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公开(公告)号：US5387868A
公开(公告)日：1995-02-07
申请号：US116387
申请日：1993-09-02
CPC分类号： G01R33/3621 , G01R33/3671 , G01R33/58
摘要： In magnetic resonance apparatus in a magnet system (1) for generating a steady magnetic field, a coil system (3) for generating gradient fields, and at least one RF coil (9) which is tuned to a predetermined frequency and connected to first and second input terminals (53, 55) of an input amplifier circuit (43) of a receiving device (13) for RF order to enable simulation of the loading of the RF coil (9) by a patient during installation and testing of the operation of the apparatus without utilizing a load phantom, the circuit formed by the RF coil (9) and the input amplifier circuit (43) comprises a load network (61 ). In one embodiments first and second input terminals (53, 55) of the input amplifier circuit (43) are interconnected via the load network (61) which comprises a series connection of a switch (63) and a resistor (65). The switch is preferably formed by a diode (63), one electrode of which is connected to one of the input terminals (53) of the input amplifier circuit (43), its other electrode being connected to one end of the resistor (65), the other end of which is connected to the other input terminal (55) via a capacitor (73). The junction point of the resistor (65) and the capacitor (73) is connected to a control terminal (71) whereto a positive or a negative direct voltage, relative to the first input terminal (53), can be applied as desired in order to set the diode (63) to a conductive state or a blocked state.
摘要翻译： 在用于产生稳定磁场的磁体系统（1）的磁共振装置中，用于产生梯度场的线圈系统（3）和至少一个调谐到预定频率并连接到第一和第 用于RF命令的接收装置（13）的输入放大器电路（43）的第二输入端子（53,55），以便在安装和测试操作期间由患者模拟RF线圈（9）的负载 该装置不使用负载体模，由RF线圈（9）和输入放大器电路（43）形成的电路包括负载网络（61）。 在一个实施例中，输入放大器电路（43）的第一和第二输入端子（53,55）经由负载网络（61）互连，负载网络（61）包括开关（63）和电阻器（65）的串联连接。 开关优选地由二极管（63）形成，二极管（63）的一个电极连接到输入放大器电路（43）的一个输入端子（53），其另一个电极连接到电阻器（65）的一端， ，其另一端经由电容器（73）与另一方的输入端子（55）连接。 电阻器65和电容器73的接点连接到控制端子71，在控制端子71上可以根据需要依次施加相对于第一输入端子（53）的正或负直流电压 以将二极管（63）设置为导通状态或阻塞状态。
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2.发明授权Magnetic resonance imaging apparatus comprising a pin diode uncoupled detection coil 失效磁共振成像装置，包括一个pin二极管脱耦检测线圈
公开(公告)号：US4810968A
公开(公告)日：1989-03-07
申请号：US58419
申请日：1987-06-05
IPC分类号： G01R33/20 , A61B5/055 , A61B10/00 , G01R33/36 , G01R33/38 , G01R33/385 , H01F7/20 , G01R33/22
CPC分类号： G01R33/3657 , G01R33/3621
摘要： In a magnetic resonance imaging apparatus comprising a surface coil, the circuit in which the surface coil is included is interrupted by means of a PIN diode in the non-active state of the coil. In addition to the PIN diode in the resonant circuit of the surface coil, PIN diodes are included in all supply leads of the resonant circuit. An advantage thereof consists in that no RF currents will flow in the supply leads and that the induction voltages generated in the surface coil in the active state of the transmitter coil of the device are actually rectified by the diodes and themselves form a blocking voltage for the PIN diodes included in the circuit. As a result, the biasing of the PIN diodes is increased, so that they remain blocked.
摘要翻译： 在包括表面线圈的磁共振成像设备中，包括表面线圈的电路通过线圈非活动状态下的PIN二极管中断。 除了表面线圈的谐振电路中的PIN二极管之外，PIN二极管被包括在谐振电路的所有电源引线中。 其优点在于，在电源线中不会流过RF电流，并且在器件的发射器线圈的有效状态下在表面线圈中产生的感应电压实际上由二极管整流，并且它们本身形成用于 PIN二极管包含在电路中。 结果，PIN二极管的偏置增加，使得它们保持阻塞。
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公开(公告)号：US4788503A
公开(公告)日：1988-11-29
申请号：US59283
申请日：1987-06-08
CPC分类号： G01R33/3657 , G01R33/3628
摘要： In magnetic resonance imaging apparatus in which bird-cage coils are used in combination with other coils, a capacitance is bridged by means of an inductive element. Substantial detuning and hence adequate uncoupling of the bird-cage coil from the other (receiving) coil is achieved. Use can be made of the already present coaxial transmission line via which the RF energy is applied to the bird-cage coil. Connecting the core and the jacket of the coaxial transmission line there is arranged a diode switch so that the bird-cage coil circuit can be electronically detuned, thus enabling fast switching on and off of the bird-cage coil.
摘要翻译： 在其中将鸟笼线圈与其它线圈组合使用的磁共振成像装置中，通过感应元件桥接电容。 实现了明显的失谐，从而使鸟笼线圈与其他（接收）线圈的充分解耦。 可以使用已经存在的同轴传输线，其中RF能量被施加到鸟笼线圈。 连接同轴传输线的芯和外壳设置二极管开关，使鸟笼线圈电路可以电子失谐，从而实现鸟笼线圈的快速接通和断开。
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公开(公告)号：US5861749A
公开(公告)日：1999-01-19
申请号：US768478
申请日：1996-12-18
CPC分类号： G01R33/3415 , G01R33/3621
摘要： Magnetic resonance apparatus includes an RF measuring coil system (12) for detection of magnetic resonance signals to be generated in an object to be examined, which measuring coil system includes an at least one-dimensional array (33) of contiguous surface coils (33a, . . . 33f) and means for decoupling the surface coils from one another, and a signal processing circuit (15) which is connected to the surface coils and includes a number of processing channels (49a, 49b, 49c) for processing RF signals generated by the surface coils. Between the surface coils (33a, . . . ,) and the signal processing circuit (15) there is arranged a combination circuit (13) which includes at least two adder units (45a, 45b, 45c), each adder unit having at least two inputs and one output (47a, 47b, 47c) and being arranged to add signals, presented to its input, with a predetermined mutual phase shift, and to make the signal resulting from the addition available on the output. Each input of the adder unit (45a, . . . ) is connected to one of the surface coils (33a, . . . ) and the surface coils connected to the inputs of one and the same adder unit constitute a contiguous part of the array (33). The output of each adder unit (45a, . . . ) is connected to one of the processing channels (49a, . . . ) of the signal processing circuit (15). As a result of these steps, the number of processing channels (49a, . . . ) can be substantially smaller than the number of surface coils (33a, . . . ). Consequently, the construction of the signal processing circuit (15) is comparatively simple and inexpensive.
摘要翻译： 磁共振装置包括用于检测待检测物体中产生的磁共振信号的RF测量线圈系统（12），所述测量线圈系统包括连续表面线圈（33a，33a）的至少一维阵列（33） 以及用于将表面线圈彼此去耦的装置和连接到表面线圈并包括用于处理产生的RF信号的多个处理通道（49a，49b，49c）的信号处理电路（15） 通过表面线圈。 在表面线圈（33a，...）和信号处理电路（15）之间布置有包括至少两个加法器单元（45a，45b，45c）的组合电路（13），每个加法器单元至少具有 两个输入和一个输出（47a，47b，47c），并且被布置成以预定的相位相移添加呈现给其输入的信号，并且使得在输出上可用的加法产生的信号。 加法器单元（45a ...）的每个输入端连接到一个表面线圈（33a ...），并且连接到同一加法器单元的输入端的表面线圈构成阵列的连续部分 （33）。 每个加法器单元（45a ...）的输出连接到信号处理电路（15）的一个处理通道（49a ...）。 作为这些步骤的结果，处理通道（49a ...）的数量可以显着小于表面线圈（33a ...）的数量。 因此，信号处理电路（15）的构造相对简单且便宜。
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5.发明授权
公开(公告)号：US5285160A
公开(公告)日：1994-02-08
申请号：US926575
申请日：1992-08-06
CPC分类号： G01R33/3415 , G01R33/28 , G01R33/34007 , G01R33/3678
摘要： Magnetic resonance apparatus includes a main magnet system (1) for generating a steady magnetic field, a magnet system (3) for generating gradient fields, an RF transmitter coil (9) and an RF receiver coil system (13) which includes first and second RF coil systems (47, 49) for detecting resonance signals generated in respective first and second regions of an object to be arranged on a supporting face (43), said regions being adjacently situated in a first direction (57), each of the first and second RF coil systems comprising at least a surface coil. The apparatus is intended notably for the examination of the spine of a patient arranged on the supporting face (43), the first region containing the thoracic segment of the spine (T-spine) and the second region containing the lumbar segment (L-spine). In order to enable easy adaptation of the position of the second RF coil system (49) to the location of the L-spine of an individual patient, the first RF coil system (47) is arranged to be stationary relative to the supporting face (43) in a first coil plane (53) extending substantially parallel to the supporting face, whereas the second RF coil system (49) is arranged to as to be displaceable in the first direction (57) in a second coil plane (61) which extends parallel to the first coil plane (53).
摘要翻译： 磁共振装置包括用于产生稳定磁场的主磁体系统（1），用于产生梯度场的磁体系统（3），RF发射器线圈（9）和RF接收器线圈系统（13），其包括第一和第二 用于检测在要布置在支撑面（43）上的物体的各自的第一和第二区域中产生的共振信号的RF线圈系统（47,49），所述区域相邻地位于第一方向（57）上，每个第一 以及包括至少一个表面线圈的第二RF线圈系统。 该装置特别用于检查布置在支撑面（43）上的患者的脊柱，第一区域包含脊柱（T型脊柱）的胸段，第二区域包含腰椎段（L型脊柱 ）。 为了使得能够容易地将第二RF线圈系统（49）的位置适应到单个患者的L脊的位置，第一RF线圈系统（47）被布置成相对于支撑面静止（ 在第一线圈平面（53）中基本上平行于支撑面延伸，而第二RF线圈系统（49）布置成在第二线圈平面（61）中沿第一方向（57）可移位，第二线圈平面 平行于第一线圈平面（53）延伸。
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公开(公告)号：US4457177A
公开(公告)日：1984-07-03
申请号：US460321
申请日：1983-01-24
CPC分类号： G10K11/34
摘要： The transmitter comprises an array of electro-acoustic transducers (1), each of which is connected to an oscillator circuit (9) which has a start input (11). The start inputs (11) successively receive start signals from a start signal generator (13) which comprises a number of comparators (15), each of which comprises a first input (17) and a second input (19). The first inputs (17) are together connected to an output of a sawtooth generator (21), the second input (19) of each comparator (15) are connected to a direct voltage source (23). A direct voltage source (23) is provided for each start signal to be successively generated at least some of the direct voltage sources being controllable in common.
摘要翻译： 发射器包括一组电声换能器（1），每个电声换能器（1）连接到具有起动输入端（11）的振荡器电路（9）。 起始输入（11）从包括多个比较器（15）的起始信号发生器（13）连续接收起始信号，每个比较器包括第一输入端（17）和第二输入端（19）。 第一输入端（17）一起连接到锯齿波发生器（21）的输出端，每个比较器（15）的第二输入端（19）连接到直流电压源（23）。 为每个起始信号提供直流电压源（23）以连续产生，至少一些直流电压源是可共同控制的。
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公开(公告)号：US5483159A
公开(公告)日：1996-01-09
申请号：US240192
申请日：1994-05-09
CPC分类号： G01R33/3678 , G01R33/34007 , G01R33/34046 , G01R33/34053 , G01R33/34061 , G01R33/3628
摘要： A quadrature coil system which includes the following elements. (1) First and second electric main conductors which are situated at a distance from one another in a first plane and a second plane, respectively, and each of which is formed as a loop with an opening, the main conductors having mainly the same orientation. (2) First and second connection conductors, each of which constitutes an electric connection between the free ends of the first and second main conductors, which free ends are situated to corresponding sides of the opening. (3) An electric connection device which is connected to the conductors so that first and second sets of turns are formed which are suitable to generate and/or receive first and second magnetic fields, respectively, which are mutually orthogonally directed. (a) There is provided at least one third connection conductor which constitutes an electric connection between a point on the first main conductor, being situated between the two free ends, and a corresponding point on the second main conductor; (b) each of the first and second connection conductors consist of substantially equal first and second connection conductor portions, the first connection conductor portions being connected to the free ends of the first main conductor and the second connection conductor portions being connected to the free ends of the second main conductor; (c) the four ends of the first and second connection portions are electrically connected, via an electric connection network, to one another and to the electric connection device.
摘要翻译： 正交线圈系统，包括以下元件。 （1）分别在第一平面和第二平面中彼此相隔一定距离的第一和第二电主导体，并且每个主导体形成为具有开口的环，主导体具有主要相同的取向 。 （2）第一和第二连接导体，每个连接导体构成第一和第二主导体的自由端之间的电连接，该自由端位于开口的相应侧面。 （3）一种电连接装置，其连接到导体，使得形成第一和第二组匝，其适合于分别相互正交地产生和/或接收第一和第二磁场。 （a）提供至少一个第三连接导体，其构成位于第一主导体之间的位于两个自由端之间的点与第二主导体上的对应点之间的电连接; （b）第一和第二连接导体中的每一个由基本相同的第一和第二连接导体部分组成，第一连接导体部分连接到第一主导体的自由端，第二连接导体部分连接到自由端 的第二主导体; （c）第一和第二连接部分的四个端部经由电连接网络彼此电连接到电连接装置。
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公开(公告)号：US5347220A
公开(公告)日：1994-09-13
申请号：US990328
申请日：1992-12-09
CPC分类号： G01R33/34046
摘要： A magnetic resource apparatus includes a mainly cylindrical RF coil (9) having a longitudinal directed central axis (33) and symmetry plane (35) which contains the central axis and a reference plane (37). The reference plane extends perpendicularly to the symmetry plane and also contains the central axis. The coil (9) has a number of rod conductors (39) which extend, parallel to the central axis (33), across a mainly cylindrical surface, and loop conductors (41) which extend around the central axis near the ends of the rod conductors, the length of the rod conductors (39) situated near the symmetry plane (35) being greater than that of the rod conductors situated near the reference plane (37). In order to enable sharp and low-noise images to be made of the neck of a patient, the rod conductors (39) which are situated near the symmetry plane (35) and to one side of the reference plane (37) have a length which is greater than that of the rod conductors situated near the symmetry plane and to the other side of the reference plane.
摘要翻译： 一种磁性资源装置包括具有纵向定向中心轴线（33）和包含中心轴线的对称平面（35）和参考平面（37）的主要为圆柱形的RF线圈（9）。 参考平面垂直于对称平面延伸并且还包含中心轴。 线圈（9）具有多个平行于中心轴线（33）延伸穿过主要圆柱形表面的杆状导体（39），环形导体（41）围绕杆的端部附近的中心轴线延伸 位于靠近对称平面（35）的棒状导体（39）的长度大于位于参考平面（37）附近的杆状导体的长度。 为了能够使患者的颈部形成锐利和低噪音的图像，位于对称平面（35）附近和参考平面（37）的一侧的杆状导体（39）的长度 其大于位于对称平面附近和参考平面的另一侧的棒状导体的尺寸。
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9.发明授权
公开(公告)号：US4777440A
公开(公告)日：1988-10-11
申请号：US59284
申请日：1987-06-08
CPC分类号： G01R33/3628
摘要： In a magnetic resonance imaging apparatus an RF rotating field is generated by applying RF energy to two mutually perpendicular coil systems, a 1/4.lambda. lead being provided between the connection points of the systems. In that case the drive points and the detection signal output points are not the same, so that in the case of a change-over from transmission to reception, the connection between the transmitter and the receiver must be switched over. In the magnetic resonance imaging apparatus in accordance with the invention, a phase difference of 180.degree. is created between two junctions by means of 1/4.lambda. leads so that an intermediate junction will actually not carry a voltage. This point (for transmission and reception, two different points) is connected to ground by means of a PIN diode. A simplification enables connection of the transmitter as well as the receiver to the transmitter/receiver coil system via a single coaxial cable.
摘要翻译： 在磁共振成像设备中，通过将RF能量施加到两个相互垂直的线圈系统来产生RF旋转场，在系统的连接点之间提供1/4λ引线。 在这种情况下，驱动点和检测信号输出点不相同，因此在从传输到接收的转换的情况下，必须切换发射机和接收机之间的连接。 在根据本发明的磁共振成像装置中，通过1/4λ引线在两个结之间产生180°的相位差，使得中间结实际上不承载电压。 此点（用于发送和接收两个不同点）通过PIN二极管连接到地。 简化使发射机和接收机通过单根同轴电缆连接到发射机/接收机线圈系统。
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10.发明授权
公开(公告)号：US4707662A
公开(公告)日：1987-11-17
申请号：US752281
申请日：1985-07-05
CPC分类号： G01R33/34069 , G01R33/34061 , G01R33/3628
摘要： For increasing the sensitivity of an MR apparatus when measuring comparatively high frequencies, the radio frequency excitation measurement coil (10, 30) is divided into two individual symmetrically drivable and readable coil halves (32, 34), respectively. The mutual connection of central connections of the coil halves can be realized by means of a balun (54) but for this purpose any other symmetrical form of coupling, for example using a strip-line transformer (70) or suitably dimensioned coaxial cables (60, 62) may alternatively be used.
摘要翻译： 为了在测量较高频率时增加MR装置的灵敏度，射频激励测量线圈（10,30）分别被分成两个单独的对称驱动和可读的半导体（32,34）。 线圈半部的中心连接的相互连接可以通过平衡 - 不平衡变压器（54）实现，但为此目的，可以使用任何其它对称形式的耦合，例如使用带状线变压器（70）或适当尺寸的同轴电缆（60） ，62）。
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