Nuclear magnetic resonance

Abstract

A passive filter circuit for simultaneous dual nuclear magnetic resonance quadrature transmission and reception is configured to apply to an input a quadrature phase shift of a first polarity at the Larmor frequency of a first nucleus and a quadrature phase difference of a second polarity opposite the first polarity at the Larmor frequency of a second nucleus.

Description

Detailed Description of the Invention

[0001] [Technical field] TECHNICAL FIELD Embodiments of the present disclosure relate to nuclear magnetic resonance (NMR). [Background technology] The NMR instrument is fitted with a longitudinal static magnetic field (B 0 ) and the transverse oscillating magnetic field (B 1 ) is given. B 1 The magnetic field is B 0 It is generated by using a radio frequency (RF) coil that is perpendicular to the magnetic field and resonates at the Larmor frequency. The Larmor frequency is determined by the gyromagnetic ratio of the nuclei of interest and the static magnetic field (B 0 The polarity (sign) of the gyromagnetic ratio of the nucleus in question is determined by the strength of the B 1 Required angular direction of rotation of the magnetic field (B 1 Determine the left and right of the coordinate system for the circular polarization of the magnetic field. The left and right of the coordinate system required for the circular polarization changes with the polarity of the gyromagnetic ratio.

[0002] External static magnetic field (B 0 ), the angular momentum of the nuclear spins aligns in opposite directions in nuclei with positive and negative gyromagnetic ratios. Therefore, when dual-frequency NMR is applied to nuclei with positive and negative gyromagnetic ratios, the required oscillating magnetic field (B 1 ) are opposite to each other. When performing orthogonal excitation / detection, clockwise circular polarization is required for nuclei with positive gyromagnetic ratio, and counterclockwise circular polarization is required for nuclei with negative gyromagnetic ratio. [Summary of the Invention] In accordance with various, but not necessarily all, embodiments, examples are provided as set forth in the appended claims.

[0003] According to various, but not necessarily all, embodiments, a passive filter circuit for simultaneous dual nuclear magnetic resonance quadrature transmission and reception is provided, the circuit being configured to apply to an input a quadrature phase shift (phase difference) of a first polarity at the Larmor frequency of a first nucleus and a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of a second nucleus. [Brief description of the drawings]

[0004] Some embodiments will now be described with reference to the accompanying drawings. [Figure 1A] FIG. 1A shows an in-phase signal. [Figure 1B] FIG. 1B shows a quadrature signal having a quadrature phase offset of +90° (−270°) from the in-phase signal, and a quadrature signal having a quadrature phase offset of −90° from the in-phase signal. [Diagram 2] FIG. 2 shows a passive filter circuit comprising multiple cascaded filter modules. [Diagram 3] FIG. 3 illustrates an example of a filter module. [Figure 4A] FIG. 4A illustrates a passive filter circuit for 1H and 129Xe that includes three cascaded filter modules. [Figure 4B] FIG. 4B illustrates an example of the filter module of FIG. 4A. [Figure 5A] FIG. 5A illustrates the phase change caused by the filter module. [Figure 5B] FIG. 5B illustrates the phase change caused by a passive cascode filter circuit. [Figure 6] FIG. 6 illustrates an example of a filter module. [Figure 7A] FIG. 7A illustrates the magnitude of the S-parameters S11 and S21 of the filter module. [Figure 7B] FIG. 7B illustrates the phase of the S-parameters S11 and S21 of the filter module. [Figure 8] FIG. 8 illustrates another example of a filter module. [Figure 9] FIG. 9 illustrates an example of an apparatus for performing simultaneous dual nuclear magnetic resonance orthogonal transmission and reception. [Figure 10A] FIG. 10A illustrates an embodiment of the device using a standard wideband hybrid circuit. [Figure 10B] FIG. 10B illustrates an exemplary embodiment of an apparatus in which a network of passive filter circuits is configured to provide a dual-mode quadrature hybrid circuit. [Figure 11] FIG. 11 illustrates an example of a Nuclear Magnetic Resonance (NMR) system. [Figure 12] FIG. 12 illustrates an example of a Nuclear Magnetic Resonance (NMR) system. [Figure 13] FIG. 13 illustrates an example of a Nuclear Magnetic Resonance (NMR) system. [Figure 14] FIG. 14 illustrates an example of a Nuclear Magnetic Resonance (NMR) system. [Figure 15] FIG. 15 illustrates an example of a xenon hyperpolarizer using a Nuclear Magnetic Resonance (NMR) system. [Figure 16A] FIG. 16A illustrates the phase change for multiple changes in the Larmor frequencies of the first and second nuclei to obtain a desired relative phase offset. [Figure 16B] FIG. 16B illustrates the phase change for multiple changes in the Larmor frequencies of the first and second nuclei to obtain a desired relative phase offset. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0005] [Detailed Description of the Invention] In the following examples, simultaneous dual nuclear magnetic resonance for two nuclei with gyromagnetic ratios of opposite polarity is achieved by simultaneously tuning the transverse components of the precessing spin magnetization vectors of the nuclei. The spin magnetization vectors precess at different Larmor frequencies and in different directions (polarities) for the two nuclei. The transverse components of the precessing spin magnetization vectors are rotating phasors in the transverse plane. The phasors rotate at different Larmor frequencies and in different directions for the two nuclei.

[0006] To achieve the desired tuning, the NMR system transmits and receives a first transverse magnetic field for the first nucleus and a second transverse magnetic field for the second nucleus, the first transverse magnetic field being a rotating phasor in the transverse plane with a Larmor frequency and a rotation direction that matches the transverse component of the precessing spin magnetization vector of the first nucleus, and the second transverse magnetic field being a rotating phasor in the transverse plane with a Larmor frequency and a rotation direction that matches the transverse component of the precessing spin magnetization vector of the second nucleus and that is opposite to the rotation direction of the first transverse magnetic field.

[0007] Quadrature motion is associated with a rotating phasor in the cross-plane. A rotating phasor can be represented by an in-phase signal in one direction and a quadrature signal in the other direction that are orthogonal to each other. If the quadrature signal has a quadrature phase offset of +90° from the in-phase signal, the phasor rotates in one direction, and if the quadrature signal has a quadrature phase offset of -90° from the in-phase signal, the phasor rotates in the opposite direction.

[0008] Figure 1A illustrates an in-phase signal. Figure 2A illustrates a quadrature signal that is offset in quadrature from the in-phase signal by +90° (−270°) and a quadrature signal that is offset in quadrature from the in-phase signal by −90°.

[0009] The objective is to achieve a quadrature phase shift of a first polarity at the Larmor frequency of a first nucleus, and a quadrature phase difference of a second polarity, opposite to the first polarity, at the Larmor frequency of a second nucleus.

[0010] This can be accomplished upon transmission and / or reception.

[0011] The following description relates to a passive filter circuit 10 for simultaneous dual nuclear magnetic resonance quadrature transmission and reception configured to apply to its inputs a quadrature phase shift of a first polarity at the Larmor frequency of a first nucleus and a quadrature phase difference of a second polarity opposite the first polarity at the Larmor frequency of a second nucleus.

[0012] The input can be either the input for the next transmission or the received input.

[0013] The passive filter circuit 10 can be constructed, for example, as a second order filter or a higher order filter, for example a second order filter with two zeros, or a third order filter with three zeros.

[0014] A second order filter may, for example, have a first resonance at the Larmor frequency of a first nucleus and a second resonance at the Larmor frequency of a second nucleus. The first and second resonances are separate and distinct from one another, i.e., are not included in one broadband resonance. In some, but not necessarily all, examples, there may be similar, low insertion losses at the Larmor frequency of the first nucleus and the Larmor frequency of the second nucleus.

[0015] 2, the passive filter circuit 10 may include multiple cascaded filter modules 20. The multiple filter modules 20 are connected in series.

[0016] In some instances, but not necessarily all, the cascade filter modules 20 are all identical.

[0017] Each cascade filter module 20 is configured to provide a relative phase change that, when summed across the passive filter circuit 10, results in an output 14 that, compared to the input signal 11, has a quadrature phase change of a first polarity at the Larmor frequency of a first nucleus and a quadrature phase change of a second polarity opposite the first polarity at the Larmor frequency of a second nucleus.

[0018] An input signal 11 at an input 12 corresponds to FIG. 1A, and an output signal 13 at an output 14 corresponds to FIG. 1B.

[0019] 3 illustrates an example of a filter module 20. The filter module 20 includes an optional impedance matching block 22, a phase rotation block 24, and a phase offset block 26.

[0020] The phase rotation block 24 applies a first phase shift Δφ for a certain time delay etc. 1 in a first direction at the Larmor frequency of the first nucleus, the first phase shift being proportional to the Larmor frequency of the first nucleus.

[0021] Phase rotation block 24 introduces a second phase shift Δφ for the same time delays as above, etc. 2 in a second direction and at the Larmor frequency of the second nucleus. 2 is proportional to the Larmor frequency of the second nucleus and has the same polarity as the first phase shift.

[0022] Therefore, Δφ 1 / Δφ 2 =|γ 1 / γ 2 | where γ 1 is the gyromagnetic ratio of the first nucleus, and γ 2 is the gyromagnetic ratio of the second nucleus. Therefore, Δφ 2 = Δφ 1 / |R|, where |R|=|γ 1 / γ 2 | is the gyromagnetic ratio of the first nucleus, γ 1 and the gyromagnetic ratio of the second nucleus γ 2 is the absolute value of the ratio of

[0023] In the illustrated example, a first phase shift +X is applied at the Larmor frequency of a first nucleus, and a second phase shift +X / |R| is applied at the Larmor frequency of a second nucleus.

[0024] Phase offset block 26 determines a first phase shift Δφ at the Larmor frequency of the first nucleus. 1 and the second phase shift Δφ at the Larmor frequency of the second nucleus 2 and generating a phase difference β between the first and second phase shifts after the offset by applying a relative phase offset θ between the first and second phase shifts. 2 * If b, then β = Δφ 1 -Δφ 2 * b = Δφ 1 (1-b / |R|).

[0025] The phase difference β is summed across the N cascade filter modules to provide an output 14 having a quadrature phase change of a first polarity at the Larmor frequency of the first nucleus and a quadrature phase change of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus.

[0026] Therefore, the sum of the N relative phase differences β is a relative phase difference of 180°.

[0027] First phase shift Δφ at the Larmor frequency of the first nucleus 1 and the second phase shift Δφ at the Larmor frequency of the second nucleus 2 The offset θ between produces a phase difference β between the first and second phase shifts after the offset, which can be multiplied by the total number to obtain a final + / - 90° phase difference at the Larmor frequency of the first nucleus and a final - / +90° phase difference at the Larmor frequency of the second nucleus. The quadrature phase difference at the Larmor frequency of the second nucleus is opposite in sense to the quadrature phase difference at the Larmor frequency of the second nucleus.

[0028] The passive filter circuit 10 includes a filter module 20 that provides a first phase shift Δφ at the Larmor frequency of a first nucleus. 1 and the second phase shift Δφ at the Larmor frequency of the second nucleus 2and the number of cascade filter modules 20 can be designed to produce a quadrature phase shift of a first polarity at the Larmor frequency of the first nucleus and a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus.

[0029] When it is desired to have simultaneous dual nuclear magnetic resonance for various combinations of first and second nuclei with opposite polarity of the gyromagnetic ratio, the passive filter circuit 10 is adapted to filter a first phase shift Δφ at the Larmor frequency of the first nucleus. 1 and the second phase shift Δφ at the Larmor frequency of the second nucleus 2 In some examples, the passive filter circuit 10 can be designed to vary the number of cascade filter modules 20, i.e., cascade filter modules 20 can be added or removed from the filter circuit 10.

[0030] Next, a specific first nucleus 1 H, the second nucleus 129 A specific example will be given with Xe, although it will be appreciated that other combinations of first and second nuclei can also be simultaneously probed using passive filter circuit 10.

[0031] 1 H has a gyromagnetic ratio of 42.57, 129 Xe has a gyromagnetic ratio of -11.77.

[0032] These gyromagnetic ratios are opposite in polarity to each other. Therefore, the static magnetic field B 0 In , the spin magnetization vectors are aligned in opposite directions and precess in opposite senses.

[0033] The ratio of the Larmor frequencies |R| (which is also the ratio of the gyromagnetic ratios) is 3.6.

[0034] As shown in Figure 4A, 1 H and 129The passive filter circuit 10 for Xe may include three cascade filter modules 20, where all the cascade filter modules 20 are identical.

[0035] Each cascade filter module 20, as shown in FIG. 5A, 1 At the Larmor frequency of H, the phase shift is -90°, 129 The three cascade filter modules 20 are combined to provide a phase shift of -30° at the Larmor frequency of Xe, as shown in FIG. 1 At the Larmor frequency of H, the phase shift is -270° (equivalent to a phase shift of +90°), 129 At the Larmor frequency of Xe, a phase shift of +90° is given. Thus, the three cascade filter modules 20 are combined to produce 1 At the Larmor frequency of H, the quadrature phase shift of the first polarity is 129 At the Larmor frequency of Xe, a quadrature phase change of a second polarity opposite to the first polarity is given.

[0036] Figure 4B 1 H and 129 1 illustrates an example of a filter module 20 for Xe. The filter module 20 includes an optional impedance matching block 22, a phase rotation block 24, and a phase offset block 26.

[0037] Phase rotation block 24 applies a first phase shift of −90° in a first direction, 1 The first phase shift is 1 It is proportional to the Larmor frequency of H.

[0038] Phase rotation block 24 applies a second phase shift of −25° in the first direction, 129 A second phase shift of -25° is provided at the Larmor frequency of Xe. 129 It is proportional to the Larmor frequency of Xe and has the same polarity as the first phase shift.

[0039] The phase shift ratio -90° / -25° is the ratio |R|=|γ 1 / γ 2 |=3.6, where γ 1 teeth 1 is the gyromagnetic ratio of H, and γ 2 teeth 129 is the gyromagnetic ratio of Xe. 1 At the Larmor frequency of H, a first phase shift of −90° is applied, 129 At the Larmor frequency of Xe a second phase shift of -90° / 3.6=-25° is applied.

[0040] The phase offset block 26 is 1 A first phase shift of −90° at the Larmor frequency of H and 129 and a circuit arrangement configured to generate a phase difference β between the first and second phase shifts after the offset by applying a relative phase offset θ between the first and second phase shifts of −25° at the Larmor frequency of Xe. As shown in FIG. 5A, the second phase difference after the offset is −30° and the phase difference β is 60°.

[0041] By summing the phase difference (60°) across the three cascaded filter modules, as shown in FIG. 5B, 1 A quadrature phase shift of the first polarity (+90) at the Larmor frequency of H; 129 It provides an output 14 having a quadrature phase shift (-90) of a second polarity opposite the first polarity at the Larmor frequency of Xe.

[0042] In this example, the circuit configuration of the phase rotation block 24 is as follows: 1 At the Larmor frequency of the H nucleus, the phase shift is -90°, 129 At the Larmor frequency of Xe nuclei, a phase shift of approximately −25° is applied, and the circuitry of offset block 26 is 129 At the Larmor frequency of the Xe nucleus 1 The laser is configured to apply a phase shift offset of approximately −5° compared to the Larmor frequency of H nuclei.

[0043] 6 illustrates an example of a filter module 20. The filter module 20 is a second order filter with two zeros.

[0044] FIG. 7A illustrates the magnitude of the S-parameters S11 and S21 of the filter module 20 shown in FIG. 6. FIG. 7B illustrates the argument (phase) of the S-parameter S12 of the filter module 20 shown in FIG. 6. In both figures, the label m1 is 129 At the Larmor frequency of Xe, 17.65 MHz, the label m2 1 This is at 63.86 MHz, which is the Larmor frequency of H.

[0045] The filter module 20 is a second order filter module, having a first resonance at the Larmor frequency of a first nucleus and a second resonance at the Larmor frequency of a second nucleus. The first and second resonances are separate and distinct from one another, i.e., they are not included in a single broadband resonance. In the illustrated example, graph S11 of FIG. 7A has two narrow passbands, one 1 One at the Larmor frequency of H (m2) 129 This is at the Larmor frequency of Xe (m1).

[0046] At the Larmor frequency of the first nucleus and the Larmor frequency of the second nucleus, the insertion losses that can be present are similar and low.

[0047] FIG. 7B illustrates the phase of the S-parameter S12 of the filter module 20 shown in FIG. 6. In the illustrated example, the graph S11 is 1 The phase difference at the Larmor frequency (m2) of H is almost -90°. 129 It has a phase difference of approximately -30° at the Larmor frequency of Xe (m1).

[0048] The filter module 20 has two parallel paths from each port to ground through capacitors C1 and C2. An LC network is connected between these ports. The LC network includes one or more inductors (L1, L2) connected in series in a parallel LC circuit. The parallel LC circuit includes an inductor L3 and a capacitor C3 connected in parallel. The LC network separating the two ground paths provides separation of two resonances (two zeros). The tuning of the resonances and phase difference is obtained by selecting the appropriate values ​​of the components C1, C2, C3, L1, L2, and L3.

[0049] In the illustrated examples, but not necessarily in all examples, the LC network is symmetrically comprised of series connected inductor L1, a parallel LC circuit, and inductor L2. However, in other examples, inductors L1 and L2 can be combined as one inductor, in which case only one of the inductors is used with a combined value. A symmetrical arrangement of the inductors is not required.

[0050] In the illustrated example, but not necessarily in all examples, capacitors C1 and C2 are symmetrical and have the same value.

[0051] In the illustrated example, the reflected S-parameter (S11) and transferred S-parameter (S12) characteristics shown in Figures 7A and 7B are obtained by using values ​​of 89 nH for L1 and L2, 49 pF for C1 and C2, 46 nH for L3, and 252 pF for C3. This results in a specific static magnetic field B 0 In this case, it is 63.86MHz. 1 Resonance occurs at the Larmor frequency of H (m2), which is 17.65 MHz. 129 Resonance occurs at the Larmor frequency of Xe (m1).

[0052] The circuit is simple because the phase of the first nucleus, Δφ 1 ( 1 H Larmor frequency is -90°) and the phase of the second nucleus Δφ 2 (129 This is because, for the Larmor frequency of Xe (-30°), the capacitor values ​​required for C1 and C2 are the same, so no additional elements are required for impedance matching. The reason for this is the following relationship:

[0053]

number

[0054] Here, N is the number of cascade blocks.

[0055] In some examples, for example, the values ​​of elements C1, C2, C3, L1, L2, and L3 may be variable, thereby allowing the filter module 20 to be subjected to different values ​​of the static magnetic field B 0 The same circuit arrangement can be utilized and means are provided for proportionally varying the component values.

[0056] In some examples, for example, the values ​​of elements C1, C2, C3, L1, L2, and L3 may be variable, thereby allowing the filter module 20 to be adapted to operate on various combinations of first and second nuclei.

[0057] The combination of inductor L1 and capacitor C2 and the combination of inductor L2 and capacitor C1 provide a phase rotation block 24, and the combination of inductor L3 and capacitor C3 provide a phase offset block 26.

[0058] 6 is a low-pass π network. Filter module 20 can also be constructed using other circuits such as a high-pass π network, a low-pass T network, a high-pass T network, etc., as shown in FIG.

[0059] 9 illustrates an example of an apparatus 100 for simultaneous dual nuclear magnetic resonance quadrature transmission and reception. As explained above, the apparatus 100 includes one or more passive filter circuits 10.

[0060] The apparatus 100 outputs a first output 112 having a quadrature phase difference of a first polarity at the Larmor frequency of a first nucleus. 1 ,112 2 while providing a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus.

[0061] In the example shown, the first nucleus is 1 H, the second nucleus is 129 Xe. First output 112 1 ,112 2 produces a first output signal 13 having a quadrature phase difference of a first polarity at the Larmor frequency of the first nucleus compared to an in-phase signal 1 and a second output signal 13 having a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus. 2 However, the device 100 can operate with various combinations of atomic nuclei with opposite polarity in the gyromagnetic ratio.

[0062] The device 100 has a first output 112 1 ,112 2 where the first output 112 1 ,112 2 In between, 1 At the Larmor frequency of H, it is +90° (-270°), 129 At the Larmor frequency of Xe there is a quadrature phase difference which is -90° (opposite polarity).

[0063] The device 100 has an output 112 1 ,112 2 In this case, it acts as a quadrature hybrid coupler, splitting the RF power into in-phase (0°) RF power and four-phase (+ / -90°) RF power.

[0064] The device 100 has an output 112 1 ,112 22 to couple to an orthogonally or circularly polarized RF coil arrangement 204 via a .

[0065] FIG. 10A illustrates an embodiment of the apparatus 10 used in conjunction with a standard / representative wideband or multi-band hybrid coupler.

[0066] In this example, the input to the wideband or multiband hybrid coupler 102 is converted to an in-phase output at port 3 and a quadrature output at port 2. This is a standard wideband or multiband hybrid coupler, and is coupled to the Larmor frequency of the first nucleus (e.g. 1 H) and the Larmor frequency of the second nucleus (e.g. 129 Xe) generate the same quadrature phase difference.

[0067] The in-phase output from port 3 is passed through a conventional wideband phase shifter 104 to a second output 112. 2 The Larmor frequency of the first nucleus (e.g. 1 H) and the Larmor frequency of the second nucleus (e.g. 129 Xe), the same quadrature phase difference is added.

[0068] The quadrature output from port 2 is passed through a passive filter circuit 10 to a first output 112. 1 The Larmor frequency of the first nucleus (e.g. 1 H) and the Larmor frequency of the second nucleus (e.g. 129 For the first nucleus (Xe), different quadrature phase differences are applied: a quadrature phase shift of a first polarity at the Larmor frequency of the first nucleus, and a quadrature phase shift of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus.

[0069] The output ports 112 of the passive filter circuit 10 and the conventional wideband phase shifter 104 1 and 112 2 represents a differential first output signal 13 having a quadrature phase shift of a first polarity at the Larmor frequency of the first nucleus. 1and a differential second output signal 13 having a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus. 2 and generate.

[0070] 10B illustrates an embodiment of the apparatus 100. The network of passive filter circuits 10 is configured to provide a dual-mode quadrature hybrid circuit 110.

[0071] In this example, the input to the dual mode quadrature hybrid circuit 110 at port 1 produces an in-phase output (second output 112) at port 3. 2 ) and a quadrature output (first output 112 1 The output between ports 2 and 3 of the dual-mode quadrature hybrid circuit 110 is a first output signal 13 having a quadrature phase shift of a first polarity at the Larmor frequency of the first nucleus. 1 and a second output signal 13 having a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus. 2 and supply.

[0072] The dual mode quadrature hybrid circuit 110 has a first output 112 as described above. 1 and the second output is 112 2 The present invention includes a plurality of passive filter circuits 10, such as at least one passive filter circuit 10 connected between a

[0073] 10B shows an example of a dual-mode quadrature hybrid circuit 110 having a passive filter circuit 10 connected between port 1 and port 2, a passive filter circuit 10 connected between port 2 and port 3, a passive filter circuit 10 connected between port 3 and port 4, and a passive filter circuit 10 connected between port 4 and port 1. However, the characteristic impedances of these passive filters 10 vary depending on the design of a typical hybrid coupler.

[0074] Each passive filter circuit 10 is configured to filter the Larmor frequency of a first nucleus (e.g. 1H) and the Larmor frequency of the second nucleus (e.g. 129 Xe), different quadrature phase shifts are applied, the different quadrature phase shifts being a quadrature phase shift of a first polarity at the Larmor frequency of the first nucleus and a quadrature phase shift of a second polarity, opposite to the first polarity, at the Larmor frequency of the second nucleus.

[0075] FIGURE 11 illustrates an example of a nuclear magnetic resonance (NMR) system 200. A magnet 202 provides a longitudinal magnetic field B in a direction z. A radio frequency coil 204 provides a transverse magnetic field B in the xy plane orthogonal to z. 1 Gives.

[0076] The simultaneous dual nuclear magnetic resonance quadrature transmission and reception device 100 is used to transmit radio frequency power via a radio frequency coil 204 and also to receive radio frequency power via the radio frequency coil 204. FIG. 12 illustrates an example of the device 100 coupled to a radio frequency coil arrangement 204. In this example, but not necessarily in all examples, the device 100 connects to the radio frequency coil 204 via one or more baluns. The baluns 130 couple the input signal 13 from the device 100 to the accelerometer 120. 1 ,13 2 , which produces a differential output signal equivalent to:

[0077] The apparatus 100 outputs a first output signal 13 having a quadrature phase difference of a first polarity at the Larmor frequency of a first nucleus. 1 and a second output signal 13 having a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus. 2 The device is configured to provide:

[0078] Transmitting, 1st output signal 13 1 generates a first circularly polarized magnetic field via the RF coil 204 that couples with the spin magnetization vector of the first nuclei to generate a second output signal 13 2 generates a second circularly polarized magnetic field that couples with the spin magnetization vector of the second nuclei via the same or a different RF coil 204. The circular polarizations of the first and second magnetic fields are opposite in the coordinate system (angular direction), i.e., one is left-handed circularly polarized and the other is right-handed circularly polarized.

[0079] Receiving, first output signal 13 1 detects a first circularly polarized magnetic field coupled to the spin magnetization vector of the first nucleus via the RF coil 204 and generates a second output signal 13 2 detects a second circularly polarized magnetic field coupled to the spin magnetization vector of the second nuclei via the same or a different RF coil 204. The circular polarizations of the first and second magnetic fields are opposite in the left and right coordinate system (angular direction), i.e., one is left-handed circularly polarized and the other is right-handed circularly polarized.

[0080] The system 200 is configured as a transmitter for simultaneous dual nuclear magnetic resonance and / or as a receiver for simultaneous dual nuclear magnetic resonance quadrature transmission and reception.

[0081] In this example, but not necessarily in all examples, the same radio frequency coil 204 is used to generate both the first and second magnetic fields. In other examples, different radio frequency coils 204 can be used to generate both the first and second magnetic fields.

[0082] The system 200 has an output 112 having a quadrature phase difference of a first polarity at the Larmor frequency of a first nucleus responsible for generating a first magnetic field and a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of a second nucleus responsible for generating a second magnetic field. 1 ,112 2 2. The antenna includes a first coil arrangement 204 coupled to a first magnetic field 206, wherein one of the first and second magnetic fields is right-handed circularly polarized and the other of the first and second magnetic fields is left-handed circularly polarized.

[0083] The system 200 performs simultaneous dual nuclear magnetic resonance on a first nucleus and a second nucleus, where the first nucleus and the second nucleus have gyromagnetic ratios of opposite polarity. The system 200 may include a passive filter circuit 10 and / or an apparatus 100. The system 200 is configured to perform simultaneous dual nuclear magnetic resonance on the first nucleus and the second nucleus without time-division switching.

[0084] Figure 13 is a system 200 similar to that shown in Figure 12. In Figure 12, the RF coil configuration 204 is a circularly polarized configuration, where a single birdcage coil is used for both the first and second nuclei. However, in Figure 13, the RF coil configuration 204 is a quadrature coil configuration, where separate RF coils are used to generate the quadrature components of the transverse magnetic field. Thus, the output from the coupler 206 is coupled to the different coils 204. i Bind to.

[0085] Coupler 206 may be a wideband or multiband 180 degree power divider (sometimes known as a rat race coupler or Wilkinson splitter).

[0086] Coil Pair 204 1 ,204 3 are disposed on opposite sides of the application. 2 ,204 4 are disposed on opposite sides of the application. 1 -204 2 ,204 2 -204 3 ,204 3 -204 4 , and 204 4 -204 1 generates an orthogonal component of the transverse magnetic field.

[0087] Coil 204 1 ,204 2 ,204 3 ,204 4 is the first nucleus (e.g. 1 H) to generate a first magnetic field having a first circular polarization. 1 ,204 2 ,204 3 ,204 4 The phase difference between the first nucleus and the second nucleus is the Larmor frequency (e.g. 1 H) changes by -90°.

[0088] Coil 204 1 ,2042 ,204 3 ,204 4 is the second nucleus (e.g. 129 Coil 204 generates an orthogonal transverse magnetic field component at the Larmor frequency of Xe to generate a second magnetic field having a second circular polarization. 1 ,204 2 ,204 3 ,204 4 The phase difference between the two is the Larmor frequency of the second nucleus (e.g. 129 Xe), the angle changes by +90°. The first and second polarizations are on opposite sides of the coordinate system (angle direction) when applied.

[0089] Output signal 13 1 ,13 2 will output 112 1 ,112 2 The first output signal 13 can be defined using 1 is the Larmor frequency of the first nucleus (e.g. 1 H) gives a phase difference of +90°. 2 is the Larmor frequency of the first nucleus (e.g. 1 H) gives a phase difference of -90°.

[0090] Output 112 1 The signal from is split by a power divider / rat race coupler 206 and fed to coil 204. 1 The common signal and coil 204 3 This results in an anti-phase signal leading to

[0091] Output 112 2 The signal from is split by a power divider / rat race coupler 206 and fed to coil 204. 2 The common signal and coil 204 4 This results in an anti-phase signal leading to

[0092] The system 200 shown in FIG. 13 can be constructed as a wearable system dual-tuned quadrature transmit / receive array coil that is worn on the subject and ergonomically fits the subject as a jacket design. 1 H signal and129 When used in conjunction with the claimed design feature of a dual-tuned hybrid that uses counter-rotating quadrature phase to both transmit and receive Xe signals, the same wearable coil can be interfaced to an MRI system with a single passive circuit design that requires no mechanical or electrical switching.

[0093] In some examples, the jacket 500 at least partially covers the application. For example, the jacket 500 can be worn around the upper torso of a human. In some examples, the jacket 500 can be designed to be worn over the shoulders. Thus, the coil configuration 204 can be configured as a jacket 500 that is worn by an application, such as a human application. In some examples, the jacket 500 fits over the application by some attachment member.

[0094] The jacket 500 can also be a passive structure. In some examples, the jacket 500 includes the coil 204 and all or a portion of the device 100. In this example, the jacket 500 can include one or more passive filter circuits 10. For example, in some, but not necessarily all, examples, the jacket 500 can include a dual mode quadrature hybrid circuit 110. In other examples, the passive structure jacket 500 includes the coil 204 but not the device 100, and the device 100 is connected to the jacket 500.

[0095] The jacket can, for example, probe a first nucleus and / or a second nucleus, for example, the jacket can be used with one or more passive filters 10 to simultaneously probe a combination of first and second nuclei having opposite polarities in the gyromagnetic ratio.

[0096] However, it should be noted that jacket 500 can also be used, for example, in conjunction with other circuitry, such as active switching circuitry, to simultaneously probe combinations of first and second nuclei having opposite polarity gyromagnetic ratios.

[0097] Thus, the passive structure jacket 500 for dual orthogonal nuclear magnetic resonance transmission and reception with respect to an application object includes a circuit configuration configured to generate and detect a first magnetic field having a first circular polarization at the Larmor frequency of a first nucleus, and to generate and detect a second magnetic field having a second circular polarization at the Larmor frequency of the first nucleus, where the first circular polarization is opposite to the second polarization at the application object.

[0098] In at least some examples, the passive structure jacket 500 comprises at least a first coil pair 204 generating a first component of a transverse magnetic field and at least a second coil pair 204 generating a second component of the transverse magnetic field, and means for calibrating the alignment of the first coil pair and / or the alignment of the second coil pair.

[0099] In at least some examples, the passive structural jacket 500 comprises a passive filter circuit 10 configured to apply to an input a quadrature phase shift of a first polarity at the Larmor frequency of a first nucleus and a quadrature phase difference of a second polarity opposite the first polarity at the Larmor frequency of a second nucleus to control a first circular polarization to be opposite to a second circular polarization.

[0100] The system 200 may, for example, include a coil 204 1 ,204 3 Coil 204 2 ,204 4 The device may also include calibration circuitry that allows adjustment of the wearable system so that the sensor is properly aligned.

[0101] Thus, the system 200 provides a first output 112 via the balun 130. 1 a first coil 204 coupled to generate a first magnetic field 2 ,204 4 and a second output 112 via a balun 130. 1 a second coil 204 coupled to generate a second magnetic field 1 ,204 3 wherein, in use, the first magnetic field is oriented substantially in a first direction and the second magnetic field is oriented substantially in a second direction orthogonal to the first direction.

[0102] Inductive coupling to the target is a key indicator of the performance of an RF coil and is higher at higher frequencies or with larger RF coil dimensions. If the difference between the gyromagnetic ratios of the first and second nuclei is large, then there will be a large difference in the Larmor frequencies, which will be proportional to the applied static magnetic field B 0 As the size of the RF coil increases, the sensitivity of the first and second nuclei to a particular size of RF coil may therefore be different. For example, the sensitivity of the first and second nuclei to a particular size of RF coil may be 1 More than H 129 Xe is lower.

[0103] In some instances, it may be desirable to use different RF coils 204 for NMR of a first nucleus and NMR of a second nucleus.

[0104] The smaller the gyromagnetic ratio of the nuclei in NMR, the larger or more sensitive RF coil 204 can be used.

[0105] In FIG. 14, the larger coil 204 Xe but 129 The smaller coil 204 is used for Xe NMR. H but 1 Used in H NMR. This circuit implementation is for a receiver RF coil.

[0106] The amplifiers A1 and A2 are connected to the larger coil 204 which outputs one channel. Xe The smaller coil 204 is used in differential mode to provide a two-channel output. H are used in common mode.

[0107] The input to amplifier A1 is coil pair 204 H The input to amplifier A2 is connected to the first coil of coil pair 204. H The second coil of the coil pair 204 is connected to the second coil of the coil pair 204. H The first coil and coil pair 204 HThe second coil of the pair 204 is connected to a common voltage (e.g., ground). Thus, amplifier A1 H 204, the amplifier A2 measures the voltage across the first coil of the coil pair 204. H The voltage across the second coil of the amplifier A1 is measured. H The voltage V1 across the first coil of the balun 130 1 Output 132 via 1 The coil pair 204 measured by amplifier A2 is provided as H The voltage V2 across the second coil of the balun 130 2 Output 132 via 2 Supplied as.

[0108] Coil Pair 204 H is coil 204 Xe One of the inputs to amplifier A1 is coil 204. Xe One of the inputs to amplifier A2 is connected to coil 204, and the other input is connected to a common voltage (e.g., ground). Xe The other input is connected to a common voltage (e.g., ground). Thus, amplifier A1 Xe , and amplifier A2 measures the voltage across a portion of coil 204. Xe The voltage across the other part of the coil 204 is measured. These voltages are summed to form Xe The differential voltage across the balun 130 is obtained. 3 Output 132 via 3 Supplied as.

[0109] Amplifiers A1 and A2 are connected to one frequency (the lower Larmor frequency, e.g. 129 Larmor frequency of Xe) in differential mode, and other frequencies (higher Larmor frequencies, e.g. 1 It is a wideband amplifier that can operate in common mode for up to 100 MHz (the Larmor frequency of H).

[0110] The passive filter circuit 10 is also applicable to low power (less than 10 W) spectrometers, which can be used, for example, to monitor hyperpolarization.

[0111] Using spin exchange optical pumping (SEOP) 129 Hyperpolarization of Xe can be performed and the level of polarization can be monitored using a low power (low field) spectrometer. For example, it may be desirable to know when sufficient hyperpolarization has been achieved. It may also be desirable to measure the operational performance of the system to assess when adjustments or maintenance are required.

[0112] It would be desirable to have a hyperpolarization instrument configured to perform SEOP and also having a low field NMR system 200 that monitors the hyperpolarization.

[0113] It would be desirable to have a portable hyperpolarization device that is configured to perform SEOP and also has a low-field NMR system 200 that monitors the hyperpolarization.

[0114] In FIG. 15, the system 300 includes a static magnetic field B 0 The electromagnetic system 202 is configured to generate

[0115] The system includes a cell 302 for spin exchange optical pumping (SEOP). The cell contains a first nucleus (e.g. 129 Xe) as a gas, polarize at least a population of first nuclei, and then provide the polarized gas as an output gas. 1 H) NMR is, for example, H 2 0 are used to calibrate the yield (polarization) of this process.

[0116] Cell 302 itself is 11H is not accepted. There is a known amount of 1H (e.g., water or oil) inside the NMR system 200, but it is located outside the cell 302. The RF coil system 204 is used in quadrature to 129 Xe gas or 1 H) are measured one after the other at the same physical location of the RF coil configuration 204. 129 Xe gas) to the other sample ( 1 H).

[0117] As described above, the system 200 can be used to generate a first nucleus (e.g., 129 The polarization of Xe can be determined.

[0118] Typical operating magnetic field B 0 The maximum is 3mT, but it can be adjusted over a wide range. 129 For Xe, the Larmor frequency is 35.3 kHz (γ = 11.777 MHz / T). 1 At H, the Larmor frequency is 127.60 kHz (γ = 42.57 MHz / T).

[0119] The voltage induced in the coil 204 by the NMR signal is the magnetization (M 0 ), whereas the magnetization of hyperpolarized nuclei (M 0 ) is given as follows:

[0120]

number

[0121] where P is the percentage of magnetization and N is the atomic density.

[0122] A number of identical coils 204 may be arranged along the length of the cell so that the polarization distribution within the cell can be measured.

[0123] 1 H Temperature signal (at a certain temperature 1 The expected polarization of H) was used to generate the hyperpolarized129 Calibrate the Xe signal.

[0124] The system described above may be for nuclear magnetic resonance spectroscopy, nuclear magnetic resonance imaging, or nuclear magnetic resonance microscopy. In this specification, reference to an application may be replaced by a reference to a sample.

[0125] Nuclear magnetic resonance spectroscopy, nuclear magnetic resonance imaging, or nuclear magnetic resonance microscopy may be performed using the passive filter circuit 10, or the device 100, or the system 200. The passive filter circuit 10 allows for the simultaneous generation and / or detection of oppositely circularly polarized nuclear spins.

[0126] Nuclear magnetic resonance spectroscopy, nuclear magnetic resonance imaging, or nuclear magnetic resonance microscopy may be performed using simultaneous generation of oppositely circularly polarized nuclear spins in a first nucleus and a second nucleus and / or using simultaneous detection of oppositely circularly polarized nuclear spins in a first nucleus and a second nucleus.

[0127] The operation of the dual NMR system 200 is as follows: 129 XeRF coil 204 Xe This can be further improved by providing RF shielding for the coil 204. Xe The Q factor of the RF coil 204 is improved, which improves the inductive load. Xe The overall performance of the

[0128] However, the presence of RF shielding may affect the MRI system used for transmission. 1 Because the H transmitting coil cannot penetrate the RF shield, 1 It may adversely affect H NMR.

[0129] A specific first nucleus 1 The second nucleus is H 129Having described an embodiment with Xe in detail, we will now describe how these various devices 100, filters 10, circuits and systems can be adapted for use with various combinations of first and second nuclei having opposite polarity in the gyromagnetic ratio.

[0130] The phase rotation block 24 introduces a first phase shift Δφ 1 in a first direction at the Larmor frequency of the first nucleus, and at the same time, a second phase shift Δφ 2 in a first direction at the Larmor frequency of the second nucleus. For a given time delay, etc., the first phase shift is proportional to the Larmor frequency of the first nucleus and the second phase shift Δφ 2 is proportional to the Larmor frequency of the second nucleus and has the same polarity as the first phase shift.

[0131] Therefore, Δφ 1 / Δφ 2 =|γ 1 / γ 2 |=R, where γ 1 is the gyromagnetic ratio of the first nucleus, and γ 2 is the gyromagnetic ratio of the second nucleus. Therefore, Δφ 2 = Δφ 1 / |R|, where |R| is the gyromagnetic ratio of the first nucleus, γ 1 and the gyromagnetic ratio of the second nucleus γ 2 is the absolute value of the ratio.

[0132] The phase offset block 26 comprises circuitry configured to apply a relative phase offset θ between a first phase shift Δφ1 at the Larmor frequency of the first nucleus and a second phase shift Δφ2 at the Larmor frequency of the second nucleus, thereby generating a phase difference β between the first and second phase shifts after the offset. The second phase difference after the offset is Δφ 2 * If b, then β = Δφ 1 -Δφ 2 * b = Δφ 1 (1-b / |R|).

[0133] The phase difference β is summed across the N cascade filter modules to provide an output 14 having a quadrature phase change of a first polarity at the Larmor frequency of the first nucleus and a quadrature phase change of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus.

[0134] Therefore, the sum of the N relative phase differences β is a relative phase difference of 180°.

[0135] This is illustrated in FIG. 16A, which shows that the first nucleus 1 H, the second nucleus 129 This is the case for Xe, where N=3.

[0136] A general example is illustrated in FIG. 16B, where the first nucleus, γ 1 The second nucleus, γ 2 However, there are constraints that the gyromagnetic ratio of the first nucleus must be greater than that of the second nucleus and that the gyromagnetic ratios of the first and second nuclei must be of opposite polarity.

[0137] This means that the total phase difference (N*β) after N stages is N*Δφ 1 (1-b / |R|), which means it is equal to 180°.

[0138] For simplicity, the first phase shift Δφ 1 is set to +90°. Therefore, after N stages, the first phase shift Δφ 1 is equal to -90°, and the second phase shift Δφ 2 is equal to +90°. The second phase shift is Δφ 1 * b / |R| and after N stages is equal to +90°, so b=|R| / N. The second phase shift is Δφ 1|R|+θ and after N stages it is +π / 2, so θ=π / 2(1 / N-1 / (|R|)). In Figure 6, by selecting suitable values ​​for the shunt capacitors C1 and C2, a phase lag per stage of approximately 180° / 2N is introduced at the Larmor frequency of the second nucleus, and a phase lag per stage of approximately 90° is introduced at the Larmor frequency of the first nucleus.

[0139] 1 H and 129 For the combination of Xe, |R|=3.6, Δφ 1 =90° ≥ Δφ 2 = 90° / |R|=25°, and for N=3, θ=π / 2(1 / N-1 / (|R|))=5°(0.0873rad), b=|R| / N=1.2, so 129 For Xe, the phase shift after three stages is 3*(25°+5°)=90°.

[0140] 1 H and 15 For N combinations, |R|=9.866, Δφ 1 =90° ≥ Δφ 2 = 90° / |R| = 9.12°, and for N = 7, θ = π / 2(1 / N-1 / (|R|)) = 3.73° (0.651 rad), b = |R| / N = 1.41, so 15 For N, the phase shift after 7 stages is 7*(9.12°+3.73°)=90°.

[0141] 1 H and 17 For the combination of O, |R|=7.377, Δφ 1 =90° ≥ Δφ 2 = 90° / |R| = 12.2°, and for N = 7, θ = π / 2(1 / N-1 / (|R|)) = 0.66° (0.0115 rad), b = 1.054, so 17 For O, the phase shift after 7 stages is 7*(12.2°+0.66°)=90°.

[0142] It is preferable to keep θ to a small value.

[0143] It is preferable that the total phase difference after N stages (N*β) is equal to 180°, but it is sufficient if it is approximately 180°, and it is not necessarily required to be exactly 180°.

[0144] After N stages, the first phase shift Δφ 1 Although it may be preferable for the cumulative angle to be −90°, it is sufficient if the cumulative angle is approximately −90°, and it is not necessary for the cumulative angle to be exactly 90°.

[0145] After N stages, the second phase shift Δφ 2 Although it may be preferable for the cumulative angle to be +90°, it is sufficient if the cumulative angle is approximately +90°, and it is not necessary for the cumulative angle to be exactly +90°.

[0146] Where a structural feature is described, it may be replaced by a means that performs one or more of the functions of the structural feature, where that function or descriptions of those functions may be explicit or implicit.

[0147] In this specification, the word "comprise" is used in an inclusive rather than exclusive sense, i.e., any reference to "X comprising Y" means that X may comprise only one Y or may comprise two or more Y. If the exclusive sense of "comprise" is intended, this will be made clear in the context by referring to "comprising only one..." or by using "consisting."

[0148] In this description, various embodiments have been mentioned. The description of a feature or function in relation to an example indicates that the feature or function is present in that example. The use of the words "example," "for example," "can," or "may" in a sentence, whether or not explicitly stated, means that such feature or function is present in at least the described example, whether or not it is described as an example, and may, but not necessarily, be present in some or all of the other examples. Thus, "example," "for example," "can," or "may" refers to a particular example of a class of examples. A property of that example may be a property of that example only, or of the class, or of a subclass of that class that includes some but not all of the examples in the class. Thus, a feature described with reference to one example but not another example is implicitly disclosed as usable in that other example, if possible, as part of a working combination, but not necessarily for use in that other example.

[0149] Although the embodiments have been described in the preceding paragraphs with reference to various examples, it will be appreciated that modifications of the examples given are possible without departing from the scope of the claims.

[0150] The features set out in the foregoing description may be used in combinations other than those explicitly stated above.

[0151] Although functions have been described with reference to particular features, those functions may be performed by other features, whether or not described.

[0152] Although features have been described with reference to particular embodiments, those features may also be present in other embodiments whether or not they are described.

[0153] In this specification, the words "a" or "the" are used in an inclusive rather than exclusive sense. That is, any reference to "X with a / the Y" means that X may have only one Y or may have two or more Y, unless the context clearly indicates otherwise. If "a" or "the" is intended to be used in an exclusive sense, this will be made clear in the context. In some situations, the use of "at least one" or "one or more" may be used to emphasize an inclusive sense, but the absence of these words should not be taken to imply any exclusive sense.

[0154] The presence of a feature (or combination of features) in a claim is a reference both to the feature (or combination of features) per se and also to features which achieve substantially the same technical effect (equivalent features). Such equivalent features include, for example, features which are modifications and achieve substantially the same result in substantially the same way. Such equivalent features include, for example, features which perform substantially the same function in substantially the same way to achieve substantially the same result.

[0155] In this description, various embodiments have been referred to using adjectives or adjectival phrases that describe features of each embodiment. Describing a feature in connection with one embodiment in this manner means that the feature is present in some embodiments exactly as described and in other embodiments substantially as described.

[0156] While an attempt has been made in the foregoing specification to focus on features which are believed to be important, it should be understood that applicants may seek protection in the claims with respect to any patentable feature or combination of features referred to in this specification and / or shown in the drawings, whether or not emphasized.

Claims

1. A passive filter circuit that performs simultaneous dual nuclear magnetic resonance orthogonal transmission and reception, configured to apply to an input an in-phase quadrature phase shift at the Larmor frequency of a first nucleus and an in-phase quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of a second nucleus.

2. The passive filter circuit according to claim 1, comprising at least a second-order filter.

3. The passive filter circuit according to claim 1, comprising a plurality of cascaded filter modules.

4. The passive filter circuit according to claim 3, wherein each cascaded filter module is the same.

5. Each cascaded filter module is configured to provide a relative phase change such that, as a result of summing over the entire passive filter circuit, the output has an in-phase quadrature phase change of a first polarity at the Larmor frequency of the first nucleus and an in-phase quadrature phase change of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus. The passive filter circuit according to claim 3.

6. The passive filter circuit according to claim 5, wherein each module comprises at least a second-order filter.

7. Each module comprises a circuit configuration configured to apply a first phase shift in a first direction at the Larmor frequency of the first nucleus, proportional to the Larmor frequency of the first nucleus, and a second phase shift in the first direction at the Larmor frequency of the second nucleus, proportional to the Larmor frequency of the second nucleus, a circuit configuration configured to generate a phase difference between the first phase shift at the Larmor frequency of the first nucleus and the second phase shift at the Larmor frequency of the second nucleus by applying an offset between the first phase shift and the second phase shift, the phase difference being used to supply the output, The output has an in-phase quadrature phase change of a first polarity at the Larmor frequency of the first nucleus and an in-phase quadrature phase change of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus. The passive filter circuit according to claim 5.

8. The offset between the first phase shift at the Larmor frequency of the first nucleus and the second phase shift at the Larmor frequency of the second nucleus generates a phase difference between the first phase shift and the second phase shift after the offset, and multiplying the phase difference by the total number can obtain a final 90° phase difference. The passive filter circuit according to claim 4.

9. Configured to control the change in the number of a plurality of cascade filter modules and / or to control the change in the element values of the plurality of cascade filter modules for various combinations of the first nucleus and the second nucleus. The passive filter circuit according to claim 3.

10. There are three cascade filter modules, and each filter module １ introduces a +90-degree relative phase change at the Larmor frequency of the H nucleus, １２９ The passive filter circuit according to claim 3, which introduces a -30-degree relative phase change at the Larmor frequency of the Xe nucleus.

11. Each module said １ apply a -90° phase shift at the Larmor frequency of the H nucleus, and said １２９ a circuit configuration configured to apply a phase shift of approximately -25° at the Larmor frequency of the Xe nucleus, and The above-mentioned １ Compared with the Larmor frequency of the H nucleus, the above-mentioned １２９ The passive filter circuit according to claim 10, comprising a circuit configuration configured to apply an offset of a phase shift of approximately -5° at the Larmor frequency of the Xe nucleus.

12. An apparatus for performing simultaneous double nuclear magnetic resonance, One or more passive filter circuits according to claim 1, configured to supply a first output signal having a quadrature phase difference of a first polarity at the Larmor frequency of the first nucleus and a second output signal having a quadrature phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus. An apparatus comprising a passive filter circuit.

13. A quadrature phase hybrid circuit configured to supply a first output signal to a first passive filter circuit and a second output signal to a second passive filter circuit, wherein the first output signal and the second output signal have a quadrature phase difference at both the Larmor frequency of the first nucleus and the Larmor frequency of the second nucleus, and one of the first and second passive filter circuits is the circuit according to claim 1. Comprising a quadrature phase hybrid circuit. Or, A quadrature phase hybrid circuit configured to supply a first output signal and a second output signal, wherein the first output signal and the second output signal have a quadrature phase difference with opposite polarities at the Larmor frequency of the first nucleus and the Larmor frequency of the second nucleus, and the quadrature phase hybrid circuit is connected between the first output and the second output and includes at least one passive filter circuit for supplying the first output signal and the second output signal. An apparatus according to claim 12, comprising a plurality of passive filter circuits according to claim 1.

14. Configured as a transmitter for simultaneous double nuclear magnetic resonance and / or as a receiver for simultaneous double nuclear magnetic resonance. The apparatus according to claim 12.

15. An apparatus as a polarization device according to claim 12, comprising a first coil configuration connected to a first output signal having the quadrature phase difference of the first polarity at the Larmor frequency of the first atomic nucleus for generating a first magnetic field, and a second output signal having the quadrature phase difference of the second polarity opposite to the first polarity at the Larmor frequency of the second atomic nucleus for generating a second magnetic field; wherein one of the first magnetic field and the second magnetic field is a right-handed circular polarization, and the other of the first magnetic field and the second magnetic field is a left-handed circular polarization.

16. The apparatus according to claim 15, wherein the first coil configuration is configured as a jacket worn by a human subject.

17. The apparatus according to claim 15, wherein the first coil configuration includes a first coil connected to the first output signal to generate the first magnetic field and a second coil connected to the second output signal to generate the second magnetic field, and in use, the first magnetic field is substantially directed in a first direction, and the second magnetic field is substantially directed in a second direction orthogonal to the first direction.

18. A system for performing simultaneous double nuclear magnetic resonance on the first atomic nucleus and the second atomic nucleus, comprising the passive filter circuit according to claim 1 and the apparatus according to claim 12, wherein the first atomic nucleus and the second atomic nucleus have opposite polarities of magnetic gyromagnetic ratios.

19. The system according to claim 18, wherein the system is configured to perform simultaneous double nuclear magnetic resonance on the first atomic nucleus and the second atomic nucleus without using time-division switching.

20. The first nucleus is １ H, and the second nucleus is hyperpolarized １２９ Xe, and the system includes a hyperpolarization device that generates the hyperpolarized １２９ Xe, the system according to claim 18.

21. The system according to claim 18, configured to perform nuclear magnetic resonance spectroscopy, nuclear magnetic resonance imaging, or nuclear magnetic resonance microscopy.

22. A method of performing nuclear magnetic resonance spectroscopy, nuclear magnetic resonance imaging, or nuclear magnetic resonance microscopy, the method using the passive filter circuit according to any one of claims 1 to 11, or the apparatus according to any one of claims 12 to 17, or the system according to any one of claims 18 to 21, wherein the passive filter circuit enables simultaneous generation and / or detection of circularly polarized nuclear spins with opposite polarities.

23. A method for performing nuclear magnetic resonance spectroscopy, nuclear magnetic resonance imaging, or nuclear magnetic resonance microscopy using simultaneous generation of circularly polarized nuclear spins with opposite polarities in a first nucleus and a second nucleus, and / or using simultaneous detection of circularly polarized nuclear spins with opposite polarities in the first nucleus and the second nucleus.

24. A passive structure jacket for performing dual nuclear magnetic resonance orthogonal transmission and reception on an object to be applied, comprising a circuit configuration configured to generate and detect a first magnetic field having a first circular polarization at the Larmor frequency of a first nucleus and to generate and detect a second magnetic field having a second circular polarization at the Larmor frequency of the first nucleus, wherein in the object to be applied, the first circular polarization is opposite to the second polarization.

25. Comprising at least a first coil pair for generating a first component of a transverse magnetic field and at least a second coil pair for generating a second component of the transverse magnetic field, and means for calibrating the alignment of the first coil pair and / or the alignment of the second coil pair. And / or A passive filter circuit configured to apply, as an input, an orthogonal phase shift of a first polarity at the Larmor frequency of a first nucleus and an orthogonal phase difference of a second polarity opposite to the first polarity at the Larmor frequency of a second nucleus, and to control the first circular polarization to be opposite to the second circular polarization. The passive structure jacket according to claim 24.

26. A method for performing nuclear magnetic resonance spectroscopy, nuclear magnetic resonance imaging, or nuclear magnetic resonance microscopy, which is a method using simultaneous generation of circularly polarized nuclear spins with opposite polarities in a first nucleus and a second nucleus, wherein the nuclear spin of the first nucleus has an orthogonal phase difference of a first polarity at the Larmor frequency of the first nucleus, the nuclear spin of the second nucleus has an orthogonal phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus, and / or a method using simultaneous detection of circularly polarized nuclear spins with opposite polarities in a first nucleus and a second nucleus, wherein the nuclear spin of the first nucleus has an orthogonal phase difference of a first polarity at the Larmor frequency of the first nucleus, and the nuclear spin of the second nucleus has an orthogonal phase difference of a second polarity opposite to the first polarity at the Larmor frequency of the second nucleus.

27. A passive structure jacket that performs double nuclear magnetic resonance orthogonal transmission and reception on an object to be applied, comprising a circuit configuration configured to generate and detect a first magnetic field having a first circular polarization at the Larmor frequency of a first nucleus and to generate and detect a second magnetic field having a second circular polarization at the Larmor frequency of the first nucleus, wherein the first circular polarization has a first direction of rotation, and the first direction of rotation is opposite to the second direction of rotation of the second polarization in the object to be applied. Passive structure jacket.

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