JPS63266804A - Magnetic field generator - Google Patents
Magnetic field generatorInfo
- Publication number
- JPS63266804A JPS63266804A JP62101291A JP10129187A JPS63266804A JP S63266804 A JPS63266804 A JP S63266804A JP 62101291 A JP62101291 A JP 62101291A JP 10129187 A JP10129187 A JP 10129187A JP S63266804 A JPS63266804 A JP S63266804A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- space
- permanent magnet
- main pole
- magnetic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000009826 distribution Methods 0.000 claims abstract description 19
- 230000004907 flux Effects 0.000 claims abstract description 12
- 230000002093 peripheral effect Effects 0.000 claims abstract description 7
- 238000005259 measurement Methods 0.000 abstract description 7
- 238000009827 uniform distribution Methods 0.000 abstract 2
- 238000000034 method Methods 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229910052761 rare earth metal Inorganic materials 0.000 description 3
- 150000002910 rare earth metals Chemical class 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
- 238000013421 nuclear magnetic resonance imaging Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- ZDVYABSQRRRIOJ-UHFFFAOYSA-N boron;iron Chemical compound [Fe]#B ZDVYABSQRRRIOJ-UHFFFAOYSA-N 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 239000007799 cork Substances 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000000877 morphologic effect Effects 0.000 description 1
- 229910001172 neodymium magnet Inorganic materials 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 210000004872 soft tissue Anatomy 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 210000001519 tissue Anatomy 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Landscapes
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、核磁気共鳴映像法を利用した画像診断装置等
に用いられる、所定区域全体にわたって均一な磁界を必
要とする磁界発生装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic field generating device that is used in an image diagnostic apparatus using nuclear magnetic resonance imaging, etc., and which requires a uniform magnetic field over a predetermined area.
画像処理を用いた形態診断用断層装置として、核磁気共
鳴映像法による画像診断装置が開発され、その医学的利
用価値が注目を集めている。An image diagnostic apparatus using nuclear magnetic resonance imaging has been developed as a tomographic apparatus for morphological diagnosis using image processing, and its medical utility value is attracting attention.
この種の装置は、生体の大部分を構成する水素原子核の
磁気共鳴現象が組織によって異なることを利用して、生
体の一部又は全体を磁界中に挿入して、生体軟部組織を
画像化するもので、共鳴の強さや共鳴の時間的変化の大
きさを画像上の濃淡として与えている。This type of device takes advantage of the fact that the magnetic resonance phenomenon of hydrogen atoms, which make up most of the living body, differs depending on the tissue, and images the soft tissues of the living body by inserting part or all of the living body into a magnetic field. The strength of the resonance and the magnitude of the change in resonance over time are expressed as shading on the image.
上記の画像診断装置によって得られた画像は、磁界の強
さやその分布によって変化する。現在の技術では、１゜
５ Ｔｅ５ｌａ（］５，０ＯＯＧ）以下の磁界では、磁
界が強い程画質が良いことがわかっている。ただし磁場
が強い程装置が高価となりかつ保守に難を要すため、現
状では画像処理技術の点から比較的低磁場（０，１５〜
０．２ Ｔｅ５ｌａ）での画像向」二が検討されている
。Images obtained by the above-mentioned image diagnostic apparatus change depending on the strength of the magnetic field and its distribution. With current technology, it is known that in a magnetic field of 1°5 Te5la (]5,0OOG) or less, the stronger the magnetic field, the better the image quality. However, the stronger the magnetic field, the more expensive the device becomes and the more difficult it is to maintain.Currently, from the viewpoint of image processing technology, the magnetic field is relatively low (0.15~
An image orientation of 0.2Te5la) is being considered.
上記の装置における磁界発生方式として、現在実用化さ
れているのは、常伝導磁石方式と超伝導磁石方式である
。しかるに常伝導磁石方式は、電力消費量が大でかつ冷
却水も必要となるので運転経費が高くなるという難点が
ある。超伝導磁石方式は、０．３Ｔｅｓｌａ以上の高磁
場が簡単に得られるため画質は良いが、冷媒として高価
なＨｅガスやＮ２ガスを用いるので運転経費は前者より
も高くなり、又漏洩磁界が大であるため広大な設置スペ
ースを必要とするという難点がある。As magnetic field generation methods for the above-mentioned apparatus, the methods currently in practical use are a normal conduction magnet method and a superconducting magnet method. However, the normal conduction magnet method has the disadvantage that it consumes a large amount of power and requires cooling water, resulting in high operating costs. The superconducting magnet method has good image quality because it can easily obtain a high magnetic field of 0.3 Tesla or more, but since it uses expensive He gas or N2 gas as a coolant, the operating cost is higher than the former, and the leakage magnetic field is large. Therefore, it has the disadvantage that it requires a large installation space.
これらの難点を解消し、保守を安価かつ容易に行なえる
ようにするため磁界発生装置の永久磁石化が検討されて
いる。In order to solve these difficulties and make maintenance inexpensive and easy, the use of permanent magnets in magnetic field generating devices is being considered.
例えば、特開昭６０−７６１０４号は、磁気回路の小型
化及び軽量化のために、最大エネルギーｉが３０ＭＧＯ
ｅのＲ−Ｐｅ−Ｂ系永久磁石を使用することを開示して
いる。また、特開昭６０−２３９００５号は、磁界発生
装置の空隙に均一な磁界を発生するために、主磁界を発
生する永久磁石と同一磁化方向を有する補助永久磁石を
、前記永久磁石内に設けて、空隙への磁束発生量を調整
、均一化することを開示している。また、特開昭６１−
２０３６０５号は、方形筒状の継鉄の互いに平行な内壁
面に突設されたＮ、Ｓ一対の磁極（永久磁石ブロック）
の表面に密接して、高透磁率低保磁力の軟質磁性材より
なる板状の磁場均等化手段を設けることを開示している
。For example, in JP-A-60-76104, the maximum energy i is 30 MGO in order to reduce the size and weight of the magnetic circuit.
discloses the use of an R-Pe-B permanent magnet of e. Further, in JP-A-60-239005, in order to generate a uniform magnetic field in the air gap of a magnetic field generating device, an auxiliary permanent magnet having the same magnetization direction as the permanent magnet that generates the main magnetic field is provided inside the permanent magnet. It is disclosed that the amount of magnetic flux generated in the air gap is adjusted and made uniform. Also, JP-A-61-
No. 203605 is a pair of N and S magnetic poles (permanent magnet block) protruding from the mutually parallel inner wall surfaces of a rectangular cylindrical yoke.
It is disclosed that a plate-shaped magnetic field equalizing means made of a soft magnetic material with high magnetic permeability and low coercive force is provided in close contact with the surface of the magnetic field.
上記の画像診断装置においては、共鳴する周波数領域を
せばめて高画質を得るために所定区域全体にわたって均
一な磁界分布、具体的には１Ｏ−５（数１０ｐｐｍ）以
下の均一性が要求される。そのため永久磁石方式、特に
軸方向に磁化した永久磁石を１対向させる形式の磁界発
生装置においては、上述したように主磁界発生用永久磁
石の内部に補助永久磁石を移動自在に設けることなどが
提案されている。In the above-described image diagnostic apparatus, in order to obtain high image quality by narrowing the resonant frequency region, a uniform magnetic field distribution is required over the entire predetermined area, specifically, a uniformity of 10-5 (several tens of ppm) or less. Therefore, in a permanent magnet type magnetic field generation device, especially one in which one permanent magnet magnetized in the axial direction is placed facing each other, it is proposed that an auxiliary permanent magnet be movably provided inside the main magnetic field generation permanent magnet as described above. has been done.
ところがラジアル界磁型の永久磁石方式の場合、製造条
件のバラツキなどにより上、下の永久磁石の磁気特性を
一致させることは極めて困難であり、上述した磁界調整
手段を付加しても、磁界の不均一度を補正しきれない、
あるいは、補正に極めて手間がかかるなどの問題があっ
た。すなわち本発明の対象とするラジアル界磁型の磁界
発生装置においては、所定区域での磁界分布を均一にさ
せることが困難であった。However, in the case of a radial field type permanent magnet system, it is extremely difficult to match the magnetic properties of the upper and lower permanent magnets due to variations in manufacturing conditions, and even with the addition of the magnetic field adjustment means described above, the magnetic field The degree of non-uniformity cannot be fully corrected.
Another problem is that it takes a lot of time to correct. That is, in the radial field type magnetic field generation device that is the object of the present invention, it is difficult to make the magnetic field distribution uniform in a predetermined area.
したがって、本発明の目的は、所定区域における均一な
磁界分布が容易に得られる磁界発生装置を提供する□こ
とである。Therefore, an object of the present invention is to provide a magnetic field generating device that can easily obtain a uniform magnetic field distribution in a predetermined area.
本発明は、同一軸線上に空間を挟んで対向する、半径方
向に磁化された一対め円筒状永久磁石と、永久磁石の内
側に設置された、永久磁石の磁束を空間の所定区域に集
束させる略円板状の一対の主ポールピースと、永久磁石
同志を磁気的に結合させるヨークとを有する磁界発生装
置において、主ポールピースは中央部と外周部とが中間
部よりも厚肉に形成されており、かつ、中間部の厚さは
所定区域における軸と直角方向の磁界分布が実質的に均
一であるような厚さを有することを特徴とする。The present invention includes a pair of radially magnetized cylindrical permanent magnets facing each other on the same axis with a space in between, and a pair of permanent magnets installed inside the permanent magnets to focus the magnetic flux of the permanent magnets in a predetermined area of the space. In a magnetic field generating device that has a pair of approximately disc-shaped main pole pieces and a yoke that magnetically couples permanent magnets, the main pole piece has a center portion and an outer peripheral portion that are thicker than an intermediate portion. and the thickness of the intermediate portion is such that the magnetic field distribution in the direction perpendicular to the axis in the predetermined area is substantially uniform.
以下本発明の詳細を図面により説明する。 The details of the present invention will be explained below with reference to the drawings.
第１図は本発明の一実施例に係るラジアル界磁型の磁界
発生装置の断面図である。FIG. 1 is a sectional view of a radial field type magnetic field generator according to an embodiment of the present invention.
磁界発生装置１は、同一軸線上に空間３を挟んで対向す
る円筒状の一対の永久磁石２を備えている。一対の永久
磁石２の外周にコーク４を設け、ヨーク４．４間を支柱
８で磁気的に結合し、各永久磁石の内周に主ポールピー
ス５を嵌合して磁気回路を形成することにより、空間３
の中央部の測定空間３ａでは永久磁石２の軸線方向（第
２図矢印Ａ）に磁界が生じるようになっている。主ポー
ルピース５は円板状であって、その外周部に設けた複数
個のねじ６によって永久磁石２の内周に同心状に固定部
材７を介して取付けられる。主ポールピース５は、中央
部５ａが厚肉に形成され、外周部５Ｃが段状突部に形成
されて空間３の被検体の測定空間３ａに永久磁石から発
生した磁束（第１図に矢印で示す）を有効に集中できる
ようになっている。中央部５ａと外周部５Ｃとの間の中
間部５ｂは全体にわたって実質的に均一な厚さｔを有し
ている。The magnetic field generator 1 includes a pair of cylindrical permanent magnets 2 facing each other on the same axis with a space 3 in between. A cork 4 is provided on the outer periphery of a pair of permanent magnets 2, the yokes 4 and 4 are magnetically coupled with a support 8, and a main pole piece 5 is fitted on the inner periphery of each permanent magnet to form a magnetic circuit. Therefore, space 3
A magnetic field is generated in the axial direction of the permanent magnet 2 (arrow A in FIG. 2) in the measurement space 3a at the center of the magnet. The main pole piece 5 is disk-shaped and is attached concentrically to the inner circumference of the permanent magnet 2 via a fixing member 7 by a plurality of screws 6 provided on its outer circumference. The main pole piece 5 has a thick center part 5a, and a stepped outer peripheral part 5C, so that the magnetic flux generated from the permanent magnet in the measurement space 3a of the test object in the space 3 (see the arrow in FIG. (indicated by) can now concentrate effectively. The intermediate portion 5b between the central portion 5a and the outer peripheral portion 5C has a substantially uniform thickness t throughout.
上記の装置において、永久磁石２は、測定空間内に１０
００〜３０００Ｇの磁界を発生させるために、フェライ
ト磁石、希土類コバルト磁石あるいは希土類・鉄・ボロ
ン磁石のような材料から製作される。In the above device, the permanent magnet 2 is placed in the measurement space at 10
In order to generate a magnetic field of 0.00 to 3000 G, it is fabricated from materials such as ferrite magnets, rare earth cobalt magnets, or rare earth iron boron magnets.
これらの磁石材料の内では、できるだけ少量の材料で上
記のような強さの磁界を得るために、起磁力の大きな希
土類・鉄・ボロン磁石が好適である。Among these magnet materials, rare earth, iron, and boron magnets with large magnetomotive force are preferred in order to obtain a magnetic field of the above strength with as little material as possible.
また永久磁石２は、その磁化方向（第１図に矢印Ｍで示
す）すべて半径方向を向いており、下側の永久磁石２の
Ｎ極はヨーク４を介して上側の永久磁石２のＳ極と磁気
的に結合され、第１図に矢印で示すように上側の永久磁
石２のＮ極から出る磁束は主ポールピース５を通り、空
間５を通して主ポールピース５を通り、さらに下側の永
久磁石２のＳ極に戻るようになっている。The magnetization directions (indicated by arrows M in FIG. 1) of the permanent magnets 2 are all oriented in the radial direction, and the N pole of the lower permanent magnet 2 is connected to the S pole of the upper permanent magnet 2 via the yoke 4. As shown by the arrow in FIG. It returns to the S pole of magnet 2.
ヨーク４、主ポールピース５、固定部材７及び支柱８は
、軟鉄、鋼等の軟磁性材料で形成される。The yoke 4, the main pole piece 5, the fixing member 7, and the support column 8 are made of a soft magnetic material such as soft iron or steel.
本発明者は上記の磁界発生装置について種々検討した結
果、主ポールピースの厚さ、特にその中間部の厚さｔを
適切なものとすることにより、空間の所定区域での磁界
強度と磁界分布の均一性を望ましいものとじうろことが
わかった。As a result of various studies on the above-mentioned magnetic field generating device, the inventor of the present invention has determined that the thickness of the main pole piece, especially the thickness t of the intermediate portion thereof, can be appropriately adjusted to improve the magnetic field strength and magnetic field distribution in a predetermined area of the space. It was found that uniformity is desirable.
すなわち主ポールピースの厚さく以下単にｔということ
もある）が小さい程磁気抵抗が大きくなる、即ち、磁束
が通りにくくなるので、磁界強度が低下する。またこの
ようなラジアル界磁型の磁気回路の場合、Ｘ軸方向の磁
界分布をとると、ｔが小さい程測定空間の中心（第１図
にＣで示す）における磁界強度が低下し、均一な磁界分
布は得にくくなる。一方ｔが厚くなる程磁気抵抗は減少
するので、磁界強度は高くなる。ただしｔがある値まで
達すると磁界強度は飽和するので、ｔをむやみに大きく
しても意味はない。またもが厚ずぎると、Ｘ軸方向の磁
界分布をのると、上記とは逆に測定空間の中心における
磁界強度か大きくなって、この場合も均一な磁界分布は
得られなくなる。That is, the smaller the thickness of the main pole piece (hereinafter also simply referred to as t), the greater the magnetic resistance becomes, that is, the more difficult it becomes for magnetic flux to pass through, resulting in a decrease in magnetic field strength. In addition, in the case of such a radial field type magnetic circuit, when taking the magnetic field distribution in the X-axis direction, the smaller t is, the lower the magnetic field strength at the center of the measurement space (indicated by C in Figure 1) is The magnetic field distribution becomes difficult to obtain. On the other hand, as t becomes thicker, the magnetic resistance decreases, so the magnetic field strength increases. However, since the magnetic field strength is saturated when t reaches a certain value, there is no point in increasing t unnecessarily. If the thickness is too large, the magnetic field strength at the center of the measurement space increases, contrary to the above, when looking at the magnetic field distribution in the X-axis direction, and even in this case, a uniform magnetic field distribution cannot be obtained.
このような理由により、主ポールピースの厚さｔを適当
な値に定めることにより高い磁界強度と良好な磁界の均
一性が得られる。具体的なｔの値は、磁石材質や各部の
寸法等に応じて適宜定めればよい。For these reasons, high magnetic field strength and good magnetic field uniformity can be obtained by setting the thickness t of the main pole piece to an appropriate value. The specific value of t may be determined as appropriate depending on the magnet material, the dimensions of each part, etc.
次に上記実施例の磁界発生装置を使用し、主ポールピー
スの厚さを変更することにより、空間３の作用空間３ａ
およびその周囲での中心Ｃを含みかつ軸と直交する方向
の磁束密度を測定した。その結果を第３図に示す。ここ
で永久磁石は、Ｎｄ−Ｆｅ−Ｂ磁石（Ｂｒ＝１２１００
Ｇ 、 ｂｌｌｃ＝１１００００ｅ、 （ＢＨ）ｌＮ＝
３５ ＭＧＯｅ）で製作し、その外径は９６０ｍｍ、内
径８０４ ｍｍ、厚さ１９８龍とし、一対の永久磁石間
距離は４８０＋＋１、主ポールピースは、外径７０８１
■、中央部の外径及び厚さは４５０ｍｍ及び１５酊、外
周部の厚さ９鰭で、中間部の厚さを６〜１５１まで変化
させた。また測定空間は半径１５０ｍｍの球体を想定し
た。Next, by using the magnetic field generating device of the above embodiment and changing the thickness of the main pole piece, the working space 3a of the space 3 is
The magnetic flux density in the direction including the center C and perpendicular to the axis was measured. The results are shown in FIG. Here, the permanent magnet is a Nd-Fe-B magnet (Br=12100
G, bllc=110000e, (BH)lN=
35 MGOe), its outer diameter is 960 mm, inner diameter is 804 mm, thickness is 198 mm, the distance between a pair of permanent magnets is 480++1, and the main pole piece has an outer diameter of 7081 mm.
(2) The outer diameter and thickness of the central part were 450 mm and 15 mm, the outer circumferential part had a thickness of 9 fins, and the thickness of the middle part was varied from 6 to 15 mm. Furthermore, the measurement space was assumed to be a sphere with a radius of 150 mm.
第２図から、ｔが６１１１では１５００ Ｇ以下の磁束
密度（Ｂｇ）Ｌか得られず、又その分布も不均一なもの
であるが、ｔが厚くなるに従って磁束密度が向上しかつ
磁界分布の均一性も改善され、特にｔが１５顛の時に磁
束密度が最も高くなりしかも磁界分布のバラツキを実質
的に無くせることがわがる。なお第３図では示していな
いが、ｔが１５龍を越えると磁気的に飽和し、磁束密度
の向上はなく、又、均一な磁界分布を得ることができな
かった。From Figure 2, when t is 6111, a magnetic flux density (Bg)L of less than 1500 G cannot be obtained, and its distribution is non-uniform, but as t becomes thicker, the magnetic flux density improves and the magnetic field distribution becomes smaller. It can be seen that the uniformity is also improved, and in particular, when t is 15 days, the magnetic flux density becomes the highest, and the variation in the magnetic field distribution can be substantially eliminated. Although not shown in FIG. 3, when t exceeds 15 times, magnetic saturation occurs, there is no improvement in magnetic flux density, and it is not possible to obtain a uniform magnetic field distribution.
以上の通り、本発明は、円筒状永久磁石の内周に設けた
主ポールピースの厚さを適切なものとし、これにより作
用空間での軸と直交する方向の磁界分布を均一にするの
で、他の方向の磁界分布も適当な補正手段を設けること
により容易に均一化することができる。As described above, the present invention makes the thickness of the main pole piece provided on the inner periphery of the cylindrical permanent magnet appropriate, thereby making the magnetic field distribution uniform in the direction orthogonal to the axis in the working space. The magnetic field distribution in other directions can also be easily made uniform by providing appropriate correction means.
第１図は本発明の一実施例に係る磁界発生装置の断面図
、第２図は作用空間の磁束密度分布を示す図である。
２：永久磁石、３：空間、３ａ：作用空間、４：ヨーク
、５：主ポールピース。FIG. 1 is a sectional view of a magnetic field generator according to an embodiment of the present invention, and FIG. 2 is a diagram showing the magnetic flux density distribution in the working space. 2: Permanent magnet, 3: Space, 3a: Working space, 4: Yoke, 5: Main pole piece.
Claims (1)
磁化された一対の円筒状永久磁石と、前記永久磁石の内
側に設置された、前記永久磁石の磁束を前記空間の所定
区域に集束させる略円板状の一対の主ポールピースと、
前記永久磁石同志を磁気的に結合させるヨークとを有す
る磁界発生装置において、前記主ポールピースは中央部
と外周部とが中間部よりも厚肉に形成されており、かつ
、該中間部の厚さは前記所定区域における軸と直角方向
の磁界分布が実質的に均一であるような厚さを有するこ
とを特徴とする磁界発生装置。(1) A pair of radially magnetized cylindrical permanent magnets facing each other on the same axis with a space in between, and a pair of cylindrical permanent magnets installed inside the permanent magnets, directing the magnetic flux of the permanent magnets to a predetermined area of the space. A pair of approximately disc-shaped main pole pieces to be focused;
In the magnetic field generating device including the yoke that magnetically couples the permanent magnets, the main pole piece has a central portion and an outer peripheral portion thicker than the intermediate portion, and A magnetic field generating device, wherein the thickness is such that the magnetic field distribution in the direction perpendicular to the axis in the predetermined area is substantially uniform.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62101291A JPS63266804A (en) | 1987-04-24 | 1987-04-24 | Magnetic field generator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62101291A JPS63266804A (en) | 1987-04-24 | 1987-04-24 | Magnetic field generator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63266804A true JPS63266804A (en) | 1988-11-02 |
Family
ID=14296741
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62101291A Pending JPS63266804A (en) | 1987-04-24 | 1987-04-24 | Magnetic field generator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63266804A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2812901A4 (en) * | 2012-02-10 | 2015-06-24 | Nanalysis Corp | Pole piece |
| JP2022000241A (en) * | 2014-09-05 | 2022-01-04 | ハイパーファイン，インコーポレイテッド | Low magnetic field magnetic resonance imaging method and device |
-
1987
- 1987-04-24 JP JP62101291A patent/JPS63266804A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2812901A4 (en) * | 2012-02-10 | 2015-06-24 | Nanalysis Corp | Pole piece |
| US9341690B2 (en) | 2012-02-10 | 2016-05-17 | Nanalysis Corp. | Pole piece |
| JP2022000241A (en) * | 2014-09-05 | 2022-01-04 | ハイパーファイン，インコーポレイテッド | Low magnetic field magnetic resonance imaging method and device |
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