JP3063063B2 - Optical fiber temperature distribution measurement system - Google Patents
Optical fiber temperature distribution measurement systemInfo
- Publication number
- JP3063063B2 JP3063063B2 JP4060435A JP6043592A JP3063063B2 JP 3063063 B2 JP3063063 B2 JP 3063063B2 JP 4060435 A JP4060435 A JP 4060435A JP 6043592 A JP6043592 A JP 6043592A JP 3063063 B2 JP3063063 B2 JP 3063063B2
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- optical fiber
- light
- incident
- measured
- temperature distribution
- Prior art date
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- Measuring Temperature Or Quantity Of Heat (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は光ファイバの温度分布を
光学的に遠隔測定するための光ファイバの温度分布測定
システムに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber temperature distribution measuring system for optically remotely measuring an optical fiber temperature distribution.
【０００２】[0002]
【従来の技術】このような従来技術として、ＯＴＤＲ
（Optical Time Domain Reflectometry）による距離測
定の原理と、ラマン散乱光の検出による温度測定の原理
と組み合わせた装置が知られ、例えば下記の文献 “Intern.Conf.on.Optical Fiber Sensor,SanDiego,PD3
-1〜3-4,(Feb.13 〜14,1985)” に開示されている。2. Description of the Related Art As such a conventional technique, OTDR is known.
An apparatus that combines the principle of distance measurement by (Optical Time Domain Reflectometry) and the principle of temperature measurement by detection of Raman scattered light is known. For example, the following document “Intern. Conf. On. Optical Fiber Sensor, SanDiego, PD3”
-1 to 3-4, (Feb. 13 to 14, 1985) ".
【０００３】これを原理的に説明すると、図７のように
なる。まず、被測定光ファイバ１にパルス光を入射する
と、伝播の過程で後方散乱光が現れ、入射端に戻ってく
る。ここで、ある散乱点までの距離をＬ、パルスの入射
時点から後方散乱光の検出時点までの時間をｔ、被測定
光ファイバ１の屈折率をｎ、被測定光ファイバ１中の光
速をＣo 、被測定光ファイバ１中の光速をＣとすると、 Ｃ＝Ｃo ／ｎ Ｌ＝Ｃ・ｔ／２ となる。したがって、散乱点の位置が定量的に求まる。FIG. 7 illustrates this principle in principle. First, when pulse light enters the optical fiber 1 to be measured, backscattered light appears in the process of propagation and returns to the incident end. Here, the distance to a certain scattering point is L, the time from the point of incidence of the pulse to the point of detection of the backscattered light is t, the refractive index of the measured optical fiber 1 is n, and the speed of light in the measured optical fiber 1 is C. o , assuming that the speed of light in the optical fiber 1 to be measured is C, C = C o / n L = C · t / 2. Therefore, the position of the scattering point can be determined quantitatively.
【０００４】一方、後方散乱光にはレーリ光とストーク
ス光、反ストークス光が含まれ、入射パルス光の波長を
λO とするとレーリ光の波長はλO となり、ストークス
光の波長λS と反ストークス光の波長λASとは、 λS ＝λO ＋Δλ λAS＝λO −Δλ となる（図７（ｂ）参照）。そして、ストークス光強度
ＩS と反ストークス光強度ＩASの比は、被測定光ファイ
バ１中の散乱点の絶対温度Ｔに依存し、ＩAS／ＩS がｅ
ｘｐ（−ｈ・Ｃ・ν／ｋＴ）に比例する関係となる。こ
こで、ｈはプランク定数（Ｊ・Ｓ）、νはラマンシフト
量（ｍ-1）、ｋはボルツマン定数（Ｊ／Ｋ）である。し
たがって、散乱点の温度が定量的に求められる。On the other hand, Rayleigh light and Stokes light in the backscattered light, the anti-Stokes light is included, the wavelength of the Rayleigh light and the wavelength of incident pulse light and lambda O is lambda O, and the wavelength lambda S of Stokes light anti The wavelength λ AS of the Stokes light is λ S = λ O + Δλ λ AS = λ O −Δλ (see FIG. 7B). Then, the ratio of the Stokes light intensity I S and the anti-Stokes light intensity I AS depends on the absolute temperature T of the scattering points in one optical fiber to be measured, I AS / I S is e
xp (-h.C..nu. / kT). Here, h is the Planck constant (J · S), ν is the Raman shift amount (m −1 ), and k is the Boltzmann constant (J / K). Therefore, the temperature of the scattering point can be obtained quantitatively.
【０００５】[0005]
【発明が解決しようとする課題】しかし、上記の原理を
用いてグレーデットインデックス型の光ファイバの温度
分布を測定すると、波形歪みにより測定結果が不正確と
なる欠点があった。すなわち、パルス光の入射条件によ
って光ファイバ中で高次の伝播モードが励起され、これ
が被測定光ファイバ１から漏れ出して入射パルスの波形
を歪ませる。特に、この歪みは被測定光ファイバ１への
入射部、あるいは入射用ファイバと被測定光ファイバ１
の接続部近傍に多く生じる。However, when the temperature distribution of a graded index optical fiber is measured using the above principle, there has been a drawback that the measurement result becomes inaccurate due to waveform distortion. That is, a higher-order propagation mode is excited in the optical fiber by the incident condition of the pulsed light, which leaks out of the measured optical fiber 1 and distorts the waveform of the incident pulse. In particular, this distortion is caused by the incident portion of the optical fiber under test 1 or the incident fiber and the optical fiber 1 under test.
Often occur in the vicinity of the connection part.
【０００６】そこで本発明は、被測定光ファイバの温度
分布を正確に測定することのできる光ファイバの温度分
布測定システムを提供することを目的とする。Accordingly, an object of the present invention is to provide an optical fiber temperature distribution measuring system capable of accurately measuring the temperature distribution of an optical fiber to be measured.
【０００７】[0007]
【課題を解決するための手段】本発明は、被測定光ファ
イバにパルス光を入射し、パルス光の入射タイミングと
後方散乱光の検出タイミングとの時間差から被測定光フ
ァイバの温定点を算出すると共に、後方散乱光に含まれ
るラマン散乱光のうちストークス光と反ストークス光と
の検出強度比から被測定光ファイバの温度を算出する光
ファイバの温度分布測定システムにおいて、被測定ファ
イバへのパルス光の入射部近傍の光ファイバ部分に、当
該光ファイバを屈曲させた屈曲部を設けたことを特徴と
する。According to the present invention, a pulse light is incident on an optical fiber to be measured, and a temperature fixed point of the optical fiber to be measured is calculated from a time difference between an incident timing of the pulse light and a detection timing of the backscattered light. In addition, in the optical fiber temperature distribution measurement system that calculates the temperature of the measured optical fiber from the detected intensity ratio of the Stokes light and the anti-Stokes light of the Raman scattered light included in the backscattered light, the pulse light to the measured fiber is The optical fiber portion in the vicinity of the incident portion is provided with a bent portion obtained by bending the optical fiber.
【０００８】また、一端がパルス光の光源に光結合さ
れ、他端が被測定光ファイバに接続された入射用光ファ
イバを有し、屈曲部は入射用光ファイバを屈曲させて形
成させるようにし、あるいは、入射用光ファイバとの接
続部近傍の被測定光ファイバが屈曲されることにより、
さらに曲部が形成されるようにしてもよい。In addition, one end is optically coupled to a pulsed light source, and the other end has an incident optical fiber connected to the optical fiber to be measured, and the bent portion is formed by bending the incident optical fiber. Or, by bending the measured optical fiber near the connection with the incident optical fiber,
Further, a curved portion may be formed.
【０００９】[0009]
【作用】本発明によれば、入射条件によって被測定用光
ファイバ中に励起された伝播モードのうち、高次のモー
ド光が屈曲部で外部に強制的に排出される。このため、
屈曲部以降の光ファイバ中では外部に漏出しやすい高次
のモード光が少なくなり、波形の歪みが減少される。According to the present invention, among the propagation modes excited in the optical fiber to be measured depending on the incident conditions, the higher-order mode light is forcibly discharged to the outside at the bent portion. For this reason,
In the optical fiber after the bent portion, the amount of higher-order mode light that easily leaks to the outside is reduced, and the distortion of the waveform is reduced.
【００１０】[0010]
【実施例】以下、添付図面により、本発明のいくつかの
実施例を説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the accompanying drawings.
【００１１】図１は第１実施例に係る光ファイバの温度
分布測定システムの構成図である。図示の通り、被測定
光ファイバ１と、これに光結合された測定装置２と、そ
の出力を演算表示する演算表示装置３とを備え、被測定
光ファイバ１の入力部にはマルチモード光ファイバをコ
イル状に巻回した屈曲部１１が設けられている。FIG. 1 is a configuration diagram of an optical fiber temperature distribution measuring system according to a first embodiment. As shown in the figure, an optical fiber 1 to be measured, a measuring device 2 optically coupled thereto, and a calculation display device 3 for calculating and displaying the output thereof are provided. Are provided in a coil shape.
【００１２】測定装置２は半導体レーザ２１を有し、こ
の出力光はビームスプリッタ２２を透過して被測定光フ
ァイバ１に入射される。被測定光ファイバ１からの後方
散乱光はビームスプリッタ２２で光路変換され、波長分
離部２３で波長λS のストークス光と波長λASの反スト
ークス光に分離され、それぞれ光検出器２４S ，２４AS
に入射される。そして、これらの検出出力は、測定装置
２における信号処理部２５を構成する時間差測定部２６
と強度比測定部２７に入力される。The measuring device 2 has a semiconductor laser 21, and the output light is transmitted through a beam splitter 22 and enters the optical fiber 1 to be measured. The backscattered light from the optical fiber 1 to be measured is subjected to optical path conversion by the beam splitter 22 and separated into Stokes light having a wavelength λ S and anti-Stokes light having a wavelength λ AS by a wavelength separation unit 23, and the light detectors 24 S and 24 are respectively provided. AS
Is incident on. These detection outputs are output to a time difference measurement unit 26 that constitutes the signal processing unit 25 in the measurement device 2.
Is input to the intensity ratio measuring unit 27.
【００１３】時間差測定部２６はＬＤ光源駆動部２８か
らのタイミング信号（半導体レーザ２１による入射パル
ス光のタイミング信号）と、後方散乱光の検出タイミン
グ信号の時間差を求める。これにより、前述したＯＴＤ
Ｒの原理にもとづき、測定点までの距離を求めることが
できる。The time difference measuring section 26 calculates a time difference between a timing signal from the LD light source driving section 28 (a timing signal of the incident pulse light from the semiconductor laser 21) and a detection timing signal of the backscattered light. As a result, the above-mentioned OTD
The distance to the measurement point can be obtained based on the principle of R.
【００１４】一方、強度比測定部２７はストークス光と
反ストークス光の強度比を、光検出器２４S ，２４ASの
出力から求める。これにより、前述した測温原理によ
り、被測定光ファイバ１の温度が求まる。On the other hand, the intensity ratio measuring section 27 obtains the intensity ratio between the Stokes light and the anti-Stokes light from the outputs of the photodetectors 24 S and 24 AS . Thus, the temperature of the optical fiber 1 to be measured is determined by the above-described temperature measurement principle.
【００１５】上記の実施例において、被測定光ファイバ
１へのパルス光の入射部には屈曲部１１が設けられてい
るので、高次の伝播モードの光が矢印Ｐのように光ファ
イバ外に漏れ出る。この高次モードの光は、屈曲されて
いない光ファイバにおいても漏れ出しやすく、その距離
は数ｋｍに達する。このため、この数ｋｍの範囲にわた
って入射パルス光の波形が歪んでいたが、本実施例では
屈曲部であらかじめ除去される。このため、屈曲部の後
方の被測定光ファイバ１における光波形の歪みを、高次
モード光の除去により低減させた結果として、測温の精
度が高まる。In the above embodiment, since the bent portion 11 is provided at the incident portion of the pulse light to the optical fiber 1 to be measured, the light of the higher-order propagation mode is emitted out of the optical fiber as shown by the arrow P. Leak out. This high-order mode light easily leaks out even in an unbent optical fiber, and its distance reaches several kilometers. For this reason, the waveform of the incident pulse light was distorted over the range of several km, but in the present embodiment, it is removed in advance at the bent portion. Therefore, as a result of reducing the distortion of the optical waveform in the measured optical fiber 1 behind the bent portion by removing the higher-order mode light, the accuracy of the temperature measurement is improved.
【００１６】本発明は図１の実施例に限定されず、図２
あるいは図３のようになっていてもよい。図２の実施例
では、ビームスプリッタ２２に入射用光ファイバ１２が
光結合され、入射用光ファイバ１２には被測定光ファイ
バ１がコネクタ１３によって接続されている。ここで、
入射用光ファイバ１２には屈曲部が設けられているの
で、ビームプリッタ２２から入射用光ファイバ１２への
パルス光の入射条件により生じる高次モード光は、屈曲
部１１で強制的に外部に排出される。The present invention is not limited to the embodiment of FIG.
Alternatively, it may be as shown in FIG. In the embodiment of FIG. 2, the incident optical fiber 12 is optically coupled to the beam splitter 22, and the measured optical fiber 1 is connected to the incident optical fiber 12 by the connector 13. here,
Since the incident optical fiber 12 is provided with a bent portion, higher-order mode light generated by the incident condition of the pulse light from the beam splitter 22 to the incident optical fiber 12 is forcibly discharged to the outside at the bent portion 11. You.
【００１７】また、図３の実施例では、被測定光ファイ
バ１にコネクタ１３を介して屈曲部１１Ｂを有する入射
用光ファイバ１２が接続され、かつ被測定光ファイバ１
の入射側にも別の屈曲部１１Ａが設けられている。この
場合には、コネクタ１３を介してなされる入射用光ファ
イバ１２から被測定光ファイバ１へのパルス光の入射条
件により生起される高次モード光についても、外部に漏
出させることが可能になる。In the embodiment shown in FIG. 3, the optical fiber 1 to be measured is connected to the optical fiber 1 to be measured via the connector 13 and the incident optical fiber 12 having the bent portion 11B.
Another bent portion 11A is also provided on the incident side of. In this case, even higher-order mode light generated under the conditions of the pulse light incident from the incident optical fiber 12 to the optical fiber under test 1 through the connector 13 can be leaked to the outside. .
【００１８】このように、上記のいずれによっても、波
形歪みの原因となる高次モード光を光ファイバから強制
的に排出できる。この場合、屈曲部１１が被測定光ファ
イバ１への入射パルス光の入射部側に設けられている点
に特徴があり、その数などは特に問題とならない。As described above, in any of the above cases, high-order mode light that causes waveform distortion can be forcibly discharged from the optical fiber. In this case, the characteristic is that the bent portion 11 is provided on the side of the incident portion of the pulse light incident on the optical fiber 1 to be measured, and the number and the like do not particularly matter.
【００１９】屈曲部１１は、例えば図４のように構成さ
れる。図４（ａ）では、光ファイバ１４が１本の芯棒１
５に複数回巻かれて、高次モード光排出用の屈曲部１１
が形成されている。同図（ｂ）では、２本の芯棒１５に
光ファイバ１４が『８』の字状に巻回され、屈曲部１１
が構成されている。この場合、巻回が小径であるほど効
果が高く、巻回数が多いほど効果が高い。但し、光ファ
イバ１４が折れない程度の径であことは当然である。The bent portion 11 is configured, for example, as shown in FIG. In FIG. 4A, the optical fiber 14 is a single core rod 1.
5 is bent a plurality of times to form a bent portion 11 for emitting higher-order mode light.
Are formed. In FIG. 2B, the optical fiber 14 is wound in the shape of “8” around two core rods 15 and the bent portion 11 is formed.
Is configured. In this case, the effect is higher as the winding diameter is smaller, and the effect is higher as the winding number is larger. However, it is natural that the diameter is such that the optical fiber 14 is not broken.
【００２０】次に、具体的な測定例について説明する。
図５は、その構成図である。ラマンＯＴＤＲ装置５１に
はコア径が５０μｍで外径が１２５μｍのクレーデット
インデックス型マルチモード光ファイバ５２ａが接続さ
れ、これには光コネクタ５３によって同構造のマルチモ
ード光ファイバ５２ｂが接続されている。ここで、マル
チモード光ファイバ５２ａは長さ１０ｋｍであり、マル
チモード光ファイバ５２ｂは長さ５ｋｍである。Next, a specific measurement example will be described.
FIG. 5 is a configuration diagram thereof. The Raman OTDR device 51 is connected to a multimode optical fiber 52 a having a core diameter of 50 μm and an outer diameter of 125 μm, and a multimode optical fiber 52 b having the same structure as that of the optical connector 53. Here, the multimode optical fiber 52a has a length of 10 km, and the multimode optical fiber 52b has a length of 5 km.
【００２１】マルチモード光ファイバ５２ａのラマンＯ
ＴＤＲ装置５１側と、マルチモード光ファイバ５２ｂの
光コネクタ５３側には、小径のコイル部が設けられてい
る。すなわち、直径が８ｍｍのガラス棒５４ａ、５４ｂ
のそれぞれに、マルチモード光ファイバ５２ａ、５４ｂ
のそれぞれが４０回づつ巻かれている。これによりラマ
ンＯＴＤＲ装置５１からマルチモード光ファイバ５２ａ
への入射条件と、光コネクタ５３からマルチモード光フ
ァイバ５２ｂへの入射条件とで、光ファイバ中の高次モ
ードが外部に強制的に漏出されている。Raman O of the multimode optical fiber 52a
A small-diameter coil portion is provided on the TDR device 51 side and on the optical connector 53 side of the multi-mode optical fiber 52b. That is, glass rods 54a, 54b having a diameter of 8 mm
, The multimode optical fibers 52a, 54b
Are wound 40 times each. As a result, the multimode optical fiber 52a
The high-order mode in the optical fiber is forcibly leaked to the outside under the condition of incidence on the optical connector 53 and the condition of incidence on the multimode optical fiber 52b from the optical connector 53.
【００２２】一方、上記の測定系において、コイル部を
設けないもの（従来の測定系）を用意した。なお、マル
チモード光ファイバ５２ａ、５２ｂは同様とした。そし
て、上記の実施例および従来例のそれぞれについて、マ
ルチモード光ファイバ５２ａ、５２ｂにを全長にわたっ
て同一温度とし、波長１．３μｍのパルス光を入射し、
ストークス光（波長λｓ＝１．４μｍ）と反ストークス
光（波長λAS＝１．２５μｍ）を測定した。On the other hand, in the above-mentioned measuring system, a system without a coil portion (a conventional measuring system) was prepared. The multimode optical fibers 52a and 52b were the same. Then, in each of the above embodiment and the conventional example, the same temperature is applied to the multimode optical fibers 52a and 52b over the entire length, and pulse light having a wavelength of 1.3 μm is incident thereon.
Stokes light (wavelength λs = 1.4 μm) and anti-Stokes light (wavelength λ AS = 1.25 μm) were measured.
【００２３】測定結果を図６に示す。同図（ａ）のよう
に、従来例では同一温度であるのに入射部側で約２０℃
の温度のずれが観測されたが、本実施例では略一定であ
り、本発明の効果が確認された。FIG. 6 shows the measurement results. As shown in FIG. 2A, in the conventional example, although the temperature is the same, about 20.degree.
Was observed, but in this example, it was substantially constant, and the effect of the present invention was confirmed.
【００２４】[0024]
【発明の効果】以上、詳細に説明した通り、本発明によ
れば、入射条件によって被測定用光ファイバ中に励起さ
れた伝播モードのうち、高次のモード光が屈曲部で外部
に強制的に排出される。このため、屈曲部以降の光ファ
イバ中では外部に漏出しやすい高次のモード光が少なく
なり、波形の歪みが減少される。このため、光ファイバ
の全長にわたって、高精度の温度分布測定ができる。As described above in detail, according to the present invention, among the propagation modes excited in the optical fiber to be measured by the incident condition, the higher-order mode light is forcibly externally applied at the bend. Is discharged. For this reason, in the optical fiber after the bent portion, the number of high-order mode light that easily leaks to the outside is reduced, and the distortion of the waveform is reduced. Therefore, the temperature distribution can be measured with high accuracy over the entire length of the optical fiber.
【図１】第１実施例に係る光ファイバの温度分布測定シ
ステムの構成図。FIG. 1 is a configuration diagram of an optical fiber temperature distribution measurement system according to a first embodiment.
【図２】第２実施例に係る光ファイバの温度分布測定シ
ステムの構成図。FIG. 2 is a configuration diagram of an optical fiber temperature distribution measurement system according to a second embodiment.
【図３】第３実施例に係る光ファイバの温度分布測定シ
ステムの構成図。FIG. 3 is a configuration diagram of an optical fiber temperature distribution measurement system according to a third embodiment.
【図４】屈曲部の具体的な構成図。FIG. 4 is a specific configuration diagram of a bent portion.
【図５】実験系の説明図。FIG. 5 is an explanatory diagram of an experimental system.
【図６】測定結果のグラフ。FIG. 6 is a graph showing measurement results.
【図７】光ファイバの温度分布測定システムの原理説明
図。FIG. 7 is an explanatory view of the principle of an optical fiber temperature distribution measuring system.
１…被測定光ファイバ、２…測定装置、２１…半導体レ
ーザ、２２…ビームスプリッタ、２３…波長分離部、２
４…光検出器、２５…信号処理部、２６…時間差測定
部、２７…強度比測定部、３…演算表示装置、１１…屈
曲部、１２…入射用光ファイバ、１３…コネクタ、１４
…光ファイバ、１５…芯棒、５１…ラマンＯＴＤＲ装
１、５２…マルチモード光ファイバ、５３…光コネク
タ、５４…ガラス棒。DESCRIPTION OF SYMBOLS 1 ... Optical fiber to be measured, 2 ... Measuring device, 21 ... Semiconductor laser, 22 ... Beam splitter, 23 ... Wavelength separation part, 2
DESCRIPTION OF SYMBOLS 4 ... Photodetector, 25 ... Signal processing part, 26 ... Time difference measuring part, 27 ... Intensity ratio measuring part, 3 ... Operation display device, 11 ... Bending part, 12 ... Incident optical fiber, 13 ... Connector, 14
... optical fiber, 15 ... core rod, 51 ... Raman OTDR device 1, 52 ... multimode optical fiber, 53 ... optical connector, 54 ... glass rod.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) G01K 11/12 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) G01K 11/12
Claims (3)
前記パルス光の入射タイミングと後方散乱光の検出タイ
ミングとの時間差から前記被測定光ファイバの測定点を
算出すると共に、前記後方散乱光に含まれるラマン散乱
光のうちストークス光と反ストークス光との検出強度比
から前記被測定光ファイバの温度を算出する光ファイバ
の温度分布測定システムにおいて、 前記パルス光の前記被測定光ファイバへの入射部近傍の
光ファイバ部分に、当該光ファイバを屈曲させた屈曲部
を設けたことを特徴とする光ファイバの温度分布測定シ
ステム。1. A pulse light is incident on an optical fiber to be measured,
The measurement point of the measured optical fiber is calculated from the time difference between the incident timing of the pulse light and the detection timing of the backscattered light, and the Stokes light and the anti-Stokes light of the Raman scattered light included in the backscattered light are calculated. In the optical fiber temperature distribution measuring system for calculating the temperature of the measured optical fiber from the detected intensity ratio, the optical fiber is bent to an optical fiber portion near an incident portion of the pulsed light to the measured optical fiber. An optical fiber temperature distribution measuring system having a bent portion.
れ、他端が前記被測定光ファイバに接続された入射用光
ファイバを有し、前記屈曲部は前記入射用光ファイバを
屈曲させて形成されている請求項１記載の光ファイバの
温度分布測定システム。2. An incident optical fiber having one end optically coupled to the light source of the pulsed light and the other end connected to the optical fiber to be measured, and the bent portion bends the incident optical fiber. The optical fiber temperature distribution measuring system according to claim 1, wherein the optical fiber temperature distribution measuring system is formed.
前記被測定光ファイバが屈曲されることにより、さらに
別の屈曲部が形成されている請求項２記載の光ファイバ
の温度分布測定システム。3. The optical fiber temperature distribution measuring system according to claim 2, wherein another bent portion is formed by bending the measured optical fiber near the connection portion with the incident optical fiber. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4060435A JP3063063B2 (en) | 1992-03-17 | 1992-03-17 | Optical fiber temperature distribution measurement system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4060435A JP3063063B2 (en) | 1992-03-17 | 1992-03-17 | Optical fiber temperature distribution measurement system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05264370A JPH05264370A (en) | 1993-10-12 |
| JP3063063B2 true JP3063063B2 (en) | 2000-07-12 |
Family
ID=13142184
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4060435A Expired - Lifetime JP3063063B2 (en) | 1992-03-17 | 1992-03-17 | Optical fiber temperature distribution measurement system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3063063B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7874725B2 (en) | 2006-09-22 | 2011-01-25 | J-Power Systems Corporation | Optical fiber temperature distribution measuring apparatus, method for measuring optical fiber temperature distribution, and optical fiber temperature distribution measuring system |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2774767B2 (en) * | 1994-03-03 | 1998-07-09 | 株式会社神戸製鋼所 | Optical fiber for temperature distribution measurement |
| EP2787341A4 (en) * | 2011-12-01 | 2015-05-27 | Fujikura Ltd | Method for detecting normal conduction transition of superconducting wire rod |
| JP6206351B2 (en) | 2014-07-15 | 2017-10-04 | 横河電機株式会社 | Optical fiber temperature distribution measuring device |
| JP6413418B2 (en) * | 2014-07-16 | 2018-10-31 | 横河電機株式会社 | Optical fiber temperature distribution measuring device |
| JP6020521B2 (en) | 2014-07-16 | 2016-11-02 | 横河電機株式会社 | Optical fiber temperature distribution measuring device |
| JP2016176744A (en) * | 2015-03-19 | 2016-10-06 | 住友電気工業株式会社 | Optical fiber temperature measuring apparatus |
-
1992
- 1992-03-17 JP JP4060435A patent/JP3063063B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7874725B2 (en) | 2006-09-22 | 2011-01-25 | J-Power Systems Corporation | Optical fiber temperature distribution measuring apparatus, method for measuring optical fiber temperature distribution, and optical fiber temperature distribution measuring system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05264370A (en) | 1993-10-12 |
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