JPH0151136B2 - - Google Patents
Info
- Publication number
- JPH0151136B2 JPH0151136B2 JP57190091A JP19009182A JPH0151136B2 JP H0151136 B2 JPH0151136 B2 JP H0151136B2 JP 57190091 A JP57190091 A JP 57190091A JP 19009182 A JP19009182 A JP 19009182A JP H0151136 B2 JPH0151136 B2 JP H0151136B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- optical fiber
- cladding layer
- break
- optical
- 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.)
- Expired
Links
- 239000013307 optical fiber Substances 0.000 claims description 43
- 238000005253 cladding Methods 0.000 claims description 28
- 230000003287 optical effect Effects 0.000 claims description 16
- 230000005540 biological transmission Effects 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 7
- 230000000644 propagated effect Effects 0.000 claims description 6
- 239000010410 layer Substances 0.000 description 26
- 238000001514 detection method Methods 0.000 description 7
- 230000001902 propagating effect Effects 0.000 description 2
- 239000011253 protective coating Substances 0.000 description 2
- 238000001356 surgical procedure Methods 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000001028 reflection method Methods 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
- G01M11/31—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter and a light receiver being disposed at the same side of a fibre or waveguide end-face, e.g. reflectometers
Landscapes
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
- Testing Of Optical Devices Or Fibers (AREA)
- Light Guides In General And Applications Therefor (AREA)
Description
【発明の詳細な説明】
本発明は、光フアイバの破断を光入射側から検
出する光フアイバの断線検出方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical fiber breakage detection method for detecting a breakage of an optical fiber from the light incident side.
一般に、光伝送系に使用される光フアイバは、
光入射側及び受光側間に介装されており、光フア
イバの使用中に破断等の障害が発生した場合には
光の伝播が遮断若しくは大幅に減衰されて受光側
の出力に異常を来たすので、これにより光フアイ
バの破断を検知することが可能であるが、これを
光入射側で検知することはできず、したがつて、
従来は別途回線を利用して光入射側に断線発生の
信号を伝達する以外に方法がなかつた。 Generally, optical fibers used in optical transmission systems are
It is interposed between the light input side and the light receiving side, and if a failure such as breakage occurs while the optical fiber is in use, the propagation of light will be interrupted or significantly attenuated, causing an abnormality in the output on the light receiving side. , it is possible to detect a break in the optical fiber, but this cannot be detected on the light input side, and therefore,
Conventionally, there was no other way than to use a separate line to transmit a signal indicating the occurrence of a disconnection to the light incident side.
ところで、光フアイバの断線が検出されてから
その破断点を検出する方法としては、光入射側の
光フアイバ端をレーザパルス発振器等の光パルス
発生回路に接続し、光フアイバ内に光パルス信号
を入射し、これが破断点で反射されて反射パルス
が得られる迄の遅延時間を計測することによつて
その破断位置を検出するパルス反射法、また同様
に光フアイバ内に光パルス信号を入射し、光フア
イバの長手方向の各点より反射される後方散乱光
を時間軸上で観測してその減衰曲線から破断点を
検出する後方散乱損失測定法等が種々提案されて
いる。 By the way, as a method to detect the break point after a break in the optical fiber is detected, the end of the optical fiber on the light input side is connected to an optical pulse generation circuit such as a laser pulse oscillator, and an optical pulse signal is transmitted into the optical fiber. The pulse reflection method detects the break position by measuring the delay time until the light enters the optical fiber and is reflected at the break point to obtain a reflected pulse. Various backscatter loss measurement methods have been proposed in which backscattered light reflected from each point in the longitudinal direction of an optical fiber is observed on the time axis and a break point is detected from the attenuation curve.
しかし、これらの検出方法はあくまで光フアイ
バに破断が生じたことが判明した後にその破断点
の位置を検出するものであり、断線の発生自体を
検出するものではない。 However, these detection methods only detect the position of the break point after it is determined that the optical fiber has broken, and do not detect the occurrence of the break itself.
したがつて、上述の如き従来技術によつては、
例えばレーザメス等に使用される医療用光フアイ
バのように受光系を有さざる光伝送系に於ける使
用中の断線発生を自動的に検出することができ
ず、検出するためには光伝送回路を測定用光パル
ス発生回路に切換えなければならないという面倒
があり、光フアイバの断線発生を常時監視するこ
とは不可能であつた。 Therefore, according to the prior art as described above,
For example, it is not possible to automatically detect the occurrence of a disconnection in an optical transmission system that does not have a light receiving system, such as a medical optical fiber used in a laser scalpel, etc., and in order to detect it, it is necessary to It is troublesome that the optical fiber must be switched to a measuring optical pulse generating circuit, and it is impossible to constantly monitor the occurrence of a break in the optical fiber.
そこで本発明は、光フアイバ使用中に於ける断
線発生を常時監視し、例え受光系を有さざる光伝
送系にあつても、断線の発生を光入射側で即座に
検知し得る新規な光フアイバの断線検出方法を提
供することを目的とする。 Therefore, the present invention has developed a new optical fiber that constantly monitors the occurrence of disconnection while using the optical fiber, and can immediately detect the occurrence of disconnection on the light input side, even in an optical transmission system that does not have a light receiving system. It is an object of the present invention to provide a method for detecting fiber breakage.
上記目的を達成するために本発明は、コアにこ
れよりも屈折率の低い第１クラツド層を被覆し、
該第１クラツド層にこれよりも更に屈折率の低い
第２クラツド層を被覆してなる光フアイバを光伝
送路として使用し、該光フアイバの破断時にその
破断点で反射される散乱光を前記第１クラツド層
と第２クラツド層との境界面で反射させながら光
入射側に伝播させ、その伝播された光を光入射側
から検知することにより、光フアイバの断線発生
を検出するようにしたものである。 In order to achieve the above object, the present invention covers the core with a first cladding layer having a lower refractive index than the first cladding layer,
An optical fiber in which the first cladding layer is coated with a second cladding layer having a lower refractive index than the first cladding layer is used as an optical transmission path, and when the optical fiber is broken, the scattered light reflected at the breaking point is transmitted to the optical fiber. The occurrence of a break in the optical fiber is detected by transmitting the light to the light incident side while reflecting it at the interface between the first cladding layer and the second cladding layer, and detecting the propagated light from the light incident side. It is something.
以下、本発明を図面に示す実施例に基づいて説
明する。 Hereinafter, the present invention will be explained based on embodiments shown in the drawings.
第１図Ａは本発明方法に適用し得る光フアイバ
１の一例を示す正面図、同図Ｂはその断面図であ
る。 FIG. 1A is a front view showing an example of an optical fiber 1 applicable to the method of the present invention, and FIG. 1B is a sectional view thereof.
図中、２は屈折率η1の中心コア、３は中心コア
の外周に同心的に被覆された屈折率η2の第１クラ
ツド層、４は第１クラツド層の外周に同心的に被
覆された屈折率η3の第２クラツド層、５は更にそ
の第２クラツド層の外周に同心的に被覆された合
成樹脂材等からなる保護被覆層であつて、これら
中心コア２、第１クラツド層３及び第２クラツド
層４のそれぞれの屈折率η1，η2及びη3は、η1＞η2
＞η3に選定され、第１クラツド層は光フアイバ１
の破断時に発生する後方散乱光に対して第２のコ
アとなる。 In the figure, 2 is a central core with a refractive index η 1 , 3 is a first cladding layer with a refractive index η 2 that is concentrically coated around the outer periphery of the central core, and 4 is a first cladding layer that is concentrically coated around the outer periphery of the first cladding layer. The second cladding layer 5 having a refractive index η 3 is a protective coating layer made of a synthetic resin material, etc., which is concentrically coated around the outer periphery of the second cladding layer. The refractive indices η 1 , η 2 and η 3 of the second cladding layer 3 and the second cladding layer 4 are such that η 1 >η 2
>η 3 , and the first cladding layer is optical fiber 1.
serves as a second core for backscattered light generated when the
次に、上記光フアイバ１を使用した光伝送系の
一例を第２図により説明する。 Next, an example of an optical transmission system using the above optical fiber 1 will be explained with reference to FIG.
６はレーザ発振器等の発光源、７は集光レンズ
であつて、発光源６からの光信号が集光レンズ７
によつて集光されて光フアイバ１の中心コア２内
に入射される。 6 is a light emitting source such as a laser oscillator, 7 is a condenser lens, and an optical signal from the light source 6 is transmitted to the condenser lens 7.
The light is condensed by the light beam and enters the central core 2 of the optical fiber 1.
８は光フアイバ１の光入射端面近傍に於ける第
２クラツド層４及び保護被覆層５を一部除去して
形成された切欠部９に配設されたフオトダイオー
ド等の光検出器であつて、この光検出器８からの
検出出力が例えば発光源６に供給されて発光源６
からの光信号発生を停止させる。 Reference numeral 8 denotes a photodetector such as a photodiode, which is disposed in a notch 9 formed by partially removing the second cladding layer 4 and the protective coating layer 5 near the light incident end face of the optical fiber 1. , the detection output from this photodetector 8 is supplied to, for example, the light emitting source 6.
Stops the generation of optical signals from.
以上のように構成された光伝送系に於いて、常
時は発光源６からの光信号が光フアイバ１の中心
コア２内に入射され、該コア内を破線図示のよう
にコアと第１クラツド層３との境界面で全反射さ
れながら光出射側に伝播され、したがつて光検出
器８には光が照射されず、検出出力は得られな
い。 In the optical transmission system configured as described above, an optical signal from the light emitting source 6 is normally input into the central core 2 of the optical fiber 1, and the core and the first clad are connected within the core as shown by the broken line. The light is propagated to the light output side while being totally reflected at the interface with the layer 3, so the light is not irradiated onto the photodetector 8 and no detection output is obtained.
ところが、送信中に第２図に示すように光フア
イバ１が途中で破断すると、中心コア２内を光出
射側に伝播していた光がその破断点１０でフレネ
ル反射され、散乱光となつて通常の光信号より高
次のモードの光となる。 However, if the optical fiber 1 breaks during transmission as shown in FIG. 2, the light that was propagating within the central core 2 toward the light output side is Fresnel-reflected at the break point 10 and becomes scattered light. The light is in a higher order mode than a normal optical signal.
これにより、屈折率η2の第１クラツド層３が前
記散乱光に対して第２のコアとなり、散乱光は第
２図及び第３図に示すように第１クラツド層３内
を該クラツド層と第２クラツド層４との境界面で
反射されながら光入射側に伝播される。そして、
その伝播された光が光入射端面近傍に達すると、
切欠部９位置に於いて第２クラツド層４が除去さ
れているから、その切欠部９から外部に放射さ
れ、これが光検出器８によつて検知されて光フア
イバ１の断線発生が検出されることとなり、更に
光検出器８の検出出力によつて発光源６の光信号
発生が停止される。 As a result, the first cladding layer 3 with a refractive index η 2 serves as a second core for the scattered light, and the scattered light travels through the first cladding layer 3 as shown in FIGS. 2 and 3. The light is propagated to the light incident side while being reflected at the interface between the light and the second cladding layer 4. and,
When the propagated light reaches the vicinity of the light incidence end face,
Since the second cladding layer 4 is removed at the position of the notch 9, radiation is emitted to the outside from the notch 9, and this is detected by the photodetector 8, thereby detecting the occurrence of a break in the optical fiber 1. Therefore, the light signal generation of the light emitting source 6 is further stopped by the detection output of the photodetector 8.
なお、本例では光検出器８の出力によつて発光
源６の発光を停止させる場合について説明した
が、これに代えて警報を発生させるようにしても
良い。 In this example, a case has been described in which the light emission of the light source 6 is stopped by the output of the photodetector 8, but instead of this, an alarm may be generated.
以上のように本発明によれば、光フアイバの破
断点で生じる後方散乱光をクラツド層を通じて光
入射側に伝播させ、これを光検出器で検知するこ
とにより光フアイバの破断発生を検出することが
できるから、光フアイバ内に信号光を伝播させな
がらしかもその信号光に何ら障害を与えることな
く、使用中の光フアイバの断線発生を光入射側か
ら常時監視することができるという優れた効果を
有する。 As described above, according to the present invention, occurrence of a break in the optical fiber can be detected by propagating backscattered light generated at the break point of the optical fiber to the light incident side through the cladding layer and detecting this with a photodetector. Because of this, it has the excellent effect of allowing signal light to propagate within the optical fiber without causing any damage to the signal light, and constantly monitoring the occurrence of breakage in the optical fiber during use from the light input side. have
また、光検出器の検出出力によつて発光源の発
光を即座に停止させることが可能となり、したが
つて殊に医療用器具として使用されるレーザメス
の如く手術中に光フアイバが破断してその破断点
から散乱するレーザ光によつて健康な生体に損傷
を与えるという危惧も解消され、手術を安全に行
なうことができる。 In addition, the detection output of the photodetector makes it possible to immediately stop the light emission of the light source. The fear of damaging a healthy living body due to laser light scattered from the fracture point is also eliminated, and surgery can be performed safely.
更に、本発明の場合には光フアイバ内又はその
コネクタ等に光漏洩検知用の特殊な部材を配設す
る必要もないので光フアイバ径を極めて細くする
ことができ、しかも受光系を有さざる光伝送系に
あつても断線検出ができるから、特に手術に使用
する医療用レーザメスを始めとする各種の医療用
光フアイバ製品に適用して大変有用性の高いもの
である。 Furthermore, in the case of the present invention, there is no need to provide a special member for detecting light leakage within the optical fiber or its connector, so the diameter of the optical fiber can be made extremely thin, and there is no need for a light receiving system. Since disconnection can be detected even in optical transmission systems, it is extremely useful when applied to various medical optical fiber products, including medical laser scalpels used in surgeries.
勿論、本発明方法は上記に限らず、他の任意の
光伝送系に適用し得ることは云うまでもない。 It goes without saying that the method of the present invention is not limited to the above, but can be applied to any other optical transmission system.
第１図Ａ及びＢは本発明方法に適用し得る光フ
アイバの一例を示す正面図及び断面図、第２図は
本発明方法の説明図、第３図は光フアイバ破断時
にその破断点で反射される散乱光の伝播状態を示
す光フアイバの縦断面図である。
符号の説明、１……光フアイバ、２……中心コ
ア、３……第１クラツド層、４……第２クラツド
層、６……発光源、７……集光レンズ、８……光
検出器、９……切欠部、１０……破断点。
Figures 1A and B are a front view and a sectional view showing an example of an optical fiber that can be applied to the method of the present invention, Figure 2 is an explanatory diagram of the method of the present invention, and Figure 3 is a reflection at the breaking point when the optical fiber is broken. FIG. 3 is a vertical cross-sectional view of an optical fiber showing the propagation state of scattered light. Explanation of symbols, 1... Optical fiber, 2... Central core, 3... First cladding layer, 4... Second cladding layer, 6... Light emitting source, 7... Condensing lens, 8... Photo detection Container, 9... Notch, 10... Breaking point.
Claims (1)
層を被覆し、該第１クラツド層にこれよりも更に
屈折率の低い第２クラツド層を被覆してなる光フ
アイバを光伝送路として使用し、該光フアイバの
破断時にその破断点で反射される散乱光を前記第
１クラツド層と第２クラツド層との境界面で反射
させながら光入射側に伝播させ、その伝播された
光を光入射側から検知することにより、光フアイ
バの断線発生を検出するようにしたことを特徴と
する光フアイバの断線検出方法。1. An optical fiber in which the core is coated with a first cladding layer having a lower refractive index, and the first cladding layer is coated with a second cladding layer having an even lower refractive index is used as an optical transmission line. When the optical fiber is broken, the scattered light reflected at the break point is reflected at the interface between the first cladding layer and the second cladding layer and propagated to the light incidence side, and the propagated light is transmitted to the light incidence side. A method for detecting a break in an optical fiber, characterized in that the occurrence of a break in an optical fiber is detected by detecting from the side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57190091A JPS5979137A (en) | 1982-10-28 | 1982-10-28 | Detection for disconnection of optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57190091A JPS5979137A (en) | 1982-10-28 | 1982-10-28 | Detection for disconnection of optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5979137A JPS5979137A (en) | 1984-05-08 |
| JPH0151136B2 true JPH0151136B2 (en) | 1989-11-01 |
Family
ID=16252212
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57190091A Granted JPS5979137A (en) | 1982-10-28 | 1982-10-28 | Detection for disconnection of optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5979137A (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20050071967A (en) * | 2004-01-05 | 2005-07-08 | 삼성전자주식회사 | Optical transmitter of bidirectional optical module and method for fabricating the same |
| KR100616549B1 (en) | 2004-01-16 | 2006-08-28 | 주식회사 골드텔 | Optical cable for optical signal detection and method of manufacturing same |
| KR100576152B1 (en) | 2004-01-16 | 2006-05-03 | 주식회사 골드텔 | Optical signal detector |
| KR100651238B1 (en) | 2005-04-27 | 2006-11-30 | 주식회사 골드텔 | Optical signal detector |
| EP2555348A4 (en) | 2010-03-30 | 2017-12-20 | Fujikura Ltd. | Light intensity monitoring circuit and fiber laser system |
| DE102011009996B4 (en) * | 2011-02-01 | 2016-11-03 | Roland Berger | Fiber breakage monitoring for an optical fiber |
| JP7145630B2 (en) * | 2018-03-28 | 2022-10-03 | 古河電気工業株式会社 | OPTICAL FIBER BREAK DETECTION SYSTEM AND OPTICAL FIBER BREAK DETECTION METHOD |
-
1982
- 1982-10-28 JP JP57190091A patent/JPS5979137A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5979137A (en) | 1984-05-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5276749B2 (en) | Light intensity monitor circuit and fiber laser system | |
| JP6580995B2 (en) | Low mode high power fiber coupler | |
| US7146073B2 (en) | Fiber delivery system with enhanced passive fiber protection and active monitoring | |
| CN113169503B (en) | Laser device | |
| US20210177516A1 (en) | Optical probe, medical laser probe, and cauterization device | |
| US4623788A (en) | Fiber optic system with self test used in fire detection | |
| US5463710A (en) | Laser - optical fiber tuning and control system | |
| JP2018180449A (en) | Optical power monitor device and laser device | |
| JPH0551298B2 (en) | ||
| CN103688204B (en) | Bonder for fiber waveguide | |
| US20250164717A1 (en) | External Laser Source Physical Contact Verification Of A Fiber Optic Ferrule | |
| JPH0151136B2 (en) | ||
| JPS6259918B2 (en) | ||
| JPH0579934B2 (en) | ||
| JP2000231029A (en) | Optical connector with optical filter | |
| JPH02181708A (en) | Two core type temperature detecting optical fiber | |
| JP6988019B2 (en) | Laser device | |
| US20190079169A1 (en) | Monostatic laser rangefinder device | |
| CN221572873U (en) | Laser coupler and optical fiber therapeutic machine | |
| KR100232635B1 (en) | Optical fiber failure detection device for laser transmission | |
| JP2677290B2 (en) | Optical fiber line test method | |
| JPH10332956A (en) | Filter insertion type optical branching device | |
| JP2511999B2 (en) | Liquid detection optical fiber and liquid detection system using the same | |
| JPS5968641A (en) | Detection for damage of fiber for energy transmission | |
| JPS59225330A (en) | System for detecting fiber breaking point |