WO2011006248A1

WO2011006248A1 - Optical fiber connector having shouldered slot and method and apparatus for actuating connector

Info

Publication number: WO2011006248A1
Application number: PCT/CA2010/001099
Authority: WO
Inventors: Alex Fraser; Eric Weynant; Patrick Zivojinovic
Original assignee: Phasoptx Inc.
Priority date: 2009-07-13
Filing date: 2010-07-13
Publication date: 2011-01-20

Abstract

An optical fiber connector for connecting the ends of two optical fibers has a connector body made of a highly elastic material. The connector body has end faces and a lateral outer surface. A fiber conduit extends along a longitudinal axis of the connector body. The conduit is adapted to receive one or more optical fibers. The connector includes a shouldered fiber slot extending longitudinally between end faces of the connector body. The shouldered slot has a narrow portion extending radially outwardly from the fiber conduit and a wide portion extending radially inwardly from the outer surface. The wide portion of the shouldered slot has inwardly facing surfaces upon which opposing lateral forces can be applied for causing the shouldered slot to expand for receiving the optical fibers. The lateral opposing forces can be applied orthogonally to a radial direction defined by the shouldered slot.

Description

OPTICAL FIBER CONNECTOR HAVING SHOULDERED SLOT AND METHOD AND APPARATUS FOR ACTUATING CONNECTOR

TECHNICAL FIELD The present invention relates generally to an optical fiber connector and, in particular, to an optical fiber connector made of a highly elastic material such as a shape memory alloy.

BACKGROUND Optical communications systems, which provide the backbone of most modern long- haul telecommunications networks, use fiber optic cables to carry the optical signals from one node to another. Efficiently connecting fiber optic cables together remains a technical problem for which a fully satisfactory solution has yet to have been devised. Two general optical fiber splicing techniques are known in the art, arc fusion splicing and mechanical splicing. Arc fusion splicing is accomplished by fusing the ends of optical fibers together with a spark generated by electrodes. This technique tends to be intricate and time-consuming to utilize. Mechanical splicing is a much quicker technique but it has a propensity to incur high optical losses (insertion losses) across the connection or coupling due to the bonded joint. Mechanically splicing fibers typically requires that the fibers be aligned and held together using a precision sleeve and gel adhesive having a carefully selected index of refraction that minimizes Fresnel reflection across the splice. Nonetheless, these mechanical splices typically have higher optical losses and are less robust than fusion splices, even if a protective enclosure is used.

In the case of mechanical connectors, it is common to place the fiber ends in a single "V" groove on a substrate in end-to-end abutment and then to build a packaging around the fibers with the use of optical gels and/or adhesives to complete the connection. When the fibers are not of the same diameter, it is challenging to align the fibers.

The use of glue or bonding agent (distinct from an index-matching gel) to bond the mechanical splices together is problematic because the bond may come undone, especially in the presence of thermal extremes (i.e. may melt or loosen in extreme heat or become brittle in extreme cold). For many applications, therefore, a bonded connection is unsatisfactory. Furthermore, a bonded connection cannot be rotated inside the connector, i.e. one cable cannot be rotated relative to the other cable. For applications where the polarization of light matters, a bonded mechanical splice can be highly inflexible. Moreover, another significant disadvantage of bonded couplings is that they cannot be reused.

Various techniques for mechanically splicing optical fibers are described in U.S. Patent 7,066,656; U.S. Patent 7,121 ,731 , PCT/CA2004/001855 (WO 2005/040876), and PCT/CA2008/001147 (WO 2008/151445) which are all incorporated by reference herein. The connectors and methods described in these documents exploit shape memory materials, such as shape memory alloys, to provide useful mechanical connections.

In one implementation of the shape memory mechanical splices, as disclosed in WO 2008/151445, a wedging force is applied into a fiber slot to expand the fiber conduit.

This wedging force, however, can cause rotation of the connector if the wedging force and connector are not perfectly aligned. Moreover, the distance between the top surface of the connector and the fiber conduit changes when applying the wedging force, thus requiring adjustment or re-calibration of the apparatus used to align the splices with the fibers for subsequent usage.

Therefore, improvements on this mechanical splicing technology remain highly desirable in order to overcome one or more of these technical problems. SUMMARY

A novel optical fiber connector has a shouldered slot. The shouldered slot, or "stepped" slot, has a narrow portion and a wide portion. Separators act transversely on inner wails of the wide portion of the shouldered slot to exert equal and opposite forces to further separate the inner walls of the shouldered slot. The transverse forces acting on the inner wails of the shouldered slot cause the fiber conduit to expand. Unlike a wedging force, the transverse force exerted by the separators on the shouldered slot is not prone to cause rotation of the connector. Furthermore, while a wedging force tends to compress the connector, with transversely acting separators the distance between the outer surface and the fiber conduit remains stable (thereby eliminating or minimizing the amount of re-calibration or readjustment required when splicing subsequent fibers). As a corollary benefit, the shouldered slot also serves as an alignment marker for aligning the connector within an installation apparatus, thus facilitating the process of splicing fibers. Accordingly, one aspect of the present invention is an optical fiber connector for mechanically connecting optical fibers. The connector comprises a connector body made of a highly elastic material, the connector body having end faces and a lateral outer surface, a fiber conduit extending along a longitudinal axis of the connector body, the fiber conduit being dimensioned to receive optica! fibers, and a shouldered slot having a pair of shoulders extending longitudinally between the end faces of the connector body, the shoulders dividing the shouldered slot into a narrow portion extending inwardly from the shoulders to the fiber conduit and a wide portion extending outwardly from the shoulders to the lateral outer surface, the wide portion of the shouldered slot having inner walls upon which equal and opposite transverse forces can be applied for expanding the shouldered slot and fiber conduit to thereby receive the optical fibers.

Another aspect of the present invention is method of connecting optical fibers. The method entails providing an optical fiber connector comprising a connector body made of a highly elastic material, the connector body having end faces and a lateral outer surface extending between the end faces, the connector body having a fiber conduit extending along a longitudinal axis of the connector body, the conduit being dimensioned to receive optical fibers, the connector body further having a shouldered slot having shoulders dividing the slot into a narrow portion and a wide portion extending longitudinally in the connector body between the end faces, the wide portion of the shouldered slot having inner walls extending from the shoulders to the lateral outer surface of the connector body. The method involves applying transverse forces on the inner walls of the wide portion of the shouldered slot to further separate the slot and expand the fiber conduit. The method further involves inserting optical fibers into the fiber conduit and releasing the transverse forces to enable the fiber conduit to contract onto the optical fibers.

Yet another aspect of the present invention is an apparatus for splicing optical fibers using a mechanical fiber connector having a connector body made of a highly elastic material and having a longitudinal fiber conduit adapted to receive the optical fibers. The apparatus comprises a base, a holder mounted on the base for holding the fiber connector to enable access to a shouldered slot formed in the connector body, the shouldered slot extending from an outer surface of the connector body to the fiber conduit and longitudinally from a first end of the connector body to a second end of the connector body, and first and second separators shaped to engage a pair of inner walls defining a wide portion of the shouldered slot, the separators being adapted to apply opposite transverse forces on the inner walls of the shouldered slot to expand the slot and fiber conduit. The apparatus also includes a first micro- positioning device for aligning a first optical fiber with the fiber conduit of the connector and a second micro-positioning device for aligning a second optical fiber with the fiber conduit of the connector.

BRIEF DESCRIPTION OF DRAWINGS

Various salient aspects of this invention will now be elucidated with reference to illustrative examples and specific embodiments that are depicted in the appended figures, in which: Figure 1 is an isometric view of a connector having a shouldered slot in accordance with one main embodiment of the present invention;

Figure 2 is an isometric view of a variant of the connector depicted in Figure 1 , the variant having a dividing slit; Figure 3 is a side sectional view of the connector shown in Figure 2; Figure 4 is a front view of the connector shown in Figure 1 ; Figure 5 is a transparent isometric view of the connector shown in Figure 1 ; Figure 6 is a side sectional view of the connector shown in Figure 1 ;

Figure 7 is a front view of the connector of Figures 1 or 2 showing transversely acting separators inserted into the wide portion of the shouldered slot for exerting transverse forces on the shouldered slot;

Figure 8 is a front view of a connector having multiple shouldered slots and multiple fiber conduits in accordance with another embodiment of the present invention;

Figure 9 is an isometric view of the connector illustrated in Figure 8; Figure 10 is a frontal view of a connector in which the wide portion of the slot has inwardly angled walls in accordance with a further embodiment of the present invention;

Figure 11 is an isometric view of the connector illustrated in Figure 10;

Figure 12 is an isometric view of an apparatus for mechanically splicing fibers that is specially designed to splice connectors of the types illustrated in Figures 1 or 2; and

Figure 13 is an enlarged isometric view of a portion of the apparatus of Figure 12, showing in particular a pivoting weight that can be pivoted onto the connector in order to restrain the connector when the connector is actuated. DETAILED DESCRIPTION

In general, and by way of overview, the present invention is embodied in various different types of optical fiber connectors each having a shouldered slot. The shouldered slot (or stepped slot) enables a pair of transversely acting separators to expand the shouldered slot and fiber conduit. Optical fibers can then be inserted into the expanded fiber conduit. Releasing the force exerted by the separators on the shouldered slot allows the fiber conduit to contract to an original size by virtue of the highly elastic or super elastic nature of the connector body. A highly elastic connector body may be made using shape memory alloys, for example. When the deformed connector returns to its original (undeformed) shape, the fiber conduit firmly holds the optical fibers in an abutting relationship. This optical fiber connector provides a purely mechanical splice in that it does not require glue or other bonding agent to hold the fibers together. As such, this glueless mechanical splice is reusable, immune to temperature fluctuations that would otherwise melt the glue (at extremely high temperatures) or make it brittle (at extremely cold temperatures). Since the connection is glueless, the fibers can be adjusted in situ, e.g. the fibers may be rotated to make polarization adjustments.

Connector

Figure 1 is an isometric view of an optical fiber connector, which is designated generally by reference numeral 10, having a shouldered slot 20 in accordance with one main embodiment of the present invention. This optical fiber connector, referred to herein as simply a "fiber connector" or "connector" is designed to connect or splice two optical fibers together in an end-to-end or abutting relationship. The optical fiber connector is designed to hold the fibers together without glue or bond to thus provide a purely mechanical splice, i.e. a glueless connection, that is therefore immune to the thermal and other problems typically associated with glued connections.

As depicted by way of example in Figure 1 , the connector 10 has a connector body 12 made of a highly elastic material. In main embodiments, the connector body is made of a shape memory alloy or other shape memory material. The connector body should be made of a highly elastic material, e.g. a shape memory material (SMM) such as a shape memory alloy (SMA) or other such material that is capable of being easily deformed and whose elasticity is high enough to return to its original, undeformed shape when the force or pressure is released from the connector body In main implementations of this technology, a shape-memory alloy is used for the connector body since shape memory alloys exhibit unusually high elasticity and are thus perfectly suited for this application. A Copper-Aluminum shape memory alloy has been found to provide excellent results. However, as will be appreciated by those of ordinary skill in the art who have had the benefit of reading this disclosure, other functionally equivalent shape-memory alloys can also be used. Indeed, any highly elastic material that has an elasticity comparable to the copper-aluminum alloy could be utilized to provide similar results. The optical fiber connector device of the present invention may, for example, be made from a polymeric material such as isostatic polybutene, shape ceramics such as zirconium with some addition of Cerium, Beryllium or Molybdenum, copper alloys including binary and ternary alloys, such as Copper - Aluminum alloys, Copper - Zinc alloys, Copper - Aluminum - Beryllium alloys, Copper - Aluminum - Zinc alloys and Copper - Aluminum - Nickel alloys, Nickel alloys such as Nickel - Titanium alloys and Nickel - Titanium - Cobalt alloys, Iron alloys such as Iron - Manganese alloys, Iron - Manganese - Silicon alloys, Iron - Chromium - Manganese alloys and Iron - Chromium - Silicon alloys, Aluminum alloys, and high elasticity composites which may optionally have metallic or polymeric reinforcement.

As further depicted in Figure 1 , the connector body 12 has end faces 14, 16 and a lateral outer surface 18 extending from one end face to the other. While the connector is shown as being generally cylindrical with a longitudinal slot formed therein, it will be appreciated that both the general shape of the connector body and the shape of the shouldered slot are merely illustrative and that other shapes may be employed.

As further depicted in Figure 1 , the shouldered slot 20 is formed in the connector body 12. The shouldered slot has a pair of shoulders 21 extending longitudinally between the end faces of the connector body. The shoulders (or steps) 21 divide the shouldered slot into a wide portion 22 and a narrow portion 24. As shown by way of example in Figure 1 , the narrow portion 24 (i.e. the small slot whose inner 25 walls are separated by a gap of distance d2) extends inwardly from the shoulders 21 to a fiber conduit 26. The wide portion 22 (i.e. the large slot whose inner walls 23 are separated by a gap of distance d1) extends outwardly from the shoulders 21 to the lateral outer surface 18. The wide portion 22 of the shouldered slot 20 has inner walls 23 upon which equal and opposite transverse forces can be applied for expanding the shouldered slot 20 and fiber conduit 26 to thereby receive the optical fibers. As shown by way of example in Figure 1 , the fiber conduit 26 extends along a longitudinal axis of the connector body 12. The fiber conduit 26 is dimensioned to receive optical fibers. The narrow portion 24 (small slot of gap d2) may include a slot extension 28 that extends through (beyond) the fiber conduit 26.

Figure 2 is an isometric view of a variant of the connector depicted in Figure 1. In this variant, the connector body 12 comprises a dividing slit 30 to divide the connector into independently operable portions 32, 34 to enable fibers to be inserted serially into different portions of the connector. In the example illustrated in Figure 2, the dividing slit 30 is disposed midway along the longitudinal axis of the connector body. In other variants, the dividing slit 30 may be located closer to one end face or the other (i.e. this slit need not be in the middle of the connector body). For greater clarity, Figure 3 is a side sectional view of the connector of Figure 2, depicting the layout of the fiber conduits and dividing slit.

Figure 4 is a frontal view of the connector of Figure 1 or of the connector of Figure 2, illustrating the wide and narrow portions of the shouldered slot. !n this particular embodiment, note that the shoulders (steps) 21 are orthogonal to the inner walls 23 of the wide portion and are also orthogonal to the inner walls 25 of the narrow portion. In other words, the inner walls 23 of the wide portion are parallel to the inner walls 25 of the narrow portion. In other words, in this embodiment, the narrow portion of the shouldered slot comprises substantially parallel inner walls and the wide portion of the shouldered slot also comprises substantially parallel inner walls. This geometry, however, is not essential, i.e. it is possible to have obliquely angled inner walls and/or to have steps/shoulders that are obliquely angled, as will be elaborated below with regard to a specific example presented in Figure 10 and Figure 11. Figure 5 is a transparent isometric view of the connector of Figure 1 , again showing a shouldered slot with a wide portion having parallel inner walls.

Figure 6 is a side sectional view of the connector of Figure 1 (showing the fiber conduit extending through the connector body).

Figure 7 is a frontal view of the connector 10 of Figure 1 showing transversely acting separators 50 inserted into the wide portion 22 of the shouldered slot 20. The separators 50 in this particular embodiment are each generally L-shaped with grips 52 that extend into the wide portion 22 of the shouldered slot 20 (but not into the narrow portion 24). The grips 52 have actuating surfaces 54 that abut and bear against the inner walls 23 of the wide portion 22 of the shouldered slot 20. The separators are pulled apart (separated) to exert equal and opposite transverse forces on the inner walls 23 of the wide portion of the shouldered slot. This application of force expands the fiber conduit 26. When these forces are released, the super elasticity of the connector body 12 causes the conduit 26 to contract, to thereby grip one or more fibers within the connector. In the embodiments presented thus far, the connector has a single shouldered slot. However, in another embodiment of the invention, depicted by way of example in Figure 8 and Figure 9, the connector body 12 may have a plurality of fiber conduits 26 each having a respective shouldered slot 20. As illustrated in Figures 8 and 9, the connector body 12 further comprises a deformation cavity 40 disposed between each adjacent pair of shouldered slots 20 to enable each slot and respective fiber conduit to be independently expanded and contracted.

Figures 10 and 11 depict a further embodiment of this invention in which the wide portion 22 of the shouldered slot 20 comprises obliquely inclined inner walls 60 that converge toward the lateral outer surface 18. The obliquely inclined inner walls 60 of the wide portion are designed to become substantially parallel when the equal and opposite transverse forces are applied on the obliquely inclined inner walls 60 by separators. The actuating surfaces of the separators may be modified to optimally grip the obliquely angled inner walls 60. In particular, Figure 10 is a frontal view of a connector in which the wide portion of the slot has inwardly angled walls. Figure 11 is an isometric view of the connector of Figure 10.

In another variant, the connector may be made to accommodate and splice together differently sized fibers. In other words, the fiber conduit may comprise a first section of diameter D1 and a second section of diameter D2, wherein D1 is not equal to D2. The fiber conduit may further comprise a third section of diameter D3, wherein D3 is different from D1 and D2.

In each of the foregoing embodiments and variants, the fiber conduit is shown as being round; however, it should be appreciated that the conduit may be any shape suitable for insertion and retention of fibers alone or fibers with cladding, coating or jackets. Furthermore, it should be understood that the conduit may include a flared or tapered opening to facilitate insertion. Furthermore, it will be appreciated that an index-matching gel may be employed, as needed, between the ends of two optical fibers in a manner already well known in the art.

Method Another aspect of this invention is a novel method of connecting optical fibers. This method is enabled by the shouldered slot of the novel connector which allows transverse (lateral) forces to be exerted on the inner walls of the wide portion of the shouldered slot. In other words, this novel method generally involves actuating the connector by applying lateral or transverse forces on the shouldered slot rather than applying a wedging force or some other non-transverse load. This method is advantageous since it neither compress the connector vertically nor is it prone to causing the connector to rotate under a slightly asymmetrical load.

This method entails providing an optical fiber connector (such as any of the connectors 10 described above). The method then entails applying transverse forces on the inner walls of the wide portion of the shouldered slot (as described above) to further separate the slot and expand the fiber conduit. These transverse forces may be applied using separators that pull apart (separate) the shouldered slot to thereby open the conduit. Optical fibers are then inserted into the expanded fiber conduit and the transverse forces are released. The fiber conduit then contracts due to the elasticity of the connector body. Contraction of the conduit onto the optica! fibers holds the fibers in place.

The fibers may be inserted concurrently (substantially simultaneously) or sequentially (serially) into the expanded conduit. To sequentially insert two optical fibers into the connector, transverse forces are applied sequentially to different portions of the connector body. The different portions of the connector body are divided by a dividing slit that allows one portion to deform without dimensionally affecting the other portion. The transverse forces are first applied to the wide portion of the slot that is disposed within a first portion of the connector body. This opens the first portion of the connector. A first fiber is inserted. The transverse forces are released to grip the first fiber. The procedure is then repeated for the second portion of the connector body to insert the second fiber. In one implementation, each fiber is inserted into an expanded portion of the fiber conduit until the optical fiber abuts an unexpanded portion of the fiber conduit. In one implementation that will be described below with regard to the fiber- installation apparatus, the method involves orienting the wide portion of the shouldered slot downwardly, disposing the wide portion of the shouldered slot on a pair of transverse separators, actuating at least one of the pair of transverse separators to exert equal and opposite transverse forces on the inner walls of the wide portion of the slot to thereby cause the slot and fiber conduit to expand. In one specific implementation, also described and illustrated below in greater detail, the method entails pivoting a weight onto an upwardly facing portion of the connector body to vertically restrain the connector body to thereby prevent displacement of the connector when at least one of the pair of separators is actuated. Apparatus Figure 12 is an isometric view of an apparatus 100 for mechanically splicing fibers that is specially designed to splice connectors of the types illustrated in Figures 1 and 2. In other words, the apparatus 100 is designed for splicing optical fibers using a mechanical fiber connector having a connector body made of a highly elastic material and having a longitudinal fiber conduit adapted to receive the optical fibers. This apparatus has a base 102, a holder 104 mounted on the base for holding the fiber connector to enable access to a shouldered slot formed in the connector body. In the example apparatus shown in Figure 12, the holder is movable relative to the base using a screw drive or equivalent mechanism. In order to use this apparatus to splice fibers, the shouldered slot of the connector should extend from an outer surface of the connector body to the fiber conduit and longitudinally from a first end of the connector body to a second end of the connector body. This enables the separators to fit inside the wide portion of the shouldered slot. As will be appreciated, the separators must mate with, or engage, the shouldered slot to exert the transverse forces. Therefore, the separators and shouldered slot can have other complementary shapes than what is depicted herein.

As depicted in Figure 12, the apparatus includes first and second separators 50a, 50b shaped to engage a pair of inner walls defining a wide portion of the shouldered slot in the connector. These separators are adapted to apply opposite transverse forces on the inner walls of the shouldered slot to expand the slot and fiber conduit. The separators can be driven by any suitable mechanical means, including manually powered means (e.g. screw drive system, gear system, etc.) or any automatically powered means (e.g. hydraulically, pneumatically, or electrically-driven actuators). Regardless how the separators are powered, they act to pull open the fiber conduit to enable insertion of the fibers.

As further depicted in Figure 12, the apparatus includes a first micro-positioning device 120 for aligning a first optical fiber with the fiber conduit of the connector, and a second micro-positioning device 130 for aligning a second optical fiber with the fiber conduit of the connector. As depicted in Figure 12, each of these micro- positioning devices preferably includes three orthogonally disposed linear screw drives for precision displacement of the fiber relative to the base in each of the X, Y, and Z axes. X, Y, Z adjustment knobs 122, 132 are provided to control displacement in each of the respective X, Y and Z axes. These adjustment knobs are thus used to align the fibers with the conduit of the connector held by the holder 104. An adjustment knob and adjustment screw are also provided for moving the holder 104 along one axis. The micro-positioning devices 120, 130 also include fibers clamps for holding the fibers while they are being displaced into alignment with the conduit and while they are being inserted into the conduit. Each clamp is released once the connector has gripped its respective fiber. As shown in Figure 13, a weight 110 is provided to restrain the connector. This weight can be pivoted (about pivot 1 12, as shown) onto an upwardly facing portion 19 of the connector 10 for restraining the connector when the first and second separators exert transverse forces on the inner walls of the shouldered slot. In one embodiment, as depicted in Figure 13, the holder 104 holds the connector 10 with the shouldered slot 20 facing downwardly to engage upwardly protruding separators 50a, 50b.

Figure 13 is an enlarged isometric view of a portion of the apparatus of Figure 12, showing in particular the pivoting weight 110 used to restrain the connector 10 when actuated. In other words, this prevents the connector from moving vertically upwardly when the shouldered slot is actuated (i.e. further separated apart). The connector 10 is placed with its shouldered slot facing downward to engage the transverse separators used to actuate the connector. As shown in Figure 13, the pivoting weight 110 pivots about pivot 112 to sit atop the upwardly facing outer surface of the connector. This weight is sufficiently heavy to prevent the connector from moving upwardly when the separators apply their transverse forces. In this embodiment, the weight is carried by the movable holder 104 although this weight could be attached to another part of the apparatus or it couid also simply be a free (unattached) weight that is placed onto the connector to keep it in place.

As shown in Figure 13, the first and second separators 50a, 50b may be generally L- shaped although other shapes of separators may be utilized, in one specific embodiment, the first separator 50a remains immobilized within the shouldered slot while the second separator 50b is mobile (movable) and can be pulled away from the first separator 50a. In other words, it is possible to either pull on both separators or to pull on only one of the two separators while keeping the other separator fixed, which results in an equal and opposite reaction force being exerted on the opposite inner wall. In either case, the conduit is forced open by the forces acting on the inner walls of the shouldered portion of the connector.

It is to be understood that the various features of the present invention might be incorporated into other types of connectors or installation apparatus and that other modifications, refinements or adaptations may occur to persons of skill in the art. It is to be understood that the present invention is not to be limited to the specific embodiments and examples disclosed and that modifications, refinements and variations are intended to be included within the scope of the appended claims. All such modifications, refinements and variations are intended to be included herein as being within the scope of the present invention. Furthermore, in the appended claims, the corresponding structures, materials, arts and equivalence of all means or step plus function elements are intended to include any structure, material or acts for performing the functions in combination with other elements as specifically claimed.

Claims

1. An optical fiber connector for mechanically connecting optical fibers, the connector comprising: a connector body made of a highly elastic material, the connector body having end faces and a lateral outer surface; a fiber conduit extending along a longitudinal axis of the connector body, the fiber conduit being dimensioned to receive optical fibers; and a shouldered slot having a pair of shoulders extending longitudinally between the end faces of the connector body, the shoulders dividing the shouldered slot into a narrow portion extending inwardly from the shoulders to the fiber conduit and a wide portion extending outwardly from the shoulders to the lateral outer surface, the wide portion of the shouldered slot having inner walls upon which equal and opposite transverse forces can be applied for expanding the shouldered slot and fiber conduit to thereby receive the optical fibers.

2. The optical fiber connector as claimed in claim 1 wherein the connector body comprises a plurality of fiber conduits each having a respective shouldered slot, the connector body further comprising a deformation cavity disposed between each adjacent pair of shouldered slots to enable each slot and respective fiber conduit to be independently expanded and contracted.

3. The optical fiber connector as claimed in claim 1 or 2 wherein the connector body comprises a dividing slit to divide the connector into independently operable portions to enable fibers to be inserted serially into different portions of the connector.

4. The optical fiber connector as claimed in claim 3 wherein the fiber conduit comprises a first section of diameter D1 and a second section of diameter D2, wherein D1 is not equal to D2.

5. The optical fiber connector as claimed in 4 wherein the fiber conduit further comprises a third section of diameter D3, wherein D3 is different from D1 and D2.

6. The optical fiber connector as claimed in any one of claims 1 to 5 wherein the narrow portion of the shouldered slot comprises substantially parallel inner walls.

7. The optical fiber connector as claimed in any one of claims 1 to 6 wherein the wide portion of the shouldered slot comprises substantially parallel inner walls.

8. The optical fiber connector as claimed in any one of claims 1 to 6 wherein the wide portion of the shouldered slot comprises obliquely inclined inner walls that converge toward the lateral outer surface.

9. The optical fiber connector as claimed in claim 8 wherein the obliquely inclined inner walls become substantially parallel when the equal and opposite transverse forces are applied on the obliquely inclined inner walls.

10. The optical fiber connector as claimed in any one of claims 1 to 9 wherein the connector body comprises a pair of shoulders disposed orthogonally to the inner walls of the narrow portion of the slot.

11. The optical fiber connector as claimed in any one of claims 1 to 10 wherein the connector body is made of a shape memory alloy.

12. The optical fiber connector as claimed in any one of claims 1 to 11 wherein the connector body is substantially cylindrical.

13. A method of connecting optical fibers, the method comprising: providing an optical fiber connector comprising a connector body made of a highly elastic material, the connector body having end faces and a lateral outer surface extending between the end faces, the connector body having a fiber conduit extending along a longitudinal axis of the connector body, the conduit being dimensioned to receive optical fibers, the connector body further having a shouldered slot having shoulders dividing the slot into a narrow portion and a wide portion extending longitudinally in the connector body between the end faces, the wide portion of the shouldered slot having inner walls extending from the shoulders to the lateral outer surface of the connector body; applying transverse forces on the inner walls of the wide portion of the shouldered slot to further separate the slot and expand the fiber conduit; inserting optical fibers into the fiber conduit; and releasing the transverse forces to enable the fiber conduit to contract onto the optical fibers.

14. The method as claimed in claim 13 comprising sequentially inserting two fibers by first applying transverse forces to the wide portion of the slot that is disposed within a first portion of the connector body that is divided by a dividing slit from a second portion of the connector body; releasing the transverse forces; applying transverse forces to the wide portion of the slot disposed within the second portion of the connector body; and releasing the transverse forces.

15. The method as claimed in claim 14 wherein each fiber is inserted into an expanded portion of the fiber conduit until the optical fiber abuts an unexpanded portion of the fiber conduit.

16. The method as claimed in claim 13 comprising orienting the wide portion of the shouldered slot downwardly, disposing the wide portion of the shouldered slot on a pair of transverse separators, actuating at least one of the pair of transverse separators to exert equal and opposite transverse forces on the inner walls of the wide portion of the slot to thereby cause the slot and fiber conduit to expand.

17. The method as claimed in claim 16 comprising pivoting a weight onto an upwardly facing portion of the connector body to vertically restrain the connector body to thereby prevent displacement of the connector when at least one of the pair of separators is actuated.

18. An apparatus for splicing optical fibers using a mechanical fiber connector having a connector body made of a highly elastic materia! and having a longitudinal fiber conduit adapted to receive the optical fibers, the apparatus comprising: a base; a holder mounted on the base for hoiding the fiber connector to enable access to a shouldered slot formed in the connector body, the shouldered slot extending from an outer surface of the connector body to the fiber conduit and longitudinally from a first end of the connector body to a second end of the connector body; first and second separators shaped to engage a pair of inner walls defining a wide portion of the shouldered slot, the separators being adapted to apply opposite transverse forces on the inner walls of the shouldered slot to expand the slot and fiber conduit; a first micro-positioning device for aligning a first optical fiber with the fiber conduit of the connector; and a second micro-positioning device for aligning a second optical fiber with the fiber conduit of the connector.

19. The apparatus as claimed in claim 18 wherein the holder holds the connector with the shouldered slot facing downwardly to engage upwardly protruding separators.

20. The apparatus as claimed in claim 18 further comprising a weight that can be pivoted onto an upwardly facing portion of the connector for restraining the connector when the first and second separators exert transverse forces on the inner walls of the shouldered slot.

21. The apparatus as claimed in claim 20 wherein the first and second separators are L-shaped.

22. The apparatus as claimed in claim 21 wherein the first separator remains immobilized within the shouldered slot while the second separator is pulled away from the first separator.