+

WO1991003751A1 - Raccordement par fusion des fibres optiques - Google Patents

Raccordement par fusion des fibres optiques Download PDF

Info

Publication number
WO1991003751A1
WO1991003751A1 PCT/GB1990/001390 GB9001390W WO9103751A1 WO 1991003751 A1 WO1991003751 A1 WO 1991003751A1 GB 9001390 W GB9001390 W GB 9001390W WO 9103751 A1 WO9103751 A1 WO 9103751A1
Authority
WO
WIPO (PCT)
Prior art keywords
fibre
fibre ends
temperature
contact point
fibres
Prior art date
Application number
PCT/GB1990/001390
Other languages
English (en)
Inventor
David John Clift
Stephen Robert Mallinson
Original Assignee
British Telecommunications Public Limited Company
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 British Telecommunications Public Limited Company filed Critical British Telecommunications Public Limited Company
Publication of WO1991003751A1 publication Critical patent/WO1991003751A1/fr

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
    • G02B6/2551—Splicing of light guides, e.g. by fusion or bonding using thermal methods, e.g. fusion welding by arc discharge, laser beam, plasma torch

Definitions

  • This invention relates to fusion splicing of optical fibres.
  • the radiation used is not necessarily in the visible region of the electromagnetic spectrum, and so the words 'optical' and 'light' when used in this specification are not to be interpreted as implying any limitation to the visible spectrum.
  • the wavelengths preferred for transmission through silica optical fibres are in the infra red region because the loss minima of silica fibres occurs at 1.3 and 1.5 microns.
  • Single mode optical fibre presently available has very low loss characteristics, typically less than 0.3dB/Km, and thus the losses over fibre networks are principally dependent on the jointing or splicing between fibre links, or between fibre links and fibre tails on components.
  • Fusion splicing is the most commonly used method of jointing, and can produce low loss joints, that is below O.ldB loss, but the success rate for achieving acceptable splices is low, generally 0.5dB loss being regarded as the maximum acceptable splice loss.
  • some means such as an electric arc is used to heat the ends of adjacent fibres that are to be joined together, the arc melting the fibre ends so that the two molten ends can be abutted together, adhere to one another and become permanently fused on cooling.
  • the equipment required may be complex in order to ensure, as far as possible, accurate lateral positioning and fibre movement control during the fusion process. Alignment is particularly critical with single mode fibre which has a central, comparatively small (e.g. 9 micron diameter) core along which light is propagated.
  • a typical alignment procedure comprises mounting the fibre ends that are to be joined in chucks on a splicing machine, viewing the fibre ends through a microscope, and adjusting the positions of the chucks.
  • the fibre ends become sufficiently molten that surface tension tends to pull the cladding of the fibres into exact alignment.
  • the flow of the cladding tends to deform the cores (the ends of the cores becoming asymmetrically located in the cladding).
  • One technique that has been used for improving splices is to taper the fused splice, for example as reported in 'Low-loss joints between dissimilar fibres by tapering fusion splices', in Electronics Letters, 13 March 1986, Vol. 22 No. 6 pp 318-319.
  • the tapering of a splice between single mode fibres results in a tapering of the core, and a reduction in the core diameter increases the mode field spot size.
  • With an increased mode field spot size light becomes guided by the cladding in the region of the splice and then subsequently returns to being guided by the core as the spot size reduces again on the far side of the tapered splice.
  • the aim of the invention is to provide low loss fusion splices with less stringent selection criteria for the fibre ends.
  • the present invention provides a method of fusion splicing optical fibre ends, the method comprising the steps of heating the fibre ends to a first temperature that is sufficient to cause surface melting but insufficient to permit substantial flow of fibre material, advancing the fibre ends towards one another thereby ensuring the fibre ends adhere to one another at an initial contact point, advancing the fibre ends beyond the initial contact point so that any end angles on the fibres induce lateral fibre deflection to bring the fibre end faces into substantial contact, and subsequently heating the fibre ends to a second temperature ard pulling the joint formed between the fibre ends to remove any bend at the joint, the second temperature being higher than the first temperature.
  • the distance that the fibre ends are advanced beyond the initial contact point is substantially equal to the distance through which the fibre joint is subsequently pulled.
  • the distance that the fibre ends are advanced beyond the initial contact point is in the range of from 5 to 20 microns.
  • the fibre ends are heated to a temperature intermediate to the first and second temperatures.
  • the heating is by an electric arc.
  • an electric current of 7 to 11mA is applied to the electric arc to heat the fibre ends to said first temperature, and the fibre ends are advanced towards one another at a speed of 200 «m per second.
  • an electric current of 13 to 17mA is applied to the electric arc to heat the fibre ends to said second temperature, and an electric current of 10 to 13mA is applied to the electric arc to heat the fibre ends to said intermediate temperature.
  • the joint may be pulled at 10 ⁇ m per second.
  • the fibre ends are advanced beyond the initial contact point after a predetermined time interval following contact of the fibre ends at the initial contact point.
  • the predetermined time interval may be 2 seconds.
  • Figure 1 is a schematic diagram of two monomode fibres prepared for splicing, one fibre having an end angle;
  • Figure 2 is a schematic diagram of the fibres of Figure 1 joined by a prior art fusion splicing method
  • Figure 3 is a schematic diagram of two monomode fibres mounted for splicing in a fusion splicing machine;
  • Figure 4 is a schematic diagram of the fibres of Figure 3 at the end of the tacking stage in a procec 5 " , ⁇ e according to the present invention.
  • Figure 5 is a schematic diagram of the fibres af .r completion of the pulling stage of a procedure according to the present invention.
  • Figure 1 shows a first single mode fibre 1 having a core 2, cladding 3 and an end face 4 normal to the longitudinal axis of the fibre.
  • a second fibre 5, having a core 6 and cladding 7, has an end face 8 at an angle (exaggerated in the drawing) which may typically deviate by up to 8 * from the plane normal to the longitudinal axis of the fibre.
  • the ends of the fibres 1 and 5 would be heated in an arc discharge; typically, for an electrode spacing of 2.3 mm in a splicer such as an Ericsson FSU850 fusion splicer, at a current of the order of 10 milliamps prior to contact of the fibre end faces 4 and 8. Upon contact, the current would be increased to the order of 15 or 16 milliamps.
  • a splicer such as an Ericsson FSU850 fusion splicer
  • the first (10mA) heating stage starts with the fibres 1 and 5 separated by a gap of about 50 microns, and heating to the higher level starts as soon as the end faces 4 and 8 come into contact, the then relatively molten ends being squashed together for a further distance of travel of about 5 microns.
  • the heating is then maintained at a slightly lower level (12mA) for a period of about two seconds.
  • the arc is switched off, and the fused splice cools.
  • Figure 2 for fibre ends of the type shown in Figure 1.
  • a gap 9 see Figure 1 which is filled by flow of molten cladding material. This flow of molten cladding material drags the cores 2 and 6 with it, so that the cores are angularly offset, thereby resulting in high loss due to phase mismatch.
  • the principle of the present invention is to use a lower heating current and a push-pull technique in which the two ends to be spliced are pushed against one another to achieve substantially planar sticking contact, and then subsequently pulled back. Owing to the use of a lower heating current, only the surfaces of the fibres melt, and flow into any gap between the fibres is inhibited. The process will now be described in more detail with reference to Figures 3 to 5.
  • Two fibres 1' and 5' to be spliced together are located in the chucks (not shown) of a fusion splicer, as schematically shown in Figure 3.
  • the ends of the fibres 1' and 5' are selected for their relatively poor quality, having significant end angles so that one or both end faces provided an included end angle in the range of 2 * to 8".
  • the fibres 1' and 5* are separated by an arbitrary distance; but, for the start of the splicing procedure, they are brought into contact with one another to establish the contact point datum.
  • the fibre ends will meet as shown in Figure 1 (in the case of only one poor end angle).
  • the fibre ends are aligned by the usual viewing techniques on fusion splicing machines, and the chucks are then separated to starting positions which may be, for example, a separation of about 80 microns. From the starting positions, the ends are then moved towards one another by movement of one or both chucks; and, at a separation of 50 microns, a low arc current is turned on.
  • an arc current of 7 to 11 mA is used. It has been found satisfactory to move the fibres 1' and 5' towards one another at a rate of 200 microns per second.
  • the movement is programmed so that the fibre ends first touch (at the previously establis h ed contact point datum), and are then pushed in on each -her by a distance of 5 to 20 microns.
  • the fibres 1' and 5' have molten surfaces that adhere to one another, but the underlying fibres are not molten and so are unyielding.
  • the fibres 1' and 5' deflects, so that the fibre end faces come into substantially planar contact, with the fibres at an angle as shown in Figure 3.
  • the fibres 1' and 5' are essentially tacked together by the contact of the molten surfaces.
  • the chucks are held stationary for about two seconds.
  • the arc current is then increased to about 10 to 13 mA to create additional melting to fuse the fibre ends together in the tacked position. Since the ends of the fibres 1* and 5' have been tacked together with the full surfaces of the fibre ends substantially in contact, there is no gap for cladding to flow into and induce deformation of the cores. It should also be noted that this increased temperature stage is at a lower temperature than the second stage of the prior art process, and also takes place after the fibres 1' and 5' are stationary, so that the more molten fibre is not pushed and deformed.
  • the current is again increased (to a range of 13 to 17 mA), and the chucks are moved apart in an outward stroke by approxima- y the same distance as the fibre ends were moved inwards beyond the contact point datum.
  • the chucks may be moved apart at any suitable speed, but it has been found that a speed of 10 microns per second for the relatively small distance of travel required is satisfactory.
  • Figure 5 shows schematically the fibre splice region at the end of the outward pulling stroke.
  • the kink in the spliced fibre is straightened, with the result that the fibres 1' and 5' and the cores 2' and 6' are both aligned and straight.
  • the distance through which the fibre ends are pushed together beyond the contact point datum depends upon the end angle(s) to be spliced. For example, small end angles of about 2' need only about 4 to 5 microns of additional travel to make the ends abut as shown in Figure 4, whereas larger end angles require a greater travel distance. It has been found that end angles of up to 8 * can be satisfactorily spliced using the method of the invention with an additional travel distance of about 20 microns. If it is desired to cope with a range of end angles, the travel distance is set to correspond to that of the largest end angle to be spliced.
  • the fibres When smaller end angles are subjected to the additional travel the fibres will either bend elastically or slide back in the chucks. There may be end angles on one or both of the fibre ends. In some instances, if both fibre ends have angles the angles may align in a complementary way, so that planar contact is achieved without substantial flexing or deviation of the fibres. In such a case, the fibres are treated as if the ends had no end angles. At other times, the end angles may both tend to leave a gap at the same place. Preferably the maximum included angle between fibre ends is 8 * .

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Mechanical Coupling Of Light Guides (AREA)

Abstract

Procédé de raccordement par fusion des extrêmités de fibres optiques dans lequel les extrêmités des fibres sont chauffées jusqu'à une température suffisante pour les permettre des se coller l'une à l'autre mais insuffisante pour permettre un flux sensible. Les fibres (1' et 5') sont ensuite rapprochées et avancées au-delà d'un point de contact initial, de sorte que tout angle terminal sur les fibres provoque une déflexion latérale de la (des) fibre(s) afin d'amener les faces terminales vers un contact sensiblement planaire. Le chauffage est ensuite augmenté afin de porter le joint en fibre à fusion, puis une étape supplémentaire de chauffage et de tirage enlève toute courbure au niveau du joint.
PCT/GB1990/001390 1989-09-11 1990-09-07 Raccordement par fusion des fibres optiques WO1991003751A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB898920473A GB8920473D0 (en) 1989-09-11 1989-09-11 Optical fibre fusion splicing
GB8920473.9 1989-09-11

Publications (1)

Publication Number Publication Date
WO1991003751A1 true WO1991003751A1 (fr) 1991-03-21

Family

ID=10662862

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1990/001390 WO1991003751A1 (fr) 1989-09-11 1990-09-07 Raccordement par fusion des fibres optiques

Country Status (3)

Country Link
AU (1) AU6335490A (fr)
GB (1) GB8920473D0 (fr)
WO (1) WO1991003751A1 (fr)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2271433A (en) * 1992-10-08 1994-04-13 David Lister Myers Optical fibre fusion splicing with reciprocal movement
EP0594996A2 (fr) * 1992-10-30 1994-05-04 Siemens Aktiengesellschaft Atténuateur optique, méthode pour sa fabrication et appareil adapté pour l'épissage par fusion
GB2272306A (en) * 1992-11-09 1994-05-11 Fujitsu Ltd Coupling optical waveguides by fusion or photosensitive monomer-polymer compositions
WO1995023990A1 (fr) * 1994-03-03 1995-09-08 Fiberlign Division Of Preformed Line Products (Canada) Ltd. Procede et appareil de gestion du contact de fibres optiques
EP0687928A1 (fr) * 1994-06-16 1995-12-20 Telefonaktiebolaget Lm Ericsson Connexion des fibres optiques
US5902715A (en) * 1992-11-09 1999-05-11 Fujitsu Limited Method of forming a mirror in a waveguide
EP1385029A1 (fr) * 2001-03-23 2004-01-28 Sumitomo Electric Industries, Ltd. Procédé d'épisser par fusion de fibres optiques

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61143704A (ja) * 1984-12-17 1986-07-01 Fujikura Ltd 単一モ−ド光フアイバの融着接続方法
EP0321947A2 (fr) * 1987-12-21 1989-06-28 Fujikura Ltd. Procédé pour tester la partie soudée de fibres optiques

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61143704A (ja) * 1984-12-17 1986-07-01 Fujikura Ltd 単一モ−ド光フアイバの融着接続方法
EP0321947A2 (fr) * 1987-12-21 1989-06-28 Fujikura Ltd. Procédé pour tester la partie soudée de fibres optiques

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Electronics and Communications in Japan, Volume 65, No. 2, February 1982, Silver Spring, (Maryland, US), M. MIYAUCHI et al.: "Arc-Fusion Splice of Multimode Optical Fibers using Prefusion Method", pages 61-70 see figures 1,2,9,14; sections 3.1, 4.1 *
Journal of Optical Communications, Volume 10, No. 2, June 1986, (Berlin, DE) A. ISHIKURA et al.: "Mass Splice Method for Single-Mode Fiber Ribbons", pages 61-66 see figure 5; page 63, lines 10-31 *
PATENT ABSTRACTS OF JAPAN, Volume 10, No. 341 (P-517) (2397), 18 November 1986, & JP, A, 61143704 (Fujikura Ltd) 1 July 1986 see whole document *

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2271433A (en) * 1992-10-08 1994-04-13 David Lister Myers Optical fibre fusion splicing with reciprocal movement
EP0594996A3 (en) * 1992-10-30 1994-07-13 Siemens Ag Optical attenuator, method of its production and adapted fusion splicing machine
EP0594996A2 (fr) * 1992-10-30 1994-05-04 Siemens Aktiengesellschaft Atténuateur optique, méthode pour sa fabrication et appareil adapté pour l'épissage par fusion
US5902715A (en) * 1992-11-09 1999-05-11 Fujitsu Limited Method of forming a mirror in a waveguide
GB2272306B (en) * 1992-11-09 1996-11-20 Fujitsu Ltd Coupling of optical parts using a refractive index imaging material
US5581646A (en) * 1992-11-09 1996-12-03 Fujitsu Limited Method of coupling optical parts and refractive index imaging material
US5658966A (en) * 1992-11-09 1997-08-19 Fujitsu Limited Method of coupling optical parts and refractive index imaging material
US5861444A (en) * 1992-11-09 1999-01-19 Fujitsu Limited Refractive index imaging material
GB2272306A (en) * 1992-11-09 1994-05-11 Fujitsu Ltd Coupling optical waveguides by fusion or photosensitive monomer-polymer compositions
US6017681A (en) * 1992-11-09 2000-01-25 Fujitsu Limited Method of coupling optical parts and method of forming a mirror
WO1995023990A1 (fr) * 1994-03-03 1995-09-08 Fiberlign Division Of Preformed Line Products (Canada) Ltd. Procede et appareil de gestion du contact de fibres optiques
US5596672A (en) * 1994-03-03 1997-01-21 Fiberlign Division Of Preformed Line Products (Canada) Ltd. Method and apparatus for controlling the contact of optical fibers
EP0687928A1 (fr) * 1994-06-16 1995-12-20 Telefonaktiebolaget Lm Ericsson Connexion des fibres optiques
US5570446A (en) * 1994-06-16 1996-10-29 Telefoanaktiebolaget Lm Ericsson Alignment and control in splicing optical fibers
EP1385029A1 (fr) * 2001-03-23 2004-01-28 Sumitomo Electric Industries, Ltd. Procédé d'épisser par fusion de fibres optiques
US6835005B2 (en) 2001-03-23 2004-12-28 Sumitomo Electric Industries, Ltd. Method for fusion splicing optical fibers

Also Published As

Publication number Publication date
GB8920473D0 (en) 1989-10-25
AU6335490A (en) 1991-04-08

Similar Documents

Publication Publication Date Title
EP0144136B1 (fr) Procédé de fabrication d'un atténuateur optiqe par raccordement par fusion de fibres optiques
EP0235992B1 (fr) Méthode pour réduire les pertes dans une connexion de fibres optiques
US5588087A (en) Overlapping fusion attenuator
US4049414A (en) Method and apparatus for splicing optical fibers
US5142603A (en) Method of connecting high numerical aperture optical waveguides
US4589897A (en) Method for the manufacturing of a fiber with a tapered end having a refractive lens
US20020164132A1 (en) Method and apparatus for splicing optical fibers
CA2011561A1 (fr) Appareil et methode pour realiser des epissures de fibres optiques, permanentes et a faibles pertes
WO1991003751A1 (fr) Raccordement par fusion des fibres optiques
US4820321A (en) Method and apparatus for fabricating an expanded beam cylindrically terminated optical fiber taper
JP2503138B2 (ja) 光ファイバ用端子
JP5416721B2 (ja) 光ファイバ端部加工方法および光ファイバ端部加工装置
US20030108307A1 (en) Optical attenuator employing a fusion splice
EP0623831A1 (fr) Méthode et dispositif pour épisser par fusion des fibres optiques
GB2185127A (en) Fusion splicing optical fibres
JP3607642B2 (ja) 光ファイバの融着接続機
JPH07294770A (ja) 石英系導波路と光ファイバとの接続方法および接続部構造
JPH02251916A (ja) 石英系光導波回路と光ファイバの接続方法
JPS6016884Y2 (ja) 光フアイバ融着接続装置
JPH05142442A (ja) 光フアイバの融着接続方法
JPH04184401A (ja) 光ファイバの融着接続方法
JPH07140344A (ja) プラスチック光ファイバの融着接続装置
JP2003029078A (ja) 一括融着接続方法と一括融着接続装置
JPS5926928B2 (ja) シングルモ−ド伝送型光フアイバの融着接続方法
JPS63168606A (ja) 光フアイバ接続方法

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU CA JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB IT LU NL SE

NENP Non-entry into the national phase

Ref country code: CA

点击 这是indexloc提供的php浏览器服务，不要输入任何密码和下载