处于谐振状态,起到增强磁场的作用。
在一个实施例中,所述第五增强型MOS管235和所述第六增强型MOS管236的沟道导通电压均在0至1V之间。且所述第五增强型MOS管235和所述第六增强型MOS管236的沟道导通电压相同,以使所述所述第二筒形磁场增强器820在射频接收阶段可以稳定增强磁场,反馈信号可以稳定输出。在一个实施例中,所述第五增强型MOS管235和所述第六增强型MOS管236的沟道导通电压为0.8V。
请参见图19,在一个实施例中,所述第一磁场增强组件310还包括第四电容224。所述第四电容224连接于所述第三电容223与所述第所述第一电极层110之间。所述第四电容224与所述第三电容223串联。所述第四电容224用于减小所述第三电容223的分压,提高所述第一磁场增强组件310抵抗强磁场的能力,降低所述第三电容223被击穿的概率。
在一个实施例中,所述第三电容223和所述第四电容224的电容值均相等。在MRI***的射频接收阶段,所述第三电容223和所述第四电容224上的分压相同,提高磁场的均匀性,减弱 磁场增强不一致导致的失真,提高图像质量。
请参见图20,本申请实施例提供一种第二磁场增强组件320。所述第二磁场增强组件320包括第一电极层110、第二电极层120和第一电介质层100。所述第一电极层110设置于所述第一表面101。所述第一电极层110覆盖部分所述第一表面101。与图15所示实施例相比,所述第二电极层120设置于所述第二表面102。所述第二电极层120覆盖部分所述第二表面102。所述第一电极层110在所述第一电介质层100的正投影与所述第二电极层120在所述第一电介质层100的正投影部分重叠形成第一结构电容150。
所述第一电极层110覆盖部分所述第一表面101指的是所述第一表面101还有部分没有被所述第一电极层110覆盖。所述第二电极层120覆盖部分所述第二表面102指的是所述第二表面102还有部分没有被所述第二电极层120覆盖。所述第一电极层110和所述第二电极层120在所述第一电介质层100的正投影有部分重叠。所述第一电极层110和所述第二电极层120相对设置的部分构成所述第一结构电容150。所述第一电极层110和所述第二电极层120在所述第一电介质层100的正投影不重叠的部分可以作为传输导线,起到等效电感的作用。所述第一结构电容150和所述等效电感可以形成LC振荡电路。用在谐振频率较低的场合时,具有较小容值的所述第一结构电容150就能使得多个所述第二磁场增强组件320构成的所述第二筒形磁场增强器820的谐振频率降低到磁共振***射频线圈的频率,从而能够有效提高磁场强度。
所述第二磁场增强组件320形成所述第一结构电容150的部分产生的磁场平行于所述第一电介质层100所在的平面。而平行于所述第一电介质层100的磁场基本无法起到检测的作用,属于无效磁场。所述第二磁场增强组件320中构成等效电感的部分产生的磁场垂直于所述第一电介质层100,能够产生对探测区域有作用的有效磁场。
在一个实施例中,所述第一电极层110在所述第一电介质层100的正投影与所述第二电极层120在所述第一电介质层100的正投影重叠部分所占的面积小于所述第一表面101的面积的一半或所述第二表面102的面积的一半。因此,所述第一电介质层100构成所述第一结构电容150的面积小于所述第一电介质层100的面积的一半。通过减小所述第一结构电容150面积,能够减小所述第一结构电容150的功耗。所述第一电介质层100构成所述第一结构电容150的面积小于所述第一电介质层100的面积的一半,还能够减小所述第二磁场增强组件320与其他级联的超构表面的耦合程度,显著提高所述第二磁场增强组件320的性能。
所述第一电介质层100可以起到支撑所述第一电极层110和所述第二电极层120的作用。所述第一电介质层100可以为长方形的板状结构。所述第一电介质层100可以为绝缘材料。在一个实施例中,所述第一电介质层100的材料可以为玻璃纤维环氧树脂板。所述第一电极层110和所述第二电极层120也可以为长方形的板状结构。所述第一电极层110和所述第二电极层120的材料可以由导电非磁性材料构成。在一个实施例中,所述第一电极层110和所述第二电极层120的材料可以为金、银、铜等金属材料。
在一个实施例中,所述第一电极层110和所述第二电极层120的厚度可以相等。所述第一电极层110、所述第二电极层120和所述第一电介质层100层叠设置。所述第一电极层110、所述第二电极层120和所述第一电介质层100所在的平面可以平行。
请参见图21和图22,在一个实施例中,所述第一电介质层100包括相对的第一端103和第二端104。所述第一电极层110由所述第二端104向所述第一端103延伸。所述第二电极层120由所述第一端103向所述第二端104延伸。所述第一电极层110在所述第一电介质层100的正投影与所述第二电极层120在所述第一电介质层100的正投影部分重叠形成所述第一结构电容150。即所述第一电极层110和所述第二电极层120分别由所述第一电介质层100相对的两端向所述第一电介质层100的中部延伸。所述第一电极层110和所述第二电极层120在所述第一电介质层100的正投影具有重合部分。所述重合部分远离所述第一电介质层100的两端。
所述第一电极层110和所述第二电极层120的长度小于所述第一电介质层100的长度的四分之三,大于所述第一电介质层100的四分之一。在该范围内,所述第一结构电容150的容值较小,可以降低功功耗。所述有效电感的长度较长,能够有效增强磁场,提高所述第二磁场增强组件320对图像信噪比的提升效果。
所述第一电极层110和所述第二电极层120的正投影的重合部分位于所述第一电介质层100中部。在所述重合部分,所述第一电极层110、所述第一电介质层100和所述第二电极层120构成所述第一结构电容150。所述第一电极层110、所述第二电极层120在所述第一电介质层100未重叠的部分可以构成传输线,起到电感的作用。所述第一电极层110和所述第二电极层120在所述第一电介质层100未叠的部分也可以作为等效电感。所述等效电感与所述第一结构电容150形成LC振荡电路。
所述第一电极层110和所述第二电极层120为宽度相同的条形,并具有相同的延伸方向。所述第一电极层110和所述第二电极层120的延伸方向可以在一条直线上,因此能够减小所述第二磁场增强组件320的宽度,减小所述第二磁场增强组件320的体积。
在一个实施例中,所述第一电极层110和所述第二电极层120在所述第一电介质层100正投影重合的部分位于所述第一电介质层100的中部。所述第一结构电容150位于所述第一电介质层100的中部。
所述第一电介质层100的中部可以为所述第一电介质层100中远离所述第一电介质层100边缘的部分。所述第一电介质层100的中部可以为所述第一电介质层100的中间,也可以为所述第一电介质层100中间偏左或者偏右的位置。所述第一结构电容150位于所述第一电介质层100的中部能够有效提高所述第二磁场增强组件320结构的对称性,进而提高磁场的均匀性。
在一个实施例中,所述第二磁场增强组件320的目标频率范围可以为60MHz到150MHz。在一个实施例中,所述第二磁场增强组件320的目标频率范围可以为63.8MHz(对应磁共振***的主磁场BO为1.5T)或者128MHz(对应磁共振***的主磁场BO为3T)。所述第一电介质 层100可以为长方形。所述第一电介质层100的长度可以为250毫米。所述第一电极层110和所述第二电极层120在所述第一电介质层100的正投影重合的部分的长度可以为20毫米。即所述第二磁场增强组件320能够产生有效磁场的长度为230毫米。所述第二磁场增强组件320能够产生有效磁场的面积显著增加。
请参见图23,在一个实施例中,所述第二磁场增强组件320还包括第一开关控制电路430,所述第一开关控制电路430连接于所述第一电极层110和所述第二电极层120之间。所述开关控制电路430用于在MRI***的射频发射阶段导通,在MRI***的射频接收阶段断开。
所述第一开关控制电路430的两端连接在所述第一电极层110和所述第二电极120层之间。即所述第一开关控制电路430可以与所述第一结构电容150并联。因此,当所述第一开关控制电路430导通时,所述第一电极层110和所述第二电极层120电连接。所述第一开关控制电路430关断时,所述第一电极层110和所述第二电极层120之间断开。所述第一开关控制电路430的开启电压可以大于1伏。即当所述第一电极层110和所述第二电极层两端的压差大于1伏时,所述第一开关控制电路430导通。当所述第一电极层110和所述第二电极层120之间的压差小于1伏时,所述第一开关控制电路430断开。
请参见图24,在MRI***的射频发射阶段,由于第一电极层110和所述第二电极层120上的压差较大,所述第一开关控制电路430导通。所述第一电极层110和所述第二电极层120电连接。此时所述第一电极层110和所述第二电极层120无法构成所述第一结构电容150。即所述第二磁场增强组件320不具有谐振性能。因此所述第二磁场增强组件320无法对射频发射场起到增强的作用。
而在MRI***的射频接收阶段,所述第一电极层110和所述第二电极层120上的压差较小,所述第一开关控制电路430关断。所述第一电极层110和所述第二电极层断开。所述第一电极层110和所述第二电极层120构成所述第一结构电容150。因此,所述第二磁场增强组件320构成的所述第二筒形磁场增强器820在MRI***的射频接收阶段具有谐振频率。所述所述第二筒形磁场增强器820可以对射频发射场起到增强的作用。
请参见图25,基于传统技术和本申请实施例提供的第二磁场增强组件320的MRI图像增强效果图。
a为磁共振***通常采用的体线圈,其图像信噪比很低,颗粒感严重;
b当所述第二磁场增强组件320不设置所述第一开关控制电路430时,形成的图像中出现了很多伪影,这是由于第二磁场增强组件320干扰射频发射场导致的;
c由本申请实施例提供的所述第二磁场增强组件320构成的所述第二筒形磁场增强器820,其图像信噪比高,图像清晰细腻,并且没有引入伪影。因此,多个所述第二磁场增强组件320构成的所述第二筒形磁场增强器820具有更好的序列普适性。
在一个实施例中,所述第一开关控制电路430的一端连接于所述第一电极层110与所述第二 电极层120在所述第一电介质层100的正投影具有重合的部分。所述第一开关控制电路430的另一端连接于所述第二电极层120与所述第一电极层110在所述第一电介质层100的正投影具有重合的部分。所述第一开关控制电路430连接的所述第一电极层110的位置,对应构成所述第一结构电容150。因此能够避免所述第一开关控制电路430连接在所述第一电极层110未构成所述第一结构电容150的部分。进而避免所述第一电极层110未构成所述第一结构电容150部分的等效电感造成的影响。
请参见图26,在一个实施例中,所述第二磁场增强组件320还包括第一外接电容440。所述第一外接电容440的两端分别与所述第一电极层110和所述第二电极层120连接。所述第一外接电容440可以为与所述第一电极层110和所述第二电极层120并联的可调电容。当所述第二磁场增强组件320的使用场合固定时,例如多个所述第二磁场增强组件320构成的所述第二筒形磁场增强器820的谐振频率确定时,所述第一外接电容440可以为固定电容。可以理解,所述第一外接电容440固定电容或者可调电容均在保护范围之内。
所述第一外接电容440与所述第一电极层110、所述第二电极层和所述第一电介质层100构成的结构电容配合可以调节多个所述第二磁场增强组件320构成的所述第二筒形磁场增强器820的谐振性能。
请参见图27,在一个实施例中,所述第一开关控制电路430包括第一二极管431和第二二极管432。所述第一二极管431的阳极与所述第一电极层110连接。所述第一二极管431的阴极与所述第二电极层120连接。所述第二二极管432的阴极与所述第一电极层110连接,所述第二二极管432的阳极与所述第二电极层120连接。
可以理解,所述第一二极管431和所述第二二极管432的导通电压可以在0伏到1伏。在一个实施例中,所述第一二极管431和所述第二二极管432的导通电压可以为0.8V。所述第一二极管431和所述第二二极管432分别串联在所述第一电极层110和所述第二电极层之间,所述第一二极管431和所述第二二极管432反接。
由于MRI***的射频的交流特性,所述第一电极层110和所述第二电极层120产生的感应电压也是交流电压。在MRI***的射频发射阶段,由于所述第一电极层110和所述第二电极层120之间的电压差已经超过所述第一二极管431和所述第二二极管432的导通电压。因此无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第一二极管431和所述第二二极管432总有一个处于导通状态。因此将所述第一电极层110和所述第二电极层电连接。
而在MRI***的射频接收阶段,由于所述第一电极层110和所述第二电极层之间的电压差小于所述第一二极管431和所述第二二极管432的导通电压。因此无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第一二极管431和所述第二二极管432均处于不导通的状态。
请参见图28,在一个实施例中,所述第一开关控制电路430还包括第一增强型MOS管433 和第二增强型MOS管434。所述第一增强型MOS管433的源极与所述第二电极层连接。所述第一增强型MOS管433的漏极与所述第一电极层110连接。所述第一增强型MOS管433的栅极与所述第一电极层110连接。所述第二增强型MOS管434的源极与所述第一电极层110连接。所述第二增强型MOS管434的漏极与所述第二电极层120连接。所述第二增强型MOS管434的栅极与所述第二电极层120连接。即所述第一增强型MOS管433和第二增强型MOS管434反接。
所述第一增强型MOS管433和所述第二增强型MOS管434在栅极电压小于阈值电压时不导通,也可以理解为只有当栅极电压的大小大于其阈值电压时才能出现导电沟道。
可以理解,在MRI***的射频发射阶段,所述第一电极层110和所述第二电极层120之间的电压差已经超过所述第一增强型MOS管433和所述第二增强型MOS管434导通的阈值电压。因此,无论所述第一电极层110和所述第二电极层哪个的电压高,所述第一增强型MOS管433和所述第二增强型MOS管434总有一个处于导通状态。因此,将所述第一电极层110和所述第二电极层电连接。
而在MRI***的射频接收阶段,由于所述第一电极层110和所述第二电极层之间的电压差小于所述第一增强型MOS管433和所述第二增强型MOS管434导通的阈值电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第一增强型MOS管433和所述第二增强型MOS管434均处于不导通的状态。
请参见图29,在一个实施例中,所述第二磁场增强组件320还包括第二外接电容442、所述第三外接电容443和第二开关控制电路450。所述第二外接电容442和所述第三外接电容443串联于所述第一电极层110和所述第二电极层120之间。所述第二开关控制电路450的一端与所述第一电极层110连接。所述第二开关控制电路450的另一端连接于所述第二外接电容442和第三外接电容443之间。所述第二开关控制电路450用于在MRI***的射频发射阶段导通,在MRI***的射频接收阶段断开。
所述第二外接电容442和所述第三外接电容443可以为固定电容,也可以为可调电容。当所述第二磁场增强组件320所在回路的谐振频率确定时,可以选择合适的固定电容作为所述第二外接电容442和所述第三外接电容443。当所述第二磁场增强组件320所在回路的谐振频率要求根据需要调整时,所述第二外接电容442和所述第三外接电容443可以为可调电容。
可以理解,MRI***的射频发射阶段和射频接收阶段在时间顺序上有几十到几千毫秒的差别。射频发射阶段和射频接收阶段的射频功率相差3个数量级。射频发射阶段结构电容上的电压在几伏到几百伏之间。而在射频接收阶段,所述结构电容两端的电压在毫伏级别。
所述第二开关控制电路450的一端与所述第一电极层110连接。所述第二开关控制电路450的另一端连接于所述第二外接电容442和第三外接电容443之间。因此,当所述第二开关控制电路450导通时,所述第二外接电容442被短路。只有所述第三外接电容443连接在所述第一电极 层110和所述第二电极层120之间。所述第二开关控制电路450关断时,第二外接电容442和第三外接电容443串联于所述第一电极层110和所述第二电极层120之间。
所述第二开关控制电路450的开启电压可以大于1伏。当所述第一电极层110和所述第二电极层两端的压差大于1伏时,所述第二开关控制电路450导通。当所述第一电极层110和所述第二电极层120之间的压差小于1伏时,所述第二开关控制电路450断开。
在MRI***的射频发射阶段,由于结构电容上的压差较大,所述第二开关控制电路450导通。所述第二外接电容442被短路。只有所述第三外接电容443连接在所述第一电极层110和所述第二电极层120之间。通过调节所述第三外接电容443可以调节所述第二磁场增强组件320所在的回路在MRI***的射频发射阶段的失谐程度。所述第二磁场增强组件320所在的回路在MRI***的射频发射阶段的失谐程度可以通过所述第三外接电容443调节。第三外接电容443接入电路,等效电容较大,谐振频率低。
通过所述第三外接电容443可以精确调节多个所述第二磁场增强组件320构成的所述第二筒形磁场增强器820的谐振频率,使得受测区域保持原来的磁场强度。通过所述第三外接电容443调节所述第二筒形磁场增强器820的谐振频率,可以消除所述第二磁场增强组件320对射频发射阶段的干扰,提高了所述第二筒形磁场增强器820的临床实用性。进而,所述第二筒形磁场增强器820适用于磁共振***的所有的序列。
而在MRI***的射频接收阶段,所述结构电容上的压差较小,所述第二开关控制电路450关断。所述第二外接电容442和所述第三外接电容443串联于所述第一电极层110和所述第二电极层120之间。所述第二外接电容442和所述第三外接电容443的等效电容小,所述第二磁场增强组件320所在的回路谐振频率高。
请参见图30,通过调节所述第二外接电容442和所述第三外接电容443能够使所述第二磁场增强组件320所在的回路在MRI***的射频接收阶段具有稳定的谐振频率。从而,所述第二磁场增强组件320所在的回路在接收阶段的谐振频率达到MRI***的工作频率。所述第二磁场增强组件320具有非线性响应特性。所述第二磁场增强组件320可以对射频发射场起到增强的作用。
请参见图31,在一个实施例中,所述第二开关控制电路450包括第三二极管451和第四二极管452。所述第三二极管451的阳极与所述第一电极层110连接,所述第三二极管451的阴极连接于所述第二外接电容442和所述第三外接电容443之间。所述第四二极管452的阳极连接于所述第二外接电容442和所述第三外接电容443之间。所述第四二极管452的阴极与所述第一电极层110连接。
可以理解,所述第三二极管451和所述第四二极管452的导通电压可以在0伏到1伏。在一个实施例中,所述第三二极管451和所述第四二极管452的导通电压可以为0.8V。所述第三二极管451和所述第四二极管452分别串联在所述第一电极层110和所述第二电极层之间,即所述 第三二极管451和所述第四二极管452反接。
由于MRI***的射频交流特性,所述第一电极层110和所述第二电极层120产生的感应电压也是交流电压。在MRI***的射频发射阶段,由于所述第一电极层110和所述第二电极层120之间的电压差已经超过所述第三二极管451和所述第四二极管452的导通电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第三二极管451和所述第四二极管452总有一个处于导通状态。因此,所述第二外接电容442被短路。
而在MRI***的射频接收阶段,由于所述第一电极层110和所述第二电极层之间的电压差小于所述第三二极管451和所述第四二极管452的导通电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第三二极管451和所述第四二极管452均处于不导通的状态。所述第二外接电容442和所述第三外接电容443串联于所述第一电极层110和所述第二电极层120之间。
请参见图32,在一个实施例中,所述第二开关控制电路450还包括第三增强型MOS管453和第四增强型MOS管454。所述第三增强型MOS管453的源极接于所述第二外接电容442和所述第三外接电容443之间。所述第三增强型MOS管453的漏极与所述第一电极层110连接。所述第三增强型MOS管的栅极453与所述第一电极层110连接。所述第四增强型MOS管454的源极与所述第一电极层110连接。所述第四增强型MOS管454的漏极连接于所述第二外接电容442和所述第三外接电容443之间。所述第四增强型MOS管454的栅极连接于所述第二外接电容442和所述第三外接电容443之间。即所述第三增强型MOS管453和第四增强型MOS管454反接。
所述第三增强型MOS管453和所述第四增强型MOS管454在栅极电压小于阈值电压时不导通,也可以理解为只有当栅极电压的大小大于其阈值电压时才能出现导电沟道。
可以理解,在MRI***的射频发射阶段,由于所述第一电极层110和所述第二电极层120之间的电压差已经超过所述第三增强型MOS管453和所述第四增强型MOS管454导通的阈值电压。因此,无论所述第一电极层110和所述第二电极层哪个的电压高,所述第三增强型MOS管453和所述第四增强型MOS管454总有一个处于导通状态。因此,所述第二外接电容442被短路。
而在MRI***的射频接收阶段,由于所述第一电极层110和所述第二电极层之间的电压差小于所述第三增强型MOS管453和所述第四增强型MOS管454导通的阈值电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第三增强型MOS管453和所述第四增强型MOS管454均处于不导通的状态。所述第二外接电容442和所述第三外接电容443串联于所述第一电极层110和所述第二电极层120之间。
所述第二开关控制电路450在MRI***的射频接收阶段断开,通过所述第一结构电容150、所述第二外接电容442以及所述第三外接电容443之间的配合,能够进一步提高磁场增强的效果。
在一个实施例中,所述第二开关控制电路450的一端连接于所述第一电极层110与所述第二电极层120在所述第一电介质层100的正投影重合部分的位置。所述第二开关控制电路450的另一端连接于所述第二电极层120与所述第一电极层110在所述第一电介质层100的正投影重合部分的位置。所述第二开关控制电路450连接的所述第一电极层110的位置,是构成所述第一结构电容150的部分。因此,能够避免所述第二开关控制电路450连接在所述第一电极层110未构成所述第一结构电容150的部分。进而避免所述第一电极层110未构成所述第一结构电容150部分的等效电感产生的影响。
请参见图33,在一个实施例中,所述第二磁场增强组件320还包括第四外接电容444、第五外接电容445和第三开关控制电路460。所述第一电极层110在所述第一电介质层100的正投影与所述第二电极层120在所述第一电介质层100的正投影部分重叠形成第一结构电容150。所述第四外接电容444的两端连接于所述第一电极层110和所述第二电极层120之间。所述第五外接电容445和第三开关控制电路460串联于所述第一电极层110和所述第二电极层120之间,所述第三开关控制电路460用于在MRI***的射频发射阶段导通,在MRI***的射频接收阶段断开。
所述第四外接电容444和所述第五外接电容445可以为固定电容,也可以为可调电容。当所述第二磁场增强组件320所在回路的谐振频率确定时,可以选择合适的固定电容作为所述第四外接电容444和所述第五外接电容445。当所述第二磁场增强组件320所在回路的谐振频率要求根据需要调整时,所述第四外接电容444和所述第五外接电容445可以为可调电容。
所述第二外接电容442和所述第三外接电容443可以为固定电容,也可以为可调电容。当所述第二磁场增强组件320所在回路的谐振频率确定时,可以选择合适的固定电容作为所述第二外接电容442和所述第三外接电容443。当所述第二磁场增强组件320所在回路的谐振频率要求根据需要调整时,所述第二外接电容442和所述第三外接电容443可以为可调电容。
可以理解,MRI***的射频发射阶段和射频接收阶段在时间顺序上有几十到几千毫秒的差别。射频发射阶段和射频接收阶段的射频功率相差3个数量级。射频发射阶段结构电容上的电压在几伏到几百伏之间。而在射频接收阶段,所述结构电容两端的电压在毫伏级别。
所述第三开关控制电路460与所述第五外接电容445串联于所述第一电极层110和所述第二电极层120之间。因此,当所述第三开关控制电路460导通时,所述第五外接电容445和所述第四外接电容444并联于所述第一电极层110和所述第二电极层120。相比于两个电容串联,当所述第二磁场增强组件320的总容值相等时,所述第五外接电容445和所述第四外接电容444并联的容值更大。因此,所需的所述第一结构电容150的容值可以较小。因此,所述第二磁场增强组件320可以具有更低的损耗。
在MRI***的射频发射阶段,所述第二磁场增强组件320所在回路的谐振频率偏离磁共振***工作频率较远。因此,通过调节所述第五外接电容445和所述第四外接电容444,能够保证在磁共振***的射频发射阶段,有所述第二磁场增强组件320和没有所述第二磁场增强组件320 的磁场强度相同。
在MRI***的发射阶段,所述第一电极层110和所述第二电极层120之间的电压差较大,所述第三开关控制电路460导通。所述第四外接电容444和所述第五外接电容445串联于所述第一电极层110和所述第二电极层120之间。
而在MRI***的射频接收阶段,所述述第一电极层110和所述第二电极层120之间的电压差较小,所述第三开关控制电路460关断。只有所述第四外接电容444串联于所述第一电极层110和所述第二电极层120之间。通过调节所述第四外接电容444,能够调节所述第二磁场增强组件320所在回路的谐振频率,使得所述谐振频率与MRI***的射频线圈的频率相等,从而大幅增强射频接收场,提高图像信噪比。
请参见图34,通过调节所述第四外接电容444和所述第五外接电容445,能够使得多个所述第二磁场增强组件320构成的第二筒形磁场增强器820在射频接收阶段具有良好的谐振频率。最终使得多个所述第二磁场增强组件320构成的第二筒形磁场增强器820在接收阶段的谐振频率达到磁共振***的工作频率。
请参见图35,在一个实施例中,所述第三开关控制电路460包括第五二极管461和第六二极管462。所述第五二极管461的阳极与所述第一电极层110连接。所述第五二极管461的阴极与所述第五外接电容445的一端连接。所述第六二极管462的阳极与所述第五外接电容445的一端连接。所述第六二极管462的阴极与所述第一电极层110连接。
可以理解,所述第五二极管461和所述第六二极管462的导通电压可以在0伏到1伏。在一个实施例中,所述第五二极管461和所述第六二极管462的导通电压可以为0.8V。所述第五二极管461和所述第六二极管462分别串联在所述第一电极层110和所述第二电极层之间,即所述第五二极管461和所述第六二极管462反接。
由于MRI***的射频交流特性,所述第一电极层110和所述第二电极层120产生的感应电压也是交流电压。在MRI***的射频发射阶段,由于所述第一电极层110和所述第二电极层120之间的电压差已经超过所述第五二极管461和所述第六二极管462的导通电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第五二极管461和所述第六二极管462总有一个处于导通状态。因此,所述第四外接电容444和所述第五外接电容445并联于所述第一电极层110和所述第二电极层120之间。
而在MRI***的射频接收阶段,由于所述第一电极层110和所述第二电极层之间的电压差小于所述第五二极管461和所述第六二极管462的导通电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第五二极管461和所述第六二极管462均处于不导通的状态。只有所述第四外接电容444连接在所述第一电极层110和所述第二电极层120之间。
请参见图36,在一个实施例中,所述第三开关控制电路460还包括第五增强型MOS管463和第六增强型MOS管464。所述第五增强型MOS管463的源极连接于第五外接电容445的一 端。所述第五增强型MOS管463的漏极与所述第一电极层110连接。所述第五增强型MOS管463的栅极与所述第一电极层110连接。所述第六增强型MOS管464的源极与所述第一电极层110连接。所述第六增强型MOS管464的漏极与所述第五外接电容445的一端连接。所述第六增强型MOS管464的栅极与第五外接电容445的一端连接。即所述第五增强型MOS管463和所述第六增强型MOS管464反接。
可以理解,所述第五增强型MOS管463和所述第六增强型MOS管464在栅极电压小于阈值电压时不导通。也可以理解为,只有当栅极电压的大小大于其阈值电压时才能出现导电沟道。
在MRI***的射频发射阶段,由于所述第一电极层110和所述第二电极层120之间的电压差已经超过所述第五增强型MOS管463和所述第六增强型MOS管464导通的阈值电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第五增强型MOS管463和所述第六增强型MOS管464总有一个处于导通状态。因此,所述第四外接电容444和所述第五外接电容445并联于所述第一电极层110和所述第二电极层120之间。
而在MRI***的射频接收阶段,由于所述第一电极层110和所述第二电极层之间的电压差小于所述第五增强型MOS管463和所述第六增强型MOS管464导通的阈值电压。因此,无论所述第一电极层110和所述第二电极层120哪个的电压高,所述第五增强型MOS管463和所述第六增强型MOS管464均处于不导通的状态。所述第四外接电容444连接于所述第一电极层110和所述第二电极层120之间。
在一个实施例中,所述第三开关控制电路460的一端连接于所述第一电极层110与所述第二电极层120在所述第一电介质层100的正投影的重合部分的位置。所述第三开关控制电路460的另一端连接于所述第二电极层120与所述第一电极层110在所述第一电介质层100的正投影的重合部分的位置。所述第三开关控制电路460连接的所述第一电极层110的位置,是构成所述第一结构电容150的部分。因此,能够避免所述第三开关控制电路460连接在所述第一电极层110未构成所述第一结构电容150的部分。进而避免所述第一电极层110未构成所述第一结构电容150部分的等效电感产生的影响。
请参见图37至图39,在一个实施例中,所述第三磁场增强组件330还包括设置于所述第一表面101的第三电极层130。与图20所示实施例相比,所述第二电极层120靠近所述第一电介质层100的中部设置。所述第三电极层130由所述第一端103向所述第二端104延伸。所述第三电极层130覆盖部分所述第一表面101,并与所述第一电极层110间隔设置。所述第二电极层120与所述第三电极层130电连接。
所述第三电极层130的厚度可以与所述第一电极层110的厚度相同。所述第三电极层130可以绕过所述第一电介质层100与所述第二电极层120连接。所述第三电极层130也可以通过穿过所述第一电介质层100的导线与所述第二电极层120连接。所述第三磁场增强组件330位于磁共振***的激发场时,所述第一电极层110和所述第三电极层130可以具有电感的作用。
所述第三电极层130可以由所述第一电介质层100的第一端103向所述第二端104延伸,并逐渐靠近所述第二电极层120。所述第三电极层130与所述第一电极层110绝缘,避免了所述第一电极层110和所述第二电极层120构成的所述第一结构电容150被短路。所述第一电极层110和所述第三电极层130设置于所述第一电介质层100的同侧。因此,当将所述第三磁场增强组件330安装于支架时,所述第二表面102靠近支架安装,可以避免所述第一电极层110和所述第三电极层130被支架损坏。
在一个实施例中,所述第三电极层130的长度小于所述第一电解质层100长度的二分之一。且所述第三电极层130的长度大于所述第一电介质层100长度的三分之一。在所述第一电介质层100长度的三分之一至所述第一电解质层100长度的二分之一的范围内,所述第三电极层130构成的等效电感具有较大的长度。进而,所述第三电极层130能够有效提高所述第三磁场增强组件330产生有效磁场的面积。
在一个实施例中,所述第三电极层130为条形,所述第三电极层130的延伸方向和宽度与所述第一电极层110相同。所述第三电极层130和所述第一电极层110的宽度可以相同。且所述第三电极层130和所述第一电极层110可以位于同一直线。所述第一电介质层100的宽度可以与在所述第三电极层130和所述第一电极层110的宽度相等,或者略大于所述三电极层130和所述第一电极层110的宽度。因此可以尽量减小所述第一电介质层100的宽度。
请参见图38与图39,在一个实施例中,所述第一电介质层100开设有第一过孔103。所述第一过孔103中设置有电极材料。所述第三电极层130通过所述电极材料与所述第二电极层120电连接。所述电极材料可以与所述第三电极层130和所述第二电极层120的材料相同,可以降低电阻。在一个实施例中,位于所述第一过孔103中的电极材料和所述第一电极、所述第三电极层130一体成型。
在一个实施例中,所述第三电极层130靠近所述第一电极层110的一端与所述第一过孔103的正投影重合。所述第二电极层120远离所述第一电极层110的一端与所述第一过孔103的正投影重合。所述第三电极层130与位于所述第一过孔103中靠近所述第一表面101的电极材料接触。所述第二电极层120与所述第一过孔103中靠近所述第二表面102的电极材料接触。因此,所述第三电极层130、所述第二电极层120通过所述第一过孔103中的电极材料电连接。
请参见图40,在一个实施例中,所述第一电极层110靠近所述第二电极层120的一端具有第一豁口411。所述第二电极层120靠近所述第一电极层110的一端具有第二豁口412。所述第一豁口411和所述第二豁口412在所述第一电介质层100的正投影重合。所述第一豁口411和所述第二豁口412的尺寸可以相同。所述第一豁口411和所述第二豁口412。
当将所述第三磁场增强组件330位于磁共振***中的激发场后,所述第一电极层110和所述第二电极层120在所述第一电介质层100的正投影的重合部分可以构成所述第一结构电容150。所述第一豁口411和所述第二豁口412能够优化局部磁场分布,能够提高检测部位特定位置的检 测效果。
请参见图41,在一个实施例中,所述第一电极层110靠近所述第二电极层120的一端具有第三豁口413。所述第三豁口413与所述第一豁口411间隔设置。所述第二电极层120靠近所述第一电极层110的一端具有第四豁口414。所述第四豁口414与所述第二豁口412间隔设置。所述第三豁口413和所述第四豁口414在所述第一电介质层100的正投影重合。可以理解,所述第一豁口411与所述第三豁口413的形状和大小可以相同。所述第二豁口412和所述第四豁口414的大小和形状可以相同。所述第一豁口411与所述第三豁口413之间的距离可以相同。所述第二豁口412和所述第四豁口414之间的距离可以相同。所述第三豁口413和所述第四豁口414可以位于所述第一电极层110和所述第二电极层120在所述第一电介质层100上正投影的重叠部分。所述第三豁口413和所述第四豁口414进一步优化局部磁场分布,提高检测部位特定位置的检测效果。
请参见图42,在一个实施例中,所述第四磁场增强组件340包括第二电介质层831、第五电极层834、第六电极层833以及第七电极层832。所述第二电介质层831具有相对设置的第三表面805与第四表面806。所述第二电介质层831具有相对设置的第三端881与第四端882。所述第七电极层832设置于所述第三表面805。所述第七电极层832覆盖所述第三表面805。也可以理解为,所述第七电极层832全部覆盖所述第三表面805。所述第六电极层833设置于所述第四表面806。所述第六电极层833覆盖部分所述第四表面806。所述第六电极层833靠近所述第三端881设置。所述第五电极层834与所述第六电极层833间隔设置于所述第四表面806。所述第五电极层834覆盖部分所述第四表面806。所述第五电极层834靠近所述第四端882设置。
所述第六电极层833在所述第二电介质层831的正投影,位于所述第七电极层832在所述第二电介质层831的正投影中,形成第二结构电容807。也可以理解为,所述第六电极层833在所述第二电介质层831的正投影和所述第七电极层832在所述第二电介质层831的正投影的一部分重合。在重合部分,所述第六电极层833、所述第二电介质层831以及所述第七电极层832形成所述第二结构电容807。
所述第五电极层834在所述第二电介质层831的正投影,位于所述第七电极层832在所述第二电介质层831的正投影中,形成第三结构电容808。也可以理解为,所述第五电极层834在所述第二电介质层831的正投影和所述第七电极层832在所述第二电介质层831的正投影的一部分重合。在重合部分,所述第五电极层834、所述第二电介质层831以及所述第七电极层832形成所述第三结构电容808。
所述第二结构电容807与所述第三结构电容808之间的所述第七电极层832形成传输线,将所述第二结构电容807与所述第三结构电容808串联连接。所述第二结构电容807与所述第三结构电容808设置于所述第二电介质层831的两端。
在一个实施例中,所述第三磁场增强组件330、所述第二磁场增强组件320以及所述第一磁 场增强组件310均具有中部设置的电容。所述第四磁场增强组件340具有两端设置的结构电容。当所述内磁场增强组件822为所述第三磁场增强组件330或者所述第二磁场增强组件320或者所述第一磁场增强组件310,所述外磁场增强组件812为所述第四磁场增强组件340时,所述双核磁场增强装置30中分别在两端和中部形成了电容。
所述第一筒形磁场增强器810中所述外磁场增强组件812的结构电容设置在两端。所述第二筒形磁场增强器820中所述内磁场增强组件822的电容设置在中间位置。所述第二筒形磁场增强器820与所述第一筒形磁场增强器810嵌套设置时,电容均匀分布在中部和两端。电容均匀分布在中部和两端,使得电场主要分布在了中部和两端。进而,电场主要分布在了中部和两端,减小了所述第二筒形磁场增强器820与所述第一筒形磁场增强器810之间的电耦合。所述第二筒形磁场增强器820与所述第一筒形磁场增强器810之间的电耦合减小,有利于实现双核MRI两个信号场的同时增强。进一步,所述第二筒形磁场增强器820与所述第一筒形磁场增强器810之间的电耦合减小,提高了所述双核磁场增强装置30的磁场增强效果,更有利于MRI***成像。
请参见图43,在一个实施例中,沿环绕所述第一筒形支架811的第一中心轴线的方向,所述第二结构电容807和所述第三结构电容808之间的所述第七电极层832的宽度小于所述第二结构电容807和所述第三结构电容808对应的所述第七电极层832的宽度。
本实施例中,所述第二结构电容807与所述第三结构电容808之间的所述第七电极层832形成传输线,将所述第二结构电容807与所述第三结构电容808连接。传输线对应的电极层与电极层之间相对设置会形成杂散电容。所述第二结构电容807与所述第三结构电容808之间的所述第七电极层832的宽度小于所述第二结构电容807和所述第三结构电容808对应的所述第七电极层832的宽度,会使得传输线的宽度变小,进而使得电极层与电极层之间的相对面积变小。
因此,传输线的宽度变小,减小了形成的杂散电容。因此,在不影响所述第二结构电容807与所述第三结构电容808连接的情况下,减小了杂散电容,更有利于磁场均匀分布,提高了MRI图像质量。
由于所述第一电极层110的宽度、所述第二电极层120的宽度以及所述第二结构电容807与所述第三结构电容808之间的所述第七电极层832的宽度都变小,传输线电极之间的相对面积变小。传输线电极之间的相对面积变小,减小了形成的杂散电容。杂散电容减小,更有利于磁场均匀分布,提高了MRI图像质量。
当所述外磁场增强组件812与所述内磁场增强组件822为本实施例中的所述第四磁场增强组件340时,所述外磁场增强组件812与所述内磁场增强组件822错位设置。所述外磁场增强组件812与所述内磁场增强组件822不相对设置,间隔设置。两个所述外磁场增强组件812之间间隔设置一个所述内磁场增强组件822。由于所述第七电极层832的中间部分的宽度小于两端的宽度,所述外磁场增强组件812的传输线电极与所述内磁场增强组件822的传输线电极之间不会相对设置,进而不会形成杂散电容。所述双核磁场增强装置30不会形成杂散电容,有利于实现双核 MRI两个信号场的同时增强,进一步提高了磁场增强效果,更有利于MRI***成像。
请参见图44与图45,所述第四磁场增强组件340包括第二电介质层831、第七电极层832、第六电极层833、第一耗尽型MOS管231与第二耗尽型MOS管232。与图42所示的实施例相比,所述第七电极层832设置于所述第三表面805。所述第七电极层832靠近所述第四端882设置。所述第六电极层833设置于所述第三表面805。所述第六电极层833与所述第七电极层832间隔设置。所述第六电极层833靠近所述第三端881设置。所述第一耗尽型MOS管231的源极与所述第六电极层833连接。所述第一耗尽型MOS管231的栅极和漏极连接。所述第二耗尽型MOS管232的栅极和漏极连接。所述第二耗尽型MOS管232的栅极和漏极与所述第一耗尽型MOS管231的栅极和漏极连接。所述第二耗尽型MOS管232的源极与所述第七电极层832连接。
所述第一耗尽型MOS管231与所述第二耗尽型MOS管232具有低压导通,高压截止的特性。并且,所述第一耗尽型MOS管231与所述第二耗尽型MOS管232,在室温下的夹断电压在1V左右,断开时间和恢复时间都在纳秒量级。
MRI***中射频发射阶段和射频接收阶段在时间顺序上有几十毫秒到几千毫秒的差别,可以快速实现所述第一耗尽型MOS管231与所述第二耗尽型MOS管232的导通和断开。MRI***的射频发射阶段和射频接收阶段的射频功率相差3个数量级。射频发射阶段线圈中的感应电压在几V到几百V之间,具体数值与所选的序列和翻转角有关。
所述第一耗尽型MOS管231与所述第二耗尽型MOS管232反向串联连接,能够控制所述第七电极层832与所述第六电极层833在射频发射阶段断开,且在射频接收阶段连接。在MRI***的射频发射阶段,通过所述第一耗尽型MOS管231与所述第二耗尽型MOS管232反向串联连接,可以适应于MRI***中的交流环境。无论如何变化,都能确保所述第一耗尽型MOS管231和所述第二耗尽型MOS管232中有一个发生截止,使得所述第六电极层833和所述第七电极层832断开,不连接。
在MRI***的射频发射阶段,感应电压较大,所述第一耗尽型MOS管231与所述第二耗尽型MOS管232处于断开状态,多个所述第四磁场增强组件340形成的磁场增强器处于断开状态,呈现失谐状态。所述所述第四磁场增强组件340中不存在电流,不产生会干扰射频的感应磁场,消除了磁场增强器对射频发射阶段磁场的影响。
在MRI***的射频接收阶段,所述第一耗尽型MOS管231与所述第二耗尽型MOS管232导通,进而确保所述第七电极层832与所述第六电极层833连接。多个所述第四磁场增强组件340形成的磁场增强器处于连接状态,能够呈现谐振状态,大幅度增强信号场,增强图像信噪比。
因此,通过所述第一耗尽型MOS管231和所述第二耗尽型MOS管232控制所述第七电极层832和所述第六电极层833在射频发射阶段断开,在射频接收阶段连接。通过所述第一耗尽型MOS管231和所述第二耗尽型MOS管232使得所述第四磁场增强组件340只能增强射频接收 场,不会对射频发射场进行增强,提高了图像信噪比。
所述第四磁场增强组件340通过所述第一耗尽型MOS管231与所述第二耗尽型MOS管232,引入非线性控制结构,使得多个所述第四磁场增强组件340形成的磁场增强器也具有非线性响应特性,能够适用于包括快速自旋回波序列在内的所有临床序列。
在一个实施例中,所述第二电介质层831还包括第四表面806。所述第四表面806与所述第三表面805相对设置。所述第四磁场增强组件340还包括第五电极层834与所述第八电极层835。与图42所示的实施例相比,所述第五电极层834设置于所述第四表面806。所述第五电极层834覆盖部分所述第四表面806。所述第五电极层834靠近所述第四端882设置。所述所述第八电极层835设置于所述第四表面806。所述所述第八电极层835覆盖部分所述第四表面806。所述所述第八电极层835靠近所述第三端881设置。
所述第五电极层834在所述第二电介质层831的正投影与所述第七电极层832在所述第二电介质层831的正投影部分重和,形成第三结构电容808。在重和部分,所述第七电极层832、所述第二电介质层831以及所述第五电极层834形成所述第三结构电容808。所述所述第八电极层835在所述第二电介质层831的正投影与所述第六电极层833在所述第二电介质层831的正投影部分重和,形成第二结构电容807。在重和部分,所述第六电极层833、所述第二电介质层831以及所述所述第八电极层835形成所述第二结构电容807。
所述第二结构电容807与所述第一耗尽型MOS管231之间的所述第六电极层833可以形成第一传输线。所述第二耗尽型MOS管232与所述第三结构电容808之间的所述第七电极层832可以形成第二传输线。所述第二结构电容807、所述第一耗尽型MOS管231、所述第二耗尽型MOS管232以及所述第三结构电容808通过第一传输线和第二传输线实现串联连接。因此,通过所述第二结构电容807、所述第一耗尽型MOS管231、所述第二耗尽型MOS管232以及所述第三结构电容808串联连接,可以对多个所述第四磁场增强组件340形成的磁场增强器的谐振频率进行调节,缩短了所述磁场增强器在放入核磁共振成像***之后的调节时间。
所述第四磁场增强组件340在磁场环境中会产生感应电压。所述第七电极层832和所述第六电极层833形成的传输线部分会形成寄生电容。寄生电容与所述第三结构电容808以及所述第二结构电容807之间是并联关系。在MRI***的射频接收阶段,所述第二结构电容807和所述第三结构电容808形成电容串联的结构,将感应电压分为多个,减小了所述第二结构电容807和所述第三结构电容808的分压。
进一步,所述第二结构电容807和所述第三结构电容808形成电容串联的结构,可以降低寄生电容上的电压。寄生电容上的电压减小,降低了寄生电容的危害,从而减小了负载效应。所述第四磁场增强组件340的负载效应减小,使得多个所述第四磁场增强组件340形成的所述磁场增强器的谐振频率不容易受到受测物体的影响,提高了所述磁场增强器的增强性能,增强了谐振频率的稳定性。
在一个实施例中,在所述第二结构电容807对应的重和部分,重合长度与重合面积有关。所述第二结构电容807和所述第三结构电容808都具有各自的正对面积。通过调节正对面积的大小,可以调控所述第六电极层833和所述所述第八电极层835构成的结构电容的电容值,使得由多个所述第四磁场增强组件340形成的磁场增强器与MRI***具有相同的工作频率。
其中,多个所述第四磁场增强组件340形成的所述磁场增强器的谐振频率由下式确定
Figure PCTCN2021114228-appb-000001
其中,L和C分别是多个所述第四磁场增强组件340形成的磁场增强器的谐振回路中的等效电感和等效电容。等效电容的值由每个单元的结构电容Cs决定。结构电容Cs与两电极板正对面积S的关系为
Figure PCTCN2021114228-appb-000002
其中,ε 0为真空介电常数,ε为所述第二电介质层831的相对介电常数。d为两电极板板间的距离(或者是所述第二电介质层831的厚度)。所以,通过调节正对面积的大小,可以调控结构电容的电容值,使得多个第四磁场增强组件340形成的所述磁场增强器具有目标谐振频率,也可以理解为与MRI***具有相同的工作频率。
请参见图46,在一个实施例中,在所述第二结构电容807对应的重和部分,所述第六电极层833和所述所述第八电极层835的重合长度为35mm。在所述第三结构电容808对应的重和部分,所述第七电极层832和所述第五电极层834的重合长度为35mm。
在一个实施例中,所述第二结构电容807与所述第一耗尽型MOS管231之间的所述第六电极层833的长度和所述第三结构电容808与所述第二耗尽型MOS管232之间的所述第七电极层832的长度相同。也可以理解为,由所述第三端881至所述第四端882的方向上,所述第一传输线和所述第二传输线的长度相同。
所述第一传输线和所述第二传输线,可以等效为电感和电阻。有效磁场分布在所述第一传输线和所述第二传输线之间。所述第三结构电容808和所述第二耗尽型MOS管232之间的有效磁场形成第一检测区域。所述第二结构电容807和所述第一耗尽型MOS管231之间的有效磁场形成第二检测区域。第一检测区域与第二检测区域相同。有效磁场形成的区域作为检测区域,对检测部位进行检测。本实施例中所述第四磁场增强组件340在所述第一耗尽型MOS管231和所述第二耗尽型MOS管232左右两侧形成两个相同的检测区域,更有利于所述第四磁场增强组件340形成均匀磁场,提高了MRI图像质量。
请参见图47与图48,在一个实施例中,所述第五磁场增强组件350包括第二电介质层831、第七电极层832、第六电极层833、第五电极层834以及第八电极层835。与图42所示的实施例相比,所述第七电极层832设置于所述第三表面805。所述第七电极层832靠近所述第四端882设置。所述第七电极层832覆盖部分所述第三表面805。所述第六电极层833设置于所述第四表面806,并覆盖部分所述第四表面806。所述第六电极层833靠近所述第三端881设置。所述第五电极层834与所述第六电极层833间隔设置于所述第四表面806。所述第五电极层834覆盖部分所述第四表面806。所述第五电极层834靠近所述第四端882设置。
所述第六电极层833在所述第二电介质层831的正投影,表征了所述第六电极层833的结构大小和形状。所述第七电极层832在所述第二电介质层831的正投影,表征了所述第七电极层832的结构大小和形状。所述第七电极层832在所述第二电介质层831的正投影和所述第六电极层833在所述第二电介质层831的正投影部分重叠以形成第四结构电容809。也可以理解为,所述第六电极层833和所述第七电极层832相对设置于所述第二电介质层831的两个表面,具有重合部分。在重合部位,所述第六电极层833、所述第二电介质层831以及所述第七电极层832形成了所述第四结构电容809。
所述第五电极层834在所述第二电介质层831的正投影,表征了所述第五电极层834的结构大小和形状。所述第五电极层834在所述第二电介质层831的正投影,位于所述第七电极层832在所述第二电介质层831的正投影中,形成第三结构电容808。也可以理解为,所述第五电极层834在所述第二电介质层831的正投影和所述第七电极层832在所述第二电介质层831的正投影部分重合。在重合部位,所述第五电极层834、所述第二电介质层831以及所述第七电极层832形成了所述第三结构电容808。
所述第八电极层835与所述第七电极层832间隔设置于所述第三表面805。所述第八电极层835覆盖部分所述第三表面805。所述第八电极层835在所述第二电介质层831的正投影,表征了所述第八电极层835的结构大小和形状。所述第八电极层835在所述第二电介质层831的正投影位于所述第六电极层833在所述第二电介质层831的投影中,形成第二结构电容807。也可以理解为,所述第八电极层835在所述第二电介质层831的正投影和所述第六电极层833在所述第二电介质层831的正投影部分重合。在重合部位,所述第八电极层835、所述第二电介质层831以及所述第六电极层833形成了所述第二结构电容807。
所述第八电极层835和所述第七电极层832分别设置在所述第六电极层833的两端。所述第六电极层833的两端分别与所述第八电极层835和所述第七电极层832形成了所述第二结构电容807和所述第四结构电容809。所述第六电极层833两端之间的部分形成传输线。所述第二结构电容807和所述第四结构电容809通过传输线串联连接,形成了两个电容串联连接的结构。因此,通过本申请所述第五磁场增强组件350,形成了所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808的三个电容串联的结构。
所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808之间相互配合,使得所述第五磁场增强组件350形成的增强器件,在MRI***的射频接收阶段达到最佳谐振频率。所述第五磁场增强组件350形成的增强器件与MRI***的工作频率相同时,可以增强检测部位的磁场,起到磁场增强作用。
在保证谐振频率相同的情况下,所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808串联连接,可以使得所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808采用电容值更大的电容,适用于高频MRI***。所述第二结构电容807、所述 第四结构电容809以及所述第三结构电容808采用电容值更大的电容,可以避免采用小电容。采用大电容值的电容会使得谐振频率波动较小,提高了谐振频率的稳定性,更加适合用于高场MRI***。
所述第五磁场增强组件350在磁场环境中会产生感应电压。所述第二结构电容807与所述第四结构电容809之间的所述第六电极层833会形成第一传输线。所述第三结构电容808与所述第四结构电容809之间的所述第七电极层832会形成第二传输线。多个所述第五磁场增强组件350形成增强器件时,所述第一传输线和所述第二传输线会形成寄生电容。寄生电容分别与所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808之间是并联关系。所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808串联连接,可以将感应电压分为多个,减小了所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808的分压。
进一步,所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808形成了串联的结构,降低了寄生电容上的电压。寄生电容上的电压减小,降低了寄生电容的危害,从而减小了负载效应。当多个所述第五磁场增强组件350形成增强器件加上负载之后,谐振频率不会有大幅度偏移,进而减小了所述第五磁场增强组件350的负载效应减小,使得谐振频率不容易受到受测物体的影响。谐振频率不容易受到受测物体的影响,可以提高所述第五磁场增强组件350的增强性能,增强了谐振频率的稳定性。
在一个实施例中,所述第七电极层832、所述第六电极层833、所述第五电极层834以及所述第八电极层835的材料可以为铜、银、金等无磁性金属。所述第二电介质层831的材料可以为耐燃材料等级为FR4的材料、聚亚苯基氧化物(PPE)等耐高温的热塑性树脂或者Rogers 4003C材料等。
在一个实施例中,所述第二电介质层831的宽度为15mm,厚度为0.51mm,长度为250mm。
在一个实施例中,由所述第三端881至所述第四端882的方向上,所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808对应的电极层的重合长度为30mm。
在一个实施例中,所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832的长度和所述第四结构电容809与所述第二结构电容807之间的所述第六电极层833的长度相同。
本实施例中,所述第三结构电容808和所述第二结构电容807关于所述第四结构电容809对称。有效磁场分布在所述第三结构电容808和所述第四结构电容809之间,以及所述第二结构电容807和所述第四结构电容809之间。有效磁场形成的区域作为检测区域,对检测部位进行检测。所述第三结构电容808和所述第四结构电容809之间的有效磁场形成第一检测区域。所述第二结构电容807和所述第四结构电容809之间的有效磁场形成第二检测区域。
所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832的长度和所述第四结构电容809与所述第二结构电容807之间的所述第六电极层833的长度相同。可以理解为, 第一检测区域与第二检测区域相同。也可以理解为,所述第二结构电容807和所述第三结构电容808关于所述第四结构电容809对称设置。也可以理解为,所述第二结构电容807靠近所述第三端881设置。所述第三结构电容808靠近所述第四端882设置。所述第四结构电容809设置于所述第三端881和所述第四端882连线的中部。所述第二结构电容807和所述第三结构电容808关于所述第四结构电容809对称设置,形成了均匀分布且对称的磁场,有利于MRI***的成像。
请参见图49,在一个实施例中,所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832的宽度小于所述第二电介质层831的宽度。
本实施例中,所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832之间会形成传输线,将所述第四结构电容809与所述第三结构电容808连接。电极层与电极层之间会形成杂散电容。所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832的宽度变小,会使得传输线的宽度变小。在不影响所述第四结构电容809与所述第三结构电容808连接的情况下,减小了杂散电容。
请参见图50,在一个实施例中,所述第四结构电容809与所述第二结构电容807之间的所述第六电极层833的宽度小于所述第二电介质层831的宽度。
本实施例中,所述第四结构电容809与所述第二结构电容807之间的所述第六电极层833会形成传输线,将所述第四结构电容809与所述第二结构电容807连接。电极层与电极层之间会形成杂散电容。所述第四结构电容809与所述第二结构电容807之间的所述第六电极层833的宽度变小,会使得传输线的宽度变小。在不影响所述第四结构电容809与所述第二结构电容807连接的情况下,减小了杂散电容。
在一个实施例中,垂直于所述第三端881至所述第四端882的方向上,所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832的宽度小于所述第四结构电容809对应的所述第七电极层832的宽度。所述第四结构电容809与所述第二结构电容807之间的所述第六电极层833的宽度小于所述第四结构电容809对应的所述第七电极层832的宽度。所述第四结构电容809对应的所述第七电极层832相比于结构电容之间的电极层的宽度大,有利于与所述第六电极层833形成有效的正对面积,进而形成所述第四结构电容809。
所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832的宽度小,且所述第四结构电容809与所述第二结构电容807之间的所述第六电极层833的宽度小,在不影响所述第四结构电容809与所述第三结构电容808连接的情况下,减小了杂散电容,进一步提高了MRI***的成像质量。
请参见图51,在一个实施例中,所述第七电极层832包括第一层111与第二层112。与图47所示的实施例相比,所述第一层111与所述第二层112间隔设置。所述第二层112靠近所述第四端882设置。所述第一层111靠近所述第二层112设置。
所述第一层111在所述第二电介质层831的正投影与所述第六电极层833在所述第二电介质 层831的正投影部分重叠,形成所述第四结构电容809。所述第五电极层834在所述第二电介质层831的正投影位于所述第二层112在所述第二电介质层831的正投影中,形成所述第三结构电容808。
所述第五磁场增强组件350还包括第一耗尽型MOS管231与第二耗尽型MOS管232。所述第一耗尽型MOS管231的源极与所述第一层111靠近所述第二层112的一端连接,所述第一耗尽型MOS管231的栅极和漏极连接。所述第二耗尽型MOS管232的栅极和漏极连接,并与所述第一耗尽型MOS管231的栅极和漏极连接。所述第二耗尽型MOS管232的源极与所述第二层112连接。
所述第一耗尽型MOS管231与所述第二耗尽型MOS管232反向串联连接,能够控制所述第一层111和所述第二层112在MRI***的射频发射阶段断开,且在MRI***的射频接收阶段连接。
所述第一耗尽型MOS管231与所述第二耗尽型MOS管232具有低压导通,高压截止的特性。并且,所述第一耗尽型MOS管231与所述第二耗尽型MOS管232,在室温下的夹断电压在1V左右,断开时间和恢复时间都在纳秒量级。
MRI***中射频发射阶段和射频接收阶段在时间顺序上有几十毫秒到几千毫秒的差别,可以快速实现所述第一耗尽型MOS管231与所述第二耗尽型MOS管232的导通和断开。MRI***的射频发射阶段和射频接收阶段的射频功率相差3个数量级。射频发射阶段线圈中的感应电压在几V到几百V之间,具体数值与所选的序列和翻转角有关。
所述第一耗尽型MOS管231与所述第二耗尽型MOS管232反向串联连接,能够控制所述第一层111和所述第二层112在射频发射阶段断开,且在射频接收阶段连接。在MRI***的射频发射阶段,通过所述第一耗尽型MOS管231与所述第二耗尽型MOS管232反向串联连接,可以适应于MRI***中的交流环境。无论如何变化,都能确保所述第一耗尽型MOS管231和所述第二耗尽型MOS管232中有一个发生截止,使得所述第一层111和所述第二层112断开,不连接。
在MRI***的射频发射阶段,感应电压较大,所述第一耗尽型MOS管231与所述第二耗尽型MOS管232处于断开状态,多个所述第五磁场增强组件350形成的磁场增强器处于断开状态,呈现失谐状态。所述第五磁场增强组件350中不存在电流,不产生会干扰射频的感应磁场,消除了磁场增强器对射频发射阶段磁场的影响。
在MRI***的射频接收阶段,所述第一耗尽型MOS管231与所述第二耗尽型MOS管232导通,进而确保所述第一层111和所述第二层112连接。多个所述第五磁场增强组件350形成的磁场增强器处于连接状态,能够呈现谐振状态,大幅度增强信号场,增强图像信噪比。
因此,通过所述第一耗尽型MOS管231和所述第二耗尽型MOS管232控制所述第一层111和所述第二层112在MRI***的射频发射阶段断开,在射频接收阶段连接。通过所述第一耗尽 型MOS管231和所述第二耗尽型MOS管232能够使得所述第五磁场增强组件350只能增强射频接收场,不会对射频发射场进行增强,提高了图像信噪比。
所述第五磁场增强组件350通过所述第一耗尽型MOS管231与所述第二耗尽型MOS管232,引入非线性控制结构,使得多个所述第五磁场增强组件350形成的磁场增强器也具有非线性响应特性,能够适用于包括快速自旋回波序列在内的所有临床序列。
请参见图52,在一个实施例中,所述第五磁场增强组件350还包括第三二极管451、第四二极管452、第二外接电容442以及第三外接电容443。所述第三二极管451的阳极与所述第三结构电容808对应的所述第七电极层832电连接。所述第四二极管452的阴极与所述第三结构电容808对应的所述第七电极层832电连接。所述第三外接电容443的一端与所述第五电极层834电连接。所述第三外接电容443的另一端分别与所述第三二极管451的阴极、所述第四二极管452的阳极和所述第二外接电容442一端电连接。所述第二外接电容442的另一端与所述第三结构电容808对应的所述第七电极层832电连接。
MRI***的射频发射阶段和射频接收阶段在时间顺序上有几十到几千毫秒的差别。射频发射阶段和射频接收阶段的射频功率相差3个数量级。MRI***的射频发射阶段结构电容上的电压在几伏到几百伏之间。而在射频接收阶段,所述结构电容两端的电压在毫伏级别。
所述第三二极管451与所述第四二极管452的开启电压可以大于1伏。即当所述第七电极层832和所述第五电极层834两端的压差大于1伏时,所述第三二极管451或所述第四二极管452导通。当所述第七电极层832和所述第五电极层834两端的压差小于1伏时,所述第三二极管451和所述第四二极管452断开。
可以理解,所述第三二极管451和所述第四二极管452的导通电压可以在0伏到1伏。在一个实施例中,所述第三二极管451和所述第四二极管452的导通电压可以为0.8V。所述第三二极管451和所述第四二极管452分别串联在所述第七电极层832和所述第五电极层834之间。所述第三二极管451和所述第四二极管452反接。
由于MRI***的射频交流特性,所述第七电极层832和所述第五电极层834产生的感应电压也是交流电压。在射频发射阶段,由于所述第七电极层832和所述第五电极层834之间的电压差已经超过所述第三二极管451和所述第四二极管452的导通电压。因此,无论所述第七电极层832和所述第五电极层834哪个的电压高,所述第三二极管451和所述第四二极管452总有一个处于导通状态。因此,所述第二外接电容442被短路。只有所述第三外接电容443连接在所述第七电极层832和所述第五电极层834之间。通过调控所述第三外接电容443的电容值可以降低或避免所述第五磁场增强组件350所在的回路在射频发射阶段的失谐程度。
通过所述第三外接电容443能够在使用所述第五磁场增强组件350时和使用所述第五磁场增强组件350前,磁共振***中的受测区域磁场强度相同。所述第一筒形磁场增强器810或者所述第二筒形磁场增强器820采用所述第五磁场增强组件350时,可以消除磁场增强器对射频发射阶 段的影响,使得磁场增强器能够适用于所有的临床序列,提高了磁场增强器的临床实用性。
而在MRI***的射频接收阶段,由于所述第七电极层832和所述第五电极层834之间的电压差小于所述第三二极管451和所述第四二极管452的导通电压。因此,无论所述第七电极层832和所述第五电极层834哪个的电压高,所述第三二极管451和所述第四二极管452均处于不导通的状态。在MRI***的射频接收的阶段,所述第二外接电容442和所述第三外接电容443串联于所述第七电极层832和所述第五电极层834之间。
请参见图53,在一个实施例中,与图51所示的实施例相比,所述第五磁场增强组件350还包括第一电感241、第三二极管213以及第四二极管214。所述第三电容223的一端与所述第一层111靠近所述第二层112的一端连接。所述第三电容223的另一端与所述第二层112远离所述第四端882的一端连接。所述第一电感241的一端与所述第一层111靠近所述第二层112的一端连接。所述第一电感241的另一端分别与所述第三二极管213的阴极和所述第四二极管214的阳极连接。所述第三二极管213的阳极和所述第四二极管214的阴极与所述第二层112远离所述第四端882的一端连接。
在MRI***中,以在射频接收阶段增强人体反馈信号的磁场强度。在MRI***的射频发射阶段,发射阶段的磁场能量是接收阶段的磁场能量的1000倍以上。发射阶段感应电压在几十伏到几百伏之间。接收阶段感应电压小于1V。
所述第三二极管213和所述第四二极管214反向并联连接。在MRI***的射频发射阶段,射频线圈发射射频发射信号,磁场的场强较大。所述第五磁场增强组件350产生的感应电压较大。加载在所述第三二极管213和所述第四二极管214两端的电压正反交替。加载的电压超过所述第三二极管213和所述第四二极管214的开启电压,所述第三二极管213和所述第四二极管214导通。所述第三电容223与所述第一电感241并联,发生并联谐振,使得第一电感241、第三二极管213、第四二极管214以及所述第三电容223形成的电路处于高阻状态。MRI***的射频发射阶段,所述第三结构电容808和所述第四结构电容809之间几乎没有电流流通。所述第五磁场增强组件350产生的磁场减弱,进而减小所述第五磁场增强组件350对射频发射阶段磁场的影响,从而减小检测图像的伪影,提高检测图像的清晰度。
在MRI***的射频接收阶段,检测部位发射反馈信号,磁场的场强较小。所述第五磁场增强组件350产生的感应电压较小。加载的电压不能达到所述第三二极管213和所述第四二极管214的开启电压,所述第三二极管213和所述第四二极管214不导通。所述第三结构电容808和所述第四结构电容809之间通过所述第三电容223连接,有电流通过。多个所述第五磁场增强组件350组成的磁场增强器处于谐振状态,起到增强磁场的作用。
请参见图54与图55,在一个实施例中,所述第六磁场增强组件360包括第二电介质层831、第七电极层832、第六电极层833、第五电极层834、第八电极层835、第一电极连接层123、第九电极层836。
与图47所示实施例相比,所述第二电介质层831的中部设置有第二过孔220。所述第七电极层832设置于所述第三表面805。所述第七电极层832覆盖部分所述第三表面805。所述第七电极层832靠近所述第四端882设置。所述第六电极层833设置于所述第四表面806。所述第六电极层833覆盖部分所述第四表面806。所述第六电极层833靠近所述第二电介质层831的中部设置。所述第七电极层832在所述第二电介质层831的正投影与所述第六电极层833在所述第二电介质层831的正投影部分重叠以形成第四结构电容809。所述第四结构电容809靠近所述第二电介质层831的中部设置。
所述第五电极层834设置于所述第四表面806。所述第五电极层834覆盖部分所述第四表面806。所述第五电极层834靠近所述第四端882设置。所述第五电极层834与所述第六电极层833间隔设置。所述第五电极层834在所述第二电介质层831的正投影位于所述第七电极层832在所述第二电介质层831的正投影中,形成第三结构电容808。所述第八电极层835设置于所述第三表面805。所述第八电极层835覆盖部分所述第三表面805。所述第八电极层835靠近所述第三端881设置。所述第八电极层835与所述第七电极层832间隔设置。
所述第一电极连接层123设置于所述第二过孔220。所述第一电极连接层123分别延伸至所述第三表面805与所述第四表面806。所述第一电极连接层123的两端分别与所述第六电极层833和所述第八电极层835连接。所述第九电极层836与所述第六电极层833间隔设置于所述第四表面806。所述第九电极层836覆盖部分所述第四表面806。所述第九电极层836靠近所述第三端881设置。所述第九电极层836在所述第二电介质层831的正投影位于所述第八电极层835在所述第二电介质层831的正投影中,形成第二结构电容807。
所述第九电极层836在所述第二电介质层831的正投影,表征了所述第九电极层836的结构大小和形状。所述第九电极层836在所述第二电介质层831的正投影和所述第八电极层835在所述第二电介质层831的正投影的一部分进行重合。在重合部位,所述第九电极层836、所述第二电介质层831以及所述第八电极层835形成所述第二结构电容807。
所述第二结构电容807与所述第四结构电容809之间的所述第八电极层835和所述第一电极连接层123形成传输线。所述第二结构电容807与所述第四结构电容809通过传输线串联连接。所述第四结构电容809与所述第三结构电容808之间的所述第七电极层832形成传输线。所述第四结构电容809与所述第三结构电容808通过传输线串联连接。
因此,通过本实施例中的所述第六磁场增强组件360,形成了所述第二结构电容807、所述第四结构电容809以及所述第三结构电容808的三个电容串联的结构。
通过所述第二过孔220和所述第一电极连接层123将不同表面的所述第六电极层833与所述第八电极层835连接,使得所述第二结构电容807与所述第四结构电容809串联连接。当对多个所述第六磁场增强组件360进行组合形成磁场增强器时,可以同侧连接所述第九电极层836和所述第五电极层834。
所述第八电极层835与所述第七电极层832之间形成有空隙,并露出所述第三表面805。所述第一电极连接层123的两端分别延伸至所述第三表面805和所述第四表面806,并将不同表面的所述第六电极层833与所述第八电极层835连接。所述第四结构电容809与所述第二结构电容807之间的所述第八电极层835与所述第一电极连接层123形成的传输线,将所述空隙对应的空间进行了补充,使得所述空隙对应的空间也具有磁场形成。所述空隙对应的空间具有磁场形成,不会出现有某一部分不存在磁场的情况。所述第一电极连接层123的两端分别延伸至所述第三表面805和所述第四表面806。所述第一电极连接层123将不同表面的所述第六电极层833与所述第八电极层835连接,使得磁场分布更加均匀,提高了MRI***的成像质量。
在一个实施例中,所述第二过孔220靠近所述第二电介质层831的中部设置。且所述第二过孔220的直径小于所述第二电介质层831的宽度。
本实施例中,所述第一电极连接层123穿过所述第二过孔220分别连接所述第八电极层835和所述第六电极层833。所述第六电极层833与所述第七电极层832正对设置,形成所述第四结构电容809。所述第二过孔220靠近所述第二电介质层831的中部设置,使得所述第四结构电容809也靠近所述第二电介质层831的中部设置,提高了磁场的均匀对称性。
所述第二过孔220的直径小于所述第二电介质层831第二电介质层831的宽度,减少了所述第二过孔220中所述第一电极连接层123的面积,进而减少了所述第一电极连接层123形成的杂散电容。
在一个实施例中,所述第八电极层835、所述第一电极连接层123以及所述第六电极层833一体成型。
请参见图56,在一个实施例中,所述第六磁场增强组件360还包括第一外接电容440、第一二极管431以及第二二极管432。所述第一外接电容440的两端分别与所述第七电极层832和所述第五电极层834电连接。所述第一二极管431的阳极与所述第七电极层832电连接。所述第一二极管431的阴极与所述第五电极层834电连接。所述第二二极管432的阴极与所述第七电极层832电连接。所述第二二极管432的阳极与所述第五电极层834电连接。
可以理解,所述第一二极管431和所述第二二极管432的导通电压可以在0伏到1伏。在一个实施例中,所述第一二极管431和所述第二二极管432的导通电压可以为0.8V。所述第一二极管431和所述第二二极管432并联在所述第七电极层832和所述第五电极层834之间。所述第一二极管431和所述第二二极管432反接。
由于MRI***的射频交流特性,所述第七电极层832和所述第六电极层833产生的感应电压也是交流电压。在MRI***的射频发射阶段,由于所述第七电极层832和所述第五电极层834之间的电压差已经超过所述第一二极管431和所述第二二极管432的导通电压。因此,无论所述第七电极层832和所述第五电极层834哪个的电压高,所述第一二极管431和所述第二二极管432总有一个处于导通状态。因此,将所述第七电极层832和所述第五电极层834电连接。所述 第三结构电容808被短路。所述第六磁场增强组件360形成的磁场增强器处于失谐状态。
而在MRI***的射频接收阶段,由于所述第七电极层832和所述第五电极层834之间的电压差小于所述第一二极管431和所述第二二极管432的导通电压。因此,无论所述第七电极层832和所述第五电极层834哪个的电压高,所述第一二极管431和所述第二二极管432均处于不导通的状态。所述第六磁场增强组件360形成的磁场增强器处于谐振状态。
在一个实施例中,上述实施例中的元件电容可以为固定电容,也可以为调节电容。当MRI***的射频线圈的频率确定后,元件电容可以选择固定电容,使得所述固定电容与其他结构电容和元件电容配合,使磁场增强组件所在回路的谐振频率与MRI***的射频线圈的频率相等,进而起到增强磁场的作用。当MRI***的射频线圈的频率不确定时,元件电容可以采用可调电容。通过调节可调电容,调节谐振频率,以使得磁场增强组件适用不同的工作环境。
在一个实施例中,所述第二筒形磁场增强器820的直径为100mm。所述第二筒形磁场增强器820包括多个所述第一磁场增强组件310或者所述第二磁场增强组件320或者所述第三磁场增强组件330。所述第一电极层110与所述第二电极层120的传输线宽度为4mm。所述第一电介质层100的宽度为15mm。所述第一电容405设置于中间位置,电容值为40pF。所述第一电介质层100的长度为250mm。所述第一电介质层100的材料选用Rogers 4003C,厚度为0.51mm。所述第二筒形磁场增强器820的谐振频率为52MHz,与主磁场强度为3T时的核磁共振成像***的工作频率对应。所述第二筒形磁场增强器820用于增强 31P的非氢质子核的核磁信号。
所述第一筒形磁场增强器810的直径为120mm。所述第一筒形磁场增强器810包括多个所述第四磁场增强组件340。所述第二结构电容807与所述第三结构电容808之间的所述第七电极层832的传输线宽度为4mm。所述第二电介质层831的宽度为15mm。所述第二结构电容807与所述第三结构电容808位于所述第四磁场增强组件340的两端。所述第二结构电容807与所述第三结构电容808对应的电极重合部位的长度为15mm或者14.8mm。所述第二电介质层831的材料选用Rogers 4003C,厚度为0.51mm。所述第二电介质层831的长度为250mm。所述第一筒形磁场增强器810的谐振频率为128MHz,与主磁场强度为3T时的核磁共振成像***的工作频率对应。所述第一筒形磁场增强器810用于增强 1H的氢质子核的核磁信号。
请参见图57,本申请所述双核磁场增强装置30采用上述实施例中所述第二筒形磁场增强器820与所述第一筒形磁场增强器810,具有两个谐振峰,谐振频率分别为51.6MHz和128.8MHz。因此,所述双核磁场增强装置30能够同时增强 31P和 1H的信号场,可以检测相同部位的不同目标核,可以显示出所述检测部位的不同目标核对应的MRI成像信息。
在一个实施例中,本申请提供一种磁共振***,包括上述实施例中任一实施例所述的双核磁场增强装置30。
以上所述实施例的各技术特征可以进行任意的组合,为使描述简洁,未对上述实施例中的各个技术特征所有可能的组合都进行描述,然而,只要这些技术特征的组合不存在矛盾,都应当认 为是本说明书记载的范围。
以上所述实施例仅表达了本申请的几种实施方式,其描述较为具体和详细,但并不能因此而理解为对本申请专利范围的限制。应当指出的是,对于本领域的普通技术人员来说,在不脱离本申请构思的前提下,还可以做出若干变形和改进,这些都属于本申请的保护范围。因此,本申请专利的保护范围应以所附权利要求为准。
最后,还需要说明的是,在本文中,诸如第一和第二等之类的关系术语仅仅用来将一个实体或者操作与另一个实体或操作区分开来,而不一定要求或者暗示这些实体或操作之间存在任何这种实际的关系或者顺序。而且,术语“包括”、“包含”或者其任何其他变体意在涵盖非排他性的包含,从而使得包括一系列要素的过程、方法、物品或者设备不仅包括那些要素,而且还包括没有明确列出的其他要素,或者是还包括为这种过程、方法、物品或者设备所固有的要素。在没有更多限制的情况下,由语句“包括一个……”限定的要素,并不排除在包括所述要素的过程、方法、物品或者设备中还存在另外的相同要素。
本说明书中各个实施例采用递进的方式描述,每个实施例重点说明的都是与其他实施例的不同之处,各个实施例之间相同相似部分互相参见即可。
对所提供的实施例的上述说明,使本领域专业技术人员能够实现或使用本申请。对这些实施例的多种修改对本领域的专业技术人员来说将是显而易见的,本文中所定义的一般原理可以在不脱离本申请的精神或范围的情况下,在其它实施例中实现。因此,本申请将不会被限制于本文所示的这些实施例,而是要符合与本文所提供的原理和新颖特点相一致的最宽的范围。

Claims (20)

  1. 一种双核磁场增强装置,其特征在于,包括:
    第一筒形磁场增强器(810),包围形成第一容纳空间(819),所述第一筒形磁场增强器(810)用于增强检测部位的氢质子核的核磁信号;
    第二筒形磁场增强器(820),设置于所述第一容纳空间(819)内,用于增强所述检测部位的非氢质子核的核磁信号,所述第二筒形磁场增强器(820)包围形成第二容纳空间(829),用于容纳检测部位。
  2. 如权利要求1所述的双核磁场增强装置,其特征在于,所述第一筒形磁场增强器(810)包括:
    第一筒形支架(811),具有第一外表面(801)与第一内表面(802),所述第一外表面(801)环绕所述第一内表面(802),并且与所述第一内表面(802)间隔相对设置,所述第一内表面(802)包围所述第一容纳空间(819);
    多个外磁场增强组件(812),所述外磁场增强组件(812)的延伸方向与所述第一筒形支架(811)的第一中心轴线的延伸方向相同,并环绕所述第一筒形支架(811)的第一中心轴线间隔设置于所述第一外表面(801);
    每个所述外磁场增强组件(812)具有相对设置的第一端和第二端,所述多个外磁场增强组件(812)的第一端依次连接,所述多个外磁场增强组件(812)的第二端依次连接。
  3. 如权利要求2所述的双核磁场增强装置,其特征在于,还包括:
    多个第一谐振控制电路(851),一个所述第一谐振控制电路(851)与一个所述外磁场增强组件(812)电连接,用于控制所述外磁场增强组件(812)的工作状态。
  4. 如权利要求2所述的双核磁场增强装置,其特征在于,所述第二筒形磁场增强器(820)包括:
    第二筒形支架(821),设置于所述第一容纳空间(819)内,所述第二筒形支架(821)具有第二外表面(803),与所述第一内表面(802)间隔相对设置;
    多个内磁场增强组件(822),间隔设置于所述第二外表面(803),所述内磁场增强组件(822)的延伸方向与所述第二筒形支架(821)的第二中心轴线的延伸方向相同;
    每个所述内磁场增强组件(822)具有相对设置的第一端和第二端,所述多个内磁场增强组件(822)的第一端依次连接,所述多个内磁场增强组件(822)的第二端依次连接。
  5. 如权利要求4所述的双核磁场增强装置,其特征在于,还包括:
    多个第二谐振控制电路(852),一个所述第二谐振控制电路(852)与一个所述内磁场增强组件(822)电连接,用于控制所述内磁场增强组件(822)的工作状态。
  6. 如权利要求4所述的双核磁场增强装置,其特征在于,所述内磁场增强组件(822)包括:
    第一电介质层(100),包括间隔相对的第一表面(101)和第二表面(102),所述第一电介质层(100)具有相对的第一端(103)与第二端(104);
    第一电极层(110),设置于所述第一表面(101),并覆盖部分所述第一表面(101),且靠近所述第二端(104)设置;
    第二电极层(120),设置于所述第一表面(101),与所述第一电极层(110)间隔设置,并覆盖部分所述第一表面(101),且靠近所述第一端(103)设置;以及
    第一外接电容(405),所述第一外接电容(405)的一端与所述第二电极层(120)远离所述第一端(103)的一端连接,所述第一外接电容(405)的另一端与所述第一电极层(110)远离所述第二端(104)的一端连接,且所述第一外接电容(405)靠近所述第一电介质层(100)的中部设置。
  7. 如权利要求6所述的双核磁场增强装置,其特征在于,所述外磁场增强组件(812)包括:
    第二电介质层(831),具有间隔相对的第三表面(805)与第四表面(806),所述第二电介质层(831)具有相对的第三端(881)与第四端(882);
    第七电极层(832),设置于所述第三表面(805),并覆盖所述第三表面(805);
    第六电极层(833),设置于所述第四表面(806),并覆盖部分所述第四表面(806),且所述第六电极层(833)靠近所述第三端(881)设置;
    第五电极层(834),与所述第六电极层(833)间隔设置于所述第四表面(806),并覆盖部分所述第四表面(806),且所述第五电极层(834)靠近所述第四端(882)设置;
    所述第六电极层(833)在所述第二电介质层(831)的正投影,位于所述第七电极层(832)在所述第二电介质层(831)的正投影中,形成第二结构电容(807);
    所述第五电极层(834)在所述第二电介质层(831)的正投影,位于所述第七电极层(832)在所述第二电介质层(831)的正投影中,形成第三结构电容(808)。
  8. 如权利要求7所述的双核磁场增强装置,其特征在于,沿环绕所述第一筒形支架(811)的第一中心轴线的方向,所述第二结构电容(807)和所述第三结构电容(808)之间的所述第七电极层(832)的宽度小于所述第二结构电容(807)和所述第三结构电容(808)对应的所述第七电极层(832)的宽度。
  9. 如权利要求1所述的双核磁场增强装置,其特征在于,所述第一筒形磁场增强器(810)的第一中心轴线与所述第二筒形磁场增强器(820)的第二中心轴线重合,且所述第一筒形磁场增强器(810)的中截面与所述第二筒形磁场增强器(820)的中截面重合。
  10. 如权利要求9所述的双核磁场增强装置,其特征在于,沿着所述第一中心轴线方向,所述第一筒形磁场增强器(810)的长度小于所述第二筒形磁场增强器(820)的长度,且所述第一筒形磁场增强器(810)的两端与所述第二筒形磁场增强器(820)的两端不共面。
  11. 一种双核磁场增强装置,其特征在于,包括:
    第一筒形磁场增强器(810)包括:
    第一筒形支架(811),具有第一外表面(801)与第一内表面(802),所述第一外表面(801)环绕所述第一内表面(802),并且与所述第一内表面(802)间隔相对设置,所述第一内表面(802)包围形成第一容纳空间(819);
    多个外磁场增强组件(812),所述外磁场增强组件(812)的延伸方向与所述第一筒形支架(811)的第一中心轴线的延伸方向相同,并环绕所述第一中心轴线间隔设置于所述第一外表面(801);以及
    第一环形导电片(861)和第二环形导电片(862),分别设置于所述第一筒形支架(811)相对的两端,并环绕所述第一中心轴线设置,所述第一环形导电片(861)的两端的连接处具有第一相位调控缺口(871),所述第二环形导电片(862)的两端的连接处具有第二相位调控缺口(872);
    每个所述外磁场增强组件(812)的两端分别与所述第一环形导电片(861)和所述第二环形导电片(862)连接,用于增强检测部位的氢质子核的核磁信号;
    第二筒形磁场增强器(820),设置于所述第一容纳空间(819)内,所述第二筒形磁场增强器(820)包围形成第二容纳空间(829),用于容纳检测部位,所述第二筒形磁场增强器(820)用于增强所述检测部位的非氢质子核的核磁信号。
  12. 如权利要求11所述的双核磁场增强装置,其特征在于,所述第一相位调控缺口(871)与所述第二相位调控缺口(872)相对设置,且所述第一相位调控缺口(871)与所述第二相位调控缺口(872)的连线与所述第一中心轴线平行。
  13. 如权利要求12所述的双核磁场增强装置,其特征在于,所述多个外磁场增强组件(812)设置于所述第一相位调控缺口(871)和所述第二相位调控缺口(872)的连线的两侧。
  14. 如权利要求11所述的双核磁场增强装置,其特征在于,所述第一相位调控缺口(871)与所述第二相位调控缺口(872)的弧长,等于相邻两个所述外磁场增强组件(812)之间的间隔距离。
  15. 如权利要求11所述的双核磁场增强装置,其特征在于,所述第二筒形磁场增强器(820)包括:
    第二筒形支架(821),设置于所述第一容纳空间(819)内,所述第二筒形支架(821)具有第二外表面(803),与所述第一内表面(802)间隔相对设置;
    多个内磁场增强组件(822),间隔设置于所述第二外表面(803),所述内磁场增强组件(822)的延伸方向与所述第二筒形支架(821)的第二中心轴线的延伸方向相同;
    第三环形导电片(866)和第四环形导电片(867),分别设置于所述第二筒形支架(821)相对的两端,并环绕所述第二筒形支架(821)的中心轴线设置,所述第三环形导电片(866)的两端的连接处具有第三相位调控缺口(873),所述第四环形导电片(867)的两端的连接处具有第四相位调控缺口(874);
    每个所述内磁场增强组件(822)的两端分别与所述第三环形导电片(866)和所述第四环形导电片(867)连接,用于增强所述检测部位的非氢质子核的核磁信号。
  16. 如权利要求15所述的双核磁场增强装置,其特征在于,所述第三相位调控缺口(873)与所述第四相位调控缺口(874)相对设置,且所述第三相位调控缺口(873)与所述第四相位调控缺口(874)的连线与所述第二中心轴线平行。
  17. 如权利要求16所述的双核磁场增强装置,其特征在于,所述多个内磁场增强组件(822)设置于所述第三相位调控缺口(873)与所述第四相位调控缺口(874)的连线的两侧。
  18. 如权利要求16所述的双核磁场增强装置,其特征在于,所述第三相位调控缺口(873)与所述第一相位调控缺口(871)正交设置,所述第四相位调控缺口(874)与所述第二相位调控缺口(872)正交设置。
  19. 如权利要求18所述的双核磁场增强装置,其特征在于,围绕所述第一中心轴线的方向,所述第一相位调控缺口(871)与所述第二相位调控缺口(872)的弧长相等;
    围绕所述第二中心轴线的方向,所述第三相位调控缺口(873)与所述第四相位调控缺口(874)的弧长相等。
  20. 一种磁共振***,其特征在于,包括权利要求1-19任一项所述的双核磁场增强装置。
PCT/CN2021/114228 2021-02-10 2021-08-24 一种双核mri的图像增强超构表面器件 WO2022170753A1 (zh)

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Publication number Priority date Publication date Assignee Title
CN101726714A (zh) * 2008-10-23 2010-06-09 通用电气公司 用于多核mri/mrs的混合式鸟笼型-tem射频(rf)线圈
CN103116147A (zh) * 2013-02-26 2013-05-22 江苏美时医疗技术有限公司 一种用于磁共振成像***的膝盖射频线圈
JP2016178967A (ja) * 2015-03-23 2016-10-13 株式会社日立製作所 磁気共鳴イメージング装置
CN106980097A (zh) * 2017-05-19 2017-07-25 深圳市特深电气有限公司 用于磁共振成像***的鸟笼线圈及其调谐方法
CN111722166A (zh) * 2019-12-12 2020-09-29 杭州拉莫科技有限公司 一种用于超高场磁共振成像***的啮齿类小动物成像装置

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101726714A (zh) * 2008-10-23 2010-06-09 通用电气公司 用于多核mri/mrs的混合式鸟笼型-tem射频(rf)线圈
CN103116147A (zh) * 2013-02-26 2013-05-22 江苏美时医疗技术有限公司 一种用于磁共振成像***的膝盖射频线圈
JP2016178967A (ja) * 2015-03-23 2016-10-13 株式会社日立製作所 磁気共鳴イメージング装置
CN106980097A (zh) * 2017-05-19 2017-07-25 深圳市特深电气有限公司 用于磁共振成像***的鸟笼线圈及其调谐方法
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