DE3516899A1 - Method for manufacturing a fibre optical waveguide connection - Google Patents

Method for manufacturing a fibre optical waveguide connection

Info

Publication number
DE3516899A1
DE3516899A1 DE19853516899 DE3516899A DE3516899A1 DE 3516899 A1 DE3516899 A1 DE 3516899A1 DE 19853516899 DE19853516899 DE 19853516899 DE 3516899 A DE3516899 A DE 3516899A DE 3516899 A1 DE3516899 A1 DE 3516899A1
Authority
DE
Germany
Prior art keywords
fiber
core
fibre
cladding
away
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.)
Granted
Application number
DE19853516899
Other languages
German (de)
Other versions
DE3516899C2 (en
Inventor
Bernhard Dr.-Ing. 7153 Weissach Schwaderer
Thomas Dipl.-Ing. 7150 Backnang Schwander
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bosch Telecom GmbH
Original Assignee
ANT Nachrichtentechnik GmbH
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by ANT Nachrichtentechnik GmbH filed Critical ANT Nachrichtentechnik GmbH
Priority to DE19853516899 priority Critical patent/DE3516899A1/en
Publication of DE3516899A1 publication Critical patent/DE3516899A1/en
Application granted granted Critical
Publication of DE3516899C2 publication Critical patent/DE3516899C2/de
Granted legal-status Critical Current

Links

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
    • G02B6/2555—Alignment or adjustment devices for aligning prior to splicing
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C15/00—Surface treatment of glass, not in the form of fibres or filaments, by etching
    • 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
    • G02B6/245—Removing protective coverings of light guides before coupling
    • 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
    • G02B6/2551—Splicing of light guides, e.g. by fusion or bonding using thermal methods, e.g. fusion welding by arc discharge, laser beam, plasma torch
    • 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
    • G02B6/26—Optical coupling means
    • G02B6/262—Optical details of coupling light into, or out of, or between fibre ends, e.g. special fibre end shapes or associated optical elements
    • 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
    • G02B6/36—Mechanical coupling means
    • G02B6/38—Mechanical coupling means having fibre to fibre mating means
    • G02B6/3801—Permanent connections, i.e. wherein fibres are kept aligned by mechanical means
    • G02B6/3803—Adjustment or alignment devices for alignment prior to splicing
    • 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
    • G02B6/36—Mechanical coupling means
    • G02B6/38—Mechanical coupling means having fibre to fibre mating means
    • G02B6/3801—Permanent connections, i.e. wherein fibres are kept aligned by mechanical means
    • G02B6/3806—Semi-permanent connections, i.e. wherein the mechanical means keeping the fibres aligned allow for removal of the fibres
    • 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
    • G02B6/36—Mechanical coupling means
    • G02B6/38—Mechanical coupling means having fibre to fibre mating means
    • G02B6/3807—Dismountable connectors, i.e. comprising plugs
    • G02B6/3833—Details of mounting fibres in ferrules; Assembly methods; Manufacture
    • G02B6/3834—Means for centering or aligning the light guide within the ferrule
    • 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
    • G02B6/36—Mechanical coupling means
    • G02B6/38—Mechanical coupling means having fibre to fibre mating means
    • G02B6/3807—Dismountable connectors, i.e. comprising plugs
    • G02B6/3833—Details of mounting fibres in ferrules; Assembly methods; Manufacture
    • G02B6/3834—Means for centering or aligning the light guide within the ferrule
    • G02B6/3838—Means for centering or aligning the light guide within the ferrule using grooves for light guides

Abstract

An uncomplicated method for producing a low-loss fibre optical waveguide connection consists in the one fibre end (1) being dipped into an etching agent which etches away the core material (3) but does not attack the material of the outer fibre sheath (6), in that the other fibre end (2) is dipped into another etching agent which etches away the material of the outer fibre sheath (8) but does not attack the core material (4), and in that the fibre core component (4), which protrudes with respect to the fibre sheath (8), of the other optical waveguide fibre (2) is then plugged into the fibre sheath, which protrudes with respect to the fibre core (3), of the one optical waveguide fibre (1). <IMAGE>

Description

Verfahren zum Herstellen einer Lichtleitfaserverbindung Method of making an optical fiber connection

Die vorliegende Erfindung betrifft ein Verfahren zum Herstellen einer Lichtleitfaserverbindung, bei der die Faserkerne sich selbst beim Zusammenführen der Lichtleitfasern stirnseitig zueinander ausrichten.The present invention relates to a method of making a Optical fiber connection in which the fiber cores self-assemble when they are brought together Align the optical fibers with one another at the front.

Ein übliches, z.B. aus der DE 33 32 731 Al bekanntes Verfahren zur Herstellung einer Lichtleitfaserverbindung besteht darin, daß die zwei miteinander zu koppelnden Faserenden vom äußeren Schutzmantel befreit und dann in eine an den Faserdurchmesser angepaßte Bohrung einer Aufnahmehülse hineingesteckt werden, worin sie mit ihren plan polierten Stirnseiten zusammentreffen. Hierbei entsteht aber nur dann eine dämpfungsarme Verbindung, wenn die lichtführenden Kerne der Fasern äußerst zentrisch in ihren Fasermänteln liegen.A common, e.g. known from DE 33 32 731 A1 method for Making a fiber optic connection consists in letting the two connect to each other to be coupled fiber ends freed from the outer protective sheath and then in one to the Fiber diameter adapted bore of a receiving sleeve are inserted, in which they meet with their flat polished end faces. Here, however, arises only a low-attenuation connection if the light-guiding cores of the fibers are extremely centric in their fiber sheaths.

Diese Voraussetzung ist jedoch bei sehr dünnen Monomodefasern in der Regel nur unzureichend erfüllt. Schon ein gegenseitiger axialer Versatz der beiden zu koppelnden Monomodefaserkerne von mehr als 1 um führt zu einer nicht tragbaren Dämpfung, weil nämlich die Faserkerne einen sehr geringen Durchmesser (ca. 10 ,um) aufweisen.However, this requirement is in the case of very thin single-mode fibers Usually insufficiently fulfilled. Already a mutual axial misalignment of the two Single-mode fiber cores of more than 1 μm to be coupled leads to a non-portable Attenuation, because the fiber cores have a very small diameter (approx. 10 μm) exhibit.

Der Erfindung liegt nun die Aufgabe zugrunde, ein Verfahren zur Herstellung einer Lichtleitfaserverbindung anzugeben, das mit sehr geringem Aufwand durchführbar ist und selbst für Monomodefasern mit sehr kleinem Kerndurchmesser eine dämpfungsarme Verbindung liefert.The invention is now based on the object of a method for production specify an optical fiber connection that can be carried out with very little effort is low-attenuation and even for single-mode fibers with a very small core diameter Connection supplies.

Erfindungsgemäß wird diese Aufgabe dadurch gelöst, daß das eine Faserende in ein Ätzmittel getaucht wird, welches das Kernmaterial gegenüber dem Material des äußeren Fasermantels aber nicht wegätzt, daß das andere Faserende in ein anderes Ätzmittel getaucht wird, welches das Material des äußeren Fasermantels gegenüber dem Kernmaterial wegätzt, und daß dann in den nach dem Wegätzen des Kernmaterials gegenüber dem Faserkern hervorstehenden Fasermantel der einen Lichtleitfaser das nach dem Wegätzen des Mantelmaterials gegenüber dem Fasermantel hervorstehende Faserkernteil der anderen Lichtleitfaser hineingesteckt wird.According to the invention this object is achieved in that one fiber end is immersed in an etchant, which the core material against the material of the outer fiber cladding does not etch away that the other fiber end into another Etchant is immersed, which is the material of the outer fiber sheath with respect to the core material etched away, and that then in the after the core material has been etched away opposite the fiber core protruding fiber cladding of one optical fiber that after the cladding material has been etched away, the fiber core part protrudes from the fiber cladding the other optical fiber is inserted.

Zweckmäßige Ausführungen der Erfindung gehen aus den Unteransprüchen hervor.Appropriate embodiments of the invention are based on the subclaims emerged.

Es ist ein Vorteil der Erfindung, daß sich die Faserkerne beim Zusammenstecken der Lichtleitfaserenden von selbst exakt zueinander ausrichten, ohne daß zusätzliche Justiermaßnahmen erforderlich sind.It is an advantage of the invention that the fiber cores when plugged together align the optical fiber ends exactly to each other by themselves without additional Adjustment measures are required.

Anhand eines in der Zeichnung dargestellten Ausführungsbeispiels wird nachfolgend die Erfindung näher erläutert.Based on an embodiment shown in the drawing the invention is explained in more detail below.

Wie die Figur verdeutlicht, handelt es sich bei diesem Ausführungsbeispiel um zwei miteinander zu koppelnde Lichtleitfasern 1 und 2, deren Kern 3 bzw. 4 jeweils von einem zweischichtigen Mantel umgeben ist. Der Brechzahlverlauf n der beiden Fasern 1 und 2 zeigt, daß der Kern 3 bzw. 4 einen größeren Brechungsindex als die beiden Fasermäntel 5,6 bzw.As the figure shows, it is in this embodiment around two optical fibers 1 and 2 to be coupled with one another, their core 3 and 4 respectively is surrounded by a two-layer coat. The refractive index curve n of the two Fibers 1 and 2 shows that the core 3 and 4, respectively, have a larger refractive index than that both fiber sheaths 5,6 resp.

7,8 und der den Kern 3 bzw. 4 umgebende innere Mantel 5 bzw. 7 einen kleineren Brechungsindex als der äußere Mantel 6 bzw. 8 aufweist. Das anschließend beschriebene Verfahren zur Herstellung einer Lichtleitfaserverbindung ist nicht auf solche Fasern mit zweischichtigen Mänteln und dem angegebenen Brechzahlprofil beschränkt. Es kann auch auf beliebige andere Fasern angewendet werden.7, 8 and the inner jacket 5 and 7 surrounding the core 3 and 4, respectively has a smaller refractive index than the outer cladding 6 and 8, respectively. That afterwards described method for establishing an optical fiber connection is not on such fibers with two-layer cladding and the specified refractive index profile limited. It can also be applied to any other fiber.

Eine Faser 1 wird in ein Atzmittel eingetaucht, welches vornehmlich das Material des Kerns 3 wegätzt, den äußeren Mantel 6 aber nicht angreift. Dagegen wird die andere Faser 2 in ein anderes Ätzmittel eingetaucht, welches vornehmlich das Material des äußeren Mantels 8 wegätzt, aber den Kern 4 stehen läßt.A fiber 1 is immersed in an etchant, which primarily etches away the material of the core 3, but does not attack the outer cladding 6. Against it becomes the other fiber 2 immersed in another etchant, which primarily the material of the outer jacket 8 is etched away, but the core 4 is left standing.

Bei diesen Ätzvorgängen werden auch Materialteile des inneren Mantels 5 bzw. 7 abgetragen, so daß ein konischer übergang vom Kern 3 bzw. 4 auf den äußeren Mantel 6 bzw. 8 entsteht. Beide Fasern werden dem Ätzprozeß solange ausgesetzt, bis bei der einen Faser 1 der Kern 3 gegenüber dem äußeren Mantel 6 um die gleiche Länge (z.B. 20 pm) zurückgeätzt ist wie bei der anderen Faser 2 der äußere Mantel 8 gegenüber dem Kern 4.During these etching processes, material parts of the inner jacket are also formed 5 or 7 removed, so that a conical transition from the core 3 or 4 to the outer Shell 6 or 8 is created. Both fibers are exposed to the etching process as long as until the core 3 of one fiber 1 is the same as that of the outer cladding 6 Length (e.g. 20 pm) is etched back, as with the other fiber 2, the outer cladding 8 opposite the core 4.

Zum Wegätzen des Kernmaterials, welches aus Ge-dotiertem Quarzglas besteht, wird als Ätzmittel Schwefelsäure verwendet und zum Wegätzen des äußeren Mantels, welcher aus reinem Quarzglas besteht, wird als Ätzmittel gepufferte Flußsäure verwendet. Der innere Fasermantel 5 bzw. 7 setzt sich aus F-dotiertem Quarzglas zusammen.For etching away the core material, which is made of Ge-doped quartz glass consists, sulfuric acid is used as an etchant and to etch away the outer Mantle, which consists of pure quartz glass, is used as an etchant with buffered hydrofluoric acid used. The inner fiber cladding 5 or 7 is made of F-doped quartz glass together.

Nach abgeschlossenem Ätzvorgang werden beide Faserenden 1 und 2 ineinandergesteckt, so daß der vorstehende Kernteil der einen Faser 2 in den vorstehenden Mantelteil der anderen Faser 1 eingreift. Dabei ist gewährleistet, daß die Kerne 3 und 4 der beiden Fasern 1 und 2 stirnseitig nahezu ohne axialen Versatz zusammentreffen, unabhängig von der exzentrischen Lage der Kerne in den Fasern. Danach werden die Faserenden unlösbar miteinander verschweißt oder lösbar in einem Steckergehäuse festgeklemmt.After the etching process is complete, both fiber ends 1 and 2 are plugged into one another, so that the protruding core part of one fiber 2 in the protruding cladding part the other fiber 1 engages. It is ensured that the cores 3 and 4 of the both fibers 1 and 2 meet at the front with almost no axial offset, independently on the eccentric position of the nuclei in the fibers. After that the fiber ends permanently welded together or releasably clamped in a connector housing.

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Claims (4)

Patentansprüche: 1. Verfahren zum Herstellen einer Lichtleitfaserverbindung, bei der die Faserkerne sich selbst beim Zusammenführen der Lichtleitfasern stirnseitig zueinander ausrichten, dadurch t gekennzeichnet, daß das eine Faserende (1) in ein Ätzmittel getaucht wird, welches das Kernmaterial (3) gegenüber dem Material des äußeren Fasermantels (6) wegätzt, daß das andere Faserende (2) in ein anderes Atzmittel getaucht wird, welches das Material des äußeren Fasermantels (8) gegenüber dem Kernmaterial (4) nicht - wegätzt, und daß dann in den nach dem Wegätzen des Kernmaterials gegenüber dem Faserkern (3) hervorstehenden Fasermantel (6) der einen Lichtleitfaser (1) das nach dem Wegätzen des Mantelmaterials gegenüber dem Fasermantel (8) hervorstehende Faserkernteil (4) der anderen Lichtleitfaser (2) hineingesteckt wird.Claims: 1. Method for establishing an optical fiber connection, in which the fiber cores themselves when the optical fibers are brought together at the end align to each other, characterized in that the one fiber end (1) in a Etchant is dipped, which the core material (3) against the material of the outer fiber sheath (6) etches away that the other fiber end (2) in another etching agent is immersed, which is the material of the outer fiber cladding (8) compared to the core material (4) not - etched away, and that then in the opposite direction after etching away the core material the fiber core (3) protruding fiber cladding (6) of one optical fiber (1) the protruding after the cladding material has been etched away from the fiber cladding (8) Fiber core part (4) of the other optical fiber (2) is inserted. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß bei der einen Lichtleitfaser (1) der Kern (3) auf die gleiche Länge weggeätzt wird wie bei der anderen Lichtleitfaser (2) der äußere Fasermantel (8).2. The method according to claim 1, characterized in that in the an optical fiber (1) the core (3) is etched away to the same length as in the other optical fiber (2) the outer fiber cladding (8). 3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß für das Wegätzen des Kernmaterials, bestehend aus Gedotiertem Quarzglas, als Ätzmittel Schwefelsäure verwendet wird, 3. The method according to claim 1, characterized in that for the Etching away the core material, consisting of doped quartz glass, as etching agent sulfuric acid is used, 4. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß für das Wegätzen des Mantelmaterials, bestehend aus reinem bzw. F-dotiertem Quarzglas, als Ätzmittel gepufferte Flußsäure verwendet wird.4. The method according to claim 1, characterized in that for the Etching away the cladding material, consisting of pure or F-doped quartz glass, as Etchant buffered hydrofluoric acid is used.
DE19853516899 1985-05-10 1985-05-10 Method for manufacturing a fibre optical waveguide connection Granted DE3516899A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19853516899 DE3516899A1 (en) 1985-05-10 1985-05-10 Method for manufacturing a fibre optical waveguide connection

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19853516899 DE3516899A1 (en) 1985-05-10 1985-05-10 Method for manufacturing a fibre optical waveguide connection

Publications (2)

Publication Number Publication Date
DE3516899A1 true DE3516899A1 (en) 1986-11-13
DE3516899C2 DE3516899C2 (en) 1987-02-26

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DE19853516899 Granted DE3516899A1 (en) 1985-05-10 1985-05-10 Method for manufacturing a fibre optical waveguide connection

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU590784B2 (en) * 1985-08-15 1989-11-16 Corning Glass Works Optical fiber device interconnection and method
EP0400377A2 (en) * 1989-05-31 1990-12-05 The Whitaker Corporation Construction of an optical fiber with a connector
EP0444809A1 (en) * 1990-02-28 1991-09-04 AT&T Corp. Matte finishes on optical fibers and other glass articles
EP0650081A1 (en) * 1993-10-21 1995-04-26 Röhm GmbH Connection elements for light guiding members
WO2002097495A1 (en) * 2001-05-31 2002-12-05 The University Of Sydney A method of splicing waveguides

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
NICHTS-ERMITTELT *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU590784B2 (en) * 1985-08-15 1989-11-16 Corning Glass Works Optical fiber device interconnection and method
EP0400377A2 (en) * 1989-05-31 1990-12-05 The Whitaker Corporation Construction of an optical fiber with a connector
EP0400377A3 (en) * 1989-05-31 1991-10-23 The Whitaker Corporation Construction of an optical fiber with a connector
EP0444809A1 (en) * 1990-02-28 1991-09-04 AT&T Corp. Matte finishes on optical fibers and other glass articles
US5091053A (en) * 1990-02-28 1992-02-25 At&T Bell Laboratories Matte finishes on optical fibers and other glass articles
US5448672A (en) * 1990-02-28 1995-09-05 At&T Corp. Optical fibers with matte finishes
EP0650081A1 (en) * 1993-10-21 1995-04-26 Röhm GmbH Connection elements for light guiding members
WO2002097495A1 (en) * 2001-05-31 2002-12-05 The University Of Sydney A method of splicing waveguides

Also Published As

Publication number Publication date
DE3516899C2 (en) 1987-02-26

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