WO2021247842A1 - Bare fiber optical alignment device with gel venting - Google Patents

Abstract

The present disclosure relates to methods, devices and systems for co-axially aligning first and second optical fibers to provide an optical coupling between the first and second optical fibers. A fiber engagement element is used to force the first and second optical fibers into an alignment groove. The alignment groove includes a gel venting cavity for receiving gel displaced by the first and second optical fibers as the optical fibers are inserted axially into the alignment groove.

Description

BARE FIBER OPTICAL ALIGNMENT DEVICE WITH GEL VENTING

CROSS-REFERENCE TO RELATED APPLICATION This application is being filed on June 3, 2021 as a PCT International Patent Application and claims the benefit of U.S. Patent Application Serial No. 63/034,129, filed on June 3, 2020, the disclosure of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to fiber optic connection components such as fiber optic adapters. More particularly, the present disclosure relates to ferrule-less fiber optic connection components, systems and methods.

BACKGROUND

Fiber optic communication systems are becoming prevalent in part because service providers want to deliver high bandwidth communication capabilities (e.g., data and voice) to customers. Fiber optic communication systems employ a network of fiber optic cables to transmit large volumes of data and voice signals over relatively long distances. Optical fiber connectors are an important part of most fiber optic communication systems. Fiber optic connectors allow two optical fibers to be quickly optically connected without requiring a splice. Fiber optic connectors can be used to optically interconnect two lengths of optical fiber. Fiber optic connectors can also be used to interconnect lengths of optical fiber to passive and active equipment.

A typical fiber optic connector includes a ferrule assembly supported at a distal end of a connector housing. A spring is used to bias the ferrule assembly in a distal direction relative to the connector housing. The ferrule functions to support an end portion of at least one optical fiber (in the case of a multi-fiber ferrule, the ends of multiple fibers are supported). The ferrule has a distal end face at which a polished end of the optical fiber is located. When two fiber optic connectors are interconnected, the distal end faces of the ferrules abut one another and the ferrules are forced proximally relative to their respective connector housings against the bias of their respective springs. With the fiber optic connectors connected, their respective optical fibers are coaxially aligned such that the end faces of the optical fibers directly oppose one another. In this way, an optical signal can be transmitted from optical fiber to optical fiber through the aligned end faces of the optical fibers. For many fiber optic connector styles (LC, SC, MPO), alignment between two fiber optic connectors is provided through the use of an intermediate fiber optic adapter.

Another type of fiber optic connector can be referred to as a ferrule-less fiber optic connector. In a ferrule-less fiber optic connector, an end portion of an optical fiber corresponding to the ferrule-less fiber optic connector is not supported by a ferrule. Instead, the end portion of the optical fiber is a free end portion. Similar to the ferruled connectors described above, fiber optic adapters can be used to assist in optically coupling together two ferrule-less fiber optic connectors. Example ferrule-less fiber optic connectors and/or fiber optic adapters are disclosed by PCT Publication Nos. WO 2012/112344; WO 2013/117598; WO 2017/081306; WO 2016/100384;

WO 2016/043922; and U.S. Patent Nos. 8,870,466 and 9,575,272.

Fiber optical adapters are used to optically couple together optical fiber tips of optical connectors. Fiber optical adapters can include specialized fiber alignment devices to receive bare optical fibers and align the fiber tips to enable the transfer of optical signals therebetween. Optical connectors can be secured to the optical adapters when received at the ports of the optical adapters.

Improvements are needed in the area of fiber alignment for multi-fiber fiber optic connectors and single fiber optic connectors.

SUMMARY

Aspects of the present disclosure relates to fiber alignment systems, apparatuses/devices, and methods for aligning optical fibers of ferrule-less fiber optic connectors.

Aspects of the present disclosure also relate to fiber alignment systems, apparatuses/devices, and methods for enhancing insertion loss performance relating to optical connection locations/interface between optical fibers. In certain examples, features in accordance with the principles of the present disclosure allow insertion loss to become more stable along the entire alignment system. In certain examples, the fiber alignment systems include fiber alignment grooves designed with excess volume for accommodating the displacement of gel (e.g., index matching gel) that is displaced when optical fibers are aligned and optically coupled together. In one example, the excess volume can be provided within a fiber alignment groove by a gel receiving cavity provided at a closed end/side of the fiber alignment groove.

In certain examples, the fiber alignment systems of the ferrule-less fiber optic connectors can be configured to accommodate any number of optical fibers. In certain examples, the fiber alignment systems can be configured to accommodate fiber optic connectors including at least one, two, four, eight, twelve, sixteen, twenty-four, thirty-two, forty-eight, or more optical fibers. While aspects of the present disclosure are particularly useful for systems for aligning sets of multiple optical fibers (e.g., systems for aligning the optical fibers of multi-fiber optical connectors) because of the ability to provide high optical connection densities, the features and advantages of the present disclosure are also applicable to systems for aligning single pairs of optical fibers (e.g., systems for aligning the optical fibers of single fiber optical connectors).

Another aspect of the present disclosure relates to an alignment system for aligning optical fibers of ferrule-less fiber optic connectors (e.g., fiber optic connectors having fibers not supported by a ferrule). The alignment system includes a contact member adapted to press optical fibers desired to be optically coupled together into an alignment groove when the optical fibers are inserted therein. The contact member can have a contact surface that contacts the optical fibers desired to be optically coupled together directly at or in very close proximity to the fiber end tips to press the optical fibers within the alignment groove. The contact member preferably extends across an optical interface location between the optical fibers desired to be optically coupled together so as to contact both of the optical fibers with a single contact member. The use of the single contact member for contacting both of the optical fibers desired to be aligned enables the optical fibers to be contacted directly at or in very close proximity to the fiber tips. The contact member can include a contact surface that contacts the optical fibers desired to be aligned and traverses the location where end faces of the tips of the optical fibers oppose each other. The alignment groove can include a gel venting cavity positioned on an opposite side of the optical fibers from the contact member for receiving gel displaced by the optical fibers at the optical interface location during the fiber insertion process as the optical fibers are inserted into the alignment groove. In one example, the contact member can be an intermediate member through which spring force is transferred from one or more springs to the optical fibers.

A variety of additional aspects will be set forth in the description that follows. The aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the examples disclosed herein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of the description, illustrate several aspects of the present disclosure. A brief description of the drawings is as follows:

FIG. l is a perspective view of a bare fiber optical alignment system in accordance with the principles of the present disclosure;

FIG. 2 is an exploded view of the bare fiber optical alignment system of

FIG. 1;

FIG. 3 is a cross-sectional view cut cross-wise through fiber alignment grooves of the bare fiber alignment system of FIG. 1;

FIG. 4 is a cross-sectional view cut lengthwise through of the fiber alignment grooves of the bare fiber alignment system of FIG. 1;

FIG. 5 is an enlarged view of a portion of FIG. 3;

FIG. 6 is a transverse cross-sectional view of one of the fiber alignment grooves of the bare fiber alignment system of FIG. 1 with reference lines delineating different sections of the fiber alignment groove shown in dashed line;

FIG. 7 is the transverse cross-sectional view of FIG. 6 with reference planes corresponding to groove defining surfaces labeled and angles also labeled;

FIG. 8 is the transverse cross-sectional view of FIG. 6 with additional angles labeled;

FIG. 9 is another transverse cross-sectional view of two of the fiber alignment grooves of the bare fiber alignment system of FIG. 1 and a pressing member that opposes open sides of the fiber alignment grooves, index matching gel is shown displaced within fiber receiving portions of the fiber alignment grooves;

FIG. 10 the transverse cross-sectional view of FIG. 9 with optical fibers inserted within the fiber receiving portions of the fiber alignment grooves and with the indexing gel displaced to gel receiving cavities of the fiber alignment grooves; and FIG. 11 is a schematic view of a fiber optic adapter in which a fiber alignment device in accordance with the principles of the present disclosure can be mounted, the fiber optic adapter includes opposite adapter ports in which ferrule-less fiber optic connectors can be secured with bare optical fibers of the fiber optic connectors received and aligned within the fiber alignment device.

DETAILED DESCRIPTION

Aspects of the present disclosure relates to alignment systems for aligning optical fibers of ferrule-less (e.g., bare fiber) fiber optic connectors to provide optical connections between the optical fibers of the fiber optic connectors. The aspects apply to the alignment of optical fibers of single fiber optical connectors and multi-fiber optical connectors. The alignment systems preferably include fiber alignment grooves having gel venting cavities for receiving index matching gel that is displaced from alignment portions of the fiber alignment grooves when optical fibers are inserted into the alignment grooves. In one example, the gel venting cavities are provided at closed sides/ends of the fiber alignment grooves that are opposite from open sides/ends of the fiber alignment grooves.

FIGS. 1-4 depict a bare fiber alignment device 20 in accordance with the principles of the present disclosure for co-axially aligning first and second optical fibers 22a, 22b (e.g., sets of first and second optical fibers 22a, 22b) to provide an optical coupling between the first and second optical fibers 22a, 22b. The bare fiber alignment device 20 includes a fiber alignment member 24 (e.g., a substrate) defining fiber alignment grooves 26 for receiving the first and second optical fibers 22a, 22b. The fiber alignment grooves 26 define fiber insertion axes 28 along which the first and second fibers 22a, 22b are moved in opposite directions (e.g., toward one another) when inserted into the fiber alignment grooves 26. The bare fiber alignment device 20 includes an optical coupling reference location 30 (see FIG. 4) at which end faces of the first and second optical fibers 22a, 22b will oppose one another when the first and second optical fibers 22a, 22b are optically coupled together. The optical coupling reference location 30 is positioned along the fiber alignment groove 26 preferably at a central location centered between opposite ends of the fiber alignment grooves 26.

Referring to FIGS. 2 and 3, the bare fiber alignment device 20 includes pressing members 32 (e.g., beams) defined by a pressing substrate 34 that mounts one the fiber alignment member 24. As best shown at FIG. 3 and 5, the pressing members 32 have fiber contact sides 36 that oppose open sides 38 of the fiber alignment groove 26. As depicted at FIG. 4, the pressing members 32 extend across the optical coupling reference location 30 such that the fiber contact side 36 is adapted to engage both the first and second optical fibers 22a, 22b when the first and second optical fibers 22a, 22b are optically coupled together in the fiber alignment groove 26. The pressing members 32 each correspond to two of the fiber alignment grooves 26 and are adapted to apply a spring force to each of the first and second optical fibers 22a, 22b to press the first and second optical fibers 22a, 22b into their respective fiber alignment groove 26 when the first and second optical fibers 22a, 22b are optically coupled together within the fiber alignment grooves 26. In the depicted example, a spring structure 40 supplies spring load that is transferred through the pressing member 32 to the first and second optical fibers 22a, 22b. Thus, the pressing members 32 are intermediate structures through which the spring load is transferred.

Referring to FIG. 5, the fiber alignment grooves 26 include closed sides 42 positioned opposite the open sides 38 of the fiber alignment grooves 26. The fiber alignment grooves 26 are each defined by first and second fiber alignment surfaces 44, 46 that are angled with respect to one another so as to converge as the first and second alignment surfaces 44, 46 extend in a direction from the open side 38 toward the closed side 42 of each of the fiber alignment grooves 26.

Referring to FIG. 6, the fiber alignment grooves 26 each include a fiber receiving region 48 and a displaced gel receiving region 50 (e.g., a vent, cavity, etc.). The fiber receiving region 48 and the displaced gel receiving region 50 respectively having first and second transverse cross-sectional shapes SI, S2 delineated by a fiber profile reference arc 52 that extends between fiber contact locations 54, 56 of the first and second alignment surfaces 44, 46. The fiber profile reference arc 52 is an imaginary arc coinciding with an arc 58 (see FIG. 5) defined by a side of the first or second optical fiber 22a, 22b that faces toward the closed side 42 of the fiber alignment groove 26 when the first and second optical fibers 22a, 22b are pressed into the fiber alignment groove 26 by the pressing member 32. The first transverse cross-sectional shape SI is defined between the open side 38 (shown bounded by imaginary reference line 60 at FIG. 6) of the fiber alignment groove 26 and the fiber profile reference arc 52. The first transverse cross- sectional shape SI is also defined between the first and second alignment surfaces 44, 46. The second transverse cross-sectional shape S2 is defined between the fiber profile reference arc 52 and the closed side 42 of the fiber alignment groove 26. The second transverse cross-sectional shape S2 is also defined between first and second cavity defining surfaces 62, 64 that respectively extend from the first and second fiber alignment surface 44, 46 to the closed side 42. In certain examples, the second transverse cross- sectional shape S2 has an area that is at least 10, 15, 20, 25 or 30 percent as large as an area of the first transverse cross-sectional shape SI.

Referring to FIG. 9, index matching gel 66 or other type of gel such as a fiber cleaning gel is positioned within the fiber receiving region 48 adjacent the optical coupling reference location 30 prior to insertion of the first and second optical fibers 22a, 22b in the fiber alignment grooves 26. When the first and second optical fibers 22a, 22b are inserted into corresponding ones of the fiber alignment grooves 26, at least a portion 66a of the index matching gel 66 is displaced from the fiber receiving region 48 into the displaced gel receiving region 50 as shown at FIG. 10. As shown at FIGS. 9 and 10, the fiber contacting side of one of the pressing members 32 opposes the open sides 38 of two of the fiber alignment grooves 26 along the lengths of the grooves including across the optical coupling reference location 30. Thus, the pressing member 32 blocks or limits the flow of index matching gel 66 as the gel is displaced by the first and second optical fibers 22a, 22b as the first and second optical fibers 22a, 22b are inserted axially through the fiber alignment grooves 26 since the pressing member 32 provides at least partial containment of the index matching gel 66. If the gel were not allowed to escape from the fiber alignment groove 26, the gel could become hydrostatically loaded between the tips of the first and second optical fibers 22a, 22b to prevent the fiber tips from properly co-axially aligning and preferably contacting one another. The displaced gel receiving region 50 provides an open volume adjacent the closed side 42 of the fiber alignment groove 26 at the optical coupling reference location 30 into which the gel can flow when displaced by the first and second optical fibers 22a, 22b during fiber insert to prevent hydrostatic loading of the gel or to otherwise prevent the gel from interfering with proper alignment of the first and second optical fibers 22a, 22b.

In one example, the first and second optical fibers 22a, 22b each define a third transverse cross-sectional shape S3 and the area of the second transverse cross-sectional shape S2 is at least 10, 15, 20, 25 or 30 percent as large as an area of the third transverse cross-sectional shape S3.

In one example, the first and second cavity defining surfaces 62, 64 converge as the first and second cavity defining surfaces 62, 64 extend toward the closed side 42 of the fiber alignment groove 26 at a convergence angle A2 that is less than or equal to one third of a convergence angle A1 of the first and second fiber alignment surfaces 44, 46 (see FIG. 8). In one example, as shown at FIG. 7, the first fiber alignment surface 44 is aligned along a first reference plane PI, the second alignment surface 46 is aligned along a second reference plane P2, and the first and second reference planes PI, P2 intersect at a reference line L positioned such that the closed side 42 of the fiber alignment groove 26 is offset from the reference line L in a direction away from the open side 38 of the fiber alignment groove 26.

In certain examples, the first and second cavity defining surfaces 62, 64 that extend respectively from the first and second fiber alignment surfaces 44, 46 toward the closed side 42 of the fiber alignment groove 26 are respectively oriented at oblique angles A3 respect to reference planes PI, P2 corresponding to the first and second fiber alignment surfaces 44, 46. In one example, the angles A3 are at least 10, 20 or 30 degrees.

In certain examples of the present disclosure, the pressing member 32 is flexible. In certain examples, the pressing member 32 is an intermediate force transfer member configured for transferring the spring force from one or more springs to each of the first and second optical fibers 22a, 22b. In certain examples, the pressing member 32 includes a spring contact side positioned opposite from the fiber contact side 36, wherein a spring or springs of the spring structure 40 apply the spring force to the spring contact side, wherein the spring force is transferred through the pressing member 32 from the spring contact side to the fiber contact side 36, and wherein the spring force is transferred from the fiber contact side 36 to each of the first and second optical fibers 22a, 22b. In certain examples, the pressing member 32 is a beam that traverses the optical coupling reference location 30 and is parallel to the fiber alignment groove 26, wherein spring force is provided by a spring, and wherein the spring force is transferred through the beam to the first and second optical fibers 22a, 22b to spring bias the first and second optical fibers 22a, 22b into the fiber alignment groove 26. In certain examples, the beam is integrated as part of a metal, ceramic, or plastic component. In certain examples, the beam is configured to engage both the first and second optical fibers 22a. 22b directly at tips of the first and second optical fibers 22a, 22b. In certain examples, the fiber alignment member 24 defines a plurality of the fiber alignment grooves 26 and the apparatus includes a plurality of the pressing members 32. In certain examples, the fiber alignment grooves 26 are parallel, and wherein each pressing member 32 corresponds to no more than two of the fiber alignment grooves 26.

It will be appreciated that fiber optic alignment systems in accordance with the principles of the present disclosure can be incorporated into fiber optic adapters having ports for receiving ferrule-less fiber optic connectors. Example configurations for the fiber optic connectors as well as example configurations for adapter housings in which alignment systems in accordance with the principles of the present disclosure can be incorporated are disclosed by United States Provisional Patent Application Serial No. 62/972,776; PCT International Publication No. 2020/046709 and PCT International Application No. PCT/US2019/063026, which are hereby incorporated by reference in their entireties.

FIG. 11 schematically depicts an example fiber optic adapter 100 into which bare fiber alignment devices 20 in accordance with the principles of the present disclosure can be integrated. The fiber optic adapter 100 includes an adapter housing 102. The bare fiber alignment device 20 is housed within the adapter housing 102. The adapter housing 102 defines connector ports 104a, 104b on opposite sides of the bare fiber alignment device 20 for receiving ferrule-less fiber optic connectors 106a, 106b respectively supporting the first and second optical fibers 22a, 22b. In certain examples, the fiber optic connectors 106a, 106b are adapted to be removably secured (e.g., latched) within the connector ports 104a, 104b. In certain examples, the first and second optical fibers 22a, 22b are received in the bare fiber alignment device 20 and optically coupled to one another when the fiber optic connectors 106a, 106b are secured within the connector ports 104a, 104b.

Alignment systems in accordance with the principles of the present disclosure can include alignment structures for co-axially aligning optical fibers to provide optical connections between the aligned optical fibers. The alignment structures can define alignment grooves for receiving an aligning the optical fibers. The alignment grooves can be defined by structures such as substrates which may each define one or more grooves. The substrates can include members such as plates which may have a ceramic construction, a metal construction, a plastic construction or other constructions. The alignment grooves can include grooves having v-shaped cross-sections (e.g., v- grooves) grooves having u-shaped cross-sections, grooves having through-shaped cross- sections, grooves having half-circle shaped cross-sections or grooves having other shapes. In other examples, alignment grooves in accordance with the principles of the present disclosure can be defined by parallel cylindrical rods oriented in a side-by-side relationship. Various alignment structures defining grooves are disclosed by PCT International Publication Number WO 2018/020022, which is hereby incorporated by reference in its entirety. In certain examples, index matching gel can be used between opposing ends of optical fibers aligned within the alignment structures, and alignment grooves can include cavities for receiving index matching gel displaced by the optical fibers as the optical fibers are inserted into the alignment grooves.

Alignment systems in accordance with the principles of the present disclosure can also include contact or pressing elements (i.e., contact members, contact components, contact features, pressing members, pressing components, pressing features, etc.) that function to bias optical fibers into the alignment structures to ensure effective co axial alignment of the optical fibers at the optical interface where end faces of the optical fibers oppose one another. Each contact or pressing element can include an element that is moveable relative to the alignment structure and that is configured to press first and second optical fibers within the alignment structure. A single one of the contact elements is preferably configured to press both of its corresponding first and second optical fibers into an alignment groove. The contact element preferably engages each of the first and second optical fibers directly at or in close proximity to tips of the optical fibers. In this way, the contact element can bias the optical fibers directly at or in close proximity to the optical interface location between the optical fibers to ensure effective alignment of the opposed end faces of the optical fibers. The contact element includes a first contact region adapted to press the first optical fiber into the fiber alignment structure and a second contact region adapted to press the second optical fiber into the fiber alignment structure. Extending along the contact element in one direction directly from the first contact region to the second contact region, the contact element traverses an optical interface reference location between the first and second optical fibers. The optical interface reference location is the location within the fiber alignment structure where the end faces of the first and second optical fibers oppose each other when the first and second optical fibers are fully inserted within the fiber alignment structure. The contact element is adapted to spring bias the first and second optical fibers into the fiber alignment structure. The spring biasing force can be derived from the inherent resiliency (i.e., spring-like characteristics) of the contact element, or by the resiliency of a spring or springs that apply spring load through the contact element, or by both the inherent resiliency of the contact element and by the resiliency of a spring or springs that apply spring load through the contact element. The diameters of the optical fibers are larger than a spacing/clearance between the contact element and the alignment structure such that when the optical fibers are inserted into the alignment structure, the contact element is required to be forced away from the alignment structure by the optical fibers to allow the optical fibers to be received/accommodated within the alignment structures. It will be appreciated that during fiber insertion, the optical fibers move the contact element away from the alignment structure against the spring biasing force which resists such movement. In this way, the spring biasing force for pressing the optical fibers into the alignment structure is applied by the contact element to the optical fibers.

The portions of the optical fibers received within alignment grooves in accordance with the present disclosure are preferably bare fibers. As used herein, a bare fiber is a section of optical fiber that does not include any coating. Instead, the bare fiber includes a core surrounded by a cladding layer. The optical fiber is “bare” because the cladding layer is exposed and not covered by a supplemental coating layer such as acrylate.

As used herein, the term, “groove,” is defined generally as an elongate structure that can receive and support an optical fiber. In one example, the elongate structure can have two surfaces that are angled such that when an optical fiber lies within the groove, the optical fiber makes line contact with the two surfaces. The elongate structure can be defined by one component (e.g., a groove in a substrate such as a plate) or multiple components (e.g., a groove defined by two parallel rods). Generally a groove will have an open side and a closed side in which an optical fiber sits. In one example, the groove may include a v-groove that has angled surfaces. In such an example, the v-groove will have a structure that preferably provides two lines of contact with an optical fiber inserted therein. In this way, the line/point contact with the v-groove assists in providing accurate alignment of the optical fibers.

In certain examples, optical fibers include a core, a cladding layer surrounding the core, one or more coating layers surrounding the cladding layer, and a buffer layer surrounding the one or more coating layers. In certain examples, the core can have an outer diameter in the range of 8-12 microns, the cladding can have an outer diameter in the range of 120-130 microns, the one or more coatings can have an outer diameter in the range of 240-260 microns, and the outer buffer layer can have an outer diameter in the range of 800-1,000 microns. In certain examples, the outer buffer layer can be a loose or tight buffer tube having an outer diameter of about 900 microns. In certain examples, only the core and the cladding of the optical fibers are supported within the alignment structure.

It will also be appreciated that the core and the cladding can be constructed of a material suitable for conveying an optical signal such as glass (e.g., a silica-based material). The cladding layer can have an index of refraction that is less than the index of refraction of the core. This difference between the index of refraction of the cladding layer and the index of refraction of the core allows an optical signal that is transmitted through the optical fiber to be confined to the core. The one or more coating layers typically have a polymeric construction such as acrylate.

The various examples described above are provided by way of illustration only and should not be construed to limit the scope of the present disclosure. Those skilled in the art will readily recognize various modifications and changes that may be made with respect to the examples and applications illustrated and described herein without departing from the true spirit and scope of the present disclosure.

Claims

CLAIMS What is claimed is:

1. An apparatus for co-axially aligning first and second optical fibers to provide an optical coupling between the first and second optical fibers, the apparatus comprising: a fiber alignment member defining a fiber alignment groove for receiving the first and second optical fibers, the fiber alignment groove defining a fiber insertion axis along which the first and second fibers are moved when inserted into the fiber alignment groove, the apparatus including an optical coupling reference location at which end faces of the first and second optical fibers will oppose one another when the first and second optical fibers are optically coupled together, the optical coupling reference location being positioned along the fiber alignment groove; a pressing member having a fiber contact side that opposes an open side of the fiber alignment groove and extends across the optical coupling reference location such that the fiber contact side is adapted to engage both the first and second optical fibers when the first and second optical fibers are optically coupled together in the fiber alignment groove, and where the pressing member applies a spring force to each of the first and second optical fibers to press the first and second optical fibers into the fiber alignment groove when the first and second optical fibers are optically coupled together within the fiber alignment groove; the fiber alignment groove including a closed side positioned opposite the open side, wherein the fiber alignment groove is defined by first and second fiber alignment surfaces that are angled with respect to one another so as to converge as the first and second alignment surfaces extend in a direction from the open side toward the closed side of the fiber alignment groove, the fiber alignment groove including a fiber receiving region and a displaced gel receiving region, the fiber receiving region and the displaced gel receiving region respectively having first and second transverse cross-sectional shapes delineated by a fiber profile reference arc that extends between fiber contact locations of the first and second alignment surfaces, the fiber profile reference arc coinciding with an arc defined by a side of the first or second optical fiber that faces toward the closed side of the fiber alignment groove when the first and second optical fibers are pressed into the fiber alignment groove, the first transverse cross-sectional shape being defined between the open side of the fiber alignment groove and the fiber profile reference arc, the second transverse cross-sectional shape being defined between the fiber profile reference arc and the closed side of the fiber alignment groove, and the second transverse cross-sectional shape having an area that is at least 10 percent as large as an area of the first transverse cross-sectional shape; and gel positioned within the fiber receiving region adjacent the optical coupling reference location, wherein when the first and second optical fibers are inserted into the fiber alignment groove at least a portion of the gel is displaced from the fiber receiving region into the displaced gel receiving region.

2. The apparatus of claim 1, wherein the area of the second transverse cross- sectional shape is at least 15 percent as large as the area of the first transverse cross- sectional shape.

3. The apparatus of claim 1, wherein the area of the second transverse cross- sectional shape is at least 20 percent as large as the area of the first transverse cross- sectional shape.

4. The apparatus of claim 1, wherein the area of the second transverse cross- sectional shape is at least 25 or 30 percent as large as the area of the first transverse cross- sectional shape.

5. The apparatus of claim 1, wherein the first and second optical fibers each define a third transverse cross-sectional shape, and wherein the area of the second transverse cross-sectional shape is at least 10, 15, 20, 25 or 30 percent as large as an area of the third transverse cross-sectional shape.

6. The apparatus of claim 1, wherein the second transverse cross-sectional shape includes first and second shape-defining surfaces that extend respectively from the first and second fiber alignment surfaces toward the closed side of the fiber alignment groove, wherein the first and second shape-defining surfaces converge as the first end second shape-defining surfaces extend toward the closed side at a convergence angle that is less than or equal to one third of a convergence angle of the first and second fiber alignment surfaces.

7. The apparatus of claim 1, wherein the first alignment surface is aligned along a first reference plane, wherein the second alignment surface is aligned along a second reference plane, wherein the first and second reference planes intersect at a reference line, and wherein the closed side of the fiber alignment groove is offset from the reference line in a direction away from the open side of the fiber alignment groove.

8. The apparatus of claim 1, wherein the second transverse cross-sectional shape includes first and second shape-defining surfaces that extend respectively from the first and second fiber alignment surfaces toward the closed side of the fiber alignment groove, the first and second shape-defining surfaces being respectively oriented at oblique angles respect to reference planes corresponding to the first and second fiber alignment surfaces.

9. The apparatus of any of claims 1-8, wherein the pressing member is flexible.

10. The apparatus of claim 9, wherein the pressing member is an intermediate force transfer member configured for transferring the spring force from one or more springs to each of the first and second optical fibers.

11. The apparatus of claim 10, wherein the pressing member includes a spring contact side positioned opposite from the fiber contact side.

12. The apparatus of claim 11, wherein the spring or springs apply the spring force to the spring contact side, wherein the spring force is transferred through the pressing member from the spring contact side to the fiber contact side, and wherein the spring force is transferred from the fiber contact side to each of the first and second optical fibers.

13. The apparatus of any of claims 1-8, wherein the pressing member is a beam that traverses the optical coupling reference location and is parallel to the fiber alignment groove, wherein the spring force is provided by a spring, and wherein the spring force is transferred through the beam to the first and second optical fibers to spring bias the first and second optical fibers into the fiber alignment groove.

14. The apparatus of claim 13, wherein the beam is integrated as part of a metal, ceramic, or plastic component.

15. The apparatus of claim 13, wherein the beam is configured to engage both the first and second optical fibers directly at tips of the first and second optical fibers.

16. The apparatus of any of claims 1-8, wherein the fiber alignment member defines a plurality of the fiber alignment grooves and the apparatus includes a plurality of the pressing members.

17. The apparatus of claim 16, wherein the fiber alignment grooves are parallel, and wherein each pressing member corresponds to no more than two of the fiber alignment grooves.

18. An apparatus for co-axially aligning first and second optical fibers to provide an optical coupling between the first and second optical fibers, the apparatus comprising: a fiber alignment member defining a fiber alignment groove for receiving the first and second optical fibers, the fiber alignment groove defining a fiber insertion axis along which the first and second fibers are moved when inserted into the fiber alignment groove, the apparatus including an optical coupling reference location at which end faces of the first and second optical fibers will oppose one another when the first and second optical fibers are optically coupled together, the optical coupling reference location being positioned along the fiber alignment groove; a pressing member for pressing at least one of the first and second optical fibers into the fiber alignment groove; the fiber alignment groove including a closed side positioned opposite the open side, wherein the fiber alignment groove is defined by first and second fiber alignment surfaces that are angled with respect to one another so as to converge as the first and second alignment surfaces extend in a direction from the open side toward the closed side of the fiber alignment groove, the fiber alignment groove including a fiber receiving region and a displaced gel receiving region, the fiber receiving region being located between the open side and the displaced gel receiving region and the displaced gel receiving region being located at the closed side of the fiber alignment groove, the first alignment surface being aligned along a first reference plane and the second alignment surface being aligned along a second reference plane, the first and second reference planes intersecting at a reference line, and the closed side of the fiber alignment groove being offset from the reference line in a direction away from the open side of the fiber alignment groove so that the reference line is located inside the displaced gel receiving region; and gel positioned within the fiber receiving region adjacent the optical coupling reference location, wherein when the first and second optical fibers are inserted into the fiber alignment groove at least a portion of the gel is displaced from the fiber receiving region into the displaced gel receiving region.

19. The apparatus of claim 18, wherein the displaced gel receiving region is defined between first and second cavity-defining surfaces that extend respectively from the first and second fiber alignment surfaces toward the closed side of the fiber alignment groove, wherein the first and second cavity-defining surfaces converge as the first end second shape-defining surfaces extend toward the closed side at a convergence angle that is less than or equal to one third of a convergence angle of the first and second fiber alignment surfaces.

20. The apparatus of claim 18, wherein the displaced gel receiving region is defined between first and second cavity-defining surfaces that extend respectively from the first and second fiber alignment surfaces toward the closed side of the fiber alignment groove, the first and second cavity-defining surfaces being respectively oriented at oblique angles respect to reference planes corresponding to the first and second fiber alignment surfaces.

21. The apparatus of any of claims 18-20, wherein the pressing member is flexible.

22. The apparatus of claim 21, wherein the pressing member is an intermediate force transfer member configured for transferring the spring force from one or more springs to each of the first and second optical fibers.

23. The apparatus of claim 22, wherein the pressing member includes a spring contact side positioned opposite from a fiber contact side, wherein the spring or springs apply the spring force to the spring contact side, wherein the spring force is transferred through the pressing member from the spring contact side to the fiber contact side, and wherein the spring force is transferred from the fiber contact side to each of the first and second optical fibers.

24. The apparatus of any of claims 18-20, wherein the pressing member is a beam that traverses the optical coupling reference location and is parallel to the fiber alignment groove, wherein the spring force is provided by a spring, and wherein the spring force is transferred through the beam to the first and second optical fibers to spring bias the first and second optical fibers into the fiber alignment groove.

25. The apparatus of claim 24, wherein the beam is integrated as part of a metal, ceramic, or plastic component.

26. The apparatus of claim 24, wherein the beam is configured to engage both the first and second optical fibers directly at tips of the first and second optical fibers.

27. The apparatus of any of claims 18-20, wherein the fiber alignment member defines a plurality of the fiber alignment grooves and the apparatus includes a plurality of the pressing members.

28. The apparatus of claim 27, wherein the fiber alignment grooves are parallel, and wherein each pressing member corresponds to no more than two of the fiber alignment grooves.

29. An apparatus for co-axially aligning first and second optical fibers to provide an optical coupling between the first and second optical fibers, the apparatus comprising: a fiber alignment substrate defining a fiber alignment groove for receiving the first and second optical fibers, the fiber alignment groove defining a fiber insertion axis along which the first and second fibers are moved when inserted into the fiber alignment groove, the apparatus including an optical coupling reference location at which end faces of the first and second optical fibers will oppose one another when the first and second optical fibers are optically coupled together, the optical coupling reference location being positioned along the fiber alignment groove; a pressing member for pressing at least one of the first and second optical fibers into the fiber alignment groove; the fiber alignment groove including a closed side positioned opposite the open side, wherein the fiber alignment groove is defined by first and second fiber alignment surfaces that are angled with respect to one another so as to converge as the first and second alignment surfaces extend in a direction from the open side toward the closed side of the fiber alignment groove, the fiber alignment groove including a fiber receiving region and a gel venting cavity, the fiber receiving region being located between the open side and the gel venting cavity and the gel venting cavity being located at the closed side of the fiber alignment groove, the gel venting cavity being defined between first and second cavity-defining surfaces that extend respectively from the first and second fiber alignment surfaces toward the closed side of the fiber alignment groove, the first and second cavity-defining surfaces being respectively oriented at oblique angles respect to reference planes corresponding to the first and second fiber alignment surfaces; and gel positioned within the fiber receiving region adjacent the optical coupling reference location, wherein when the first and second optical fibers are inserted into the fiber alignment groove at least a portion of the gel is displaced from the fiber receiving region into the gel venting cavity.

30. The apparatus of claim 29, wherein the first and second cavity-defining surfaces converge as the first end second shape-defining surfaces extend toward the closed side at a convergence angle that is less than or equal to one third of a convergence angle of the first and second fiber alignment surfaces.

31. The apparatus of any of claims 29-30, wherein the pressing member is flexible.

32. The apparatus of claim 31, wherein the pressing member is an intermediate force transfer member configured for transferring the spring force from one or more springs to each of the first and second optical fibers.

33. The apparatus of claim 32, wherein the pressing member includes a spring contact side positioned opposite from a fiber contact side, wherein the spring or springs apply the spring force to the spring contact side, wherein the spring force is transferred through the pressing member from the spring contact side to the fiber contact side, and wherein the spring force is transferred from the fiber contact side to each of the first and second optical fibers.

34. The apparatus of any of claims 29-30, wherein the pressing member is a beam that traverses the optical coupling reference location and is parallel to the fiber alignment groove, wherein the spring force is provided by a spring, and wherein the spring force is transferred through the beam to the first and second optical fibers to spring bias the first and second optical fibers into the fiber alignment groove.

35. The apparatus of claim 34, wherein the beam is integrated as part of a metal, ceramic, or plastic component.

36. The apparatus of claim 34, wherein the beam is configured to engage both the first and second optical fibers directly at tips of the first and second optical fibers.

37. The apparatus of any of claims 29-30, wherein the fiber alignment substrate defines a plurality of the fiber alignment grooves and the apparatus includes a plurality of the pressing members.

38. The apparatus of claim 37, wherein the fiber alignment grooves are parallel, and wherein each pressing member corresponds to no more than two of the fiber alignment grooves.