JPH04346088A - Measuring apparatus of triple magnetic resonance - Google Patents

Abstract

PURPOSE:To acquire more abundant information of analysis by disposing three coils so that a magnetic field generated by each one coil intersects the one of another perpendicularly and by connecting each coil to one of high-frequency power sources being independent of one another. CONSTITUTION:Three exciting coils 1, 2 and 3 are disposed so that the respective axes intersect one another perpendicularly, and these three exciting coils 1, 2 and 3 are connected to high-frequency power sources 4, 5 and 6 being different in an oscillation frequency from one another so that a static magnetic field is impressed in one direction intersecting the axes of these exciting coils 1, 2 and 3 at equal angles. The three high-frequency power sources 4, 5 and 6 are not subjected to induction from the other coils respectively, the frequencies thereof can be changed independently of one another, no mutual interference occurs in measurement of a point of magnetic resonance of a sample, and measurement of triple resonance is enabled. Thus, acquisition of more abundant information on analysis is enabled in measurement of the triple resonance.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a high-frequency magnetic field generating coil used in a magnetic resonance measurement apparatus.

0002

[Prior Art] When a sample is placed in a field and a high-frequency magnetic field orthogonal to it is applied, and the strength of the static magnetic field is changed, the sample absorbs energy from the high-frequency magnetic field at a certain strength, and electromagnetic waves of the same frequency The magnetic resonance of the sample is measured by detecting the radiated electromagnetic waves using a coil in a direction different from that of the coil that applies the high-frequency magnetic field. Perform analysis. When applying a magnetic field of a single frequency to a sample while changing the static magnetic field strength, the information obtained is information about the transition of sample molecules from the ground state, but it is also information about the transition from a certain excited state. The appearance also provides useful information for analysis. For this purpose, it is necessary to simultaneously apply two or more magnetic fields of different frequencies to the sample and measure the magnetic resonance absorption capacity. For this reason, a magnetic resonance measurement method has conventionally been used in which magnetic fields of two frequencies are simultaneously applied by applying magnetic fields of mutually independent frequencies in two orthogonal directions.

As mentioned above, magnetic resonance measurements have traditionally been performed in which magnetic fields of two different frequencies are applied to a sample.
By applying magnetic fields of three different frequencies, it is possible to obtain even more analytical information. However, when trying to apply three types of high-frequency magnetic fields simultaneously, the following problem occurs. That is, by arranging two types of high-frequency magnetic fields and two high-frequency coils so as to be orthogonal to each other, mutual coupling can be minimized and mutual interference in measurement can be minimized. However, when a coil is arranged to apply a magnetic field of a third frequency, this third coil causes mutual coupling with either of the other two coils. By devising the electric circuit, it is possible to have two resonance points and put two frequencies on one coil, applying magnetic fields of three different frequencies in total. However, this method limits the degree of freedom in selecting the third frequency, and is extremely unsatisfactory in terms of obtaining more analytical information.

0004

[Problems to be Solved by the Invention] The present invention provides a triple magnetic field generator that applies three types of magnetic fields of frequencies completely independently selected to each other to a sample in magnetic resonance measurement, and can perform triple magnetic resonance measurements without mutual interference. This is what we are trying to provide.

[0005]

[Means for Solving the Problems] Three coils were arranged so that the magnetic fields generated by the respective coils were orthogonal to each other, and each coil was connected to an independent high-frequency power source.

[0006]

[Operation] When two annular coils are placed with their coil surfaces perpendicular to each other, the coil surface of one coil is in the magnetic field created by the other coil, and the coil surface is parallel to that magnetic field. , the magnetic field does not interlink with the coils, and the mutual coupling between the two coils is zero. The fact that the three coils can be arranged in the relationship described above with respect to each other is based on the fact that the three straight lines can be orthogonal in space. In the present invention, since the three coils are arranged in this way, each of the three high-frequency power sources is not affected by the induction effect from the other coils and can change the frequency independently of each other, making it possible to measure the magnetic resonance point of the sample. There is no mutual interference in this case, making it possible to measure triple resonance.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The three excitation coils 1, 2, and 3 shown in FIG. 1 are combined as shown in FIG. 2 while maintaining the orientation shown in the drawing, and each coil is connected to a respective high-frequency power source 4, 5, and 6. coil 1
forms a magnetic field in the x direction, coil 2 forms a magnetic field in the y direction, coil 3 forms a magnetic field in the z direction, and each coil has a pair of square frame parts 11, 12, 21, 22 and 31, 32. , each coil connects these pair of frame parts so that current flows as shown by the arrow in the figure.

As shown in FIG. 1, each frame of the excitation coils 1, 2, and 3 has one corner cut off and joined diagonally, and when the three coils are combined as shown in FIG. A triangular gap is created between a pair of opposing vertices of the cube that the frame constitutes. This gap is provided through which the sample can be inserted along one diagonal.

In magnetic resonance measurement, only the component orthogonal to the static magnetic field Bo in which the sample is placed in each high-frequency magnetic field is effective for measurement, so the static magnetic field is composed of a pair of opposing vertices with a gap as shown by the arrow Bo in FIG. The coils are formed in the direction of a diagonal line different from the diagonal line, so that each coil has an equal relationship with respect to the static magnetic field Bo.

7, 8, and 9 are detection coils, respectively, and the coil 7
The axis of is a straight line connecting the midpoints of the two opposing sides a and b of the cube formed by the frame in Figure 2, and is perpendicular to the magnetic field created by the coil 1, so it is not subject to the inductive action from the coil 1. By connecting the detection circuit 11 to the coil 7 via a tuning circuit 10 tuned to the oscillation frequency F1 of the power source 4 of the coil 1, resonance of the sample with respect to the electromagnetic wave of the frequency Fx can be detected. Tuning circuits 12, 13 and detection circuits 14, 15 are similarly connected to other detection coils 8, 9, and resonance of the sample with respect to oscillation frequencies F2, F3 of power supplies 5, 6 is detected.

[0011]

[Effects of the Invention] According to the present invention, the three frequencies of the high-frequency magnetic field applied to the sample can be set completely independently and applied to the sample symmetrically with respect to each other. It becomes possible to obtain a wealth of analytical information.

[Brief explanation of drawings]

FIG. 1 is a perspective view of three excitation coils separated in an embodiment of the present invention.

FIG. 2 is a perspective view of the entire embodiment. 1, 2, 3 Excitation coils 4, 5 orthogonal to each other
, 6 High frequency power supplies 7, 8, connected to each coil
9 Detection coils 10, 11, 12 Tuned circuits 13, 14, 15 Detection circuit

Claims (1)

[Claims] Three excitation coils are arranged with their respective axes perpendicular to each other, and these three excitation coils are connected to high-frequency power sources with different oscillation frequencies, and a static magnetic field is applied in one direction that intersects the axis of each excitation coil at an equal angle. A triplex magnetic resonance measuring device characterized in that it applies .