JPS59218964A - Magneto-optics device - Google Patents
Magneto-optics deviceInfo
- Publication number
- JPS59218964A JPS59218964A JP58092492A JP9249283A JPS59218964A JP S59218964 A JPS59218964 A JP S59218964A JP 58092492 A JP58092492 A JP 58092492A JP 9249283 A JP9249283 A JP 9249283A JP S59218964 A JPS59218964 A JP S59218964A
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- Prior art keywords
- light
- signal
- effect element
- faraday effect
- light source
- Prior art date
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Abstract
Description
【発明の詳細な説明】
〔発明の属する技術分野〕
本発明は、磁気を加えることによって光の偏波面が回転
するファラデー効果素子を用いて、電流や磁束等を測定
する磁気光学装置に関するものである。[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to a magneto-optical device that measures current, magnetic flux, etc. using a Faraday effect element in which the plane of polarization of light is rotated by applying magnetism. be.
第１図は従来のこの種の装置の一例を示す構成説明図で
ある。ここでは電流測定のための装置を示す。この装置
は、レーザ光源１からの光を偏光板２によって直線偏光
とし、これを例えば重鉛ガラスのようなファラデー効果
素子３に入れる。このファラデー効果素子３から出た出
射光は、入射偏光角と４５°傾いた検光子４を通って受
光器５で検出される。FIG. 1 is a configuration explanatory diagram showing an example of a conventional device of this type. Here, a device for current measurement is shown. This device converts light from a laser light source 1 into linearly polarized light using a polarizing plate 2, and inputs this into a Faraday effect element 3 such as heavy lead glass. The light emitted from the Faraday effect element 3 passes through an analyzer 4 tilted by 45° with respect to the incident polarization angle and is detected by a light receiver 5.
ファラデー効果素子３には、被測定電流工が流れるコイ
ル６が巻いてあり、この電流Ｉによる磁束によって、フ
ァラデー効果素子３内の光の偏波面が回転するもので、
受光器５で受光する光の強度から、電流工の大きさを知
ることができる。A coil 6 through which a current to be measured flows is wound around the Faraday effect element 3, and the magnetic flux caused by this current I rotates the plane of polarization of light within the Faraday effect element 3.
The size of the electrician can be determined from the intensity of the light received by the light receiver 5.
ところで、このような構成の装置は、レーザ光源１のパ
ワーや光伝送路の伝送効率等が変化すると、受光器５で
受光する光強度が変化し、正確な電流測定ができなくな
る。However, in a device having such a configuration, if the power of the laser light source 1 or the transmission efficiency of the optical transmission line changes, the intensity of light received by the light receiver 5 changes, making it impossible to accurately measure current.
ここにおいて、本発明はこのような従来技術における問
題点に鑑みてなされたもので、簡単な構成で・レーザ光
源パワーの変動の影響を受けないこの種の装置を実現し
ようとするものである。The present invention has been made in view of the problems in the prior art, and aims to realize this type of device with a simple configuration and unaffected by fluctuations in laser light source power.
本発明に係る装置は、ファラデー効果素子からの出射光
を２方向に分離するとともに１分離した各党を、偏光方
向が互いに４５°回転させて設置した検光子を介してそ
れぞれ受光し、受光器からの各信号の自乗和の平方根に
関連した信号を基準信号として、いずれか一方の受光器
からの信号を演算処理し、ファラデー効果に与えられる
磁束あるいはコイルに与えられる電流を知るようにした
ものである。The device according to the present invention separates the emitted light from the Faraday effect element into two directions, receives each separated part through an analyzer installed with the polarization direction rotated by 45 degrees, and sends the light from the light receiver. The signal related to the square root of the sum of the squares of each signal is used as a reference signal, and the signal from either receiver is processed to determine the magnetic flux given to the Faraday effect or the current given to the coil. be.
第２図は本発明に係る装置の一例を示す構成ブ１’ツタ
図である。図において、１はレーザ光源。FIG. 2 is a block 1' diagram showing an example of the apparatus according to the present invention. In the figure, 1 is a laser light source.
２はレーザ光源１からの光を直線偏光とする偏光孜、５
はファラデー効果素子で、これ釦は測定丁べき電流■が
流れるコイル６が巻回されている。2 is a polarizer that makes the light from the laser light source 1 linearly polarized; 5
is a Faraday effect element, and this button is wound with a coil 6 through which the current to be measured flows.
７１．７２はハーフミラ−で、ファラデー効果素子３か
ら出射した出射光を２方向に分離する。４１．４２はハ
ーフミラ−７２で２方向に分離した光が入射する検光子
である。71 and 72 are half mirrors that separate the light emitted from the Faraday effect element 3 into two directions. Reference numerals 41 and 42 designate analyzers into which light separated into two directions by a half mirror 72 is incident.
第３図は、各検光子４１．４２及び偏光板２の偏光方向
の関係を示した説明図である。検光子４１の偏向方向は
、偏光板２の偏光方向と同じであり、検光子４１と４２
とは、偏光方向が互いに４５″回転した関係となるよう
に設置されている。FIG. 3 is an explanatory diagram showing the relationship between the polarization directions of each analyzer 41, 42 and the polarizing plate 2. The polarization direction of the analyzer 41 is the same as the polarization direction of the polarizing plate 2, and the polarization direction of the analyzer 41 and 42 is the same as that of the polarizing plate 2.
are arranged so that their polarization directions are rotated 45'' from each other.
第２図に戻り、５１は検光子４１を介して照射される光
を受光する受光素子、５２は検光子４２を介して照射さ
れる光を受光する受光素子、５６はハーフミラ−７１で
反射した光を受光する受光素子、８１．８２は減算回路
、８５．８４．８５はアンプ％ ８６．８７は自乗回路
、８８は加算回路、８９は平方根を求める平方根回路で
ある。自乗回路８６は、７ンプ８３から出力される受光
素子５１からの信号と受光素子５Ｓからの信号の差信号
の自乗を演算する。また、自乗回路８７は。Returning to FIG. 2, 51 is a light receiving element that receives the light irradiated through the analyzer 41, 52 is a light receiving element that receives the light irradiated through the analyzer 42, and 56 is the light that is reflected by the half mirror 71. A light receiving element receives light, 81.82 is a subtraction circuit, 85.84.85 is an amplifier %, 86.87 is a square circuit, 88 is an addition circuit, and 89 is a square root circuit for calculating a square root. The square circuit 86 calculates the square of the difference signal between the signal from the light-receiving element 51 and the signal from the light-receiving element 5S output from the seventh amplifier 83. Moreover, the square circuit 87 is.
アンプ８４かも出力される受光素子５２と受光素子５３
からの信号の差信号の自乗を演算する。なお、ここで、
ハーフミラ−７１、受光素子５３４ アンプ８５及び減
算回路８１．８２は、レーザ光源１の強さ等の変化によ
る影響を除外することを目的として設けられたものであ
り、レーザ光源１に安定なものを使用する場合には、こ
わらは必ずしも必要でない。The light receiving element 52 and the light receiving element 53 output from the amplifier 84
Calculate the square of the difference signal between the signals from. Furthermore, here,
The half mirror 71, the light receiving element 534, the amplifier 85, and the subtracting circuits 81 and 82 are provided for the purpose of excluding the influence of changes in the intensity of the laser light source 1, and are designed to provide a stable laser light source 1. If used, stiffening is not necessary.
９１．９２はＡ／Ｄ変換器、９０はマイクロプロセッサ
のような演算回路、９３は演算回路９０での演算結果を
表示する表示器、９４は比較信号処理回路、９５はアッ
プダウンカウンタである。Ａ／Ｄ変換器９１は、平方根
回路８９からの信号を基準電圧とし、アンプ８３からの
信号Ｅ１をに／Ｉ）変換し、演舞−回路９０は、各Ａ／
Ｄ変換器９１，９２．必要に応じてアップダウンカウン
タ９５からの信号を入力し、所定の演算を行なって電流
又は磁束量を表示器９３に表示させる。Reference numerals 91 and 92 are an A/D converter, 90 is an arithmetic circuit such as a microprocessor, 93 is a display that displays the result of the arithmetic operation in the arithmetic circuit 90, 94 is a comparison signal processing circuit, and 95 is an up/down counter. The A/D converter 91 uses the signal from the square root circuit 89 as a reference voltage and converts the signal E1 from the amplifier 83 into /I).
D converters 91, 92. A signal from the up/down counter 95 is input as necessary, a predetermined calculation is performed, and the current or magnetic flux amount is displayed on the display 93.
この様に構成した装置の動作は次の通りである。The operation of the device configured in this way is as follows.
レーザ光源１からの光は、偏光板２を通って直線偏光と
なり、ファラデー効果素子３に入射する。Light from a laser light source 1 passes through a polarizing plate 2 to become linearly polarized light, and enters a Faraday effect element 3.
ファラデー効果素子３内には、コイル６に流れる電流工
に対応した昏界が生じており、入射したレーザ光の偏波
面はｔ流工に応じて回転する。ファラデー効果素子３を
出た光は、ハーフミラ−７１゜７２でそれぞれ２方向に
分離し、受光素子５３％検光子４１．４２を介して受光
素子５１．５２でそれぞれ電気信号ｅ３＋ ｅｉ＋ ６
２に変換される。Inside the Faraday effect element 3, a coma field corresponding to the electric current flowing through the coil 6 is generated, and the plane of polarization of the incident laser light rotates according to the electric current flowing through the coil 6. The light emitted from the Faraday effect element 3 is separated into two directions by half mirrors 71 and 72, passed through a light receiving element 53% analyzer 41.42, and then converted into electric signals e3+ ei+ 6 by the light receiving element 51.52.
Converted to 2.
ここで、受光素子５１．５２に照射される光は、レーザ
光がファラデー効果素子３内で電流工に応じて回転する
こと、検光子４１と４２とがその偏光面が４５″回転し
た関係で設置されていることから、電流■に応じて互い
に９００位相差をもって正弦波状に変化するものとなる
。Here, the light irradiated onto the light receiving elements 51 and 52 is determined by the fact that the laser beam is rotated in accordance with the electric current within the Faraday effect element 3, and that the plane of polarization of the analyzers 41 and 42 is rotated by 45''. Because they are installed, the current changes sinusoidally with a phase difference of 900 degrees depending on the current.
第４図は、電流Ｉと、各受光素子５１．５２から得られ
る各信号Ｑ１．ｅ２の関係を示した線図である。FIG. 4 shows the current I and each signal Q1.52 obtained from each light receiving element 51.52. It is a diagram showing the relationship of e2.
（８）は、ファラデー素子６に巻回するコイル６の巻数
を少なくした場合であｌハ（ｂｌはコイル６０巻数を多
くした場合で、いずれも、電流工に応じて。(8) is the case where the number of turns of the coil 6 wound around the Faraday element 6 is reduced (1) (bl is the case where the number of turns of the coil 60 is increased, depending on the electrician.
ｅ（、Ｃ７は９０°位相差を保ちつつ正弦波状に変化す
る。e(, C7 changes sinusoidally while maintaining a 90° phase difference.
また、（Ｃ）はコイル６の巻数を更に多くするとともに
、電流Ｉを大きくした場合である。Moreover, (C) is a case where the number of turns of the coil 6 is further increased and the current I is increased.
受光素子５３かもの信号ｅ５は、レーザ光源の強さや、
光伝送路の伝送効率の変化等に対応してお＋７゜減算回
路８１．８２において、各信号ｅ１．・Ｃ２よｌＪ ６
ｓを減することによって、レーザ光源等の変化による影
響を除去する。The signal e5 from the light receiving element 53 depends on the intensity of the laser light source,
In response to changes in transmission efficiency of the optical transmission line, etc., each signal e1.・C2 yo lJ 6
By reducing s, the influence of changes in the laser light source, etc. is removed.
各自乗回路Ｂ６．８７は、アンプ８３．８４からの出力
ＥＩＪ２を自乗し、これが加算回路８８で加算され、そ
の平方根が平方根回路８９で演算される。Each squaring circuit B6.87 squares the output EIJ2 from the amplifier 83.84, which is added in an adder circuit 88, and the square root of the sum is calculated in a square root circuit 89.
いま、アンプ８５の出力Ｂ１ｔアンプ８４の出力Ｅ２を
それぞれ（１）式、（２）式で表わすものと丁れば、平
方根回路８９の出力１Ｂは、（５）式で示すことができ
、電流Ｉによる偏波面の回転角θによらず、常に振幅値
Ａとなる。Now, if the output B1 of the amplifier 85 and the output E2 of the amplifier 84 are expressed by equations (1) and (2), respectively, then the output 1B of the square root circuit 89 can be expressed by equation (5), and the current Regardless of the rotation angle θ of the polarization plane due to I, the amplitude value is always A.
Ｅ＋ ＝Ａ ｓｉｎ Ｉθ（１）・・・叩・曲（１）Ｂ
２ ＝Ａ ｃｏｓ ′θ（Ｉ） ・・
・・・・・・・・・・（２）Ｅｓ＝Ｑτコ１Ｐ−
＝Ａ２５ｉｎ２１７ Ａ２ ｃｏｓ２ ａ＝Ａ
・・・・・・・・・・・・（５）Ａ
／Ｄ変換器９１は、平方根回路８９からの信号Ｅｓを基
準電圧として、アンプ８３の出力Ｂ１をＡ／Ｄ変換する
。これによって、Ａ／Ｄ変換された信号Ｅ１は、振幅値
Ａの影響を受けず、正確に分割されたものとなる。なお
、Ａ／Ｄ変換器９２は、アンプ８５の出力Ｅ１の大きさ
が適当でない場合（感度が十分でない場合）、アンプ８
４の出力Ｅ２を同様にＡ／Ｄ変換するもので、演算回路
９０は、 Ａ／Ｄ変換器９１．９２のうち。E+ =A sin Iθ(1)...Strike/song (1)B
2 = A cos ′θ(I)...
・・・・・・・・・・・・(2) Es=Qτko1P−=A25in217 A2 cos2 a=A
・・・・・・・・・・・・(5)A
The /D converter 91 A/D converts the output B1 of the amplifier 83 using the signal Es from the square root circuit 89 as a reference voltage. As a result, the A/D converted signal E1 is not affected by the amplitude value A and is accurately divided. Note that if the magnitude of the output E1 of the amplifier 85 is not appropriate (if the sensitivity is not sufficient), the A/D converter 92
The arithmetic circuit 90 is one of the A/D converters 91 and 92.
大きさが適当な方のディジタル信号を入力し、偏波面の
回転角ｔｏから電流工の大きさを求めるための所定の演
算を行ない、その演算結果を表示器９３に表示させる。A digital signal having an appropriate magnitude is input, a predetermined calculation is performed to determine the magnitude of the current flow from the rotation angle to of the plane of polarization, and the result of the calculation is displayed on the display 93.
比較、信号処理回路９４は、アンプ８３又はアンプ８４
の出力のいずれかを入力し、この信号の正弦波の山の数
を検出し、アップダウンカウンタ９５にこれを計数させ
る。これらの回路は、コイル６に流れる電流■が大きく
、信号ｅ４．ｅ、；が第４図（Ｃ１に示すように変化１
石場合において使用されるもので、この場合、演算回１
１Ｇ９０は、アップダウンカウンタ９５の計数値をも入
力し、この計数値と偏光角θとから電流Ｉの大きさを演
Ｗ、ｊることとなる。The comparison and signal processing circuit 94 includes the amplifier 83 or the amplifier 84.
, the number of peaks of the sine wave of this signal is detected, and the up/down counter 95 is made to count this. In these circuits, the current ■ flowing through the coil 6 is large, and the signal e4. e, ; is change 1 as shown in Figure 4 (C1).
This is used in the stone case, and in this case, the number of calculations is 1.
The 1G90 also inputs the count value of the up/down counter 95, and calculates the magnitude of the current I from this count value and the polarization angle θ.
なお、人／Ｄ変換器９２．比較信号処理回路９４及びア
ップダウンカウンタ９５は、測足丁べきｔ流■の大きさ
に応じて設ゆられるもので、必ずしも必要としない。Note that the human/D converter 92. The comparison signal processing circuit 94 and the up/down counter 95 are provided depending on the magnitude of the measurement current t, and are not necessarily required.
なお、上記の説明では、ファラデー効果素子５にコイル
６を巻回して電流Ｉｆｔ測定するようにしたものである
が、コイル６をなくシ、ここに磁束を与えるように丁れ
ば、磁束測足な行なうことカーできる。また、ここでは
Ａ／Ｄ変換２）を用（・ディジタル演算を行なうことを
想足したものであるカ；、これらの回路は、Ｅｌ又はＢ
２を平方根回路８９の出力Ｅ８で例えばｂｌ −’ ｓ
ｉｎ Ｏのような割算演算し、振Ｅ８ Ａ
幅Ａを消去するような回路であれば、他の回路構成のも
のであってもよい。In the above explanation, the current Ift is measured by winding the coil 6 around the Faraday effect element 5. However, if the coil 6 is omitted and the magnetic flux is applied here, the magnetic flux can be measured. You can do anything. In addition, here, A/D conversion 2) is used (and is considered to perform digital calculations); these circuits are connected to El or B.
2 at the output E8 of the square root circuit 89, for example, bl −' s
Other circuit configurations may be used as long as the circuit performs a division operation such as in O and erases the amplitude E8 A width A.
以上説明したように、本発明によれば、簡単な構成で、
レーザ光源パワーの変動や、光伝送路の伝送効率の変化
による影響を受けず、高分屏能で電流や磁束等を測足す
ることのできる磁気光学装置が実現できる。As explained above, according to the present invention, with a simple configuration,
It is possible to realize a magneto-optical device that can measure current, magnetic flux, etc. with high resolution without being affected by fluctuations in laser light source power or changes in transmission efficiency of an optical transmission line.
第１図は従来技術の説明図、第２図は本発明に係る装置
の一例を示す構成プＲツタ図、第３図は第２図装置にお
ける偏光板及び各検光子の偏光方向の関係を示した説明
図、第４図は動作を説明するだめの線図である。
１・・・光源、２，４・・・偏光板、５・・・ファラデ
ー効果素子、４１．４２・・・検光子、５，５１〜５５
・・・受光素子、６・・・コイル、７１．７２・・
・ハーフミラ−、８５，８４，８５・・・増幅器、８６
．８７・・・自乗回路％８８・・・加算回路、８９・・
・平方根回路、９１．９２・・・、Ａ／Ｄ変換器、９０
・・・演算回路、９３・・・表示回路、１４・・・比較
回路、９５・・・７ツプタ゛ウンカウンタ。
篤１図Fig. 1 is an explanatory diagram of the prior art, Fig. 2 is a configuration diagram showing an example of the device according to the present invention, and Fig. 3 shows the relationship between the polarizing direction of the polarizing plate and each analyzer in the device shown in Fig. 2. The illustrated diagram, FIG. 4, is a diagram for explaining the operation. 1... Light source, 2, 4... Polarizing plate, 5... Faraday effect element, 41.42... Analyzer, 5, 51-55
... Light receiving element, 6... Coil, 71.72...
・Half mirror, 85, 84, 85...Amplifier, 86
．． 87... Square circuit %88... Addition circuit, 89...
・Square root circuit, 91.92..., A/D converter, 90
... Arithmetic circuit, 93... Display circuit, 14... Comparison circuit, 95... 7-step counter. Atsushi 1 diagram
Claims (3)
偏光板と、直線偏光となった光が入射するファラデー効
果素子と、このファラデー効果素子から出射した光を２
方向に分離する手段と、２方向に分離した各党が入射し
偏光方向が互いに４５＠回転させて設置した２個の検光
子と、各検光子から出射した光を受光する２個の受光素
子と、これら２個の受光素子からの各信号の自乗和の平
方根に関連した信号を得る回路と、前記２個の受光素子
の少なくとも一方からの信号と前記各信号の自乗和の平
方根に関連した信号を入力し所足の演算を行なって前記
ファラデー効果素子内の磁束に関連した信号を得る演算
回路とを具備した磁気光学装置。(1) A light source, a polarizing plate that converts the light from the light source into linearly polarized light, a Faraday effect element into which the linearly polarized light enters, and a Faraday effect element that converts the light emitted from the Faraday effect element into two.
a means for separating light in two directions, two analyzers installed with the polarization directions rotated by 45 degrees each other, and two light-receiving elements receiving light emitted from each analyzer; , a circuit for obtaining a signal related to the square root of the sum of squares of each signal from these two light receiving elements, and a signal related to a signal from at least one of the two light receiving elements and the square root of the sum of squares of each of the signals. and an arithmetic circuit that receives a signal and performs necessary arithmetic operations to obtain a signal related to the magnetic flux within the Faraday effect element.
このコイルに流れる電流に対応した磁束が当該ファラデ
ー効果素子に与えられる特許請求の範囲第１項記載の磁
気光学装置。(2) A coil is wound around the Faraday effect element,
2. The magneto-optical device according to claim 1, wherein a magnetic flux corresponding to the current flowing through the coil is applied to the Faraday effect element.
らの信号を入力しこの信号の正弦波の山の数を計数する
手段を含む特許請求の範囲第１項記載の磁気光学装置。(3) The magneto-optical device according to claim 1, wherein the arithmetic circuit includes means for inputting a signal from at least one of the two light-receiving elements and counting the number of peaks of the sine wave of this signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58092492A JPS59218964A (en) | 1983-05-27 | 1983-05-27 | Magneto-optics device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58092492A JPS59218964A (en) | 1983-05-27 | 1983-05-27 | Magneto-optics device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS59218964A true JPS59218964A (en) | 1984-12-10 |
Family
ID=14055792
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58092492A Pending JPS59218964A (en) | 1983-05-27 | 1983-05-27 | Magneto-optics device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59218964A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61202081U (en) * | 1985-06-08 | 1986-12-18 |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57171271A (en) * | 1981-04-15 | 1982-10-21 | Yokogawa Hokushin Electric Corp | Measuring device for quantity of electricity |
| JPS5938663A (en) * | 1982-08-27 | 1984-03-02 | Hitachi Cable Ltd | Current measuring apparatus using optical fiber |
-
1983
- 1983-05-27 JP JP58092492A patent/JPS59218964A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57171271A (en) * | 1981-04-15 | 1982-10-21 | Yokogawa Hokushin Electric Corp | Measuring device for quantity of electricity |
| JPS5938663A (en) * | 1982-08-27 | 1984-03-02 | Hitachi Cable Ltd | Current measuring apparatus using optical fiber |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61202081U (en) * | 1985-06-08 | 1986-12-18 | ||
| JPH0435811Y2 (en) * | 1985-06-08 | 1992-08-25 |
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