JP4725702B2

JP4725702B2 - Magnetic field detecting element and magnetic field measuring apparatus using the same

Info

Publication number: JP4725702B2
Application number: JP2004133261A
Authority: JP
Inventors: 茂樹星野; 瑞樹岩波; 昌弘土屋; 眞人岸
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2004-04-28
Filing date: 2004-04-28
Publication date: 2011-07-13
Anticipated expiration: 2024-04-28
Also published as: JP2005315697A

Description

本発明は、磁界検出素子及びそれらを用いた磁界測定装置に関し、特に部品実装されたプリント基板やMCM（マルチチップモジュール）に搭載されているLSIパッケージの外部ピンやLSIチップ上の配線から放射される近傍磁界を検出するために用いられる磁界検出素子及びそれを用いた磁界測定装置に関する。 The present invention relates to a magnetic field detection element and a magnetic field measurement apparatus using the same, and in particular, is emitted from an external pin of an LSI package mounted on a printed circuit board on which a component is mounted or an MCM (multichip module) and wiring on the LSI chip. The present invention relates to a magnetic field detection element used for detecting a nearby magnetic field and a magnetic field measurement apparatus using the same.

従来、ＥＭＩ（Electric Magnetic Interference：電磁波障害）の対策に関連した技術において、部品実装されたプリント基板やMCMなどから放射される近傍磁界の検出が重要視されつつあるが、通常、基板、MCMやLSIから放射される電磁界の発生源の特定を電界や磁界センサを用いて測定している。現在、それらの測定のうち、磁界測定としては一般的にループコイルセンサが用いられ、ル―プコイルセンサは10cmから1mm以下のループ検出面積のものが使用されている。 Conventionally, in the technology related to measures against EMI (Electric Magnetic Interference), detection of a near magnetic field radiated from a printed circuit board on which a component is mounted, MCM, or the like has been regarded as important. The source of the electromagnetic field radiated from LSI is measured using an electric field or magnetic field sensor. Currently, among these measurements, a loop coil sensor is generally used as the magnetic field measurement, and a loop coil sensor having a loop detection area of 10 cm to 1 mm or less is used.

ループコイル型センサにおいては、プリント基板の材料で構成されたものやセラミックスで製作されたものが市販されており、ある方向限定では有るが100μm以下の分解能を持つ薄膜型ループ型センサの報告もなされている。 As loop coil sensors, printed circuit board materials and ceramics are commercially available, and thin-film loop sensors with a resolution of 100 μm or less have been reported, although limited in a certain direction. ing.

また、最近、基板上の配線等に対しての磁気光学効果を有する結晶（MO結晶）と光ファイバを利用した磁界検出素子についても研究が行なわれている。 Recently, research has also been conducted on a magnetic field detection element using a crystal (MO crystal) having a magneto-optic effect on wiring on a substrate and the like and an optical fiber.

このようなＭＯ結晶と光ファイバを利用した磁界検出素子の一例を図１１に示す。中心にコア領域１２、この周囲にクラッド領域１３を形成している光ファイバ１１の先端部がＭＯ結晶１４の上面に垂直に接着され、ＭＯ結晶１４の底面には誘電体のミラー薄膜１５が形成されている。基板上の配線からの磁界を測定する場合は、磁界検出素子の先端のＭＯ結晶１４を測定対象である配線に対向させた状態で、光ファイバ１１を通してレーザ光をＭＯ結晶１４に入力する。ＭＯ結晶１４の底面のミラー薄膜１５で反射してきた光の偏光角の変化を検出することで、配線上の磁界を測定することができる。 An example of a magnetic field detection element using such an MO crystal and an optical fiber is shown in FIG. The tip of the optical fiber 11 forming the core region 12 at the center and the cladding region 13 around the core region is bonded perpendicularly to the upper surface of the MO crystal 14, and a dielectric mirror thin film 15 is formed on the bottom surface of the MO crystal 14. Has been. When measuring the magnetic field from the wiring on the substrate, laser light is input to the MO crystal 14 through the optical fiber 11 with the MO crystal 14 at the tip of the magnetic field detection element facing the wiring to be measured. By detecting a change in the polarization angle of the light reflected by the mirror thin film 15 on the bottom surface of the MO crystal 14, the magnetic field on the wiring can be measured.

磁界計測において、一般的な配線上の磁界分布を測定する際には、ループコイル型センサでは横方向の磁界を検出できるが、空間分解能はそれほど高くできない。その上、センサの構造上、金属成分を除くことができないため、配線への影響も避けられず、電界成分からの影響も常に考えなければならない。このような影響の問題は、空間分解能を向上するために測定物に極めて接近させる必要があることから、高分解能化に伴って増大するものと考えられている。 In magnetic field measurement, when measuring a magnetic field distribution on a general wiring, a loop coil type sensor can detect a horizontal magnetic field, but the spatial resolution cannot be so high. In addition, since the metal component cannot be removed due to the structure of the sensor, the influence on the wiring cannot be avoided, and the influence from the electric field component must always be considered. The problem of such an effect is considered to increase as the resolution is increased because it is necessary to make the measured object very close to improve the spatial resolution.

一方、図１１に示したような従来の、磁気光学結晶を光ファイバの先端に接着した磁界検出素子では、電界の影響はほとんどなく、配線への影響も少なく、高空間分解能化は比較的容易であるが、検出磁界成分は光の方向に規定され、基板に対して高さ方向の磁界成分を検出することになる。 On the other hand, the conventional magnetic field detection element in which the magneto-optic crystal is bonded to the tip of the optical fiber as shown in FIG. 11 has little influence on the electric field, little influence on the wiring, and high spatial resolution is relatively easy. However, the detected magnetic field component is defined in the light direction, and the magnetic field component in the height direction with respect to the substrate is detected.

ＭＯ結晶を光ファイバ先端に設けたもので、横方向磁界を検出できる磁界検出素子に関しては、特許文献１および２に提案されたものがある。 Patent Documents 1 and 2 have proposed magnetic field detection elements in which an MO crystal is provided at the tip of an optical fiber and can detect a lateral magnetic field.

まず、特許文献１の磁界検出素子について図１２を参照して説明する。図１２は特許文献１の磁界検出素子の基本構成を示す概念図である。この図によると、発光ダイオード１０１の光が入射側光ファイバ１０２から出た後、入射側レンズ１０３、入射側全反射三角プリズム１０４、入射側偏光子１０５を通過後、直線偏光となる。偏光した光が磁気光学素子１０６を通過する際に被測定磁界の大きさに応じて偏光面は回転する。これにより、磁界の大きさに対応した強度の光が出射側偏光子１０７から得られる。この光は出射側全反射三角プリズム１０８で屈折して出射側レンズ１０９で出射側光ファイバ１１０に集光された後、光検出器１１１に導かれ光電変換され、電気信号として検出される。なお、入射側全反射三角プリズム１０４、入射側偏光子１０５、磁気光学素子１０６、出射側偏光子１０７および出射側全反射三角プリズム１０８はホルダ１１２の平面部に図１２に示す配置で固定されている。 First, the magnetic field detection element of Patent Document 1 will be described with reference to FIG. FIG. 12 is a conceptual diagram showing a basic configuration of the magnetic field detection element of Patent Document 1. According to this figure, after the light of the light emitting diode 101 exits from the incident side optical fiber 102, it passes through the incident side lens 103, the incident side total reflection triangular prism 104, and the incident side polarizer 105, and then becomes linearly polarized light. When the polarized light passes through the magneto-optical element 106, the plane of polarization rotates according to the magnitude of the magnetic field to be measured. As a result, light having an intensity corresponding to the magnitude of the magnetic field is obtained from the exit-side polarizer 107. This light is refracted by the outgoing-side total reflection triangular prism 108 and condensed on the outgoing-side optical fiber 110 by the outgoing-side lens 109, and then guided to the photodetector 111, subjected to photoelectric conversion, and detected as an electrical signal. The incident-side total reflection triangular prism 104, the incident-side polarizer 105, the magneto-optical element 106, the output-side polarizer 107, and the output-side total reflection triangular prism 108 are fixed to the flat portion of the holder 112 in the arrangement shown in FIG. Yes.

次に、特許文献２の磁界検出素子について図１３を参照して説明する。図１３の（ａ）に特許文献２の光磁気素子の基本構成を示す斜視図で、同図（ｂ）はこの素子の先端部の分解図である。図１３によると、入力用の光ファイバ２０１によって導かれた光は、ガラス製ガイド２０２の傾斜した端面２０３で反射し、薄型の偏光子２０４により直線偏波され、磁気光学結晶２０５に入射される。このとき、光路に対して平行な方向の磁界の強さに伴い偏光面が回転する。磁気光学結晶２０５を透過した光は誘電体反射鏡２０６により全反射され、再び磁気光学結晶２０５により偏光面が回転し、薄型の偏光子２０４と透過方向が互いに４５°の角度にある薄型の偏光子２０８を通過して、出力用のファイバ２０９に導かれる。なお、誘電体反射鏡２０６は、薄型の偏光子２０４から磁気光学結晶２０５に入射した光を全反射して、薄型の偏光子２０８に入射させるように、磁気光学結晶２０５との間にスペーサ２０７を介在して配設されている（図１３（ｂ））。
特開平08-105918号公報特開平05-203680号公報 Next, the magnetic field detection element of Patent Document 2 will be described with reference to FIG. FIG. 13A is a perspective view showing the basic configuration of the magneto-optical element of Patent Document 2, and FIG. 13B is an exploded view of the tip of this element. According to FIG. 13, the light guided by the input optical fiber 201 is reflected by the inclined end surface 203 of the glass guide 202, linearly polarized by the thin polarizer 204, and incident on the magneto-optic crystal 205. . At this time, the plane of polarization rotates with the strength of the magnetic field in the direction parallel to the optical path. The light transmitted through the magneto-optic crystal 205 is totally reflected by the dielectric reflector 206, the polarization plane is rotated again by the magneto-optic crystal 205, and the thin polarizer 204 and the thin polarized light whose transmission directions are at an angle of 45 ° to each other. The light passes through the child 208 and is guided to the output fiber 209. The dielectric reflecting mirror 206 totally reflects the light incident on the magneto-optic crystal 205 from the thin polarizer 204 and enters the magneto-optic crystal 205 so as to enter the spacer 207. (FIG. 13B).
Japanese Unexamined Patent Publication No. 08-105918 Japanese Patent Laid-Open No. 05-203680

しかしながら、上記の特許文献１の構成ではプリズムが必ず2つ必要であり、磁界検出素子の先端部を小さくすることが困難であり、微小な領域の測定や高分解能な計測には向いていない。 However, in the configuration of the above-mentioned Patent Document 1, two prisms are necessarily required, and it is difficult to reduce the tip of the magnetic field detection element, which is not suitable for measurement of a minute region or high-resolution measurement.

また、上記の特許文献２の構成では、磁気光学結晶と誘電体反射鏡との間にスペーサを介在させて入力側の光と出力側の光を別々の偏光子に通す必要があり、その結果、製作過程で調整が難しくなるという問題が生じる。また、特許文献１の磁界検出素子と同様で、磁界検出素子の先端部分を構成する部品が多いため、微小な領域の測定や高分解能な計測には向いていない。 Further, in the configuration of the above-mentioned Patent Document 2, it is necessary to pass the light on the input side and the light on the output side through different polarizers by interposing a spacer between the magneto-optic crystal and the dielectric reflector, and as a result, The problem that adjustment becomes difficult during the production process arises. Further, similar to the magnetic field detection element of Patent Document 1, since there are many parts constituting the tip portion of the magnetic field detection element, it is not suitable for measurement of a minute region or measurement with high resolution.

以上のように、高空間分解能（例えば１００μｍ以下の空間分解能）の計測であって、配線に影響が少なくかつ電界の影響を受けない、横方向磁界の検出については難しい状況であった。 As described above, it has been difficult to detect a lateral magnetic field that is a measurement with a high spatial resolution (for example, a spatial resolution of 100 μm or less) and has little influence on the wiring and is not affected by the electric field.

本発明の目的は、超小型で配線に影響が少なくかつ電界の影響を受けずに高分解能な横方向の磁界成分の計測が可能な磁界検出素子及び高分解能な磁界計測装置を提供することにある。 An object of the present invention is to provide a magnetic field detecting element and a high-resolution magnetic field measuring apparatus that are ultra-compact, have little influence on wiring, and can measure a high-resolution lateral magnetic field component without being affected by an electric field. is there.

上記目的を達成するために、本発明は、三角プリズムの直角部を挟む一方の面に光ファイバの先端面を接着し、他方の面に磁気光学結晶を接着し、該三角プリズムの直角部に対向する面に誘電体ミラーを形成した磁界検出素子であって、該三角プリズムに、該光ファイバのコア径と略同径のコア部をレーザ加工によって形成し、該コア部に合うように該光ファイバのコア部を接合した磁界検出素子を提供する。あるいは、光ファイバの先端を45°に斜め光学研磨し、光がその面で反射される方向の光ファイバの側面を面だし加工して、その面に磁気光学結晶を貼り付けた磁界検出素子を提供する。 In order to achieve the above object, according to the present invention, the tip surface of the optical fiber is bonded to one surface sandwiching the right angle portion of the triangular prism, the magneto-optic crystal is bonded to the other surface, and the right angle portion of the triangular prism is bonded. A magnetic field detecting element in which a dielectric mirror is formed on an opposing surface, wherein a core portion having a diameter substantially equal to the core diameter of the optical fiber is formed on the triangular prism by laser processing, and the core portion is fitted to the core portion. Provided is a magnetic field detection element in which core portions of optical fibers are joined . Alternatively, a magnetic field detection element in which the tip of the optical fiber is optically polished at an angle of 45 °, the side surface of the optical fiber in the direction in which the light is reflected on the surface is processed, and a magneto-optic crystal is attached to the surface. provide.

このように本発明では、微小な三角プリズムの直角部を挟む２面の一方に光ファイバ先端が接着され、そのプリズムの他の面に磁気光学結晶が接着された構造や、光ファイバの先端を斜め光学研磨加工し、その光ファイバの側面を光学研磨し、その研磨部分に磁気光学結晶が接着された構造にすることにより、磁気光学結晶内を伝播する方向を測定対象物に対して横方向にすることができ、その方向の磁界を計測できることになる。光ファイバの光ビーム径と磁気光学結晶の厚さ及び磁気光学結晶内における光透過位置と測定物までの間隔によって分解能が決まり、本発明の構造を有する素子ではより測定物に接近させることが可能になるので、高分解能に横方向の磁界成分を計測することが可能になる。かつ、微小プリズム、磁気光学結晶と光ファイバで構成される本磁界検出素子では、3次元の分布測定が容易に可能になり、かつその先端サイズが小さいので、そのサイズより大きな隙間に挿入して、内部の磁界の検出が可能になるものである。さらに、磁気検出部には金属材料を用いず、かつ電界による検出もないことから、配線に影響が少なくかつ電界の影響を受けない、高分解能に横方向の磁界成分を計測できる素子を製造でき、それらの素子を用いて微小領域での高分解能な横方向磁界成分計測が可能になる。 As described above, in the present invention, the structure in which the tip of the optical fiber is bonded to one of the two surfaces sandwiching the right angle portion of the minute triangular prism and the magneto-optic crystal is bonded to the other surface of the prism, or the tip of the optical fiber is attached. By obliquely polishing optically, optically polishing the side surface of the optical fiber, and forming a structure in which the magneto-optical crystal is bonded to the polished portion, the direction of propagation in the magneto-optical crystal is transverse to the measurement object. The magnetic field in that direction can be measured. The resolution is determined by the light beam diameter of the optical fiber, the thickness of the magneto-optic crystal, the light transmission position in the magneto-optic crystal and the distance to the measurement object, and the element having the structure of the present invention can be closer to the measurement object. Therefore, it is possible to measure the horizontal magnetic field component with high resolution. In addition, this magnetic field detection element composed of a micro prism, magneto-optic crystal and optical fiber makes it easy to measure three-dimensional distribution, and its tip size is small, so it can be inserted into a gap larger than that size. The internal magnetic field can be detected. Furthermore, since no magnetic material is used for the magnetic detection unit and no detection is performed by an electric field, it is possible to manufacture an element capable of measuring a horizontal magnetic field component with high resolution that has little influence on wiring and is not affected by an electric field. By using these elements, it is possible to measure a horizontal magnetic field component with high resolution in a minute region.

本発明によれば、光ファイバの先端に光を直角に曲げることができる微小プリズムを設置してそのプリズムの側面に磁気光学結晶を配置した構造や、光ファイバの先端を斜め加工して光を垂直に曲げられるようにし、光の曲がる方向の光ファイバ側面を加工して磁気光学結晶を接着した構造の磁界検出素子を用いることによって、測定物に極めて素子を接近させることができると共に、測定物にほとんど影響することなく、高空間分解能で、横方向の磁界を検出できる。 According to the present invention, a structure in which a micro prism capable of bending light at a right angle is installed at the tip of an optical fiber and a magneto-optic crystal is arranged on the side surface of the prism, or the tip of the optical fiber is obliquely processed to transmit light. By using a magnetic field detecting element having a structure in which the optical fiber side surface in the direction in which the light bends is bent and the magneto-optical crystal is bonded, the element can be brought very close to the object to be measured. The horizontal magnetic field can be detected with a high spatial resolution.

次に、本発明の実施の形態について、図１〜図６を参照して、詳細に説明する。 Next, embodiments of the present invention will be described in detail with reference to FIGS.

図１〜図５は本発明の実施の形態を示すもので、光ファイバの先端加工や微小プリズムを配置した部分に磁気光学効果を有する結晶を取付けた構造を持つ磁界検出素子の先端部の構成図を示したものである。 1 to 5 show an embodiment of the present invention, and the configuration of the tip of a magnetic field detection element having a structure in which a crystal having a magneto-optic effect is attached to a portion where the tip of an optical fiber is processed or a micro prism is arranged. FIG.

本発明の第１の実施形態について述べる。 A first embodiment of the present invention will be described.

図１は第１の実施形態の横方向磁界検出素子を示す構成図である。 FIG. 1 is a configuration diagram showing the transverse magnetic field detection element of the first embodiment.

図１の形態においては、シングルモードファイバまたはシングルモードファイバ先端部分のコア領域を拡大したファイバである光ファイバ２１の先端に微小な三角プリズム（以下、微小プリズム２６と称する）が透明接着剤によって接着されている。光ファイバ２１は微少プリズム２６の直角部を挟む２面のうちの一方の面に接着され、もう一方の面にＭＯ結晶（ＭＯ薄膜）２４が接着剤によって接着されている。ＭＯ結晶２４の微小プリズム２６に対して反対の面には誘電体のミラー薄膜２５が形成されている。さらに、微小プリズム２６の直角部と対向する面（４５°の斜面）にも誘電体のミラー薄膜２７が形成されている。 In the form of FIG. 1, a small triangular prism (hereinafter referred to as a small prism 26) is bonded to the tip of an optical fiber 21 which is a single mode fiber or a fiber in which the core region of the single mode fiber tip is enlarged by a transparent adhesive. Has been. The optical fiber 21 is bonded to one of two surfaces sandwiching the right angle portion of the micro prism 26, and an MO crystal (MO thin film) 24 is bonded to the other surface with an adhesive. A dielectric mirror thin film 25 is formed on the surface of the MO crystal 24 opposite to the microprism 26. Further, a dielectric mirror thin film 27 is also formed on the surface (45 ° slope) facing the right angle portion of the microprism 26.

この構成では、光ファイバ２１のコア領域２２を伝播してきたレーザー光の光路が、一旦微小プリズム２６のミラー薄膜２７によって直角に曲げられ、光ファイバ２１の光路に対して直角な光がMO結晶２４に入射するようにしている。したがって、基板上の配線などの被測定物にファイバ先端の微小プリズムの接近させたとき、ＭＯ結晶を透過する光の方向が基板上の配線などの被測定物に対して水平な方向（横方向）を向くので、横磁界の検出が可能である。 In this configuration, the optical path of the laser light propagating through the core region 22 of the optical fiber 21 is once bent at a right angle by the mirror thin film 27 of the microprism 26, and the light perpendicular to the optical path of the optical fiber 21 is MO crystal 24. It is made to enter. Therefore, when the micro prism at the tip of the fiber is brought close to the object to be measured such as the wiring on the substrate, the direction of the light passing through the MO crystal is horizontal (lateral direction) with respect to the object to be measured such as the wiring on the substrate. ), It is possible to detect a transverse magnetic field.

なお、微小プリズム２６は被測定物への影響を考え、磁気光学効果を持たず、かつ金属成分が含まれない材料を使用する。 The microprism 26 is made of a material that does not have a magneto-optical effect and does not contain a metal component in consideration of the influence on the object to be measured.

次に、本発明の第２の実施形態について述べる。 Next, a second embodiment of the present invention will be described.

図２は第２の実施形態の横方向磁界検出素子を示す構成図である。ここでは第１の実施形態と同じ部分には同一符号を付してその説明を割愛する。 FIG. 2 is a configuration diagram showing the transverse magnetic field detection element of the second embodiment. Here, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

第２の実施形態では、図１の微小プリズム２６に代えて、図２に示すように、あらかじめ光導波路領域（コア領域）３７が形成された微小プリズム３６が用いられている。微小プリズム３６の光導波路領域３７は光ファイバ２１のコア領域２２と結合させてある。 In the second embodiment, instead of the micro prism 26 of FIG. 1, a micro prism 36 in which an optical waveguide region (core region) 37 is formed in advance is used as shown in FIG. The optical waveguide region 37 of the microprism 36 is coupled to the core region 22 of the optical fiber 21.

次に、本発明の第３の実施形態について述べる。 Next, a third embodiment of the present invention will be described.

図３は第３の実施形態の横方向磁界検出素子を示す構成図である。ここでは第１の実施形態と同じ部分には同一符号を付してその説明を割愛する。 FIG. 3 is a block diagram showing the transverse magnetic field detection element of the third embodiment. Here, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

第３の実施形態では、図１の微小プリズム２６に代えて、図３に示すように、被測定物に接近させる先端部分４６ａが研磨加工されている微小プリズム４６が用いられている。特に、横方向の光路が微小プリズム４６の最下点にできる限り近づくように、先端部分４６ａが光の伝播に支障がない程度に研磨されている。 In the third embodiment, instead of the microprism 26 of FIG. 1, as shown in FIG. 3, a microprism 46 in which a tip end portion 46a that approaches the object to be measured is polished is used. In particular, the tip portion 46a is polished to the extent that there is no hindrance to light propagation so that the lateral optical path is as close as possible to the lowest point of the microprism 46.

次に、本発明の第４の実施形態について述べる。 Next, a fourth embodiment of the present invention will be described.

図４は第４の実施形態の横方向磁界検出素子を示す構成図である。ここでは第１の実施形態と同じ部分には同一符号を付してその説明を割愛する。 FIG. 4 is a configuration diagram showing a transverse magnetic field detection element of the fourth embodiment. Here, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

第４の実施形態では、図１の微小プリズム２６に代えて、図４に示すように、あらかじめ光導波路領域（コア領域）５７が形成された微小プリズム５６が用いられており、微小プリズム５６の被測定物に接近させる先端部分５６ａが研磨加工されている。特に、横方向の光路が微小プリズム５６の最下点にできる限り近づくように、先端部分５６ａが光の伝播に支障がない程度に研磨されている。 In the fourth embodiment, instead of the microprism 26 of FIG. 1, a microprism 56 in which an optical waveguide region (core region) 57 is formed in advance is used as shown in FIG. A tip end portion 56a that approaches the object to be measured is polished. In particular, the tip portion 56a is polished to the extent that there is no hindrance to light propagation so that the lateral optical path is as close as possible to the lowest point of the microprism 56.

次に、本発明の第５の実施形態について述べる。 Next, a fifth embodiment of the present invention will be described.

図５は第５の実施形態の横方向磁界検出素子を示す構成図である。ここでは第１の実施形態と同じ部分には同一符号を付してその説明を割愛する。 FIG. 5 is a block diagram showing the transverse magnetic field detection element of the fifth embodiment. Here, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

第５の実施形態では、図５に示すように、光ファイバ５１の先端が斜め４５°に平坦に研磨され、この研磨された斜面５１ａに誘電体のミラー薄膜２７が形成されている。さらに、研磨された斜面５１ａのミラー薄膜２７で光が直角に曲げられる方向の光ファイバ５１の側面５１ｂが平坦に研磨され、その研磨された側面５１ｂにＭＯ結晶２４が透明接着剤で接着されている。ＭＯ結晶２４の光ファイバ側面５１ｂに対して反対の面には誘電体のミラー薄膜２５が形成されている。 In the fifth embodiment, as shown in FIG. 5, the tip of the optical fiber 51 is polished flat at an oblique angle of 45 °, and a dielectric mirror thin film 27 is formed on the polished inclined surface 51a. Further, the side surface 51b of the optical fiber 51 in the direction in which the light is bent at a right angle is polished by the mirror thin film 27 on the polished slope 51a, and the MO crystal 24 is bonded to the polished side surface 51b with a transparent adhesive. Yes. A dielectric mirror thin film 25 is formed on the surface of the MO crystal 24 opposite to the optical fiber side surface 51b.

次に、第１〜第５の実施形態の磁界検出素子を使用した磁界計測装置について説明する。図６は本発明に係る磁界計測装置の一例を示すブロック図である。なお、図において光ファイバ６４は白抜き矢印で示してある。 Next, a magnetic field measurement apparatus using the magnetic field detection elements of the first to fifth embodiments will be described. FIG. 6 is a block diagram showing an example of a magnetic field measuring apparatus according to the present invention. In the figure, the optical fiber 64 is indicated by a white arrow.

図６に示すように、上述した形態の磁界検出素子６０の先端（ＭＯ結晶側）にＸＹＺステージ７１で測定対象物７１近傍が近接配置された後、横方向に移動させられる。この状態でレーザー光源６１からの光が光ファイバ６４を通ってFＡ（ファイバアンプ）６２で増幅され、偏波コントローラ６３で偏光状態が調整され、光サーキュレータ６５を通して、磁界検出素子６０に入力される。 As shown in FIG. 6, the vicinity of the measurement object 71 is placed close to the tip (MO crystal side) of the magnetic field detection element 60 having the above-described form by the XYZ stage 71 and then moved in the lateral direction. In this state, the light from the laser light source 61 passes through the optical fiber 64 and is amplified by the FA (fiber amplifier) 62, the polarization state is adjusted by the polarization controller 63, and is input to the magnetic field detection element 60 through the optical circulator 65. .

磁界検出素子６０に入力された光はＭＯ結晶に付けたミラー薄膜で反射され、光サーキュレータ６５に戻る。磁界検出素子６０から反射されてきた光は、光サーキュレータ６５でレーザー光源６１とは異なるパスにある検光子６６に入力される。検光子６６で偏光角の変化が検出され、検光子６６を経た光の強度がＦＡ６７で増幅され、光検出器（ＰＤ）６８に入力される。そして光検出器（ＰＤ）６８で光強度が電気信号に変換され、スペクトルアナライザ６９でその信号の周波数成分が検出される。つまり、所定の偏光状態に調整された光を磁界検出素子６０のＭＯ結晶内に横方向に入力しているとき、磁界検出素子６０のＭＯ結晶が磁界中にあると、その磁界強度に応じて偏光角が変化するため、この偏光角の変化を電気信号に変換することで、測定対象物７１の横方向の磁界成分を計測することができる。 The light input to the magnetic field detection element 60 is reflected by the mirror thin film attached to the MO crystal and returns to the optical circulator 65. The light reflected from the magnetic field detection element 60 is input to the analyzer 66 in a path different from the laser light source 61 by the optical circulator 65. The change in the polarization angle is detected by the analyzer 66, and the intensity of the light passing through the analyzer 66 is amplified by the FA 67 and input to the photodetector (PD) 68. A light detector (PD) 68 converts the light intensity into an electric signal, and a spectrum analyzer 69 detects the frequency component of the signal. That is, when light adjusted to a predetermined polarization state is inputted in the horizontal direction into the MO crystal of the magnetic field detection element 60, if the MO crystal of the magnetic field detection element 60 is in the magnetic field, the light is adjusted according to the magnetic field strength. Since the polarization angle changes, the magnetic field component in the lateral direction of the measurement object 71 can be measured by converting the change in the polarization angle into an electric signal.

次に、上述した各実施形態の構成について具体的な数値を挙げて、さらに詳しく説明する。 Next, the configuration of each embodiment described above will be described in more detail with specific numerical values.

（実施例１）
磁気光学（MＯ）を利用した横方向磁界を検出できる磁界検出素子として、図１に示すような外観の素子を製造した。 Example 1
An element having an appearance as shown in FIG. 1 was manufactured as a magnetic field detection element capable of detecting a lateral magnetic field using magneto-optic (MO).

ＭＯ結晶２４としてはＢｉ置換型ＹＩＧ（イットリウム鉄ガーネット）薄膜結晶を研磨加工し、磁化方向が面に対して平行方向になるようにしたものを使用した。一方、光を垂直に曲げるために使用する微小プリズム２６として、BK−７の材料を使用し、断面が直角二等辺三角形で、直角を挟む２辺が少なくとも０．３ｍｍ以下であるプリズムを使用した。そのプリズムの直角部に対向した面には、使用する波長の光を９０％以上反射できる誘電体多層膜のミラー薄膜２７を形成した。 As the MO crystal 24, a Bi-substituted YIG (yttrium iron garnet) thin film crystal was polished so that the magnetization direction was parallel to the surface. On the other hand, a BK-7 material was used as the microprism 26 used for bending light vertically, and a prism having a right-angled isosceles triangle and at least 0.3 mm between two sides sandwiching the right angle was used. . A mirror thin film 27 of a dielectric multilayer film capable of reflecting 90% or more of light having a wavelength to be used was formed on the surface of the prism facing the right angle portion.

以上のような微小プリズム２６の直角部を挟む２面の一方にコア径１０μｍのシングルモードの光ファイバ２１の先端面を透明接着剤で接着し、他方の面に前述のように研磨加工された約１００μｍの厚さのＭＯ結晶２４を透明接着剤を用いて接着した。ＭＯ結晶２４にはあらかじめ接着面の反対側に反射率９０％以上の誘電体多層膜のミラー薄膜２５を形成した。 The tip surface of a single mode optical fiber 21 having a core diameter of 10 μm was bonded to one of the two surfaces sandwiching the right angle portion of the microprism 26 as described above with a transparent adhesive, and the other surface was polished as described above. The MO crystal 24 having a thickness of about 100 μm was bonded using a transparent adhesive. On the MO crystal 24, a mirror thin film 25 of a dielectric multilayer film having a reflectivity of 90% or more was previously formed on the opposite side of the adhesion surface.

微小プリズム２６に光ファイバ２１を接着する際には、光ファイバ２１のコア領域２２がＭＯ結晶２４を接着した直角の面から約５０μｍの位置にくるようにした。 When the optical fiber 21 was bonded to the microprism 26, the core region 22 of the optical fiber 21 was positioned at a position of about 50 μm from the perpendicular surface to which the MO crystal 24 was bonded.

以上のようにして作製した磁界検出素子を図６に示される磁界計測システムに組み込み、１．５５μｍの波長で１ｍＷの出力の半導体レーザーの光源６１からの光を光ファイバ６４を通して、ＥＤＦＡ（エルビウム添加ファイバアンプ）で１０ｍＷに増幅し、偏波コントローラ６３で偏光状態を調節して、光サーキュレータ６５を通して前述のような構成の磁界検出素子６０に入力する。ＭＯ結晶のミラー面で反射してきた光を光サーキュレータ６５を通して、レーザー光源６１とは異なるパスにある検光子６６で偏光角の変化を検出し、磁界強度変化を光強度の変化に変換し、高速光検出器（ＰＤ）で光強度を電気信号に変換し、スペクトルアナライザ６９によって、信号の周波数成分を検出した。 The magnetic field detection element manufactured as described above is incorporated in the magnetic field measurement system shown in FIG. 6, and light from a semiconductor laser light source 61 having a wavelength of 1.55 μm and an output of 1 mW is passed through an optical fiber 64 and EDFA (erbium added). The optical signal is amplified to 10 mW by a fiber amplifier), the polarization state is adjusted by the polarization controller 63, and is input to the magnetic field detection element 60 having the above-described configuration through the optical circulator 65. The light reflected by the mirror surface of the MO crystal is passed through the optical circulator 65, the change in the polarization angle is detected by the analyzer 66 in a path different from the laser light source 61, and the change in the magnetic field intensity is converted into the change in the light intensity. The light intensity was converted into an electrical signal by a photodetector (PD), and the frequency component of the signal was detected by a spectrum analyzer 69.

以上のようにして製作した磁界検出素子と計測システムを用いて、信号電力１５ｄＢｍ、周波数１０ＭＨｚの信号を入力した２．２ｍｍの配線幅で、特性インピーダンスが５０オームのマイクロストリップ構造の配線上の磁界の計測を行なったところ、配線に対して横断する方向に磁界検出素子６０を移動させることによって横方向の磁界成分を計測することができることを確認でき、図７のようなデータを得ることができた。１ＧＨｚの周波数においても同様の磁界分布データが得られた。 Using the magnetic field detection element and the measurement system manufactured as described above, the magnetic field on the microstrip structure wiring having a characteristic impedance of 50 ohms with a wiring width of 2.2 mm to which a signal with a signal power of 15 dBm and a frequency of 10 MHz is input. As a result of the measurement, it can be confirmed that the magnetic field component in the lateral direction can be measured by moving the magnetic field detection element 60 in the direction transverse to the wiring, and data as shown in FIG. 7 can be obtained. It was. Similar magnetic field distribution data was obtained at a frequency of 1 GHz.

（実施例２）
磁気光学（ＭＯ）を利用した横方向磁界を検出できる磁界検出素子として、図２のような外観の素子を製造した。ＭＯ結晶２４としてはＢｉ置換型ＹＩＧ（イットリウム鉄ガーネット）薄膜結晶を研磨加工し、磁化方向が面に対して平行方向になるようにしたものを使用した。一方、光を垂直に曲げるために使用する微小プリズム３６として、石英を使用し、断面が直角二等辺三角形で、直角を挟む２辺が少なくとも０．３ｍｍ以下であるプリズムを使用した。そのプリズムの直角部に対向した面には使用する波長の光を９０％以上反射できる誘電体多層膜のミラー薄膜２７を形成した。 (Example 2)
An element having an appearance as shown in FIG. 2 was manufactured as a magnetic field detection element capable of detecting a transverse magnetic field using magneto-optic (MO). As the MO crystal 24, a Bi-substituted YIG (yttrium iron garnet) thin film crystal was polished so that the magnetization direction was parallel to the surface. On the other hand, as the microprism 36 used for bending light vertically, quartz was used, and a prism having a right-angled isosceles triangle and two sides sandwiching a right angle of at least 0.3 mm or less was used. A mirror thin film 27 of a dielectric multilayer film capable of reflecting 90% or more of light having a wavelength to be used was formed on the surface facing the right angle portion of the prism.

そのような石英製のプリズムにレンズで１０μｍ程度に集光された波長８０５ｎｍ、ピーク強度３００ｋＷ/ｃｍ²、幅２００ｆｓ、繰り返し２５０ｋＨｚのパルスレーザを照射して、プリズム内にシングルモードの光ファイバ２１のコア領域２２と同程度の径（８μｍ）の光導波路領域３７を形成した。導波路領域３７は微小プリズム３６の直角部から約３０μｍの位置に作製した。微小プリズム３６に作製された導波路領域３７にシングルモードの光ファイバ２１のコア領域２２が合うように光軸調整して、できるだけロスがないように微小プリズム３６の直角部を挟む２面の一方に光ファイバ２１を接着し、他方の面に前述のように研磨加工された約１００μｍの厚さのＭＯ結晶２４を透明接着剤で接着した。微小プリズム３６に光ファイバ２１を接着する際には、光ファイバ２１のコア領域２２がＭＯ結晶２４を接着した直角部の面から約３０μｍの位置に来るようにした。 Such a quartz prism is irradiated with a pulse laser having a wavelength of 805 nm, a peak intensity of 300 kW / cm ² , a width of ²⁰⁰ fs, and a repetition rate of 250 kHz, which is condensed to about 10 μm by a lens. An optical waveguide region 37 having the same diameter (8 μm) as that of the core region 22 was formed. The waveguide region 37 was produced at a position of about 30 μm from the right angle portion of the microprism 36. The optical axis is adjusted so that the core region 22 of the single-mode optical fiber 21 is aligned with the waveguide region 37 formed in the microprism 36, and one of the two surfaces sandwiching the right angle portion of the microprism 36 so that there is as little loss as possible. The optical fiber 21 was bonded to the surface, and the MO crystal 24 having a thickness of about 100 μm polished as described above was bonded to the other surface with a transparent adhesive. When the optical fiber 21 was bonded to the micro prism 36, the core region 22 of the optical fiber 21 was positioned at a position of about 30 μm from the surface of the right angle portion where the MO crystal 24 was bonded.

ＭＯ結晶２４にはあらかじめ接着面の反対側に反射率９０％以上の誘電体多層膜のミラー薄膜２５を形成した。 On the MO crystal 24, a mirror thin film 25 of a dielectric multilayer film having a reflectivity of 90% or more was previously formed on the opposite side of the adhesion surface.

以上のようにして作製した磁界検出素子を図６に示される磁界計測システムに組み込み、１．５５μｍの波長で１ｍＷの出力の半導体レーザーの光源６１からの光を光ファイバ６４を通して、EDFA（ファイバアンプ６２）で１０ｍＷに増幅し、偏波コントローラ６３で偏光状態を調節して、光サーキュレータ６５を通して前述のような構成の磁界検出素子６０に入力する。ＭＯ結晶のミラー面で反射してきた光を光サーキュレータ６５を通して、レーザー光源６１とは異なるパスにある検光子６６で偏光角の変化を検出し、磁界強度変化を光強度の変化に変換し、高速光検出器（ＰＤ）６８で光強度を電気信号に変換し、スペクトルアナライザ６９によって、信号の周波数成分を検出した。 The magnetic field detection element manufactured as described above is incorporated in the magnetic field measurement system shown in FIG. 6, and light from the light source 61 of the semiconductor laser having a wavelength of 1.55 μm and an output of 1 mW is passed through the optical fiber 64 through an EDFA (fiber amplifier). 62), the polarization state is adjusted by the polarization controller 63, and the light is input to the magnetic field detection element 60 having the above-described configuration through the optical circulator 65. The light reflected by the mirror surface of the MO crystal is passed through the optical circulator 65, the change in the polarization angle is detected by the analyzer 66 in a path different from the laser light source 61, and the change in the magnetic field intensity is converted into the change in the light intensity. A light detector (PD) 68 converted the light intensity into an electric signal, and a spectrum analyzer 69 detected the frequency component of the signal.

以上のようにして製作した磁界検出素子と計測システムを用いて、配線幅８０μｍの一本の配線が２回屈曲され、中央部で３本となるマイクロストリップ構造の配線に信号電力１５ｄＢｍ、周波数１０MHzの信号を入力し、その３本の配線上の磁界計測を行なった。配線に対して横断する方向に磁界検出素子６０を移動させることによって横方向の磁界成分を計測することができることを確認でき、図８のようなデータを得ることができた。 Using the magnetic field detection element and the measurement system manufactured as described above, one wiring having a wiring width of 80 μm is bent twice, and the wiring having a microstrip structure with three wires at the center portion has a signal power of 15 dBm and a frequency of 10 MHz. The magnetic field measurement was performed on the three wires. It was confirmed that the magnetic field component in the lateral direction could be measured by moving the magnetic field detection element 60 in the direction transverse to the wiring, and data as shown in FIG. 8 could be obtained.

（実施例３）
磁気光学（ＭＯ）を利用した横方向磁界を検出できる磁界検出素子として、図３のような外観の素子を製造した。ＭＯ結晶２４としてはＢｉ置換型ＹＩＧ（イットリウム鉄ガーネット）薄膜結晶を研磨加工し、磁化方向が面に対して平行方向になるようにしたものを使用した。一方、光を垂直に曲げるために使用する微小プリズム４６として、GGG（ガドリウムガリウムガーネット）材料を使用し、断面が直角二等辺三角形で、直角部を挟む２辺が少なくとも０．３ｍｍ以下であるプリズムを使用した。そのプリズムの直角部に対向した面には使用する波長の光を９０％以上反射できる誘電体多層膜のミラー薄膜２７を形成した。一方、そのような微小プリズム４６の一部を図３の構造になるように研磨加工した（ファイバに接着される面の反対側の先端部分４６ａ）。 (Example 3)
An element having an appearance as shown in FIG. 3 was manufactured as a magnetic field detection element capable of detecting a lateral magnetic field using magneto-optic (MO). As the MO crystal 24, a Bi-substituted YIG (yttrium iron garnet) thin film crystal was polished so that the magnetization direction was parallel to the surface. On the other hand, GGG (gadlium gallium garnet) material is used as the microprism 46 used for bending light vertically, and the cross section is a right isosceles triangle, and the two sides sandwiching the right angle portion are at least 0.3 mm or less. A prism was used. A mirror thin film 27 of a dielectric multilayer film capable of reflecting 90% or more of light having a wavelength to be used was formed on the surface facing the right angle portion of the prism. On the other hand, a part of such a small prism 46 was polished so as to have the structure of FIG. 3 (tip portion 46a on the opposite side of the surface bonded to the fiber).

以上のような微小プリズム４６の直角部を挟む２面の一方にコア径２０μｍのコア拡大ファイバ２１の先端面を透明接着剤で接着し、他方の面に前述のように研磨加工された約３０μｍの厚さのＭＯ結晶２４を透明接着剤で接着した。ＭＯ結晶２４にはあらかじめ接着面の反対側に反射率９０％以上の誘電体多層膜のミラー薄膜２５を形成した。微小プリズム４６に光ファイバ２１を接着する際には、光が研磨加工された部分（先端部分４６ａ）から漏れないで、光ファイバ２１のコア領域２２からの光ができるだけサイドに設けられたＭＯ結晶２４の最下点に近い部分を通過するように調整した。 The distal end surface of the core expansion fiber 21 having a core diameter of 20 μm is bonded to one of the two surfaces sandwiching the right angle portion of the microprism 46 as described above with a transparent adhesive, and the other surface is polished by about 30 μm as described above. The MO crystal 24 having a thickness of 2 mm was adhered with a transparent adhesive. On the MO crystal 24, a mirror thin film 25 of a dielectric multilayer film having a reflectivity of 90% or more was previously formed on the opposite side of the adhesion surface. When the optical fiber 21 is bonded to the microprism 46, the MO crystal in which light from the core region 22 of the optical fiber 21 is provided as much as possible without leaking from the polished portion (tip portion 46a). It adjusted so that the part close | similar to the lowest point of 24 may be passed.

以上のようにして作製した磁界検出素子を図６に示される磁界計測システムに組み込み、１．５５μｍの波長で１ｍＷの出力の半導体レーザーの光源６１からの光を光ファイバを通して、EDFA（ファイバアンプ６２）で１０ｍＷに増幅し、偏波コントローラ６３で偏光状態を調節して、光サーキュレータ６５を通して前述のような構成の磁界検出素子６０に入力する。ＭＯ結晶のミラー面で反射してきた光を光サーキュレータ６５を通して、レーザー光源６１とは異なるパスにある検光子６６で偏光角の変化を検出し、磁界強度変化を光強度の変化に変換し、高速光検出器（ＰＤ）６８で光強度を電気信号に変換し、スペクトルアナライザ６９によって、信号の周波数成分を検出した。 The magnetic field detection element manufactured as described above is incorporated in the magnetic field measurement system shown in FIG. 6, and light from a light source 61 of a semiconductor laser having a wavelength of 1.55 μm and an output of 1 mW is passed through an optical fiber to an EDFA (fiber amplifier 62). ) To 10 mW, the polarization state is adjusted by the polarization controller 63, and the light is input to the magnetic field detection element 60 having the above-described configuration through the optical circulator 65. The light reflected by the mirror surface of the MO crystal is passed through the optical circulator 65, the change in the polarization angle is detected by the analyzer 66 in a path different from the laser light source 61, and the change in the magnetic field intensity is converted into the change in the light intensity. A light detector (PD) 68 converted the light intensity into an electric signal, and a spectrum analyzer 69 detected the frequency component of the signal.

以上のようにして製作した磁界検出素子と計測システムを用いて、信号電力１５ｄＢｍ、周波数１０ＭＨｚの信号を入力した配線幅８０μｍのマイクロストリップ構造の配線上の磁界計測を行なった。配線に対して横断する方向に磁界検出素子６０を移動させることによって横方向の磁界成分を計測することができることを確認でき、図９のようなデータを得ることができた。 Using the magnetic field detection element and the measurement system manufactured as described above, magnetic field measurement was performed on a wiring having a microstrip structure with a wiring width of 80 μm to which a signal with a signal power of 15 dBm and a frequency of 10 MHz was input. It was confirmed that the magnetic field component in the lateral direction could be measured by moving the magnetic field detection element 60 in the direction transverse to the wiring, and data as shown in FIG. 9 could be obtained.

（実施例４）
磁気光学（ＭＯ）を利用した横方向磁界を検出できる磁界検出素子として、図４のような外観の素子を製造した。ＭＯ結晶２４としてはＢｉ置換型ＹＩＧ（イットリウム鉄ガーネット）薄膜結晶を研磨加工し、磁化方向が面に対して平行方向になるようにしたものを使用した。一方、光を垂直に曲げるために使用する微小プリズム５６として、石英を使用し、断面が直角二等辺三角形で、直角部を挟む２辺が少なくとも０．３ｍｍ以下であるプリズムを使用した。そのプリズムの直角部に対向した面には使用する波長の光を９０％以上反射できる誘電体多層膜のミラー薄膜２７を形成した。 Example 4
As a magnetic field detecting element capable of detecting a transverse magnetic field using magneto-optic (MO), an element having an appearance as shown in FIG. 4 was manufactured. As the MO crystal 24, a Bi-substituted YIG (yttrium iron garnet) thin film crystal was polished so that the magnetization direction was parallel to the surface. On the other hand, as the micro prism 56 used for bending light vertically, quartz was used, and a prism having a cross section of a right isosceles triangle and having two sides sandwiching the right angle portion at least 0.3 mm or less was used. A mirror thin film 27 of a dielectric multilayer film capable of reflecting 90% or more of light having a wavelength to be used was formed on the surface facing the right angle portion of the prism.

そのような石英製のプリズムにレンズで１０μｍ程度に集光された波長８０５ｎｍ、ピーク強度３００ｋＷ/ｃｍ²、幅２００ｆｓ、繰り返し２５０ｋＨｚのパルスレーザを照射して、プリズム内にシングルモードファイバのコア部と同程度の大きさの光導波路領域５７を形成した。このようにして光が導波路を伝播して直角に曲げられるようなプリズムを用いた。光ファイバ２１を接続する導波路領域５７は直角部から約３０μｍの位置に作製した。微小プリズム５６に作製された導波路領域５７が光ファイバ２１のコア領域２２に合うように光軸調整し、できるだけロスがないように微小プリズム５６の直角部を挟む２面の一方にシングルモードの光ファイバ２１を接着し、他方の面に前述のように研磨加工された約３０μｍの厚さのＭＯ結晶２４を透明接着剤で接着した。ＭＯ結晶２４にはあらかじめ接着面の反対側に反射率９０％以上の誘電体多層膜のミラー薄膜２５を形成した。 Such a quartz prism is irradiated with a pulse laser having a wavelength of 805 nm, a peak intensity of 300 kW / cm ² , a width of ²⁰⁰ fs, and a repetition rate of 250 kHz, which is condensed to about 10 μm by a lens. An optical waveguide region 57 having the same size was formed. In this way, a prism is used in which light propagates through the waveguide and is bent at a right angle. The waveguide region 57 for connecting the optical fiber 21 was produced at a position of about 30 μm from the right angle portion. The optical axis is adjusted so that the waveguide region 57 formed in the microprism 56 is aligned with the core region 22 of the optical fiber 21, and a single mode is formed on one of the two surfaces sandwiching the right angle portion of the microprism 56 so that there is as little loss as possible. The optical fiber 21 was bonded, and the MO crystal 24 having a thickness of about 30 μm polished as described above was bonded to the other surface with a transparent adhesive. On the MO crystal 24, a mirror thin film 25 of a dielectric multilayer film having a reflectivity of 90% or more was previously formed on the opposite side of the adhesion surface.

図４のように微小プリズム５６の下側の先端部分５６ａを研磨加工する際には、プリズムに形成された光導波路領域５７の光が小さなロスで伝播でき、かつプリズム内の光導波路領域５７が下面にできるだけ近くなるように加工した。 When polishing the lower end portion 56a of the micro prism 56 as shown in FIG. 4, the light in the optical waveguide region 57 formed in the prism can propagate with a small loss, and the optical waveguide region 57 in the prism Processed to be as close to the bottom surface as possible.

以上のようにして作製した磁界検出素子を図６に示される磁界計測システムに組み込み、１．５５μｍの波長で１ｍＷの出力の半導体レーザーの光源６１からの光を光ファイバ６４を通して、ＥＤＦＡ（ファイバアンプ６２）で１０ｍＷに増幅し、偏波コントローラ６３で偏光状態を調節して、光サーキュレータ６５を通して前述のような構成の磁界検出素子６０に入力する。ＭＯ結晶のミラー面で反射してきた光を光サーキュレータ６５を通して、レーザー光源６１とは異なるパスにある検光子６６で偏光角の変化を検出し、磁界強度変化を光強度の変化に変換し、光検出器（ＰＤ）６８で光強度を電気信号に変換し、スペクトルアナライザ６９によって、信号の周波数成分を検出した。 The magnetic field detection element manufactured as described above is incorporated in the magnetic field measurement system shown in FIG. 6, and light from a light source 61 of a semiconductor laser having a wavelength of 1.55 μm and an output of 1 mW is passed through an optical fiber 64 to an EDFA (fiber amplifier). 62), the polarization state is adjusted by the polarization controller 63, and the light is input to the magnetic field detection element 60 having the above-described configuration through the optical circulator 65. The light reflected by the mirror surface of the MO crystal is passed through the optical circulator 65, the change in the polarization angle is detected by the analyzer 66 in a path different from the laser light source 61, and the change in the magnetic field intensity is converted into the change in the light intensity. The detector (PD) 68 converted the light intensity into an electrical signal, and the spectrum analyzer 69 detected the frequency component of the signal.

以上のようにして製作した磁界検出素子と計測システムを用いて、信号電力１５ｄＢｍ、周波数１０ＭＨｚの信号を入力した配線幅８０μｍのマイクロストリップ構造の配線上の磁界計測を行なった。配線に対して横断する方向に磁界検出素子６０を移動させることによって横方向の磁界成分を計測することができることを確認でき、図１０のようなデータを得ることができた。 Using the magnetic field detection element and the measurement system manufactured as described above, magnetic field measurement was performed on a wiring having a microstrip structure with a wiring width of 80 μm to which a signal with a signal power of 15 dBm and a frequency of 10 MHz was input. It was confirmed that the magnetic field component in the lateral direction could be measured by moving the magnetic field detection element 60 in the direction transverse to the wiring, and data as shown in FIG. 10 could be obtained.

（実施例５）
磁気光学（ＭＯ）を利用した横方向磁界を検出できる磁界検出素子として、図５のような外観の素子を製造した。ＭＯ結晶２４としてはＢｉ置換型ＹＩＧ（イットリウム鉄ガーネット）薄膜結晶を研磨加工し、磁化方向が面に対して平行方向になるようにしたものを使用した。一方、シングルモードの光ファイバ５１の先端を４５°の角度になるように斜め光学研磨した。その斜め研磨された面（斜面５１ａ）には使用する波長の光に対して反射率９０％以上の誘電体多層膜のミラー薄膜２７を形成した。さらに、斜面５１ａのミラー薄膜２７で光が反射される方向の光ファイバ５１の側面を約５０〜６０μｍ光学研磨し、光ファイバ５１のクラッド領域５３に対して面だしを行なった。このように面だしされた面（側面５１ｂ）に前述のように研磨加工された約３０μｍの厚さのＭＯ結晶２４を透明接着剤で接着した。ＭＯ結晶２４にはあらかじめ接着面の反対側に反射率９０％以上の誘電体多層膜のミラー薄膜２５を形成した。 (Example 5)
An element having an appearance as shown in FIG. 5 was manufactured as a magnetic field detection element capable of detecting a transverse magnetic field using magneto-optic (MO). As the MO crystal 24, a Bi-substituted YIG (yttrium iron garnet) thin film crystal was polished so that the magnetization direction was parallel to the surface. Meanwhile, the tip of the single-mode optical fiber 51 was obliquely optically polished so as to have an angle of 45 °. A mirror thin film 27 of a dielectric multilayer film having a reflectivity of 90% or more with respect to light having a wavelength to be used was formed on the obliquely polished surface (slope 51a). Further, the side surface of the optical fiber 51 in the direction in which light is reflected by the mirror thin film 27 on the inclined surface 51 a is optically polished by about 50 to 60 μm, and the clad region 53 of the optical fiber 51 is surfaced. The MO crystal 24 having a thickness of about 30 μm polished as described above was adhered to the surface thus exposed (side surface 51b) with a transparent adhesive. On the MO crystal 24, a mirror thin film 25 of a dielectric multilayer film having a reflectivity of 90% or more was previously formed on the opposite side of the adhesion surface.

以上のようにして作製した磁界検出素子を図６に示される磁界計測システムに組み込み、１．５５μｍの波長で１ｍＷの出力の半導体レーザーの光源６１からの光を光ファイバ６４を通して、EDFA（ファイバアンプ６２）で１０ｍＷに増幅し、偏波コントローラ６３で偏光状態を調節して、光サーキュレータ６５を通して前述のような構成の磁界検出素子６０に入力する。ＭＯ結晶２４のミラー面で反射してきた光を光サーキュレータ６５を通して、レーザー光源６１とは異なるパスにある検光子６６で偏光角の変化を検出し、磁界強度変化を光強度の変化に変換し、高速光検出器（ＰＤ）６８で光強度を電気信号に変換し、スペクトルアナライザ６９によって、信号の周波数成分を検出した。 The magnetic field detection element manufactured as described above is incorporated in the magnetic field measurement system shown in FIG. 6, and light from the light source 61 of the semiconductor laser having a wavelength of 1.55 μm and an output of 1 mW is passed through the optical fiber 64 through an EDFA (fiber amplifier). 62), the polarization state is adjusted by the polarization controller 63, and the light is input to the magnetic field detection element 60 having the above-described configuration through the optical circulator 65. The light reflected by the mirror surface of the MO crystal 24 is passed through the optical circulator 65, the change in the polarization angle is detected by the analyzer 66 in a path different from the laser light source 61, and the change in the magnetic field intensity is converted into the change in the light intensity. The light intensity was converted into an electric signal by a high-speed photodetector (PD) 68, and the frequency component of the signal was detected by a spectrum analyzer 69.

以上のようにして製作した磁界検出素子と計測システムを用いて、信号電力１５ｄＢｍ、周波数１０ＭＨｚの信号を入力したマイクロストリップ構造８０μｍの配線幅の配線上の磁界計測を行なった。配線に対して横断する方向に磁界検出素子６０を移動させることによって横方向の磁界成分を計測することができることを確認でき、図１０のようなデータを得ることができた。 Using the magnetic field detection element and the measurement system manufactured as described above, a magnetic field measurement was performed on a wiring having a wiring width of 80 μm with a microstrip structure to which a signal with a signal power of 15 dBm and a frequency of 10 MHz was input. It was confirmed that the magnetic field component in the lateral direction could be measured by moving the magnetic field detection element 60 in the direction transverse to the wiring, and data as shown in FIG. 10 could be obtained.

本発明の第１の実施形態による磁界検出素子を示す構成図である。It is a block diagram which shows the magnetic field detection element by the 1st Embodiment of this invention. 本発明の第２の実施形態による磁界検出素子を示す構成図である。It is a block diagram which shows the magnetic field detection element by the 2nd Embodiment of this invention. 本発明の第３の実施形態による磁界検出素子を示す構成図である。It is a block diagram which shows the magnetic field detection element by the 3rd Embodiment of this invention. 本発明の第４の実施形態による磁界検出素子を示す構成図である。It is a block diagram which shows the magnetic field detection element by the 4th Embodiment of this invention. 本発明の第５の実施形態による磁界検出素子を示す構成図である。It is a block diagram which shows the magnetic field detection element by the 5th Embodiment of this invention. 本発明の磁界検出素子を用いた磁界測定装置の一実施形態を示す図である。It is a figure which shows one Embodiment of the magnetic field measuring apparatus using the magnetic field detection element of this invention. 本発明の実施例１で作製した素子を用いて測定したマイクロストリップ配線上の磁界成分の測定結果を示す図である。It is a figure which shows the measurement result of the magnetic field component on the microstrip wiring measured using the element produced in Example 1 of this invention. 本発明の実施例２で作製した素子を用いて測定したマイクロストリップ配線上の磁界成分の測定結果を示す図である。It is a figure which shows the measurement result of the magnetic field component on the microstrip wiring measured using the element produced in Example 2 of this invention. 本発明の実施例３で作製した素子を用いて測定したマイクロストリップ配線上の磁界成分の測定結果を示す図である。It is a figure which shows the measurement result of the magnetic field component on the microstrip wiring measured using the element produced in Example 3 of this invention. 本発明の実施例４及び実施例５で作製した素子を用いて測定したマイクロストリップ配線上の磁界成分の測定結果を示す図である。It is a figure which shows the measurement result of the magnetic field component on the microstrip wiring measured using the element produced in Example 4 and Example 5 of this invention. 従来用いられているMO結晶と光ファイバを用いた磁界検出素子の概略図である。It is the schematic of the magnetic field detection element using MO crystal and the optical fiber used conventionally. 特許文献１の磁界検出素子の概略図である。10 is a schematic diagram of a magnetic field detection element of Patent Document 1. FIG. 特許文献２の磁界検出素子の概略図である。It is the schematic of the magnetic field detection element of patent document 2. FIG.

Explanation of symbols

２１、５１光ファイバ
２２、５２コア領域
２３、５３クラッド領域
２４ＭＯ結晶（ＭＯ薄膜）
２５、２７ミラー薄膜
２６微小プリズム
３６導波路付きの微小プリズム
３７導波路領域
４６先端加工された微小プリズム
４６ａ、５６ａ先端部分
５１ａ斜面
５１ｂ側面
５６導波路付きの、先端加工された微小プリズム
６０磁界検出素子
６１レーザー光源
６２、６７ファイバアンプ
６３偏波コントローラ
６４光ファイバ
６５光サーキュレータ
６６検光子
６８光検出器
６９スペクトルアナライザ
６０データ収集＆制御装置
７１ＸＹＺステージ
７２測定対象物 21, 51 Optical fibers 22, 52 Core region 23, 53 Clad region 24 MO crystal (MO thin film)
25, 27 Mirror thin film 26 Micro prism 36 Micro prism 37 with waveguide 37 Waveguide region 46 Micro prism 46a, 56a with tip processed 51a Slope 51b Side surface 56 Micro prism 60 with waveguide with tip processed Magnetic field detection Element 61 Laser light source 62, 67 Fiber amplifier 63 Polarization controller 64 Optical fiber 65 Optical circulator 66 Analyzer 68 Photo detector 69 Spectrum analyzer 60 Data collection & control device 71 XYZ stage 72 Measurement object

Claims

A magnetic field detecting element for detecting a magnetic field component in a lateral direction with respect to a measurement object,
The end face of the optical fiber is bonded to one surface sandwiching the right angle portion of the triangular prism, and the magneto-optic crystal is bonded to the other surface, and a dielectric mirror is formed on the surface facing the right angle portion of the triangular prism. Has been
A magnetic field detecting element in which a core portion having substantially the same diameter as the core diameter of the optical fiber is formed on the triangular prism by laser processing, and the core portion of the optical fiber is joined to the core portion .

The magnetic field detection element according to claim 1 , wherein the optical fiber is a single mode fiber or a fiber obtained by enlarging the core of the tip of the single mode fiber.

The magnetic field detection element according to claim 1 , wherein the triangular prism uses a material that does not have a magneto-optical effect and does not include a metal component.

Near Kunar so on to the tip of the incident optical path is the magnetic field detection element when the light from the optical fiber is incident on the magneto-optical crystal is reflected by the dielectric mirror through the triangular prism, opposed to the right-angled portion of the triangular prism tip portion formed by the surface and the other surface which is polished, the magnetic field sensing element according to any one of claims 1 to 3.

A magnetic field detecting element for detecting a magnetic field component in a lateral direction with respect to a measurement object,
The tip of the optical fiber is polished flat at an angle of 45 °, a dielectric mirror is formed on the polished slope, and the side of the optical fiber in the direction in which light is bent at a right angle by the dielectric mirror is polished flat. A magnetic field detection element in which a magneto-optical crystal is bonded to the polished side surface.

Magneto-optical crystal, a magnetic field detecting element according to claims 1, dielectric mirror on the surface of which is not bonded is formed in any one of 5.

A magnetic field measuring device provided with a magnetic field sensing element according to any one of claims 1 to 6,
Equipped with semiconductor laser light source, fiber amplifier, polarization controller, optical circulator, analyzer, high-speed photodetector and spectrum analyzer,
Light from the laser light source is amplified by the fiber amplifier, the degree of polarization is adjusted by the polarization controller, and the light is input to a magnetic field detection element disposed in the vicinity of the measurement object through the optical circulator. The light reflected from the light source is input to the analyzer in a path different from the laser light source by the optical circulator, the change in the degree of polarization is detected by the analyzer, and the intensity of the light passing through the analyzer is increased at high speed. A magnetic field measuring apparatus for measuring a magnetic field component of the object to be measured by converting the electric signal into an electric signal by the high-speed photodetector and detecting the frequency component of the signal by the spectrum analyzer after inputting to the photodetector.