JPH0518769B2 - - Google Patents
Info
- Publication number
- JPH0518769B2 JPH0518769B2 JP60149966A JP14996685A JPH0518769B2 JP H0518769 B2 JPH0518769 B2 JP H0518769B2 JP 60149966 A JP60149966 A JP 60149966A JP 14996685 A JP14996685 A JP 14996685A JP H0518769 B2 JPH0518769 B2 JP H0518769B2
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- face
- optical
- gas torch
- present
- 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 - Lifetime
Links
- 239000013307 optical fiber Substances 0.000 claims description 66
- 238000003672 processing method Methods 0.000 claims description 15
- 238000012545 processing Methods 0.000 claims description 9
- 230000003287 optical effect Effects 0.000 description 14
- 238000005498 polishing Methods 0.000 description 13
- 238000000034 method Methods 0.000 description 11
- 230000000694 effects Effects 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 239000000835 fiber Substances 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- 239000011253 protective coating Substances 0.000 description 1
- 238000012958 reprocessing Methods 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/255—Splicing of light guides, e.g. by fusion or bonding
- G02B6/2552—Splicing of light guides, e.g. by fusion or bonding reshaping or reforming of light guides for coupling using thermal heating, e.g. tapering, forming of a lens on light guide ends
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は光フアイバの端面加工方法に関するも
のである。更に詳しくは、光コネクタ、光フアイ
バ付発光素子及び光フアイバのＶ溝による接続、
光フアイバのスリーブによる接続等の永久接続等
に利用される光フアイバの端面加工方法に関する
ものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for processing an end face of an optical fiber. More specifically, optical connectors, light-emitting elements with optical fibers, connections using V-grooves of optical fibers,
The present invention relates to a method for processing the end face of an optical fiber used for permanent connection such as connection using an optical fiber sleeve.
〔従来の技術とその問題点〕
光コネクタ方式は光通信システムにおける装置
と光フアイバや光フアイバと光フアイバを効率よ
くかつ脱着可能な接続を行う方式で、光通信シス
テムの建設・保守あるいは実験等に必要欠くべか
らざる重要な接続要素となつている。[Conventional technology and its problems] The optical connector method is a method for efficiently and removably connecting devices and optical fibers in optical communication systems, or optical fibers to optical fibers, and is useful for construction, maintenance, experimentation, etc. of optical communication systems. It has become an indispensable and important connection element.
光コネクタによる接続を行う場合、接続される
べきそれぞれの光フアイバのコア（光の通る部
分）とコアの端面を完全に一致させることが基本
となる。 When making a connection using an optical connector, it is essential that the core (portion through which light passes) of each optical fiber to be connected be completely aligned with the end surface of the core.
たとえば、マルチモード光フアイバでは直径
50μｍのコアとコアを、さらにシングルモード光
フアイバでは10μｍのコアとコアを完全に合わせ
ることが必要となるが、これには接続部で発生す
る種々の要因による障害の除去対策を含めてかな
りの困難がともなう。 For example, for multimode optical fiber, the diameter
It is necessary to perfectly match the 50 μm core to core, and in the case of single mode optical fiber, the 10 μm core to core. It comes with difficulties.
光コネクタによる接続は、接続部で発生する光
損失の多少等によつて評価されるが、一般に光コ
ネクタにおける接続損失の要因はつぎのように接
続技術による要因と光フアイバ固有の要因に分け
ることができる。 Connections using optical connectors are evaluated based on the amount of optical loss that occurs at the connection part, but in general, the causes of connection loss in optical connectors can be divided into factors due to the connection technology and factors specific to the optical fiber, as shown below. can.
ａ 接続技術上の要因
軸ずれによる損失
光フアイバの端面または軸の角度ずれによ
る損失
光フアイバの端面間の間隙ずれによる損失
光フアイバ端面の不完全性（端面粗さ）に
よる損失
上記接続技術上の要因を第３図に示す。a Factors related to connection technology Loss due to axis misalignment Loss due to angular misalignment of the optical fiber end face or axis Loss due to gap misalignment between the optical fiber end faces Loss due to imperfection (end face roughness) of the optical fiber end face Due to the above connection technology The factors are shown in Figure 3.
ｂ 光フアイバ固有の要因
コア直径の不一致による損失
光フアイバ端面のフレネル反射による損失
コアとクラツドの偏心による損失
光フアイバの種類の違いによる損失
このように光コネクタ方式による接続に際して
は種々の要因による接続損失が常に併存する。こ
のため光コネクタの機構、工作精度、使用材料、
心出し技術、光フアイバの製造方法、ならびに端
面加工方法にこれまで種々の改良が加えられてき
ているが接続損失の要因を皆無にすることは困難
である。b Factors unique to optical fibers Loss due to mismatch in core diameter Loss due to Fresnel reflection on the end face of the optical fiber Loss due to eccentricity between the core and cladding Loss due to differences in the type of optical fiber As described above, connection by optical connector method is caused by various factors. Loss always coexists. For this reason, the mechanism, work precision, materials used, etc. of optical connectors,
Although various improvements have been made to centering techniques, optical fiber manufacturing methods, and end face processing methods, it is difficult to completely eliminate the causes of splice loss.
光コネクタ方式の接続を行う場合、従来の光フ
アイバ端面加工方法の概要を述べればつぎのとお
りである。 When connecting using an optical connector method, a conventional method for processing the end face of an optical fiber will be summarized as follows.
まず光フアイバ心線の端末保護被覆を完全に除
去して、コネクタのフエルール（コネクタの中子
（なかご））に装着後、フエルールごと光フアイバ
の端面を平面研磨してコネクタ外装部を組み立て
るという過程を経て実用に供されるのが一般的で
ある。 First, the terminal protective coating of the optical fiber core wire is completely removed, and the end face of the optical fiber is polished together with the ferrule after being attached to the ferrule of the connector (the core of the connector), and the exterior part of the connector is assembled. Generally, it is put into practical use after undergoing a process.
光フアイバ端面の平面研磨には多くは機械的研
磨機が使用されるが、前記接続損失要因との関連
から端面の粗さ、端面の光軸に対する直角度、端
面の平面度等にサブミクロン級の精度が要求され
る。たとえば
面粗さ0.1μｍ以下、直角度0.1゜以下、平面度1μ
ｍ以下の如きである。 Mechanical polishing machines are often used for flat polishing of optical fiber end faces, but in relation to the splice loss factors mentioned above, the roughness of the end face, the perpendicularity of the end face to the optical axis, the flatness of the end face, etc. can be adjusted to submicron level. accuracy is required. For example, surface roughness 0.1μm or less, perpendicularity 0.1° or less, flatness 1μm
m or less.
このため光フアイバ端面研磨機はかなり高価な
ものとなる。 Therefore, the optical fiber end face polishing machine becomes quite expensive.
機械的研磨は通常、研削・粗研磨・仕上研磨・
バフ研磨の４工程を経るので研磨時間も30〜40分
を必要とする。 Mechanical polishing usually includes grinding, rough polishing, final polishing,
Since it goes through four steps of buffing, the polishing time requires 30 to 40 minutes.
また光コネクタとして接続する際は端面と端面
を密着させるのでこれに反復脱着操作が加えられ
た場合、端面が損傷を受け易い等の問題点があ
る。 Furthermore, when connecting as an optical connector, the end faces are brought into close contact with each other, so if repeated attachment/detachment operations are applied, there is a problem that the end faces are easily damaged.
本発明はこれまで述べてきたような従来の光フ
アイバ端面加工方法と異なり、機械的研磨が不要
で加工が容易であり、かつ接続損失要因を極力排
除しながら安価で効率のよい光フアイバの端面加
工方法を提供することを目的とするものである。 Unlike the conventional optical fiber end face processing methods described above, the present invention does not require mechanical polishing, is easy to process, and eliminates splice loss factors as much as possible while producing an inexpensive and efficient optical fiber end face. The purpose is to provide a processing method.
上記問題点を解決し、発明の目的を達成するた
め次のように構成したことを特徴とする。すなわ
ち、第１図の光フアイバの端面加工方法の説明図
において、光フアイバ１を固定し、かつこの光フ
アイバを長さ方向に移動できる光フアイバ保持具
２と固定された光フアイバの長さ方向に対向させ
たガストーチ火口３との間にこれらと直角になる
ように微小孔付き遮熱板４を置き、光フアイバを
マイクロスコープ５で確認しながら光フアイバ保
持具を移動させて微小孔６に挿入して光フアイバ
を必要とする長さだけガストーチ火口側に出し、
この部分をガストーチから噴射させた酸水素炎等
により加熱溶融し、光フアイバの表面張力を利用
して、光フアイバの端面を球面状に加工すること
を特徴とする。
In order to solve the above problems and achieve the purpose of the invention, the present invention is characterized by the following structure. That is, in the explanatory diagram of the optical fiber end face processing method shown in FIG. 1, an optical fiber holder 2 that fixes the optical fiber 1 and can move the optical fiber in the longitudinal direction and A heat shield plate 4 with micro holes is placed between and at right angles to the gas torch nozzle 3 facing the gas torch, and the optical fiber holder is moved to the micro holes 6 while checking the optical fiber with a microscope 5. Insert the optical fiber and bring it out to the gas torch crater side for the required length.
This part is heated and melted using an oxyhydrogen flame or the like injected from a gas torch, and the end surface of the optical fiber is processed into a spherical shape using the surface tension of the optical fiber.
この本発明に係る上記加工方法は次のような利
点を有している。 The above processing method according to the present invention has the following advantages.
光フアイバ端末の被覆除去と端末のカツトま
では従来の機械的研磨と同一過程を踏むが、以
降本発明は端面を必要とする球面に加工するた
めの条件として、
ｄ：微小孔付き遮熱板とガストーチ火火口ま
での距離
ｌ：遮熱板の微小孔かｒガストーチ火口側に
出す光フアイバの長さ
ｔ：加熱溶融時間
ｐ：ガス圧
の中でｄ，ｔ，ｐは予め設定しておけばよく、
ｌの設定も通常のマイクロメータ(1/100mm)の
精度を持つ保持具で十分であり、光フアイバも
軽く固定するだけでよい。 The process of removing the coating from the optical fiber terminal and cutting the terminal is the same as conventional mechanical polishing, but from now on, the present invention has the following conditions for processing the end face into the required spherical surface: d: Heat shield plate with micro holes. and the distance to the gas torch crater l: Length of the optical fiber extending from the small hole in the heat shield plate to the gas torch crater side t: Heating and melting time p: Set d, t, and p in advance in the gas pressure. By the way,
A holder with the accuracy of a normal micrometer (1/100 mm) is sufficient for setting l, and the optical fiber only needs to be lightly fixed.
また、光フアイバ端面の加熱溶融に要する時
間は数秒以内ときわめて短い。 Further, the time required to heat and melt the end face of the optical fiber is extremely short, within several seconds.
さらに調整を必要とするのはｌだけであるこ
とから加工の再現在が良好である。 Since only l requires further adjustment, reprocessing is easy.
従つて加工方法が容易で、加工の再現性がよ
い。 Therefore, the processing method is easy and the processing reproducibility is good.
光フアイバ端面の平面研磨に使用される機械
的研磨機は高い仕上精度が要求されるのでかな
り高価であるが、本発明の端面加工方法では各
構成物にガス供給源を含めても上記機械的研磨
機よりもきわめて低価格でありまた加工時間も
非常に短い。 Mechanical polishing machines used for flat polishing of optical fiber end faces are required to have high finishing accuracy and are therefore quite expensive. However, in the end face processing method of the present invention, even if each component includes a gas supply source, The cost is much lower than that of a polishing machine, and the processing time is also very short.
本発明により端面を球面状に加工を行つたも
のは
(1) 一方の端面から出た光は端面の球面レンズ作
用により絞られてもう一方の受光端面に入る。 According to the present invention, the end face is processed into a spherical shape (1) The light emitted from one end face is focused by the spherical lens action of the end face and enters the other light-receiving end face.
(2) 軸方向から角度がずれた光は受光端面の球面
レンズ作用により軸に平行に曲げられる。(2) Light deviated from the axial direction is bent parallel to the axis by the action of the spherical lens on the receiving end surface.
これらの作用により、端面間の間隙、角度ず
れ光軸ずれに対して、従来の平面対平面の接続
よりも接続損失に対する許容度が大きい。 Due to these effects, tolerance for connection loss is greater than in conventional plane-to-plane connections with respect to gaps between end faces, angular deviations, and optical axis deviations.
たとえば、開口数0.2、コア径50μｍのグレー
デツドインデツクス形光フアイバを球面の半径
がおよそ100μｍの球面になるよう加工したも
のは光フアイバ両端面の間隙が150μｍ以内で
あればよいという結果が得られている。 For example, when a graded index optical fiber with a numerical aperture of 0.2 and a core diameter of 50 μm is processed into a spherical surface with a radius of approximately 100 μm, the gap between both end faces of the optical fiber should be within 150 μm. It has been obtained.
接続の際、端面と端面を密着させなくともよ
いので端面は損傷されない。 During connection, the end faces do not need to be brought into close contact with each other, so the end faces are not damaged.
本発明は加熱溶融方法であるため
ｄ：微小孔付き遮熱板とガストーチ火口まで
の距離
ｌ：遮熱板の微小孔からガストーチ火口側に
出す光フアイバの長さ
ｔ：加熱溶融時間
ｐ：ガス圧
の設定条件の組み合わせを変えることにより
種々の球面半径を容易に得ることができる。 Since the present invention is a heating melting method, d: Distance between the heat shield plate with micro holes and the gas torch crater l: Length of the optical fiber coming out from the micro holes in the heat shield plate to the gas torch crater side t: Heat melting time p: Gas Various spherical radii can be easily obtained by changing the combination of pressure setting conditions.
最も損失の小さい間隙ずれｄと球面半径Ｒと
の関係は次式で与えられる。 The relationship between the gap deviation d with the smallest loss and the spherical radius R is given by the following equation.
ｄ≦2a2Ｒ／ｎ−１／〔（Ｎ／ｎ）2（Ｂ／ｎ−１）2
＋a2〕
ここでａはコア半径、Ｎは光フアイバ中心で
の開口数、ｎはコア中心の屈折率である。この
条件を満たす場合はフレネル反射（対向する端
面と端面の間で伝搬光が反射する現象）損失だ
けとなる。この式から接続する両光フアイバの
端面の球面半径は同一でなくてもよいことが分
る。 d≦2a 2 R/n-1/[(N/n) 2 (B/n-1) 2
+a 2 ] Here, a is the core radius, N is the numerical aperture at the center of the optical fiber, and n is the refractive index at the center of the core. If this condition is satisfied, only Fresnel reflection (a phenomenon in which propagating light is reflected between opposing end faces) is lost. From this equation, it can be seen that the spherical radii of the end faces of both optical fibers to be connected do not have to be the same.
何れの形の光フアイバに対しても本発明の加
工方法で同様な効果が得られ、特にシングルモ
ードフアイバについては大きい効果が期待され
る。 Similar effects can be obtained by the processing method of the present invention for any type of optical fiber, and particularly great effects are expected for single mode fibers.
次に本発明の実験例データを示。 Next, experimental data of the present invention is shown.
本発明による光フアイバー端面加工方法で端面
を半径がおよそ100μｍになるように加工した。 The end face was processed to have a radius of approximately 100 μm using the optical fiber end face processing method according to the present invention.
開口数0.2、コア径50μｍのグレーデツドインデ
ツクス形光フアイバの端面間隙に対する定常励振
による接続損失を測定した結果を端面が平面対平
面の場合との比較で第２図に示す。 Figure 2 shows the results of measuring the splice loss due to steady excitation with respect to the gap between the end faces of a graded index optical fiber with a numerical aperture of 0.2 and a core diameter of 50 μm, comparing the results when the end faces are flat versus flat.
この結果によれば本発明によるものは、光フア
イバ両端面の間隙がおよそ150μｍまでは接続損
失に変化はみられない。 According to the results, in the case of the present invention, no change in splice loss is observed up to a gap of approximately 150 μm between both end faces of the optical fiber.
本発明は上記のように構成されているので次の
ような効果を有する。
Since the present invention is configured as described above, it has the following effects.
加工方法が容易で加工の再現性がよい。 The processing method is easy and the processing reproducibility is good.
光フアイバ端面加工に要する（設備）費用が
機械的研磨に比べてきわめて低価格である。 The (equipment) cost required for optical fiber end face processing is extremely low compared to mechanical polishing.
本発明で加工した光フアイバの端面は接続の
際、端面と端面を密着させなくともよいので接
続損失に対する軸ずれ、角度ずれ、間隙ずれの
許容度が大きい。 Since the end faces of the optical fiber processed according to the present invention do not need to be brought into close contact with each other during connection, there is a large tolerance for axial misalignment, angular misalignment, and gap misalignment with respect to splicing loss.
接続時においても光フアイバの端面が損傷さ
れない。 The end face of the optical fiber is not damaged even during connection.
本発明の加工方法によれば端面に対し種々の
半径を有する球面の加工が容易にできる。 According to the processing method of the present invention, spherical surfaces having various radii can be easily processed with respect to the end face.
接続する両光フアイバの端面の球面半径は同
一でなくてもよい。 The spherical radii of the end faces of both optical fibers to be connected may not be the same.
本発明による光フアイバの端面加工方法はマ
ルチモードフアイバ（グレーデツドインデツク
ス形、ステツプインデツクス形）およびシング
ルモードフアイバの何れにも適用できる。 The optical fiber end face processing method according to the present invention can be applied to both multimode fibers (graded index type, step index type) and single mode fibers.
本発明による光フアイバの端面加工方法を適
用した場合は、従来の平面対平面の接続に要求
されるような精度維持を考慮しなくてもよい。 When the optical fiber end face processing method according to the present invention is applied, there is no need to consider maintaining precision as required for conventional plane-to-plane connections.
第１図は本発明に係る光フアイバの端面加工方
法の説明図、第２図は本発明と平面対平面との接
続損失の比較を示す図、第３図は接続技術上の接
続損失の要因を示す図である。
１…光フアイバ、２…光フアイバ保持具、３…
ガストーチ火口、４…微小孔付遮熱板、５…マイ
クロスコープ、６…微小孔。
Fig. 1 is an explanatory diagram of the optical fiber end face processing method according to the present invention, Fig. 2 is a diagram showing a comparison of splice loss between the present invention and a plane-to-plane splice, and Fig. 3 is a diagram showing factors of splice loss in splicing technology. FIG. 1... Optical fiber, 2... Optical fiber holder, 3...
Gas torch crater, 4... Heat shield plate with micro holes, 5... Microscope, 6... Micro holes.
Claims (1)
長さ方向に移動できる光フアイバ保持具と固定さ
れた光フアイバの長さ方向に対向させたガストー
チ火口との間にこれらと直角になるように微小孔
付き遮熱板を置き、光フアイバを遮熱板の微小孔
に挿入してガストーチ火口側に必要長さだけ出
し、ガストーチ火口から炎を定圧で定時間噴射さ
せ、光フアイバ端面を長さ方向から加熱溶融し、
光フアイバ端面を球面状に加工することを特徴と
する光フアイバの端面加工方法。1. A micro-instrument is made between an optical fiber holder that fixes an optical fiber and can move the optical fiber in the length direction, and a gas torch nozzle that is opposed to the fixed optical fiber in the length direction. Place a heat shield plate with holes, insert the optical fiber into the micro holes in the heat shield plate, extend the necessary length toward the gas torch mouth side, and inject flame at a constant pressure from the gas torch mouth for a fixed period of time, so that the end face of the optical fiber is exposed in the length direction. Heat and melt from
An optical fiber end face processing method characterized by processing an optical fiber end face into a spherical shape.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60149966A JPS6212632A (en) | 1985-07-10 | 1985-07-10 | Method of processing end face of optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60149966A JPS6212632A (en) | 1985-07-10 | 1985-07-10 | Method of processing end face of optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6212632A JPS6212632A (en) | 1987-01-21 |
| JPH0518769B2 true JPH0518769B2 (en) | 1993-03-12 |
Family
ID=15486502
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60149966A Granted JPS6212632A (en) | 1985-07-10 | 1985-07-10 | Method of processing end face of optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6212632A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0521041Y2 (en) * | 1986-04-11 | 1993-05-31 |
-
1985
- 1985-07-10 JP JP60149966A patent/JPS6212632A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6212632A (en) | 1987-01-21 |
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