JPH08249615A - Magnetic head - Google Patents
Magnetic headInfo
- Publication number
- JPH08249615A JPH08249615A JP4833395A JP4833395A JPH08249615A JP H08249615 A JPH08249615 A JP H08249615A JP 4833395 A JP4833395 A JP 4833395A JP 4833395 A JP4833395 A JP 4833395A JP H08249615 A JPH08249615 A JP H08249615A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- magnetic field
- path
- frequency
- high frequency
- 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
Landscapes
- Recording Or Reproducing By Magnetic Means (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、超高密度磁気記録媒体
に記録された情報（微小磁界）の読み取りにも対応可能
な再生用の磁気ヘッド、あるいはメカ系の高感度な位置
センサ用の磁気ヘッド等に応用される磁気ヘッドに関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reproducing magnetic head capable of reading information (micro magnetic field) recorded on an ultra high density magnetic recording medium, or a mechanically sensitive position sensor. The present invention relates to a magnetic head applied to a magnetic head and the like.
【０００２】[0002]
【従来の技術】従来、磁気記録媒体に記録された情報を
読み取るための再生用磁気ヘッドとして、磁性体の高周
波透磁率の外部磁界依存性を利用する磁気ヘッドがあっ
た。この磁気ヘッドの動作原理は、１．検知対象の外部
磁界の周波数より高い周波数を有する高周波磁界を磁性
体に印加し、２．磁性体の高周波領域の透磁率を外部磁
界により変化させる。そして、３．磁性体に結合される
電磁素子により、磁性体の高周波領域でのインダクタン
ス変化を検知することにより外部磁界を検知するもので
ある。この磁気ヘッドの特徴は、微小な外部磁気モーメ
ントを検知する際の出力が、従来のインダクティブヘッ
ドと比較し、高いという特徴を持ち、新しい再生用磁気
ヘッド、あるいは、メカ系の位置センサ用の磁気ヘッド
等への応用が期待されている。2. Description of the Related Art Conventionally, as a reproducing magnetic head for reading information recorded on a magnetic recording medium, there has been a magnetic head utilizing the external magnetic field dependence of the high frequency magnetic permeability of a magnetic material. The operating principle of this magnetic head is as follows. 1. applying a high-frequency magnetic field having a frequency higher than the frequency of the external magnetic field to be detected to the magnetic body, The permeability of the magnetic material in the high frequency region is changed by an external magnetic field. And 3. An electromagnetic element coupled to a magnetic body detects an external magnetic field by detecting a change in inductance of the magnetic body in a high frequency region. The characteristic of this magnetic head is that the output when detecting a minute external magnetic moment is higher than that of the conventional inductive head, and it is a new magnetic head for reproduction or a magnetic sensor for mechanical position sensors. It is expected to be applied to heads and the like.
【０００３】この磁気ヘッドについては様々なものが提
案されている。図８に従来技術の一例として、特開昭５
８−６８２０５号公報記載の磁気再生装置の構成を示
す。図８の磁気再生装置では、磁性体１１０があり、こ
れに結合された第１インダクタンス素子１１１と第２の
インダクタンス素子１１２があり、磁気ヘッドを構成し
ている。第１のインダクタンス素子１１１はコンデンサ
１１４とともに一次側共振回路を構成し、高周波電源１
１７に接続される。そして、第２のインダクタンス素子
１１２はコンデンサ１１８とともに二次側同調回路を構
成し、検波回路１２０に接続される構成である。この磁
気ヘッドは磁性体１１０の高周波透磁率の変化を利用し
ている。この磁気ヘッドは高出力が得られるが、磁性体
１１０全体での磁気記録媒体１１３に起因する磁界の強
度を十分に強くする必要が有る。このため微細な磁気記
録媒体の磁界に対応して、磁性体１１０を微細にする必
要性がある。しかし第１インダクタンス素子１１１及び
第２インダクタンス素子１１２の微細化には限度が有
り、磁性体１１０の高度な微細化は困難で、漏洩磁界が
微細な超高密度磁気記録媒体の読み取りは極めて困難で
ある。Various magnetic heads have been proposed. FIG. 8 shows an example of conventional technology, which is disclosed in Japanese Patent Laid-Open No.
The structure of the magnetic reproducing apparatus described in Japanese Patent Publication No. 8-68205 is shown. In the magnetic reproducing apparatus shown in FIG. 8, there is a magnetic body 110, and there are a first inductance element 111 and a second inductance element 112 coupled to the magnetic body 110, which constitutes a magnetic head. The first inductance element 111 constitutes a primary side resonance circuit together with the capacitor 114, and
Connected to 17. The second inductance element 112 constitutes a secondary side tuning circuit together with the capacitor 118, and is connected to the detection circuit 120. This magnetic head utilizes the change in the high frequency magnetic permeability of the magnetic body 110. Although this magnetic head can obtain a high output, it is necessary to sufficiently increase the strength of the magnetic field caused by the magnetic recording medium 113 in the entire magnetic body 110. For this reason, it is necessary to make the magnetic body 110 fine according to the magnetic field of the fine magnetic recording medium. However, there is a limit to miniaturization of the first inductance element 111 and the second inductance element 112, it is difficult to highly miniaturize the magnetic body 110, and it is extremely difficult to read an ultra-high density magnetic recording medium having a minute leakage magnetic field. is there.
【０００４】この改良例として、特公平３−４４３６１
号公報記載の磁気記録再生装置があり、図９に示す構造
を有している。図９において、磁性体Ｍ1 は図示のよう
な開磁路構造であるため、磁気記録媒体１０３に起因す
る検知磁界は、磁気記録媒体１０３から離れるにつれて
急速に減衰する。このため、検知磁界は主として磁気記
録媒体に近接する部分の第１の磁性体Ｍ1 に印加され
る。第１の磁性体Ｍ1 にはコイルが巻回され、第１のイ
ンダクタンス素子Ｌ1 を構成している。そして、コイル
１０２を有する第２の磁性体Ｍ2 があり、第２のインダ
クタンス素子Ｌ2を構成している。この第２のインダク
タンス素子Ｌ2 は第１のインダクタンス素子Ｌ1 と電磁
気的に結合されており、第２のインダクタンス素子Ｌ2
から第１のインダクタンス素子Ｌ1 に誘起された高周波
信号の変化を検知するものであり、第１のインダクタン
ス素子Ｌ1 に含まれる第１の磁性体Ｍ1 とは別体の第２
のインダクタンス素子Ｌ2 に含まれる磁性体Ｍ2 があ
る。この改良例では別体の磁性体Ｍ2 には二次側のイン
ダクタンス素子Ｌ2 用のコイルが巻回されるのみである
ため、磁性体Ｍ2 の小形化が可能である。しかし、実用
に耐える性能を持ち、かつ、ミクロン〜サブミクロンの
コイルを形成することは困難で、なおミクロン〜サブミ
クロンの微小な磁界を検知することは極めて困難であ
る。また、磁性体を微小にした場合には磁区構造に乱れ
が生じやすく、信号強度の低下や、バルクハウゼンノイ
ズ等の増加が生じやすく、Ｓ／Ｎ比の点で問題があっ
た。さらに、磁性体Ｍ1 とＭ2 とを別体としたことで、
磁気ギャップによる磁気抵抗の増加が有り、検知される
高周波磁界の振幅が低下し、高周波領域では必ずしも高
感度化に寄与しなかった。このため微小領域の磁界を検
知する磁気ヘッドの実現には問題があった。As an example of this improvement, Japanese Patent Publication No. 3-44361.
There is a magnetic recording / reproducing apparatus described in Japanese Patent Publication No. JP-A-2003-96, which has a structure shown in FIG. In FIG. 9, since the magnetic body M 1 has an open magnetic circuit structure as shown in the figure, the detection magnetic field caused by the magnetic recording medium 103 is rapidly attenuated as it is separated from the magnetic recording medium 103. Therefore, the detection magnetic field is mainly applied to the first magnetic body M 1 in the vicinity of the magnetic recording medium. A coil is wound around the first magnetic body M 1 to form a first inductance element L 1 . Then, there is the second magnetic body M 2 having the coil 102, and constitutes the second inductance element L 2 . The second inductance element L 2 is electromagnetically coupled to the first inductance element L 1 and the second inductance element L 2
From is intended to detect the change of the first inductance element L 1 to the induced high frequency signal, a second first separate from the magnetic body M 1 included in the first inductance element L 1
There is a magnetic body M 2 included in the inductance element L 2 . In this improved example, only the coil for the secondary-side inductance element L 2 is wound around the separate magnetic body M 2 , so that the magnetic body M 2 can be miniaturized. However, it is difficult to form a coil of micron to sub-micron having a performance that can withstand practical use, and it is extremely difficult to detect a minute magnetic field of micron to sub-micron. Further, when the magnetic material is made minute, the magnetic domain structure is likely to be disturbed, the signal strength is lowered, and Barkhausen noise and the like are easily increased, which is a problem in terms of S / N ratio. Furthermore, by making the magnetic bodies M 1 and M 2 separate,
There was an increase in the magnetic resistance due to the magnetic gap, and the amplitude of the detected high-frequency magnetic field decreased, which did not necessarily contribute to higher sensitivity in the high-frequency region. Therefore, there is a problem in realizing a magnetic head that detects a magnetic field in a minute area.
【０００５】また、上記従来例を磁気記録媒体の読み取
りに使用する場合では、高周波磁界が磁極から漏洩する
ため、ノイズの原因や磁気記録媒体の交流消去が懸念さ
れる。このため、高周波磁界の強度を上げ、検出感度を
上昇させることには一定の限界が有った。また、バイア
ス磁界を印加した場合、バイアス磁界が磁極から漏洩
し、磁気記録媒体に好ましくない磁界を印加するという
問題あった。Further, when the above-mentioned conventional example is used for reading a magnetic recording medium, a high frequency magnetic field leaks from the magnetic pole, which may cause noise and AC erasing of the magnetic recording medium. Therefore, there is a certain limit in increasing the strength of the high frequency magnetic field and increasing the detection sensitivity. Further, when the bias magnetic field is applied, the bias magnetic field leaks from the magnetic pole, which causes an undesirable magnetic field to be applied to the magnetic recording medium.
【０００６】[0006]
【発明が解決しようとする課題】本発明は上記事情に鑑
みなされたものであって、請求項１に記載の発明におけ
る目的は、超高密度磁気記録媒体等の微小磁界にも対応
可能な高感度、高Ｓ／Ｎ比を有する再生用の新規な磁気
ヘッドの提供にある。SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a magnetic recording medium having a high magnetic field capable of coping with a minute magnetic field such as an ultra high density magnetic recording medium. It is to provide a novel magnetic head for reproduction having high sensitivity and a high S / N ratio.
【０００７】請求項２に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、特に、高周波領域の検出出力の低下を抑制するこ
とを目的としている。An object of the present invention according to claim 2 is to provide a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio capable of coping with a minute magnetic field such as an ultra high density magnetic recording medium. The purpose is to suppress a decrease in detection output in a high frequency region.
【０００８】請求項３に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、特に、高周波領域の渦電流損失に起因する検出出
力の低下を防止することを目的としている。An object of the present invention according to claim 3 is to provide a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio capable of coping with a minute magnetic field of an ultra high density magnetic recording medium, and particularly, The purpose is to prevent the detection output from decreasing due to eddy current loss in the high frequency range.
【０００９】請求項４に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、高周波磁界印加用部材の形成コストの低下を目的
としている。According to a fourth aspect of the present invention, there is provided a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio capable of coping with a minute magnetic field such as an ultra high density magnetic recording medium, and a high frequency magnetic field. The purpose is to reduce the cost of forming the applying member.
【００１０】請求項５に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、バイアス磁界印加用部材の形成コスト低下を目的
としている。An object of the present invention is to provide a bias magnetic field in a novel reproducing magnetic head having a high sensitivity and a high S / N ratio, which can cope with a minute magnetic field such as an ultra high density magnetic recording medium. The purpose is to reduce the cost of forming the applying member.
【００１１】請求項６に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、検知磁界の精度の向上、及び検知磁界の最大値を
可変とし、検知磁界のダイナミックレンジを拡張するこ
とを目的としている。An object of the present invention according to claim 6 is to provide a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio capable of coping with a minute magnetic field such as an ultra high density magnetic recording medium. The purpose of this is to improve the accuracy of and to make the maximum value of the detection magnetic field variable so as to extend the dynamic range of the detection magnetic field.
【００１２】請求項７に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、バイアス磁界に起因する高周波特性の劣化を、高
度に抑制することを目的としている。An object of the present invention is to provide a bias magnetic field in a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio, which can cope with a minute magnetic field such as an ultra high density magnetic recording medium. The purpose is to highly suppress the deterioration of the high-frequency characteristics due to.
【００１３】請求項８に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比であり、検知磁界の精度に優れ、検知磁
界ダイナミックレンジが幅広いことを特徴とする再生用
の新規な磁気ヘッドにおいて、形成コストの低下を目的
としている。An object of the present invention is to have a high sensitivity and a high S / N ratio capable of coping with a minute magnetic field of an ultra-high density magnetic recording medium and the like, which is excellent in the accuracy of the detection magnetic field and the dynamic detection magnetic field. A novel magnetic head for reproduction, which has a wide range, is intended to reduce the formation cost.
【００１４】請求項９に記載の発明における目的は、超
高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、高周波磁界の漏洩に起因する信号出力の低下を抑
制することを目的としている。An object of the present invention is to provide a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio capable of coping with a minute magnetic field of an ultra high density magnetic recording medium, and a high frequency magnetic field. The purpose is to suppress the decrease in the signal output due to the leakage of the.
【００１５】請求項１０に記載の発明における目的は、
超高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、磁気記録媒体への悪影響を抑制すること、及び、
Ｓ／Ｎ比の向上を目的としている。The object of the invention described in claim 10 is to:
In a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio capable of coping with a minute magnetic field of an ultra-high density magnetic recording medium and the like, suppressing adverse effects on the magnetic recording medium, and
The purpose is to improve the S / N ratio.
【００１６】請求項１１に記載の発明における目的は、
超高密度磁気記録媒体等の微小磁界にも対応可能な高感
度、高Ｓ／Ｎ比を有する再生用の新規な磁気ヘッドにお
いて、検知磁界の向きの判別を可能とすることを目的と
している。The object of the invention described in claim 11 is to:
It is an object of the present invention to make it possible to determine the direction of a detected magnetic field in a novel magnetic head for reproduction having a high sensitivity and a high S / N ratio that can cope with a minute magnetic field such as an ultra high density magnetic recording medium.
【００１７】請求項１２に記載の発明における目的は、
超高密度磁気記録媒体等の微小磁界にも対応可能であ
り、かつ、検知磁界の向きの判別が可能な高感度、高Ｓ
／Ｎ比を有する再生用の新規な磁気ヘッドにおいて、形
成コストの低下を目的としている。The object of the invention of claim 12 is to:
High sensitivity and high S that can be applied to a very small magnetic field such as an ultra high density magnetic recording medium and can discriminate the direction of the detected magnetic field.
A novel reproducing magnetic head having an A / N ratio aims to reduce the formation cost.
【００１８】請求項１３に記載の発明における目的は、
超高密度磁気記録媒体等の微小磁界にも対応可能であ
り、かつ、検知磁界の向きの判別が可能な高感度、高Ｓ
／Ｎ比を有する再生用の新規な磁気ヘッドにおいて、磁
界検知の精度向上を目的としている。The object of the invention set forth in claim 13 is to:
High sensitivity and high S that can be applied to a very small magnetic field such as an ultra high density magnetic recording medium and can discriminate the direction of the detected magnetic field.
The purpose of the present invention is to improve the accuracy of magnetic field detection in a new magnetic head for reproduction having an / N ratio.
【００１９】請求項１４に記載の発明における目的は、
超高密度磁気記録媒体等の微小磁界にも対応可能であ
り、かつ、検知磁界の向きの判別が可能な高感度、高Ｓ
／Ｎ比を有する再生用の新規な磁気ヘッドにおいて、媒
体の磁気情報の読み取りによる減衰を防止することを目
的としている。The object of the invention described in claim 14 is to:
High sensitivity and high S that can be applied to a very small magnetic field such as an ultra high density magnetic recording medium and can discriminate the direction of the detected magnetic field.
It is an object of the present invention to prevent the attenuation due to the reading of magnetic information of a medium in a new reproducing magnetic head having an / N ratio.
【００２０】請求項１５に記載の発明における目的は、
超高密度磁気記録媒体等の微小磁界にも対応可能であ
り、かつ、検知磁界の向きの判別が可能な高感度、高Ｓ
／Ｎ比を有する再生用の新規な磁気ヘッドにおいて、電
磁ノイズの発生防止及び外部の電磁ノイズによる誤作動
を防止すること、そして、さらにこの磁気ヘッドに近接
配列に適する特性を付加することを目的としている。The object of the invention of claim 15 is to:
High sensitivity and high S that can be applied to a very small magnetic field such as an ultra high density magnetic recording medium and can discriminate the direction of the detected magnetic field.
To prevent generation of electromagnetic noise and malfunctions due to external electromagnetic noise in a new magnetic head for reproduction having an A / N ratio, and to add characteristics suitable for proximity arrangement to this magnetic head. I am trying.
【００２１】[0021]
【課題を解決するための手段】本発明の請求項１記載の
磁気ヘッドでは、検知磁界に対応する磁極を有する第一
の磁路（以下、磁路（１）と記す）と、この磁路（１）
と交差する第二の磁路（以下、磁路（２）と記す）があ
る。磁路（１）には検知磁界が導入される。磁路（１）
及び磁路（２）は、強磁性金属、合金、これらの元素を
含む窒化物、あるいはフェライトやＹＩＧ（イットリウ
ム・鉄・ガーネット）等の化合物の磁性体、あるいはそ
れらの組合わせであり、公知の磁性体で構成される。磁
路（２）の構造は閉磁路であるが、開磁路構造も可能で
ある。In a magnetic head according to claim 1 of the present invention, a first magnetic path (hereinafter referred to as magnetic path (1)) having a magnetic pole corresponding to a detection magnetic field, and this magnetic path. (1)
There is a second magnetic path (hereinafter referred to as magnetic path (2)) intersecting with. A detection magnetic field is introduced into the magnetic path (1). Magnetic path (1)
The magnetic path (2) is a ferromagnetic metal, an alloy, a nitride containing these elements, a magnetic substance of a compound such as ferrite or YIG (yttrium, iron, garnet), or a combination thereof, and is known. Composed of magnetic material. The structure of the magnetic path (2) is a closed magnetic circuit, but an open magnetic circuit structure is also possible.
【００２２】そして、磁路（２）に高周波磁界を印加す
る高周波磁界印加用部材が、磁路（２）と電磁的に結合
されている。高周波磁界印加用部材は、高周波電源に接
続される導電部材や、高周波電磁場が導入される導波路
等である。磁路（２）が導電性を有する場合には、必要
に応じ電気的絶縁部材が付加される。高周波磁界の周波
数は磁路（２）の強磁性共鳴周波数の近傍もしくは強磁
性共鳴周波数未満の周波数領域に有る。具体的には、数
ｋＨｚ〜数１０ＧＨｚの範囲に有る。A high frequency magnetic field applying member for applying a high frequency magnetic field to the magnetic path (2) is electromagnetically coupled to the magnetic path (2). The high-frequency magnetic field applying member is a conductive member connected to a high-frequency power source, a waveguide into which a high-frequency electromagnetic field is introduced, or the like. When the magnetic path (2) has conductivity, an electrically insulating member is added if necessary. The frequency of the high-frequency magnetic field is in the vicinity of the ferromagnetic resonance frequency of the magnetic path (2) or in the frequency region below the ferromagnetic resonance frequency. Specifically, it is in the range of several kHz to several tens GHz.
【００２３】磁路（１）と磁路（２）との交差部を磁界
変調部という。この意味は、磁界変調部において、磁気
記録媒体に起因する磁界と高周波磁界印加用部材に起因
する高周波磁界とが交差する構造である。磁界変調部の
磁性体の飽和磁束密度は、磁界変調部近傍に存在する磁
路（２）のそれより低い値をとる。磁界変調部の高周波
領域の透磁率は磁路（１）に導入される検知磁界により
変化する。磁界変調部は強磁性金属、合金、これらの元
素を含む窒化物、あるいはフェライトやＹＩＧ等の化合
物の磁性体、あるいはそれらの組合せであり、公知の磁
性体で構成される。磁性体の磁性は、強磁性、フェリ磁
性、寄生強磁性、超常磁性、らせん磁性、ミクト磁性等
のいずれかであるが、異なる磁性を示す磁性体を組合せ
てもよい。また、反強磁性体を下地層や上部磁性層、あ
るいは中間の磁性層として付随させても良い。The intersection of the magnetic path (1) and the magnetic path (2) is called a magnetic field modulator. This means a structure in the magnetic field modulator where the magnetic field originating from the magnetic recording medium and the high frequency magnetic field originating from the high frequency magnetic field applying member intersect. The saturation magnetic flux density of the magnetic body of the magnetic field modulation section takes a value lower than that of the magnetic path (2) existing near the magnetic field modulation section. The magnetic permeability of the high frequency region of the magnetic field modulator changes depending on the detection magnetic field introduced into the magnetic path (1). The magnetic field modulation unit is a ferromagnetic metal, an alloy, a nitride containing these elements, a magnetic body of a compound such as ferrite or YIG, or a combination thereof, and is composed of a known magnetic body. The magnetism of the magnetic substance is any of ferromagnetism, ferrimagnetism, parasitic ferromagnetism, superparamagnetism, spiral magnetism, Miktomagnetism, etc., but magnetic substances exhibiting different magnetism may be combined. Further, an antiferromagnetic material may be attached as an underlayer, an upper magnetic layer, or an intermediate magnetic layer.
【００２４】磁路（１）及び磁路（２）と磁界変調部と
の境界において、磁路（１）と磁界変調部及び磁路
（２）と磁界変調部とは磁気的に直接接続される。この
ため、磁路（１）と磁界変調部の磁性体が同種の場合に
は必ずしもその境界が明白でない場合も有る。なお、こ
の構造以外に、磁路（１）及び／または磁路（２）と磁
界変調部との境界において、単数または複数の微小ギャ
ップを有する構造も可能である。At the boundary between the magnetic path (1) and the magnetic path (2) and the magnetic field modulation section, the magnetic path (1) and the magnetic field modulation section and the magnetic path (2) and the magnetic field modulation section are magnetically directly connected. It Therefore, when the magnetic path (1) and the magnetic substance of the magnetic field modulation unit are of the same type, the boundary may not always be clear. In addition to this structure, a structure having a single or a plurality of minute gaps at the boundary between the magnetic path (1) and / or the magnetic path (2) and the magnetic field modulation section is also possible.
【００２５】磁界変調部を単磁区構造とするために、バ
イアス磁界がバイアス磁界印加用部材により印加され
る。バイアス磁界は高周波磁界と平行もしくは斜交して
いる。そして、高周波磁束検知用部材が磁路（２）に配
備される。高周波磁束検知用部材は、磁路（２）に電磁
的に結合されるコイルなどの導電部材に誘導される誘導
起電力を誘起し、高周波電界検知手段に接続可能なも
の、あるいは、磁気抵抗効果を利用し、高周波磁束やそ
の時間変化を検知するもの等があり、必要に応じ、検波
回路、共振回路やフィルターなどの電子回路が付加され
る。本発明の磁気ヘッドでは、高周波磁束検知用部材と
高周波磁界印加用部材との間に磁界変調部が存在する幾
何学的配置が採用され、磁界変調部の磁性体の透磁率変
化により高周波磁界の高周波磁界印加用部材から高周波
磁束検知用部材側への高周波磁束の伝播を変化させ得る
構造となっている。なお、磁気抵抗効果を用いる高周波
磁束検知用部材は、磁界変調部の抵抗率変化を測定する
ものでも良い。A bias magnetic field is applied by the bias magnetic field applying member so that the magnetic field modulator has a single domain structure. The bias magnetic field is parallel or oblique to the high frequency magnetic field. Then, the high frequency magnetic flux detecting member is arranged in the magnetic path (2). The high frequency magnetic flux detecting member induces an induced electromotive force induced in a conductive member such as a coil electromagnetically coupled to the magnetic path (2) and can be connected to the high frequency electric field detecting means, or a magnetoresistive effect. There is a device for detecting high-frequency magnetic flux and its change over time by utilizing, and electronic circuits such as a detection circuit, a resonance circuit and a filter are added if necessary. The magnetic head of the present invention adopts a geometrical arrangement in which a magnetic field modulation section exists between the high frequency magnetic flux detection member and the high frequency magnetic field application member, and the magnetic field of the high frequency magnetic field changes due to the change in the magnetic permeability of the magnetic body of the magnetic field modulation section. The structure is such that the propagation of the high frequency magnetic flux from the high frequency magnetic field applying member to the high frequency magnetic flux detecting member side can be changed. The high-frequency magnetic flux detecting member that uses the magnetoresistive effect may be one that measures the change in resistivity of the magnetic field modulation unit.
【００２６】本発明の請求項２の磁気ヘッドでは、本発
明の請求項１の磁気ヘッドにおいて、高周波透磁率を高
めるために磁路（２）の磁界変調部近傍を一軸異方性を
有する磁性体で構成し、この磁化容易軸を高周波磁界に
対し垂直とする。すなわち、磁路（２）を構成する磁性
体の全てまたは磁界変調部近傍のみを一軸異方性を有す
る磁性体で構成し、この磁化容易軸を高周波磁界に対し
垂直とする。バイアス磁界が磁路（２）を通過する場合
には、磁路（２）におけるバイアス磁界が磁路（２）の
異方性磁界を上回らない範囲のバイアス磁界が印加され
る。According to a second aspect of the present invention, there is provided the magnetic head according to the first aspect of the present invention, in which the magnetic field (2) has a uniaxial anisotropy in the vicinity of the magnetic field modulation portion in order to enhance high frequency permeability. It is composed of a body, and its easy axis is perpendicular to the high-frequency magnetic field. That is, all of the magnetic substance forming the magnetic path (2) or only the vicinity of the magnetic field modulation portion is made of a magnetic substance having uniaxial anisotropy, and this easy axis of magnetization is perpendicular to the high frequency magnetic field. When the bias magnetic field passes through the magnetic path (2), the bias magnetic field in the range in which the bias magnetic field in the magnetic path (2) does not exceed the anisotropic magnetic field in the magnetic path (2) is applied.
【００２７】本発明の請求項３の磁気ヘッドでは、本発
明の請求項１または請求項２による磁気ヘッドにおい
て、磁路（２）を絶縁層により隔てられた多層構造の強
磁性金属とすることを特徴としている。According to a third aspect of the present invention, in the magnetic head according to the first or second aspect of the present invention, the magnetic path (2) is a ferromagnetic metal having a multi-layer structure separated by an insulating layer. Is characterized by.
【００２８】本発明の請求項４の磁気ヘッドでは、本発
明の請求項１，２または３の磁気ヘッドにおいて、高周
波磁界印加用部材が磁路（２）に巻回されるコイルを有
していることを特徴としており、このコイルは高周波電
源に接続される構造を有している。According to a fourth aspect of the present invention, in the magnetic head according to the first, second or third aspect of the present invention, the high frequency magnetic field applying member has a coil wound around the magnetic path (2). This coil has a structure to be connected to a high frequency power source.
【００２９】本発明の請求項５の磁気ヘッドでは、本発
明の請求項１，２，３または４の磁気ヘッドにおいて、
バイアス磁界印加用部材が永久磁石を有していることを
特徴としている。According to a fifth aspect of the present invention, in the magnetic head according to the first, second, third or fourth aspect of the present invention,
It is characterized in that the bias magnetic field applying member has a permanent magnet.
【００３０】本発明の請求項６の磁気ヘッドでは、本発
明の請求項１，２，３，４または５において、バイアス
磁界印加用部材が単数または複数の直流磁界発生用のコ
イルを有していることを特徴としており、このコイルに
は直流電流が通電される。According to a sixth aspect of the present invention, in the magnetic head according to the first, second, third, fourth or fifth aspect of the present invention, the bias magnetic field applying member has a single or a plurality of DC magnetic field generating coils. A direct current is passed through this coil.
【００３１】本発明の請求項７の磁気ヘッドでは、本発
明の請求項５または６の磁気ヘッドにおいて、バイアス
磁界印加用部材がバイアス磁界印加用の第三の磁路（以
下、磁路（３）と記す）を有していることを特徴として
いる。According to a seventh aspect of the present invention, in the magnetic head according to the fifth or sixth aspects of the present invention, the bias magnetic field applying member is a third magnetic path for applying the bias magnetic field (hereinafter, magnetic path (3 ))).
【００３２】本発明の請求項８の磁気ヘッドでは、本発
明の請求項６の磁気ヘッドにおいて、バイアス磁界印加
用部材が磁路（２）に巻回される直流磁界発生用のコイ
ルを有することを特徴としている。According to an eighth aspect of the present invention, in the magnetic head according to the sixth aspect of the present invention, the bias magnetic field applying member has a coil for generating a DC magnetic field wound around the magnetic path (2). Is characterized by.
【００３３】本発明の請求項９の磁気ヘッドでは、本発
明の請求項４及び８による磁気ヘッドにおいて、磁界変
調部と高周波磁界印加用部材との磁路（２）に沿う磁路
長の最短距離が、磁界変調部とバイアス磁界印加用部材
との磁路（２）に沿う磁路長の最短距離より小さいこと
を特徴としている。According to a ninth aspect of the present invention, in the magnetic head according to the fourth and eighth aspects of the present invention, the shortest magnetic path length along the magnetic path (2) between the magnetic field modulation section and the high frequency magnetic field applying member. The distance is smaller than the shortest distance of the magnetic path length along the magnetic path (2) between the magnetic field modulator and the bias magnetic field applying member.
【００３４】本発明の請求項１０の磁気ヘッドでは、本
発明の請求項１，２，３，４，５，６，７，８または９
の磁気ヘッドにおいて、磁路（１）と磁路（２）とを磁
界変調部において直交させることを特徴としている。The magnetic head according to claim 10 of the present invention is the magnetic head according to claim 1, 2, 3, 4, 5, 6, 7, 8 or 9 of the present invention.
The magnetic head (1) is characterized in that the magnetic path (1) and the magnetic path (2) are made orthogonal to each other in the magnetic field modulator.
【００３５】本発明の請求項１１の磁気ヘッドでは、本
発明の請求項１，２，３，４，５，６，７，８，９また
は１０の磁気ヘッドにおいて、検知磁界が０の状態での
磁界変調部の磁化の向きを、高周波磁界の向きに対し非
平行とすることを特徴としている。According to claim 11 of the present invention, in the magnetic head according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 of the present invention, the detection magnetic field is 0. It is characterized in that the direction of magnetization of the magnetic field modulator is non-parallel to the direction of the high frequency magnetic field.
【００３６】本発明の請求項１２の磁気ヘッドでは、本
発明の請求項１１の磁気ヘッドにおいて、結晶磁気異方
性、誘導磁気異方性、または形状磁気異方性、あるいは
これらの組合わせの作用により、磁界変調部の磁性体の
磁化容易軸を高周波磁界に対し非平行とし、かつ、磁化
困難軸を高周波磁界に対し非平行とすることを特徴とし
ている。According to a twelfth aspect of the present invention, in the magnetic head according to the eleventh aspect of the present invention, the crystalline magnetic anisotropy, the induced magnetic anisotropy, the shape magnetic anisotropy, or a combination thereof is used. Due to the action, the easy axis of magnetization of the magnetic material of the magnetic field modulation section is made non-parallel to the high frequency magnetic field, and the hard axis of magnetization is made non-parallel to the high frequency magnetic field.
【００３７】本発明の請求項１３の磁気ヘッドでは、本
発明の請求項１１の磁気ヘッドにおいて、バイアス磁界
印加用部材が磁路（１）に巻回される直流バイアス磁界
発生用のコイルを有することを特徴としている。According to a thirteenth aspect of the present invention, in the magnetic head according to the eleventh aspect of the present invention, the bias magnetic field applying member has a coil for generating a DC bias magnetic field wound around the magnetic path (1). It is characterized by that.
【００３８】本発明の請求項１４の磁気ヘッドでは、本
発明の請求項１，２，３，４，５，６，７，８，９，１
０，１１，１２または１３の磁気ヘッドにおいて、高周
波磁界印加用部材の駆動周波数が磁路（１）の強磁性共
鳴周波数を上回ることを特徴としている。According to the magnetic head of claim 14 of the present invention, the magnetic heads of claims 1, 2, 3, 4, 5, 6, 7, 8, 9, 1 of the present invention are provided.
The magnetic head of 0, 11, 12 or 13 is characterized in that the driving frequency of the high frequency magnetic field applying member exceeds the ferromagnetic resonance frequency of the magnetic path (1).
【００３９】本発明の請求項１５の磁気ヘッドでは、本
発明の請求項１，２，３，４，５，６，７，８，９，１
０，１１，１２，１３または１４の磁気ヘッドにおい
て、高周波磁界印加用部材及び磁路（２）の周囲に高透
磁率導電体からなるシールド手段を配備することを特徴
としている。In the magnetic head of claim 15 of the present invention, the magnetic heads of claims 1, 2, 3, 4, 5, 6, 7, 8, 9, 1 of the present invention are provided.
The magnetic head of 0, 11, 12, 13 or 14 is characterized in that a shield means made of a high magnetic permeability conductor is provided around the high frequency magnetic field applying member and the magnetic path (2).
【００４０】[0040]
【作用】本発明による磁気ヘッドでは、磁路（１）の内
部に記録媒体等からの検知磁界が導入される。検知磁界
の磁路内部の強度分布は、基本的には、検知磁界の起磁
力、検知磁界の周波数領域での磁路（１）の透磁率、及
び、磁界変調部の透磁率の分布に応じたものとなる。ま
た、高周波磁界印加用部材により磁路（２）内に検知磁
界の周波数を上回る周波数を有する高周波磁界が発生す
る。この高周波磁界の強度分布は、基本的には、高周波
磁界印加用部材による起磁力と磁気回路を構成する各部
分の磁気特性に応じたものとなる。高周波磁界はその場
所の磁路（２）と概ね平行である。磁界変調部の磁性体
の高周波領域の透磁率は、検波磁界により変化する。こ
のため、検知磁界の値もしくはその変化は、高周波磁束
検知用部材を用い検知される高周波磁束の振幅及び／ま
たは位相の変化を検知することにより検知することがで
きる。従って、これらの検知により記録媒体等に記録さ
れた磁気情報を再生することができる。In the magnetic head according to the present invention, the detection magnetic field from the recording medium or the like is introduced inside the magnetic path (1). The intensity distribution inside the magnetic path of the detection magnetic field basically depends on the magnetomotive force of the detection magnetic field, the permeability of the magnetic path (1) in the frequency domain of the detection magnetic field, and the distribution of the magnetic permeability of the magnetic field modulator. It becomes a thing. Further, the high frequency magnetic field applying member generates a high frequency magnetic field having a frequency higher than the frequency of the detection magnetic field in the magnetic path (2). The intensity distribution of the high-frequency magnetic field basically corresponds to the magnetomotive force of the high-frequency magnetic field applying member and the magnetic characteristics of each part constituting the magnetic circuit. The high frequency magnetic field is generally parallel to the magnetic path (2) at that location. The magnetic permeability of the magnetic material of the magnetic field modulator in the high frequency region changes depending on the detected magnetic field. Therefore, the value of the detection magnetic field or the change thereof can be detected by detecting the change in the amplitude and / or the phase of the high frequency magnetic flux detected using the high frequency magnetic flux detecting member. Therefore, the magnetic information recorded on the recording medium or the like can be reproduced by these detections.
【００４１】次に図面を参照して本発明による磁気ヘッ
ドの検出原理について説明する。図３は外部磁界Ｈが０
の状態で磁界変調部１３の磁化が磁路（２）１２に平行
な角度関係となる場合の、磁界変調部１３近傍の磁路の
主要磁区の磁化の状態の概略を示す概念図である。この
状態は磁気異方性の無い磁性材料で磁界変調部１３を構
成し、磁路（２）１２に平行なバイアス磁界を印加した
場合に実現される。なお、図３は、磁路（１）１１及び
磁路（２）１２を一軸磁気異方性を有する磁性材料で構
成した場合に対応するが、磁界変調部１３に関する以下
の議論は、磁路（１）及び磁路（２）が等方的な磁気的
性質やこれ以外の磁気異方性を有する場合にも成立す
る。また、図３で、磁路（２）１２の断面積は磁界変調
部近傍で小さくなっているが、これ以外の場合も同様の
議論が成立する。なお、図３の矢印は磁性体の磁化の方
向を示す。バイアス磁界の作用により磁界変調部１３の
磁性体は単磁区構造となる。図３では磁路（２）と磁界
変調部１３の磁化は平行な角度関係に有り、従って高周
波磁界と平行である。一方、磁路（２）１２の磁性体は
バイアス磁界に対し未飽和であり、高周波磁界に対して
非平行な角度関係に有る。Next, the principle of detection of the magnetic head according to the present invention will be described with reference to the drawings. In FIG. 3, the external magnetic field H is 0
9 is a conceptual diagram schematically showing a state of magnetization of a main magnetic domain of a magnetic path in the vicinity of the magnetic field modulation unit 13 when the magnetization of the magnetic field modulation unit 13 has an angular relationship parallel to the magnetic path (2) 12 in the state of FIG. This state is realized when the magnetic field modulator 13 is made of a magnetic material having no magnetic anisotropy and a bias magnetic field parallel to the magnetic path (2) 12 is applied. Note that FIG. 3 corresponds to the case where the magnetic path (1) 11 and the magnetic path (2) 12 are made of a magnetic material having uniaxial magnetic anisotropy. This also applies when (1) and the magnetic path (2) have isotropic magnetic properties and other magnetic anisotropy. Further, in FIG. 3, the cross-sectional area of the magnetic path (2) 12 is small in the vicinity of the magnetic field modulation portion, but the same argument holds in other cases. The arrow in FIG. 3 indicates the direction of magnetization of the magnetic material. Due to the action of the bias magnetic field, the magnetic body of the magnetic field modulation unit 13 has a single domain structure. In FIG. 3, the magnetic path (2) and the magnetization of the magnetic field modulation unit 13 have a parallel angular relationship, and thus are parallel to the high frequency magnetic field. On the other hand, the magnetic substance of the magnetic path (2) 12 is unsaturated with respect to the bias magnetic field, and has a non-parallel angular relationship with the high frequency magnetic field.
【００４２】強磁性共鳴の周波数近傍もしくはこれ以下
の周波数領域で、磁性体の高周波透磁率は、磁性体の磁
化の向きと高周波磁界とのなす角度に依存し、かつ、反
磁界や磁気異方性の効果を考慮に入れた磁性体内部のス
ピンに対して作用する実効的な磁界の強度に依存する。
磁化の向きに関しては、高周波磁界の向きと磁化の向き
が平行である場合には透磁率は最小で、垂直である場合
に再大となる。また、磁性体内の磁性体内部の実効的な
磁界が強く、磁化に対する束縛力が大きいほど透磁率は
減少し、強磁性共鳴周波数は上昇する。このため、本発
明での磁界変調部１３の高周波透磁率（実数部）はバイ
アス磁界の作用により低下する。しかし、磁路（２）１
２の飽和磁束密度が磁界変調部１３より大きいために、
バイアス磁界の作用による磁路（２）１２の磁化の角度
変化は著しいものではなく、高周波透磁率のバイアス磁
界による低下率は磁界変調部１３と比較して小さい。即
ちバイアス磁界が磁路（２）１２に対し作用した場合に
おいても、磁路（２）１２の磁区の基本構造は変化せ
ず、高周波磁界に対する高い透磁率（実数部）を維持で
きる。In the frequency region near or below the frequency of the ferromagnetic resonance, the high frequency magnetic permeability of the magnetic material depends on the angle formed by the magnetization direction of the magnetic material and the high frequency magnetic field, and the demagnetizing field and magnetic anisotropy. It depends on the strength of the effective magnetic field that acts on the spins inside the magnetic body, taking into consideration the effect of the magnetic properties.
Regarding the direction of magnetization, the magnetic permeability is minimum when the direction of the high-frequency magnetic field and the direction of magnetization are parallel, and re-increased when the direction is perpendicular. Further, as the effective magnetic field inside the magnetic body is stronger and the binding force for the magnetization is larger, the magnetic permeability is decreased and the ferromagnetic resonance frequency is increased. Therefore, the high-frequency permeability (real part) of the magnetic field modulator 13 in the present invention is lowered by the action of the bias magnetic field. However, magnetic path (2) 1
Since the saturation magnetic flux density of 2 is larger than the magnetic field modulator 13,
The angle change of the magnetization of the magnetic path (2) 12 due to the action of the bias magnetic field is not remarkable, and the reduction rate of the high frequency magnetic permeability due to the bias magnetic field is smaller than that of the magnetic field modulator 13. That is, even when the bias magnetic field acts on the magnetic path (2) 12, the basic structure of the magnetic domain of the magnetic path (2) 12 does not change, and a high magnetic permeability (real part) to the high frequency magnetic field can be maintained.
【００４３】上記の状態で磁路（１）１１を介して磁界
変調部１３に検知磁界が作用すると、磁界変調部１３の
磁化は、検知磁界の強度に応じてその角度を変化させ
る。図４に検知磁界が作用した状態での磁界変調部１３
の主要磁区構造の概念図を示す。なお、検知磁界の周波
数は、磁路（１）１１、磁路（２）１２、及び磁界変調
部１３の強磁性共鳴周波数未満の領域にある。磁路
（１）１１を介し検知磁界に起因する磁界が磁界変調部
１３に印加されるため、磁界変調部１３の磁化は検知磁
界の強度変化に対応してその角度を変化させる。磁化の
回転角度は検知磁界とバイアス磁界との比に応じたもの
となる。なお、上述したように、検知磁界の周波数は強
磁性共鳴未満の周波数範囲に有るため検知磁界と磁化の
回転との位相差は無視できる。この状態で高周波磁界が
重畳されると、磁界変調部１３の磁化は、検知磁界の周
波数で緩やかに変位する成分と、高周波の領域で変位す
る成分とが重畳された挙動を示す。ここで、高周波領域
の変位の振幅は、検知磁界に起因する磁化の回転角に依
存する。また、検知磁界の強度が強いほど高周波磁界と
磁界変調部１３の磁化とのなす角が大きくなるため、磁
界変調部１３の高周波透磁率の実数部は大きなものとな
るが、これにより高周波磁束検知手段により検知される
高周波磁束の振幅は増加する。即ち、高周波磁束検知手
段により検知される高周波磁束の振幅は検知磁界の絶対
値の増加と共に増加するものとなる。なお、検知可能な
磁界の上限は、バイアス磁界の強度に依存する。従っ
て、強い磁界を検知する場合には、これに対応してバイ
アス磁界の強度を増加させる。When the detection magnetic field acts on the magnetic field modulation section 13 via the magnetic path (1) 11 in the above state, the magnetization of the magnetic field modulation section 13 changes its angle according to the strength of the detection magnetic field. FIG. 4 shows the magnetic field modulator 13 in the state where the detection magnetic field acts.
The conceptual diagram of the main magnetic domain structure of is shown. The frequency of the detected magnetic field is in the region below the ferromagnetic resonance frequency of the magnetic path (1) 11, the magnetic path (2) 12, and the magnetic field modulation unit 13. Since the magnetic field resulting from the detection magnetic field is applied to the magnetic field modulation unit 13 via the magnetic path (1) 11, the magnetization of the magnetic field modulation unit 13 changes its angle in response to the change in the strength of the detection magnetic field. The rotation angle of the magnetization depends on the ratio between the detection magnetic field and the bias magnetic field. As described above, since the frequency of the detection magnetic field is in the frequency range below the ferromagnetic resonance, the phase difference between the detection magnetic field and the rotation of the magnetization can be ignored. When a high-frequency magnetic field is superimposed in this state, the magnetization of the magnetic field modulator 13 exhibits a behavior in which a component that is gently displaced at the frequency of the detection magnetic field and a component that is displaced in the high-frequency region are superimposed. Here, the amplitude of the displacement in the high frequency region depends on the rotation angle of the magnetization caused by the detection magnetic field. Further, since the angle formed by the high frequency magnetic field and the magnetization of the magnetic field modulation section 13 increases as the strength of the detection magnetic field increases, the real number part of the high frequency magnetic permeability of the magnetic field modulation section 13 becomes large. The amplitude of the high frequency magnetic flux detected by the means increases. That is, the amplitude of the high frequency magnetic flux detected by the high frequency magnetic flux detecting means increases as the absolute value of the detection magnetic field increases. The upper limit of the detectable magnetic field depends on the strength of the bias magnetic field. Therefore, when detecting a strong magnetic field, the intensity of the bias magnetic field is correspondingly increased.
【００４４】図５は検知磁界が０の状態で磁界変調部１
３の磁化が磁路（２）１２に対し斜交している場合の磁
界変調部１３近傍の主要磁区の構造を示す概念図であ
る。図５の磁化状態は、バイアス磁界を磁路（２）１２
に対し斜交して印加する。または、磁路（１）１１に平
行なバイアス磁界と磁路（２）１２に平行なバイアス磁
界とを重畳させる、あるいはバイアス磁界を磁路（２）
１２に平行とし、かつ、磁界変調部１３に形状磁気異方
性、結晶磁気異方性、誘導磁気異方性などの何らかの磁
気異方性を持たせ、バイアス磁界と磁化とを非平行な状
態とすることにより実現される。磁気異方性による場合
は、磁化容易軸を高周波磁界に対し非平行とし、かつ、
磁化困難軸を高周波磁界に対し非平行とする場合に、高
周波磁界と磁化との角度関係が一意に定まる。FIG. 5 shows the magnetic field modulation unit 1 when the detected magnetic field is zero.
6 is a conceptual diagram showing a structure of a main magnetic domain in the vicinity of the magnetic field modulation unit 13 when the magnetization of No. 3 obliquely intersects the magnetic path (2) 12. FIG. In the magnetization state of FIG. 5, the bias magnetic field is applied to the magnetic path (2) 12
The voltage is applied obliquely with respect to. Alternatively, the bias magnetic field parallel to the magnetic path (1) 11 and the bias magnetic field parallel to the magnetic path (2) 12 are superposed, or the bias magnetic field is applied to the magnetic path (2).
12 is parallel to the magnetic field modulator 12, and the magnetic field modulator 13 has some magnetic anisotropy such as shape magnetic anisotropy, crystal magnetic anisotropy, and induced magnetic anisotropy, so that the bias magnetic field and the magnetization are not parallel. It is realized by In the case of magnetic anisotropy, the easy axis of magnetization is not parallel to the high frequency magnetic field, and
When the hard magnetization axis is made non-parallel to the high frequency magnetic field, the angular relationship between the high frequency magnetic field and the magnetization is uniquely determined.
【００４５】図６は図５の磁化状態の磁界変調部１３に
検知磁界＋Ｈ0 が重畳された場合の主要磁区の概念図で
あり、また、図７は図５の磁化状態の磁界変調部１３
に、検知磁界−Ｈ0 が重畳された場合の主要磁区の概念
図である。高周波磁束検知手段に検知される高周波磁束
の振幅は、図６の場合に最も大きく、図７の場合に最も
小さい。即ち、−Ｈ0＜Ｈ＜＋Ｈ0の検知磁界の範囲で、
高周波磁束検知手段に検知される高周波磁束の振幅は検
知磁界の増加と共に単調に増加する。このため、高周波
磁界の振幅と検知磁界の値は１対１の対応関係となり、
磁化の向きの判定が可能となる。従って、磁化の向きに
よって２値化して記録するデジタル磁気記録媒体への対
応が可能となる。FIG. 6 is a conceptual diagram of the main magnetic domains when the detection magnetic field + H 0 is superposed on the magnetized magnetic field modulator 13 of FIG. 5, and FIG. 7 is the magnetized magnetic field modulator 13 of FIG.
FIG. 6 is a conceptual diagram of a main magnetic domain when a detection magnetic field −H 0 is superposed on the magnetic field. The amplitude of the high frequency magnetic flux detected by the high frequency magnetic flux detecting means is largest in the case of FIG. 6 and smallest in the case of FIG. 7. That is, in the range of the detection magnetic field of −H 0 <H <+ H 0 ,
The amplitude of the high frequency magnetic flux detected by the high frequency magnetic flux detecting means monotonically increases with an increase in the detection magnetic field. Therefore, there is a one-to-one correspondence between the amplitude of the high frequency magnetic field and the value of the detection magnetic field,
It is possible to determine the direction of magnetization. Therefore, it is possible to support a digital magnetic recording medium that is binarized and recorded depending on the direction of magnetization.
【００４６】好ましい磁路の磁気特性は、高周波領域で
の磁路（２）１２の透磁率の実数部分が高く、磁界変調
部１３の高周波透磁率の外部磁界による変化率が高く、
かつ、磁界変調部１３の高周波領域の透磁率の実数部分
は、磁路（２）１２の透磁率の実数部分より大幅に低い
ことである。さらに、良好な検知を行なうためには、磁
路（１）１１の検知磁界の周波数領域での透磁率の実数
部分を磁界変調部１３の透磁率の実数部分の最低値より
十分に高くすることが重要で、これにより磁界変調部１
３での検知磁界強度の低下を防止することができる。し
かし、磁界変調部１３の信号磁界の周波数領域での透磁
率の実数部を過度に低くすると、磁路（１）１１から検
知磁界の漏洩が生じ、信号強度の低下を招くため好まし
くない。The preferable magnetic characteristics of the magnetic path are that the real part of the magnetic permeability of the magnetic path (2) 12 in the high frequency region is high, the rate of change of the high frequency magnetic permeability of the magnetic field modulator 13 due to the external magnetic field is high,
Moreover, the real part of the magnetic permeability in the high frequency region of the magnetic field modulator 13 is significantly lower than the real part of the magnetic permeability of the magnetic path (2) 12. Furthermore, in order to perform good detection, the real part of the magnetic permeability in the frequency region of the detection magnetic field of the magnetic path (1) 11 should be sufficiently higher than the minimum value of the real part of the magnetic permeability of the magnetic field modulator 13. Is important.
It is possible to prevent a decrease in the detected magnetic field strength in No. 3. However, if the real part of the magnetic permeability of the magnetic field modulator 13 in the frequency domain of the signal magnetic field is excessively lowered, the detection magnetic field leaks from the magnetic path (1) 11 and the signal strength is reduced, which is not preferable.
【００４７】本発明による磁気ヘッドでは、信号磁界の
周波数を上回る周波数の高周波磁束を検知するため、高
感度な磁界検知が可能であるが、特に、高周波磁界と外
部磁界とが交差する磁界変調部の領域を微小なものとす
ることができるという特徴を有する。このため、磁界変
調部で大きな検知磁界強度を得ることが可能となる。こ
れは微小なＥＭＩ等の外部磁界によるノイズの影響を小
さなものとする作用を有し、さらに、磁界変調部の磁化
の回転を安定なものとすることができる。そして、高周
波磁束検知用部材には検知対象の磁束がほとんど浸入し
ないため、高周波磁束の検知を安定に行なうことができ
る。Since the magnetic head according to the present invention detects a high frequency magnetic flux having a frequency higher than the frequency of the signal magnetic field, a highly sensitive magnetic field can be detected. In particular, a magnetic field modulator where the high frequency magnetic field and the external magnetic field intersect. The feature is that the area of can be made minute. Therefore, it is possible to obtain a large detected magnetic field strength in the magnetic field modulation unit. This has a function of reducing the influence of noise due to an external magnetic field such as a minute EMI, and can further stabilize the rotation of the magnetization of the magnetic field modulation unit. Further, since the magnetic flux to be detected hardly penetrates into the high frequency magnetic flux detecting member, the high frequency magnetic flux can be detected stably.
【００４８】さらに、上述した磁界変調部の単磁区構造
は、バルクハウゼンノイズなどの発生を防止し、Ｓ／Ｎ
比の向上に寄与する。なお、磁化と高周波磁界が完全に
平行でない場合には、強磁性共鳴が生じるが、上述した
バイアス磁界は強磁性共鳴周波数を増加させる作用も有
する。そして、バイアス磁界により磁路のその他の部分
の高周波透磁率（実数部）を維持した状態で、磁界変調
部の透磁率（実数部）を大幅に低下させることが可能な
飽和磁束密度関係が実現されている。Furthermore, the above-mentioned single domain structure of the magnetic field modulating section prevents the occurrence of Barkhausen noise and the like, and S / N
It contributes to the improvement of the ratio. When the magnetization and the high-frequency magnetic field are not completely parallel, ferromagnetic resonance occurs, but the above-mentioned bias magnetic field also has the effect of increasing the ferromagnetic resonance frequency. Then, while maintaining the high frequency permeability (real part) of the other part of the magnetic path by the bias magnetic field, the saturation magnetic flux density relationship that can significantly reduce the permeability (real part) of the magnetic field modulation part is realized. Has been done.
【００４９】磁界変調部の透磁率と高周波磁束検知用部
材に検知される高周波磁束の振幅と位相に関しては以下
の傾向を有する。即ち、高周波磁束検知用部材に検知さ
れる高周波磁束の振幅は、磁界変調部の複素透磁率の実
数部分が低下する場合に低下し、この虚数部分が低下す
る場合に増加する傾向に有る。そして、複素透磁率の虚
数部分の変化は、検知される高周波磁束の位相を変化さ
せる。このため、本発明の高周波磁束の動作では、磁界
変調部の複素透磁率の実数部分、虚数部分の外部磁界依
存性、周波数依存性を考慮にいれる必要が有る。好まし
くは、上述した外部磁界の作用により、複素透磁率の実
数部分が増加する場合に虚数部分が減少する周波数、あ
るいは、透磁率の虚数部分が無視できる周波数で、高周
波磁界印加用部材を動作させるが、高周波透磁率の外部
磁界依存性において、実数部分と虚数部分の作用が相殺
する場合でもいずれか一方の作用が強ければ動作は可能
である。The magnetic permeability of the magnetic field modulator and the amplitude and phase of the high frequency magnetic flux detected by the high frequency magnetic flux detecting member have the following tendencies. That is, the amplitude of the high-frequency magnetic flux detected by the high-frequency magnetic flux detecting member tends to decrease when the real part of the complex magnetic permeability of the magnetic field modulator decreases, and increases when the imaginary part decreases. Then, the change of the imaginary part of the complex magnetic permeability changes the phase of the detected high frequency magnetic flux. Therefore, in the operation of the high frequency magnetic flux of the present invention, it is necessary to take into consideration the external magnetic field dependency and the frequency dependency of the real number part and the imaginary number part of the complex magnetic permeability of the magnetic field modulator. Preferably, the action of the external magnetic field described above causes the high-frequency magnetic field applying member to operate at a frequency at which the imaginary number part decreases when the real number part of the complex magnetic permeability increases, or at a frequency where the imaginary number part of the magnetic permeability can be ignored. However, in the dependence of the high frequency permeability on the external magnetic field, even if the actions of the real number part and the imaginary number part cancel each other out, operation is possible if either one action is strong.
【００５０】磁界変調部近傍の磁路（２）に関しては、
（請求項２に記載のように、）これを一軸異方性を有す
る磁性体で構成し、その磁化容易軸を高周波磁界に対し
垂直とすれば、高周波領域での磁路（２）の透磁率を高
いものとすることができ、高周波領域の高出力が確保さ
れる。Regarding the magnetic path (2) near the magnetic field modulation section,
If it is made of a magnetic material having uniaxial anisotropy (as described in claim 2) and its easy axis of magnetization is perpendicular to the high frequency magnetic field, the magnetic path (2) in the high frequency region is transparent. The magnetic susceptibility can be made high, and high output in a high frequency region can be secured.
【００５１】また、（請求項３に記載のように、）磁路
（２）を絶縁層により分離された多層構造の強磁性金属
膜とすれば、磁路（２）の高周波透磁率の虚数部を低下
させることに寄与し、渦電流損失等に起因する高周波磁
束検知用部材へ到達する高周波磁束の減衰を防止でき
る。If the magnetic path (2) is a ferromagnetic metal film having a multi-layered structure separated by an insulating layer (as in claim 3), the imaginary number of the high frequency magnetic permeability of the magnetic path (2). It is possible to prevent the attenuation of the high frequency magnetic flux that reaches the high frequency magnetic flux detecting member due to the eddy current loss and the like, which contributes to the reduction of the portion.
【００５２】さらに、（請求項４に記載のように、）高
周波磁界印加手段が磁路（２）に巻回されたコイルを有
する場合にはこれに高周波電流を印加することにより容
易に高周波磁界が印加され、微小な磁路構造が実現さ
れ、超高密度磁気記録媒体の読み取りに適すると共に、
高周波磁界印加用部材の形成コストの低下に寄与する。
また、（請求項５に記載のように、）永久磁石をバイア
ス磁界印加用部材として使用する場合には形成プロセス
が簡易となり、低コスト化が実現される。Further, when the high-frequency magnetic field applying means has a coil wound around the magnetic path (2) (as in claim 4), the high-frequency magnetic field can be easily applied by applying a high-frequency current to the coil. Is applied to realize a minute magnetic path structure, which is suitable for reading ultra-high density magnetic recording media, and
This contributes to a reduction in the cost of forming the member for applying a high frequency magnetic field.
Further, when the permanent magnet is used as the bias magnetic field applying member (as described in claim 5), the forming process is simplified and the cost is reduced.
【００５３】バイアス磁界の強度を好ましい値に維持す
ることは本発明において重要であるが、（請求項６に記
載のように、）直流電流が通電されるコイルをバイアス
磁界印加用部材として使用する場合にはバイアス磁界の
制御性と経時特性が特に良く、精度が向上する。そし
て、バイアス磁界の値を変化させることが容易で、検知
磁界のフルスケールを容易に変更できる利点を有し、検
知磁界の領域の拡大に寄与する。なお、高周波磁界印加
用部材がコイルである場合には、このコイルと別体のコ
イルをバイアス磁界印加用に形成しても良いが、高周波
磁界印加用コイルに高周波電界と直流電界を重畳してバ
イアス磁界を得ても良い。It is important in the present invention to maintain the strength of the bias magnetic field at a preferable value, but a coil to which a direct current is applied (as described in claim 6) is used as the bias magnetic field applying member. In this case, the controllability of the bias magnetic field and the characteristics over time are particularly good, and the accuracy is improved. Further, the value of the bias magnetic field can be easily changed, and the full scale of the detection magnetic field can be easily changed, which contributes to the expansion of the region of the detection magnetic field. When the high-frequency magnetic field applying member is a coil, a coil separate from this coil may be formed for applying the bias magnetic field, but the high-frequency magnetic field applying coil is superposed with the high-frequency electric field and the DC electric field. A bias magnetic field may be obtained.
【００５４】以上の説明において、バイアス磁界の印加
方法は上記に限定されず、バイアス磁界が磁路（２）に
平行な成分を有する限り任意であるが、特に、（請求項
７に記載のように、）磁界変調部近傍に接続されるバイ
アス磁界用の磁路（３）を設置した構成の磁気ヘッドも
可能である。この磁気ヘッドはバイアス磁界が作用する
領域を磁路（２）の一部に限定するため、バイアス磁界
による磁路（２）の高周波特性の劣化を抑制できる。従
って、特に強いバイアス磁界を印加する場合に有効であ
る。In the above description, the method of applying the bias magnetic field is not limited to the above, and any method may be used as long as the bias magnetic field has a component parallel to the magnetic path (2). In addition, a magnetic head having a configuration in which a magnetic path (3) for a bias magnetic field connected in the vicinity of the magnetic field modulator is installed is also possible. Since this magnetic head limits the region on which the bias magnetic field acts to a part of the magnetic path (2), it is possible to suppress deterioration of the high frequency characteristics of the magnetic path (2) due to the bias magnetic field. Therefore, it is effective when a particularly strong bias magnetic field is applied.
【００５５】なお、第３の磁路を設置しない場合になお
強い磁界を磁界変調部に印加する場合は、（請求項８に
記載のように、）磁路（２）に巻回される直流磁界発生
用のコイルを使用しても良い。これにより高周波磁界印
加用コイルとバイアス磁界印加用コイルとを同一の形成
プロセスで形成することが可能で、形成コスト低下に寄
与する。尚、この場合には磁路（２）の磁界変調部近傍
以外の断面積を特に大きくすることが重要である。When a strong magnetic field is applied to the magnetic field modulating section when the third magnetic path is not installed, the direct current wound around the magnetic path (2) (as described in claim 8). A coil for generating a magnetic field may be used. As a result, the high frequency magnetic field applying coil and the bias magnetic field applying coil can be formed in the same forming process, which contributes to a reduction in forming cost. In this case, it is important to increase the cross-sectional area of the magnetic path (2) other than near the magnetic field modulation portion.
【００５６】磁路（２）の高周波透磁率の虚数部分が大
きな周波数領域で高周波磁界を印加する場合には、この
影響を考慮した部材の配置が好ましい。即ち、高周波磁
界印加専用のコイルとバイアス磁界印加専用のコイルと
を使用する磁気ヘッドでは、（請求項９に記載のよう
に、）磁界変調部と高周波磁界印加用のコイルとの間の
磁路長の最短距離が、磁界変調部と直流バイアス印加用
のコイルとの間の磁路長の最短距離より小さくすること
が好ましい。When a high-frequency magnetic field is applied in a frequency region where the imaginary part of the high-frequency magnetic permeability of the magnetic path (2) is large, it is preferable to arrange the members in consideration of this influence. That is, in the magnetic head using the coil dedicated to applying the high-frequency magnetic field and the coil dedicated to applying the bias magnetic field, the magnetic path between the magnetic field modulator and the coil for applying the high-frequency magnetic field (as described in claim 9). It is preferable that the shortest short distance is smaller than the shortest magnetic path length between the magnetic field modulator and the DC bias applying coil.
【００５７】磁界変調部における、磁路（１）と磁路
（２）との角度関係であるが、（請求項１０に記載のよ
うに、）これを直交させれば、磁路（２）に浸入する検
知磁界は微小なものとなり、高周波磁界の検知を容易に
行なうことができる。また、高周波磁界やバイアス磁界
の磁極への到達も微小なものとなり、磁気記録媒体の読
み取り用の磁気ヘッドとして用いる場合の磁気記録媒体
の劣化を防止できると共に、検知磁界の変動に起因する
ノイズの低減に寄与し、Ｓ／Ｎ比が向上する。Regarding the angular relationship between the magnetic path (1) and the magnetic path (2) in the magnetic field modulation section, if these are orthogonalized (as in claim 10), the magnetic path (2) is obtained. The detection magnetic field penetrating into the space becomes very small, and the high-frequency magnetic field can be easily detected. Further, the arrival of the high-frequency magnetic field and the bias magnetic field at the magnetic pole is also very small, so that the deterioration of the magnetic recording medium when used as a magnetic head for reading the magnetic recording medium can be prevented, and the noise caused by the fluctuation of the detection magnetic field can be prevented. It contributes to the reduction and improves the S / N ratio.
【００５８】上述したように、磁界変調部の磁化の向き
を、外部磁界が０の状態で高周波磁界に対し非平行とす
れば、磁化の向きの弁別が可能であるが、請求項１１に
記載の発明がこれに該当する。特に、請求項１２に記載
のように、結晶磁気異方性、誘導磁気異方性または形状
磁気異方性、あるいはこれらの組合せなどの作用により
磁界変調部を構成した場合には、簡易な素子構造とな
る。また、（請求項１３に記載のように、）バイアス磁
界印加手段が磁路（１）に巻回されたコイルを有する場
合にはバイアス磁界の角度の調整が容易となり、また、
これは精度の向上に寄与する。As described above, if the magnetization direction of the magnetic field modulation section is made non-parallel to the high frequency magnetic field when the external magnetic field is 0, the magnetization direction can be discriminated. The invention of corresponds to this. Particularly, in the case where the magnetic field modulator is configured by the action of crystal magnetic anisotropy, induced magnetic anisotropy or shape magnetic anisotropy, or a combination thereof as described in claim 12, a simple element It becomes a structure. Further, when the bias magnetic field applying means has a coil wound around the magnetic path (1) (as in claim 13), the angle of the bias magnetic field can be easily adjusted, and
This contributes to improvement in accuracy.
【００５９】本発明による磁気ヘッドを、磁気記録媒体
からの磁界検出用に使用する場合、高周波磁束の磁極へ
の到達は好ましくないが、（請求項１４に記載のよう
に、）磁路（１）の強磁性共鳴周波数を、磁界変調部の
それより低くすることにより、高周波磁束の磁極への到
達を抑制することができ、磁気記録媒体の磁気情報の劣
化を防止できる。そして、（請求項１５に記載のよう
に、）高周波磁界印加用部材及び磁路（２）の周囲に高
透磁率導電体からなるシールド手段を配備すれば、電磁
ノイズの発生、及び、電磁ノイズによる誤作動を防止で
きる。When the magnetic head according to the present invention is used for detecting a magnetic field from a magnetic recording medium, it is not preferable that the high frequency magnetic flux reaches the magnetic pole, but the magnetic path (1) is used. By setting the ferromagnetic resonance frequency of (1) lower than that of the magnetic field modulator, it is possible to prevent the high-frequency magnetic flux from reaching the magnetic pole and prevent the deterioration of the magnetic information of the magnetic recording medium. Then, by disposing a shield means made of a high-permeability conductor around the high-frequency magnetic field applying member and the magnetic path (2) (as in claim 15), electromagnetic noise is generated and electromagnetic noise is generated. It is possible to prevent malfunction due to.
【００６０】[0060]
【実施例】以下、本発明による磁気ヘッドの実施例を図
面を参照して説明する。図１は、本発明による磁気ヘッ
ドの構造を示す図であって、（ａ）は磁気ヘッドの平面
図、（ｂ）は（ａ）に示す磁気ヘッドのＡ−Ａ’線断面
図である。図１に示すように、基板１０上に下部磁極３
ａを有する磁路４、ギャップ層２、上部電極３ｂを有す
る磁路５が積層されている。磁路４と磁路５とは磁気的
に接続され、これらは全体として磁路（１）１１を構成
している。この磁路（１）１１には検知磁界が導入され
る。本実施例の磁極の構造は面内磁気記録媒体に対応す
るもので、検知対象の磁界は、磁気記録媒体に起因する
磁界である。Embodiments of the magnetic head according to the present invention will be described below with reference to the drawings. 1A and 1B are views showing the structure of a magnetic head according to the present invention, wherein FIG. 1A is a plan view of the magnetic head, and FIG. 1B is a sectional view taken along the line AA ′ of the magnetic head shown in FIG. As shown in FIG. 1, the lower magnetic pole 3 is formed on the substrate 10.
The magnetic path 4 having a, the gap layer 2, and the magnetic path 5 having the upper electrode 3b are laminated. The magnetic path 4 and the magnetic path 5 are magnetically connected, and these constitute the magnetic path (1) 11 as a whole. A detection magnetic field is introduced into the magnetic path (1) 11. The structure of the magnetic pole of this embodiment corresponds to the in-plane magnetic recording medium, and the magnetic field to be detected is the magnetic field originating from the magnetic recording medium.
【００６１】基板１０上に磁路（２）１２があり、磁路
（１）１１の下部磁極側の磁路４と交差している。この
交差部に磁界変調部１３がある。本実施例では、磁界変
調部１３を構成する磁性体はパーマロイ、磁路（２）１
２を構成する磁性体はＦｅ−Ｎ、磁路（１）１１を構成
する磁性体はセンダストである。Ｆｅ−Ｎはパーマロイ
の約３倍の飽和磁化を有する。磁界変調部１３の磁路
（１）１１に垂直な面での断面積は、検知磁束の量に応
じ適切に設定され、磁界変調部１３の磁路（１）１１に
沿う方向の長さは、検知磁界の起磁力に適合するように
設計される。A magnetic path (2) 12 is provided on the substrate 10 and intersects with the magnetic path 4 on the lower magnetic pole side of the magnetic path (1) 11. The magnetic field modulator 13 is located at this intersection. In this embodiment, the magnetic substance forming the magnetic field modulator 13 is permalloy, and the magnetic path (2) 1
The magnetic substance forming 2 is Fe-N, and the magnetic substance forming magnetic path (1) 11 is sendust. Fe-N has a saturation magnetization about three times that of Permalloy. The cross-sectional area of the magnetic field modulation unit 13 in a plane perpendicular to the magnetic path (1) 11 is appropriately set according to the amount of the detected magnetic flux, and the length of the magnetic field modulation unit 13 in the direction along the magnetic path (1) 11 is , Is designed to match the magnetomotive force of the detection magnetic field.
【００６２】本実施例の磁路（２）１２は閉磁路構造で
ある。磁路（２）１２にはコイル２１が巻回されてお
り、図示されない高周波電源に接続される。本実施例で
は、高周波磁界印加用部材２０は高周波電源とコイル２
１とで構成される。なお、このコイル２１は絶縁層２２
を有している。高周波磁界の周波数は、検知磁界の信号
周波数領域を上回る周波数であって、磁路（２）１２の
強磁性共鳴周波数未満の領域に有る。また、高周波磁束
検知用部材３０は高周波磁束検知用コイル３１で構成さ
れ、高周波磁束検知用コイル３１は図示されない高周波
電界検知手段に接続される。The magnetic circuit (2) 12 of this embodiment has a closed magnetic circuit structure. A coil 21 is wound around the magnetic path (2) 12 and is connected to a high frequency power source (not shown). In this embodiment, the high-frequency magnetic field applying member 20 includes a high-frequency power source and a coil 2.
1 and. The coil 21 has an insulating layer 22.
have. The frequency of the high-frequency magnetic field is higher than the signal frequency range of the detection magnetic field, and is in the range lower than the ferromagnetic resonance frequency of the magnetic path (2) 12. Further, the high frequency magnetic flux detecting member 30 is composed of a high frequency magnetic flux detecting coil 31, and the high frequency magnetic flux detecting coil 31 is connected to a high frequency electric field detecting means (not shown).
【００６３】磁路（２）１２からの高周波磁束の漏洩、
及び、磁路（２）１２の透磁率の虚数部分、即ち高周波
損失による検知磁束の減衰による悪影響を避けるため、
高周波磁界印加用部材２０と磁界変調部１３との間の距
離、及び、高周波磁束検知用部材３０と磁界変調部１３
との間の距離は、小さくすることが重要である。また、
磁路（２）１２の磁路長も可能な範囲で短くし、磁界変
調部近傍以外の断面積も、適宜大きく設定する。Leakage of high frequency magnetic flux from the magnetic path (2) 12,
Also, in order to avoid an adverse effect due to the attenuation of the detected magnetic flux due to the imaginary part of the magnetic permeability of the magnetic path (2) 12, that is, the high frequency loss,
The distance between the high-frequency magnetic field applying member 20 and the magnetic field modulating unit 13, and the high-frequency magnetic flux detecting member 30 and the magnetic field modulating unit 13
It is important that the distance between and is small. Also,
The magnetic path length of the magnetic path (2) 12 is shortened as much as possible, and the cross-sectional area other than the vicinity of the magnetic field modulation portion is appropriately set large.
【００６４】さらに、磁路（２）１２にはコイル４１が
巻回されており、図示されない直流電源に接続され、バ
イアス磁界印加部材４０を構成している。このコイル４
１に直流電流を流すことにより直流磁界が磁路（２）１
２に印加され、磁路（２）１２を介してバイアス磁界が
磁界変調部１３へ印加される。なお、バイアス磁界印加
用コイルと高周波磁界印加用コイルとは必ずしも別体で
ある必要はなく、バイアス磁界印加用兼高周波磁界印加
用コイルに高周波電流と直流電流を重畳して流す構成と
してもよい。また、バイアス磁界印加用部材には、単数
または複数の永久磁石を用いることもできる。また、図
示しないが、磁路（２）１２とは別に、磁界変調部１３
の近傍にバイアス磁界印加用の第三の磁路を設けても良
い。このバイアス磁界の作用により磁界変調部１３の磁
性体の磁区構造は単磁区に近いものとなり、本実施例で
は、その磁化はバイアス磁界及び高周波磁界に概ね平行
である。このため、高周波磁束検知用部材３０に検知さ
れる高周波磁束は、Ｈを磁極に対応する方向の検知磁界
として、概ね｜Ｈ｜の関数となる。Further, a coil 41 is wound around the magnetic path (2) 12 and is connected to a DC power source (not shown) to form a bias magnetic field applying member 40. This coil 4
1 by applying a direct current to the magnetic field (2) 1
2, and the bias magnetic field is applied to the magnetic field modulator 13 via the magnetic path (2) 12. The bias magnetic field applying coil and the high frequency magnetic field applying coil do not necessarily have to be separate bodies, and a high frequency current and a direct current may be superposed on the bias magnetic field applying and high frequency magnetic field applying coil. Further, a single or a plurality of permanent magnets can be used as the bias magnetic field applying member. Although not shown, the magnetic field modulation unit 13 is provided separately from the magnetic path (2) 12.
A third magnetic path for applying a bias magnetic field may be provided in the vicinity of. Due to the action of this bias magnetic field, the magnetic domain structure of the magnetic substance of the magnetic field modulation section 13 becomes close to a single magnetic domain, and in this embodiment, its magnetization is substantially parallel to the bias magnetic field and the high frequency magnetic field. Therefore, the high-frequency magnetic flux detected by the high-frequency magnetic flux detecting member 30 is approximately a function of | H |, where H is the detected magnetic field in the direction corresponding to the magnetic pole.
【００６５】高周波磁界印加用部材２０の駆動周波数
は、磁路（２）１２の強磁性共鳴周波数未満の範囲に存
在するが、特に、磁路（１）１１の強磁性共鳴周波数を
磁路（２）１２の強磁性共鳴周波数未満とし、かつ、高
周波磁界印加用部材２０の駆動周波数をこれを上回る周
波数とすれば、磁極に到達する高周波磁界の強度は微弱
なものとなる。The driving frequency of the high-frequency magnetic field applying member 20 exists in the range lower than the ferromagnetic resonance frequency of the magnetic path (2) 12, and particularly, the ferromagnetic resonance frequency of the magnetic path (1) 11 is set to the magnetic path ( 2) If the ferromagnetic resonance frequency of 12 is set and the driving frequency of the high-frequency magnetic field applying member 20 is set to a frequency higher than this, the intensity of the high-frequency magnetic field reaching the magnetic pole will be weak.
【００６６】次に、図２は本発明の第２の実施例による
磁気ヘッドの概略構成を示す平面図である。図２で、磁
化の符号を弁別するために、磁路（１）１１にバイアス
磁界印加用のコイル１６が付加されている。このバイア
ス磁界印加用のコイル１６は図示されない直流電源に接
続される。これと磁路（２）１２に設置されるバイアス
磁界印加用部材４０による磁界とが重ね合わされ、外部
磁界が０の状態での磁界変調部１３の磁化の向きを高周
波磁界に対し、制御性良く、一定の角度で傾けることが
できる。このため、所定の最大検知磁界Ｈ0 に対する透
磁率を最小とする透磁率の検知磁界依存性を得ることが
できる。そして、−Ｈ0＜Ｈ＜Ｈ0の範囲の検知磁界Ｈに
対し、磁界変調部の透磁率と検知磁界との対応関係は
１：１となるため、磁界を一意に検知することができ、
磁化の向きの判定が可能となる。なお、磁界変調部の単
磁区構造を容易に得るため、公知の反強磁性下地層を磁
界変調部の磁性層の下地層として使用しても良い。Next, FIG. 2 is a plan view showing a schematic structure of a magnetic head according to a second embodiment of the present invention. In FIG. 2, a coil 16 for applying a bias magnetic field is added to the magnetic path (1) 11 in order to discriminate the sign of the magnetization. The coil 16 for applying the bias magnetic field is connected to a DC power source (not shown). This and the magnetic field by the bias magnetic field applying member 40 installed in the magnetic path (2) 12 are superposed, and the magnetization direction of the magnetic field modulation unit 13 when the external magnetic field is 0 is controlled with respect to the high frequency magnetic field with good controllability. , Can be tilted at a certain angle. Therefore, it is possible to obtain the dependency of the magnetic permeability on the detection magnetic field that minimizes the magnetic permeability with respect to the predetermined maximum detection magnetic field H 0 . Then, for the detection magnetic field H in the range of −H 0 <H <H 0 , the correspondence between the magnetic permeability of the magnetic field modulator and the detection magnetic field is 1: 1, so that the magnetic field can be uniquely detected.
It is possible to determine the direction of magnetization. Note that a known antiferromagnetic underlayer may be used as the underlayer of the magnetic layer of the magnetic field modulation section in order to easily obtain the single domain structure of the magnetic field modulation section.
【００６７】また、磁化の方向を弁別する第３の実施例
として、磁界変調部に一軸異方性を誘導し、該磁界変調
部の磁性体の磁化容易軸を高周波磁界に対し非平行と
し、かつ、磁化困難軸を高周波磁界に対し非平行とした
ものがある。磁界変調部は薄膜であるが、その面内の磁
化容易軸はバイアス磁界に対し、非平行であるため、高
周波磁界と磁化は非平行となる。ここで、磁化困難軸も
バイアス磁界に非平行であるため、磁区構造は第２の実
施例と同様のものとなり、磁化の方向を弁別できる。As a third embodiment for discriminating the direction of magnetization, uniaxial anisotropy is induced in the magnetic field modulation section, and the easy axis of magnetization of the magnetic material of the magnetic field modulation section is made non-parallel to the high frequency magnetic field. In addition, there is one in which the axis of hard magnetization is not parallel to the high frequency magnetic field. Although the magnetic field modulator is a thin film, the easy axis of magnetization in the plane is not parallel to the bias magnetic field, so the high frequency magnetic field and the magnetization are not parallel. Here, since the hard magnetization axis is also non-parallel to the bias magnetic field, the magnetic domain structure is similar to that of the second embodiment, and the magnetization direction can be discriminated.
【００６８】[0068]
【発明の効果】以上説明したように、本発明の磁気ヘッ
ドは、上記のごとく構成したことにより以下のような効
果を得ることができた。すなわち、請求項１による磁気
ヘッドでは、超高密度磁気記録媒体等の微細領域の磁界
にも対応可能な、良好なＳ／Ｎ比と高感度を兼ね備えた
（再生用磁気ヘッド、あるいはメカ系の位置センサ用の
磁気ヘッド等への応用が可能な）磁気ヘッドを実現でき
るという効果を得られた。As described above, the magnetic head of the present invention has the following effects by being configured as described above. That is, the magnetic head according to claim 1 has both a good S / N ratio and high sensitivity that can cope with a magnetic field in a fine region of an ultra-high density magnetic recording medium (reproducing magnetic head or mechanical system). The effect of being able to realize a magnetic head (which can be applied to a magnetic head for a position sensor or the like) was obtained.
【００６９】請求項２による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
高周波領域において高い出力を有する磁気ヘッドが実現
できるという効果が得られた。In the magnetic head according to claim 2, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultra high density magnetic recording medium,
The effect that a magnetic head having a high output in a high frequency region can be realized was obtained.
【００７０】請求項３による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
高周波領域の渦電流損失に起因する検出出力低下を抑制
するという効果が得られた。In the magnetic head according to claim 3, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultra high density magnetic recording medium,
The effect of suppressing the decrease in the detection output due to the eddy current loss in the high frequency region was obtained.
【００７１】請求項４による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
高周波磁界印加用部材の形成コストを低下させるという
効果が得られた。In the magnetic head according to claim 4, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultra high density magnetic recording medium,
The effect of reducing the formation cost of the high-frequency magnetic field applying member was obtained.
【００７２】請求項５による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
バイアス磁界印加部材の形成コストを低下させるという
効果が得られた。In the magnetic head according to claim 5, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultra high density magnetic recording medium,
The effect of reducing the formation cost of the bias magnetic field applying member was obtained.
【００７３】請求項６による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
検知磁界の精度の向上、検知磁界の測定範囲の拡張が実
現されるという効果が得られた。In the magnetic head according to the sixth aspect, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultra high density magnetic recording medium,
The effect that the accuracy of the detection magnetic field is improved and the measurement range of the detection magnetic field is expanded is obtained.
【００７４】請求項７による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
バイアス磁界に起因する高周波特性の劣化を特に良好に
抑制するという効果が得られた。According to a seventh aspect of the present invention, there is provided a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine area such as an ultrahigh density magnetic recording medium.
The effect of suppressing particularly the deterioration of the high frequency characteristics due to the bias magnetic field was obtained.
【００７５】請求項８による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
形成コストの低下に寄与するという効果が得られた。In the magnetic head according to the present invention, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultrahigh density magnetic recording medium,
The effect of contributing to the reduction of the formation cost was obtained.
【００７６】請求項９による磁気ヘッドでは、超高密度
磁気記録媒体等の微細領域の磁界にも対応可能な、良好
なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおいて、
高周波磁界の漏洩に起因する出力の低下を抑制するとい
う効果が得られた。In the magnetic head according to claim 9, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultrahigh density magnetic recording medium,
The effect of suppressing the decrease in output due to the leakage of the high frequency magnetic field was obtained.
【００７７】請求項１０による磁気ヘッドでは、超高密
度磁気記録媒体等の微細領域の磁界にも対応可能な、良
好なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおい
て、磁気記録媒体への悪影響を抑制し、さらに良好なＳ
／Ｎ比が得られるという効果が得られた。According to a tenth aspect of the present invention, there is provided a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultrahigh density magnetic recording medium. Suppresses adverse effects and further improves S
The effect of obtaining the / N ratio was obtained.
【００７８】請求項１１による磁気ヘッドでは、超高密
度磁気記録媒体等の微細領域の磁界にも対応可能な、良
好なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおい
て、検知磁界の向きの弁別が可能となるという効果が得
られた。In the magnetic head according to the eleventh aspect, in the magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine area such as an ultrahigh density magnetic recording medium, The effect is that discrimination is possible.
【００７９】請求項１２による磁気ヘッドでは、超高密
度磁気記録媒体等の微細領域の磁界にも対応可能な、良
好なＳ／Ｎ比と高感度を兼ね備え、さらに、検知磁界の
向きの弁別が可能な磁気ヘッドにおいて、形成コストの
低下が可能となるという効果が得られた。The magnetic head according to claim 12 has a good S / N ratio and high sensitivity capable of coping with a magnetic field in a fine region such as an ultra-high density magnetic recording medium, and further discriminates the direction of the detected magnetic field. In the possible magnetic head, the effect that the formation cost can be reduced was obtained.
【００８０】請求項１３による磁気ヘッドでは、超高密
度磁気記録媒体等の微細領域の磁界にも対応可能な、良
好なＳ／Ｎ比と高感度を兼ね備え、さらに、検知磁界の
向きの弁別が可能な磁気ヘッドにおいて、検知磁界の精
度が向上するという効果が得られた。In the magnetic head according to the thirteenth aspect, the magnetic head has both a good S / N ratio and high sensitivity capable of coping with a magnetic field in a fine region such as an ultra-high density magnetic recording medium, and further discriminating the direction of the detected magnetic field. In the possible magnetic head, the effect of improving the accuracy of the detection magnetic field was obtained.
【００８１】請求項１４による磁気ヘッドでは、超高密
度磁気記録媒体等の微細領域の磁界にも対応可能な、良
好なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおい
て、磁気情報の読み取りに伴う媒体磁化の減衰を抑制で
きるという効果が得られた。In the magnetic head according to the fourteenth aspect, a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine region such as an ultrahigh density magnetic recording medium, can read magnetic information. The effect that the attenuation of the accompanying medium magnetization can be suppressed was obtained.
【００８２】請求項１５による磁気ヘッドでは、超高密
度磁気記録媒体等の微細領域の磁界にも対応可能な、良
好なＳ／Ｎ比と高感度を兼ね備えた磁気ヘッドにおい
て、電磁ノイズの発生防止、及び、外部電磁ノイズによ
る誤作動の防止ができるという効果が得られ、さらに、
複数のヘッドを近接配置可能な特性を有するものとする
ことが可能となる効果が得られた。In the magnetic head according to the fifteenth aspect, electromagnetic noise is prevented in a magnetic head having a good S / N ratio and high sensitivity, which can cope with a magnetic field in a fine area such as an ultrahigh density magnetic recording medium. , And the effect of preventing malfunction due to external electromagnetic noise can be obtained.
The effect that the plurality of heads can be arranged close to each other has been obtained.
【図１】本発明による磁気ヘッドの一実施例を示す図で
あって、（ａ）は磁気ヘッドの平面図、（ｂ）は（ａ）
に示す磁気ヘッドのＡ−Ａ’線断面図である。FIG. 1 is a diagram showing an embodiment of a magnetic head according to the present invention, in which (a) is a plan view of the magnetic head and (b) is (a).
3 is a cross-sectional view of the magnetic head shown in FIG.
【図２】本発明による磁気ヘッドの別の実施例を示す平
面図である。FIG. 2 is a plan view showing another embodiment of the magnetic head according to the present invention.
【図３】本発明による磁気ヘッドの原理説明図であっ
て、検知磁界Ｈが０の状態で磁界変調部の磁化が磁路
（２）に平行な角度関係となる場合の、磁界変調部近傍
の磁路の主要磁区の構造を示す図である。FIG. 3 is a diagram illustrating the principle of the magnetic head according to the present invention, in the vicinity of the magnetic field modulation section when the detection magnetic field H is 0 and the magnetization of the magnetic field modulation section has an angular relationship parallel to the magnetic path (2). It is a figure which shows the structure of the main magnetic domain of the magnetic path of.
【図４】本発明による磁気ヘッドの原理説明図であっ
て、検知磁界Ｈが作用した状態での磁界変調部近傍の磁
路の主要磁区の構造を示す図である。FIG. 4 is a diagram for explaining the principle of the magnetic head according to the present invention, and is a diagram showing the structure of the main magnetic domain of the magnetic path in the vicinity of the magnetic field modulation section when the detection magnetic field H is applied.
【図５】本発明による磁気ヘッドの原理説明図であっ
て、検知磁界Ｈが０の状態で磁界変調部の磁化が磁路
（２）に対し斜交している場合の磁界変調部近傍の磁路
の主要磁区の構造を示す図である。FIG. 5 is a diagram for explaining the principle of the magnetic head according to the present invention, showing the vicinity of the magnetic field modulation part when the magnetization of the magnetic field modulation part is oblique to the magnetic path (2) when the detection magnetic field H is 0. It is a figure which shows the structure of the main magnetic domain of a magnetic path.
【図６】図５に示す磁化状態の磁界変調部に検知磁界＋
Ｈ0 が重畳された場合の主要磁区の構造を示す図であ
る。6 is a diagram illustrating a detection magnetic field + in a magnetic field modulation unit in a magnetized state shown in FIG.
It is a diagram showing the structure of the main magnetic domain when H 0 is superimposed.
【図７】図５に示す磁化状態の磁界変調部に検知磁界−
Ｈ0 が重畳された場合の主要磁区の構造を示す図であ
る。FIG. 7 shows a detection magnetic field in the magnetic field modulation unit in the magnetization state shown in FIG.
It is a diagram showing the structure of the main magnetic domain when H 0 is superimposed.
【図８】従来技術の一例を示す磁気再生装置の概略構成
図である。FIG. 8 is a schematic configuration diagram of a magnetic reproducing device showing an example of a conventional technique.
【図９】従来技術の一例を示す磁気記録再生装置の概略
構成図である。FIG. 9 is a schematic configuration diagram of a magnetic recording / reproducing apparatus showing an example of a conventional technique.
２：ギャップ層 ３ａ：下部磁極 ３ｂ：上部磁極 ４，５：磁路 １０：基板 １１：磁路（１） １２：磁路（２） １３：磁界変調部 １６：バイアス磁界発生用コイル ２０：高周波磁界印加用部材 ２１：高周波磁界印加用コイル ２２：絶縁層 ３０：高周波磁束検知用部材 ３１：高周波磁束検知用コイル ４０：バイアス磁界印加用部材 ４１：バイアス磁界印加用コイル 2: Gap layer 3a: Lower magnetic pole 3b: Upper magnetic pole 4, 5: Magnetic path 10: Substrate 11: Magnetic path (1) 12: Magnetic path (2) 13: Magnetic field modulator 16: Bias magnetic field generating coil 20: High frequency Magnetic field applying member 21: High frequency magnetic field applying coil 22: Insulating layer 30: High frequency magnetic flux detecting member 31: High frequency magnetic flux detecting coil 40: Bias magnetic field applying member 41: Bias magnetic field applying coil
Claims (15)
磁路（１）と記す）と、高周波磁界が印加される第二の
磁路（以下、磁路（２）と記す）と、該磁路（１）と該
磁路（２）との交差部に存在し、上記検知磁界と上記高
周波磁界が交差する磁界変調部と、該磁路（２）に上記
高周波磁界を印加する高周波磁界印加用部材と、該磁路
（２）に設置される高周波磁束検知用部材とを有し、該
磁界変調部の高周波透磁率の変化を利用することにより
磁界を検知することを特徴とする磁気ヘッドにおいて、 上記磁界変調部を構成する磁性体の飽和磁束密度を該磁
界変調部近傍の上記磁路（２）を構成する磁性体の飽和
磁束密度より低くし、かつ、上記磁界変調部を単磁区と
するためのバイアス磁界印加用部材を有することを特徴
とする磁気ヘッド。1. A first magnetic path (hereinafter, referred to as a magnetic path) into which a detection magnetic field is introduced.
Magnetic path (1)), a second magnetic path to which a high-frequency magnetic field is applied (hereinafter referred to as magnetic path (2)), and the intersection of the magnetic path (1) and the magnetic path (2). Located in the magnetic field, the magnetic field modulation section where the detection magnetic field intersects with the high frequency magnetic field, the high frequency magnetic field applying member for applying the high frequency magnetic field to the magnetic path (2), and the magnetic path (2) are installed. A magnetic head having a high-frequency magnetic flux detecting member, wherein a magnetic field is detected by utilizing a change in high-frequency magnetic permeability of the magnetic field modulating section. A bias magnetic field applying member for making the density lower than the saturation magnetic flux density of the magnetic material forming the magnetic path (2) near the magnetic field modulation section and for making the magnetic field modulation section a single magnetic domain. And a magnetic head.
変調部近傍の磁路（２）を一軸異方性を有する磁性体で
構成し、該一軸異方性を有する磁性体の磁化容易軸を磁
路（２）の高周波磁界に垂直とすることを特徴とする磁
気ヘッド。2. The magnetic head according to claim 1, wherein the magnetic path (2) in the vicinity of the magnetic field modulation portion is made of a magnetic material having uniaxial anisotropy, and the magnetic easy axis of the magnetic material having the uniaxial anisotropy. Is perpendicular to the high frequency magnetic field of the magnetic path (2).
て、磁路（２）を絶縁層により隔てられた多層構造の強
磁性金属膜とすることを特徴とする磁気ヘッド。3. The magnetic head according to claim 1 or 2, wherein the magnetic path (2) is a multi-layered ferromagnetic metal film separated by an insulating layer.
おいて、高周波磁界印加用部材が磁路（２）に巻回され
る高周波磁界印加用コイルを有することを特徴とする磁
気ヘッド。4. A magnetic head according to claim 1, wherein the high frequency magnetic field applying member has a high frequency magnetic field applying coil wound around a magnetic path (2).
ドにおいて、バイアス磁界印加用部材が単数または複数
の永久磁石を有することを特徴とする磁気ヘッド。5. The magnetic head according to claim 1, 2, 3 or 4, wherein the bias magnetic field applying member has one or more permanent magnets.
ヘッドにおいて、バイアス磁界印加用部材が単数または
複数の直流磁界発生用のコイルを有することを特徴とす
る磁気ヘッド。6. The magnetic head according to claim 1, 2, 3, 4 or 5, wherein the bias magnetic field applying member has a single or a plurality of DC magnetic field generating coils.
て、バイアス磁界印加用部材がバイアス磁界印加用の第
三の磁路（以下、磁路（３）と記す）を有することを特
徴とする磁気ヘッド。7. The magnetic head according to claim 5, wherein the bias magnetic field applying member has a third magnetic path for applying the bias magnetic field (hereinafter, referred to as magnetic path (3)). Magnetic head.
アス磁界印加用部材が磁路（２）に巻回される直流磁界
発生用のコイルを有することを特徴とする磁気ヘッド。8. The magnetic head according to claim 6, wherein the bias magnetic field applying member has a coil for generating a DC magnetic field wound around the magnetic path (2).
おいて、磁界変調部と高周波磁界印加用部材との磁路
（２）に沿う磁路長の最短距離が、磁界変調部とバイア
ス磁界印加用部材との磁路（２）に沿う磁路長の最短距
離より小さいことを特徴とする磁気ヘッド。9. The magnetic head according to claim 4, wherein the shortest magnetic path length along the magnetic path (2) between the magnetic field modulating section and the high frequency magnetic field applying member is the magnetic field modulating section and the bias magnetic field. A magnetic head characterized in that the magnetic path length along the magnetic path (2) with the applying member is smaller than the shortest distance.
または９記載の磁気ヘッドにおいて、磁路（１）と磁路
（２）とを磁界変調部において直交させることを特徴と
する磁気ヘッド。10. Claims 1, 2, 3, 4, 5, 6, 7, 8
Alternatively, in the magnetic head described in the paragraph 9, the magnetic path (1) and the magnetic path (2) are made orthogonal to each other in the magnetic field modulation section.
８，９または１０記載の磁気ヘッドにおいて、検知磁界
が０の状態での磁界変調部の磁化の向きを、高周波磁界
の向きに対し非平行とすることを特徴とする磁気ヘッ
ド。11. Claims 1, 2, 3, 4, 5, 6, 7,
8. The magnetic head according to 8, 9, or 10, wherein the direction of magnetization of the magnetic field modulation portion when the detection magnetic field is 0 is not parallel to the direction of the high frequency magnetic field.
結晶磁気異方性、誘導磁気異方性、または形状磁気異方
性、あるいはこれらの組合わせの作用により、磁界変調
部の磁性体の磁化容易軸を高周波磁界に対し非平行と
し、かつ、磁化困難軸を高周波磁界に対し非平行とする
ことを特徴とする磁気ヘッド。12. A magnetic head according to claim 11, wherein:
By the action of crystalline magnetic anisotropy, induced magnetic anisotropy, shape magnetic anisotropy, or a combination thereof, the easy axis of magnetization of the magnetic body of the magnetic field modulation section is made non-parallel to the high-frequency magnetic field, and A magnetic head characterized in that the hard axis is made non-parallel to the high frequency magnetic field.
バイアス磁界印加用部材が磁路（１）に巻回される直流
バイアス磁界発生用のコイルを有することを特徴とする
磁気ヘッド。13. A magnetic head according to claim 11, wherein:
A magnetic head characterized in that the bias magnetic field applying member has a coil for generating a DC bias magnetic field wound around the magnetic path (1).
８，９，１０，１１，１２または１３記載の磁気ヘッド
において、高周波磁界印加用部材の駆動周波数が磁路
（１）の強磁性共鳴周波数を上回ることを特徴とする磁
気ヘッド。14. Claims 1, 2, 3, 4, 5, 6, 7,
The magnetic head according to any one of 8, 9, 10, 11, 12 or 13, wherein the driving frequency of the high frequency magnetic field applying member exceeds the ferromagnetic resonance frequency of the magnetic path (1).
８，９，１０，１１，１２，１３または１４記載の磁気
ヘッドにおいて、高周波磁界印加用部材及び磁路（２）
の周囲に高透磁率導電体からなるシールド手段を配備す
ることを特徴とする磁気ヘッド。15. Claims 1, 2, 3, 4, 5, 6, 7,
In the magnetic head described in 8, 9, 10, 11, 12, 13 or 14, a high frequency magnetic field applying member and a magnetic path (2)
A magnetic head characterized in that a shield means made of a high-permeability conductor is provided around the periphery of the magnetic head.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4833395A JPH08249615A (en) | 1995-03-08 | 1995-03-08 | Magnetic head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4833395A JPH08249615A (en) | 1995-03-08 | 1995-03-08 | Magnetic head |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08249615A true JPH08249615A (en) | 1996-09-27 |
Family
ID=12800494
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4833395A Pending JPH08249615A (en) | 1995-03-08 | 1995-03-08 | Magnetic head |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08249615A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10613120B2 (en) * | 2016-10-31 | 2020-04-07 | Yokogawa Electric Corporation | Current measurement device |
-
1995
- 1995-03-08 JP JP4833395A patent/JPH08249615A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10613120B2 (en) * | 2016-10-31 | 2020-04-07 | Yokogawa Electric Corporation | Current measurement device |
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