JPH0642008B2 - Image fiber manufacturing method - Google Patents
Image fiber manufacturing methodInfo
- Publication number
- JPH0642008B2 JPH0642008B2 JP60093580A JP9358085A JPH0642008B2 JP H0642008 B2 JPH0642008 B2 JP H0642008B2 JP 60093580 A JP60093580 A JP 60093580A JP 9358085 A JP9358085 A JP 9358085A JP H0642008 B2 JPH0642008 B2 JP H0642008B2
- Authority
- JP
- Japan
- Prior art keywords
- image
- image fiber
- fiber
- base material
- twisted
- 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
Description
【発明の詳細な説明】 〈産業上の利用分野〉 本発明は画像伝送用イメージファイバの製造方法に係わ
る。DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a method of manufacturing an image fiber for image transmission.
〈従来の技術〉 イメージフアイバは、細径で可とう性を有するため、狭
奥部を観察するための医療用あるいは工業用の内視鏡に
広く利用されている。かかるイメージフアイバは、通常
第４図に示す様なイメージフアイバ製造装置によつて製
造されている。即ち第４図に示す如く多数本のガラスフ
アイバ１を平行かつ稠密にガラスのジヤケツト管２の中
に配列したイメージフアイバ母材、あるいは、かかる母
材を加熱し密実一体化した固体母材７Ｓの下端をヒータ
３によつて加熱溶融延伸することによつて製造される。
製造されたイメージフアイバ７は、その断面図を第５図
に示す如く、多数本のコア４がジヤケツト６と共通のク
ラツド５の中に平行に配置され、コア４の相互間の関係
位置はイメージフアイバ全長にわたつて変らない。<Prior Art> Image fibers have a small diameter and flexibility, and are therefore widely used for medical or industrial endoscopes for observing a narrow inner part. Such an image fiber is usually manufactured by an image fiber manufacturing apparatus as shown in FIG. That is, as shown in FIG. 4, an image fiber base material in which a large number of glass fibers 1 are arranged in parallel and densely in a glass jacket tube 2 or a solid base material 7S in which such base materials are heated and solidly integrated. It is manufactured by heating, melting, and stretching the lower end of the sheet with the heater 3.
As shown in the sectional view of FIG. 5, the manufactured image fiber 7 has a large number of cores 4 arranged in parallel in the same cladding 5 as the jacket 6, and the relative positions of the cores 4 are shown in the image. It does not change over the length of the fiber.
このようなイメージフアイバを用いたフアイバスコープ
の基本的構成を第６図に示す。第６図に示すフアイバス
コープにおいて、イメージフアイバ７の一方の端面７ａ
上に対物レンズ８ａを介して観測物体９の入射画像９ａ
が結像され、この像はイメージフアイバ７中を第６図に
示す如く伝搬し、他端面７ｂ上に出射画像９ｂを得る。
出射側では出射用レンズ８ｂを介して受像面上に再生像
９ｃを得る。このとき、イメージフアイバ７が捩じれて
いると、その分だけ入射画像９ａと出射画像９ｂは傾く
ことになる。FIG. 6 shows the basic configuration of a fiberscope using such an image fiber. In the fiberscope shown in FIG. 6, one end surface 7a of the image fiber 7 is
An incident image 9a of the observed object 9 is provided on the upper side through the objective lens 8a
Is imaged, this image propagates through the image fiber 7 as shown in FIG. 6, and an outgoing image 9b is obtained on the other end surface 7b.
On the emitting side, a reproduced image 9c is obtained on the image receiving surface via the emitting lens 8b. At this time, if the image fiber 7 is twisted, the incident image 9a and the outgoing image 9b are inclined by that amount.
〈発明が解決しようとする問題点〉 第６図に示されるようなフアイバスコープには、その中
の画像伝送路であるイメージフアイバに関して次のよう
な問題があつた。即ち、まず第一に第４図に示す様な方
法によつて製造するとき、線引におけるイメージフアイ
バの若干のねじれは避けられず、短尺のイメージフアイ
バでは出射画像９ｂは若干回転し、長尺の場合には、ね
じれ状態が更に大きくなる。このため入射画像９ａに対
する出射画像９ｂの向きを予測することが極めて困難に
なる。この場合、出射画像９ｂの向きを修正するために
イメージフアイバを機械的にねじることが一般に行なわ
れる。しかし、これによるねじれ歪によつてイメージフ
アイバが破断することが起きたり、ねじりの繰返しによ
る静疲労が生じやすい等の問題があつた。<Problems to be Solved by the Invention> The fiberscope as shown in FIG. 6 has the following problems regarding the image fiber which is the image transmission path therein. That is, first of all, when manufacturing by the method as shown in FIG. 4, a slight twist of the image fiber in the drawing is inevitable, and in the short image fiber, the outgoing image 9b is slightly rotated and the long image is slightly rotated. In the case of, the twisted state is further increased. Therefore, it becomes extremely difficult to predict the orientation of the outgoing image 9b with respect to the incoming image 9a. In this case, it is common practice to mechanically twist the image fiber to correct the orientation of the output image 9b. However, there are problems that the image fiber may be broken due to the twist distortion and that static fatigue is likely to occur due to repeated twists.
ところで、フアイバスコープはイメージフアイバの出射
画像を直接接眼レンズ８ｂで観察するのが従来の最も基
本的な構成であるが、この場合対物レンズ８ａによりイ
メージフアイバ端面７ａに結像される入射画像が倒立し
た像となり、その伝送画像９ｂを接眼レンズ８ｂにより
虚像として観測するのが普通である。従つて目には倒立
像として見える。この解決方法として、イメージフアイ
バを180°機械的に捩るか、イメージロテータ等の光学
的手段が用いられる。しかし、機械的にイメージフアイ
バを捩る場合、捩りによるイメージフアイバの表面歪が
単位長当り１％を越えると破断したり、静疲労が残り易
く好ましくない。またこの外、イメージフアイバの出射
画像の方向を任意の方向に設定したいことがあるが従来
のものでは簡単にできなかつた。By the way, the fiberscope has the most basic structure of the prior art in which the output image of the image fiber is directly observed by the eyepiece lens 8b. In this case, the incident image formed on the image fiber end face 7a by the objective lens 8a is inverted. The transmitted image 9b is normally observed as a virtual image by the eyepiece 8b. Therefore, it looks like an inverted image to the eyes. As a solution to this, the image fiber is mechanically twisted by 180 ° or an optical means such as an image rotator is used. However, when the image fiber is mechanically twisted, if the surface strain of the image fiber due to the twist exceeds 1% per unit length, the image fiber may be broken or static fatigue may remain, which is not preferable. In addition to this, it is sometimes desired to set the direction of the output image of the image fiber to an arbitrary direction, but this cannot be easily done with the conventional one.
本発明はかかる従来技術の欠陥に鑑みてなされたもの
で、上記のような問題を容易に解決したイメージファイ
バの製造方法を提供することを目的とするものである。The present invention has been made in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a method of manufacturing an image fiber that easily solves the above problems.
〈問題点を解決するための手段〉 かかる目的を達成した本発明のイメージフアイバの製造
方法の構成は、コアを形成する多数本のガラスフアイバ
をジヤケツト管の中に平行かつ稠密に配列し、加熱溶融
密実一体化してイメージフアイバ母材を形成し、該イメ
ージフアイバ母材を、予め加熱溶融し、全長にわたつて
ねじりを与え、ねじり母材を形成し、かかるねじり母材
を線引炉によつて線引きすることを特徴とするものであ
る。<Means for Solving Problems> The structure of the method for manufacturing an image fiber of the present invention that achieves the above object is such that a large number of glass fibers forming a core are arranged in parallel and densely in a jacket tube and heated. An image fiber base material is formed by fusion and solid integration, and the image fiber base material is heated and melted in advance, twisted over the entire length to form a twist base material, and the twist base material is drawn into a drawing furnace. It is characterized by drawing lines.
〈実施例〉 本発明によるイメージフアイバの一実施例の外観図を第
１図に示す。第１図に示す本発明によるイメージフアイ
バによれば、イメージフアバ全長にわたつて、第５図に
示すような断面形状、即ち、多数本のコア４がクラツド
５を介して一定の相互位置関係を保つて配置され、ジヤ
ケツト６で包まれた断面形状を保つとともに、コア４は
長手方向に一定ピツチＰで捩られた構造をもつものであ
る。<Embodiment> An external view of an embodiment of the image fiber according to the present invention is shown in FIG. According to the image fiber according to the present invention shown in FIG. 1, the cross-sectional shape as shown in FIG. 5, that is, a large number of cores 4 having a constant mutual positional relationship via the cladding 5 is provided over the entire length of the image fiber. The core 4 has a structure in which the core 4 is twisted by a constant pitch P in the longitudinal direction while maintaining the cross-sectional shape wrapped by the jacket 6.
第１図に示したような本発明によるイメージフアイバに
よれば、イメージフアイバを構成する多数本のコア４は
ピツチＰでねじられているため、ピツチＰ毎に出射画像
９ｂは同一の方向を取る。従つてピツチＰの間隔で出射
画像の所望の向きの出力を得ることが可能である。従つ
て、所定の長さのフアイバスコープを製造するに当つ
て、所定の長さより１ピツチＰの調整しろを残して本発
明によるイメージフアイバを切断するならば、イメージ
フアイバの対物端面上の観測物体の入射画像９ａとイメ
ージフアイバの接眼端面７ｂ上の出射画像９ｂとが必ず
１個所で同一方向になる場所が得られる。従つてその位
置でイメージフアイバを切断すれば、入射と同一方向の
出射画像９ｂを得る。また倒立像等所望の方向の出射画
像を得たい場合は、その位置は簡単に求められるので、
イメージフアイバの長さをその位置に調整することによ
つて所望の方向の出射画像を得ることができる。本発明
によるイメージフアイバによれば、従来のものの如く、
イメージフアイバの入射画像と出射画像の向きを一致さ
せるために機械的にねじりを加えたり、あるいは光学的
にイメージロテータを用いる必要もない。According to the image fiber according to the present invention as shown in FIG. 1, since a large number of cores 4 constituting the image fiber are twisted by the pitch P, the emission image 9b takes the same direction for each pitch P. . Therefore, it is possible to obtain the output of the output image in the desired direction at intervals of the pitch P. Therefore, in manufacturing a fiberscope having a predetermined length, if the image fiber according to the present invention is cut while leaving an adjustment margin of 1 pitch P from the predetermined length, the observation object on the object end face of the image fiber is obtained. The incident image 9a and the output image 9b on the eyepiece end face 7b of the image fiber are always in one place, and the same direction is obtained. Therefore, if the image fiber is cut at that position, an output image 9b in the same direction as the input is obtained. If you want to obtain an output image in a desired direction such as an inverted image, its position can be easily obtained.
By adjusting the length of the image fiber to that position, an emission image in a desired direction can be obtained. According to the image fiber according to the present invention, like the conventional one,
There is no need to mechanically twist or optically use an image rotator to match the orientation of the incoming and outgoing images of the image fiber.
次に、第１図に示すような本発明によるイメージフアイ
バの製造方法を説明する。(1)本発明によるイメージフ
アイバのの製造方法の実施例によれば、コアを形成する
多数本のガラスフアイバをジヤケツト管の中に平行にか
つ稠密に充填したものを、加熱溶融し、密実一体化した
イメージフアイバ母材を形成し、さらにかかる母材を火
炎旋盤にかけて、さらに母材全長にわたつて一定ピツチ
のねじりを与え、ねじり母材１２を形成し、かかるねじ
り母材１２を第３図に示す如く線引炉１１に挿入し、下
端を加熱溶融線引きしてコア４が所望のピツチＰでねじ
られた第１図に示すようなイメージフアイバを得ること
ができる。Next, a method of manufacturing the image fiber according to the present invention as shown in FIG. 1 will be described. (1) According to the embodiment of the method for producing an image fiber according to the present invention, a large number of glass fibers forming a core are packed in a jacket tube in a parallel and dense manner, which is melted by heating and solidified. An integrated image fiber base material is formed, the base material is further subjected to a flame lathe, and a constant pitch of twist is applied over the entire length of the base material to form a twist base material 12. As shown in the drawing, it is inserted into the drawing furnace 11 and the lower end is heated and melted to draw an image fiber as shown in FIG. 1 in which the core 4 is twisted by the desired pitch P.
上記製造方法によればあらかじめ母材にねじりを付与し
てねじり母材を得ておき、このねじり母材を加熱溶融し
て単に線引きするだけであるので、イメージファイバの
線引きに対して相対的に回転を与える手段を用いること
なく、イメージファイバを作成できるものであり、製造
装置としてより簡単になる。According to the above-described manufacturing method, the base material is preliminarily twisted to obtain the base material, and the base material is simply melted by heating and then drawn. The image fiber can be produced without using a means for imparting rotation, which makes the manufacturing apparatus simpler.
次に本発明のイメージフアイバの実施例について説明す
る。Next, an example of the image fiber of the present invention will be described.
実験例１ コアがGeO2-SiO2系ガラス、クラツドが石英ガラスから
なる外径４００μｍのガラスフアイバ約４０００本を束
ね、外径３０mm、肉厚２mmの石英のジヤケツト管の中に
平行に配列充填し、加熱一体化してイメージフアイバ母
材１０を形成する。次いで第２図に示す如く、線引炉１
１によつて母材下端を加熱溶融し線引きする。線引きに
際し、母材１０と線引きされるイメージフアイバ７とは
相対的に１０rpmの回転が与えられ、１m/minの速度で線
引きされ、外径１mmのイメージフアイバ７を得た。得ら
れたイメージフアイバ７のコア４のピツチＰは、Ｐ＝１
００mmのねじれが与えられ、第１図に示す外観構造をも
つものであつた。かくして得られたイメージフアイバの
入射画像に対する出射画像の方向調整は、わずかな長さ
の調整によつて簡単に行うことができ、優れた画像方向
調整性が得られた。Experimental Example 1 Approximately 4,000 glass fibers having an outer diameter of 400 μm and having a core made of GeO 2 —SiO 2 glass and a quartz glass as a cladding are bundled and arranged in parallel in a quartz jacket tube having an outer diameter of 30 mm and a wall thickness of 2 mm. Then, they are integrated by heating to form the image fiber base material 10. Then, as shown in FIG.
1, the lower end of the base material is heated and melted and drawn. At the time of drawing, the base material 10 and the image fiber 7 drawn were relatively rotated at 10 rpm and drawn at a speed of 1 m / min to obtain an image fiber 7 having an outer diameter of 1 mm. The pitch P of the core 4 of the obtained image fiber 7 is P = 1.
It was given a twist of 00 mm and had the appearance structure shown in FIG. The direction adjustment of the output image with respect to the input image of the image fiber thus obtained can be easily performed by adjusting a slight length, and excellent image direction adjustability was obtained.
実験例２ コアが石英ガラスでクラツドがF-SiO2ガラスからなる外
径１５０μｍのフアイバを約30000本束ね、外径約３０m
m、肉厚1.5mmの石英管の中に平行に配列して充填し、さ
らに加熱一体化してイメージフアイバ母材を得た。この
母材を火炎旋盤によつて全体にわたつて２mmのピツチで
捩り、ねじり母材１２を得た。かかるねじり母材１２を
第３図に示すように、線引炉１１によつて加熱延伸し
て、外径1.5mm、ピツチＰ＝８００mmの第１図に示す外
観構造をもつイメージフアイバを得た。かくして得られ
たイメージフアイバを用いて長さ３０ｍ程度のフアイバ
スコープを作製するに際し、イメージフアイバを約３０
ｍ＋Ｐに切断し、入射画像に対する出射画像の向きの調
整を行なうに当つて、長さ約２００mmつめることによつ
て所望の向きの出射画像が得られた。Experimental Example 2 Approximately 30,000 fibers with an outer diameter of 150 μm consisting of quartz glass as the core and F-SiO 2 glass as the cladding were bundled together and the outer diameter was about 30 m.
A quartz tube with a wall thickness of 1.5 mm and a thickness of 1.5 mm was arranged in parallel and filled, and further heated and integrated to obtain an image fiber base material. This base material was twisted with a 2 mm pitch over the whole by a flame lathe to obtain a twisted base material 12. As shown in FIG. 3, the twisted base material 12 was heated and drawn by a drawing furnace 11 to obtain an image fiber having an outer structure shown in FIG. 1 having an outer diameter of 1.5 mm and a pitch P = 800 mm. . When a fiberscope having a length of about 30 m is produced using the image fiber thus obtained, about 30
When cut to m + P and adjusting the orientation of the outgoing image with respect to the incident image, the outgoing image in the desired direction was obtained by reducing the length by about 200 mm.
実験例２の装置は実験例１の装置に比べてより簡単なも
のとなると共に、ねじり母材のみをあらかじめ作製して
おくことができ、生産効率の向上及び設備の低コスト化
を図ることができる。The apparatus of Experimental Example 2 is simpler than the apparatus of Experimental Example 1, and only the twist base material can be prepared in advance, so that the production efficiency can be improved and the cost of the equipment can be reduced. it can.
〈発明の効果〉 本発明によるイメージフアイバによれば多数本からなる
コアにピツチＰの捩りが与えられているため、入射画像
に対する出射画像の向きの調整はピツチＰの範囲にイメ
ージフアイバを切りつめることによつて極めて容易に行
なうことができる。このため、従来のものの如く、入射
画像に対する出射画像の向きを変えるため、機械的に捩
つたりする必要は全くなく、したがつて、出射画像の向
きの調節の際、機械的捩りによつてイメージフアイバを
破損するといつた不都合はなくなつた。また本発明によ
るイメージフアイバの製造方法によれば、コアが所望の
ピツチで捩られた本発明によるイメージフアイバを極め
て容易に低い製造コストで作製できるようになつた。<Effect of the Invention> According to the image fiber of the present invention, since the twist of the pitch P is given to the core made up of a large number of cores, the orientation of the outgoing image with respect to the incident image is adjusted by cutting the image fiber within the range of the pitch P. This can be done very easily. Therefore, unlike the conventional one, there is no need to mechanically twist the output image with respect to the incident image, and accordingly, when adjusting the direction of the output image, mechanical twisting is required. When the image fiber was damaged, the inconvenience disappeared. Further, according to the method of manufacturing the image fiber of the present invention, the image fiber of the present invention in which the core is twisted by the desired pitch can be manufactured very easily at a low manufacturing cost.
第１図は本発明によるイメージフアイバの一実施例の外
観図、第２図はイメージファイバの製造方法の一実施例
の説明図、第３図は本発明によるイメージファイバの製
造方法の一実施例の説明図、第４図はイメージフアイバ
線引装置の断面図、第５図はイメージフアイバの横断面
図、第６図はフアイバスコープの基本構成図である。 図面中、 １はガラスフアイバ、２はジヤケツト管、 ４はコア、５はクラツド、６はジヤケツト、 ７はイメージフアイバ、８ａは対物レンズ、 ８ｂは接眼レンズ、９は観測物体、 ９ａは入射画像、９ｂは出射画像、 １０はイメージフアイバ母材、１１は線引炉、 １２はねじり母材である。FIG. 1 is an external view of an embodiment of an image fiber according to the present invention, FIG. 2 is an explanatory view of an embodiment of an image fiber manufacturing method, and FIG. 3 is an embodiment of an image fiber manufacturing method according to the present invention. 4 is a sectional view of the image fiber drawing apparatus, FIG. 5 is a transverse sectional view of the image fiber, and FIG. 6 is a basic configuration diagram of the fiber scope. In the drawings, 1 is a glass fiber, 2 is a jacket tube, 4 is a core, 5 is a cladding, 6 is a jacket, 7 is an image fiber, 8a is an objective lens, 8b is an eyepiece lens, 9 is an observation object, 9a is an incident image, 9b is an outgoing image, 10 is an image fiber base material, 11 is a drawing furnace, and 12 is a twist base material.
Claims (1)
ジャケット管の中に平行かつ稠密に配列して、加熱溶融
一体化したイメージファイバ母材を、予め加熱溶融し全
長にわたってねじりを与えて、ねじり母材を形成し、か
かるねじり母材を線引炉によって線引きすることを特徴
とするイメージファイバの製造方法。1. A plurality of glass fibers forming a core are arranged in parallel and densely in a jacket tube, and an image fiber base material integrated by heating and melting is preheated and melted and twisted over the entire length, A method for producing an image fiber, comprising forming a twisted base material and drawing the twisted base material by a drawing furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60093580A JPH0642008B2 (en) | 1985-05-02 | 1985-05-02 | Image fiber manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60093580A JPH0642008B2 (en) | 1985-05-02 | 1985-05-02 | Image fiber manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61252505A JPS61252505A (en) | 1986-11-10 |
| JPH0642008B2 true JPH0642008B2 (en) | 1994-06-01 |
Family
ID=14086205
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60093580A Expired - Lifetime JPH0642008B2 (en) | 1985-05-02 | 1985-05-02 | Image fiber manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0642008B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008505325A (en) * | 2004-07-08 | 2008-02-21 | スウィンバーン ユニバーシティ オブ テクノロジー | Fiber sensor manufacturing |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU670505B2 (en) * | 1993-06-22 | 1996-07-18 | Sumitomo Electric Industries, Ltd. | Optical fiber preform, optical fiber and their manufacturing methods |
| JP2004086028A (en) | 2002-08-28 | 2004-03-18 | Fujikura Ltd | Image fiber |
| JP4071580B2 (en) | 2002-09-02 | 2008-04-02 | 株式会社フジクラ | Image fiber processing method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5029695U (en) * | 1973-07-11 | 1975-04-03 |
-
1985
- 1985-05-02 JP JP60093580A patent/JPH0642008B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008505325A (en) * | 2004-07-08 | 2008-02-21 | スウィンバーン ユニバーシティ オブ テクノロジー | Fiber sensor manufacturing |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61252505A (en) | 1986-11-10 |
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