WO2022055771A1

WO2022055771A1 - Mating springs for use with optical connection devices

Info

Publication number: WO2022055771A1
Application number: PCT/US2021/048711
Authority: WO
Inventors: Danny Willy August Verheyden
Original assignee: Commscope Technologies Llc
Priority date: 2020-09-14
Filing date: 2021-09-01
Publication date: 2022-03-17

Abstract

The present disclosure relates generally to an optical connection device that can include a fiber holder and a plurality of optical fibers supported by the fiber holder. The optical connection device can also include at least one elongate, non-coiled spring mounted at the second end of the fiber holder that has a length that extends across a width of the fiber holder. Exposed ends of the at least one elongate, non-coiled spring can be configured to flex when the fiber holder is mated with another fiber holder such that the fiber holders are biased toward each other to maintain physical contact between end faces of the optical fibers held by the fiber holders.

Description

MATING SPRINGS FOR USE WITH OPTICAL CONNECTION DEVICES

Cross-Reference to Related Applications

This application is being filed on September 1, 2021, as a PCT International Patent Application and claims the benefit of U.S. Patent Application Serial No. 63/078,037, filed on September 14, 2020, the disclosure of which is incorporated herein by reference in its entirety.

Technical Field

The present disclosure relates generally to multi-fiber connectivity. More particularly, the present disclosure relates to a mating spring for an optical fiber connector system.

Background

Fiber optic connectors are commonly used in optical fiber communication systems to effect demateable optical connections between waveguides such as optical fibers. A typical optical connection is made by co-axially aligning two optical fibers in end-to-end relation with end faces of the optical fibers opposing one another. To effect optical coupling and minimize Fresnel loss, it is typically preferred for “physical contact” to exist between the optical waveguides, which, in the case of optical connectors, is generally between the opposed end faces of the aligned optical fibers.

Fiber optical adapters are used to optically couple together optical fiber tips of optical connectors. In the case of ferrule-less fiber optical connection systems (i.e. , bare fiber fiber optic connection systems), fiber optic 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. In the case of ferruled fiber optic connection systems, fiber optic adapters can be configured to receive and align ferrules which support optical fibers to achieve alignment between the optical fibers. In some fiber optic connection systems, fiber alignment is achieved by intermating portions of fiber optic connectors being coupled together (e.g., MPO type connection systems employ pin and socket alignment arrangements). With the increase in data demand, higher fiber count cables are being used to service customers. It is desirable to have connector components that can accommodate higher fiber counts while also complying with size restrictions of ducting systems.

Summary

The present disclosure relates generally to a multi-fiber connection system that includes a biasing component for biasing optical fibers of two fiber optic connectors together when the two fiber optic connectors are coupled together (e.g., either directly or through an intermediate fiber optic adapter). The biasing component can be an elongate structural member such as a rod-shaped member. It will be appreciated that the rodshaped member may have a round, square, oval or other cross-sectional shape. The biasing component of the fiber optical connectors can be used with alignment devices and connector components that are sized to improve the mobility of high fiber count cables in ducting systems. In certain examples, the biasing components can be configured to facilitate manufacturing compact fiber optic connectors. In certain examples, the biasing components can facilitate the cost effective manufacture of fiber optic connectors.

As used herein, the term “optical fiber” relates to an optical transmission element. In certain examples, the optical fiber can have a core size between 8-12 micrometers in outer diameter, a cladding layer with an outer diameter of 120-130 micrometers, and a coating layer with an outer diameter of 250 micrometers. The optical fibers can include ribbonized portions and bare fiber portions (i.e., no coating layer). The low-profile fiber holder provides a desired pitch for optical fibers routed therethrough in preparation for bare fiber connectivity. In certain examples, the pitch is 200 micrometers. In other examples, the pitch is 250 micrometers.

One aspect of the present disclosure relates to an optical connection device. The optical connection device can include a fiber holder that has a length that extends between first and second ends of the fiber holder and a width that extends between first and second sides of the fiber holder. The optical connection device can include a plurality of optical fibers supported by the fiber holder. The plurality of optical fibers can extend through the fiber holder from the first end to the second end and have fiber ends that are accessible at the first end of the fiber holder. The optical connection device can also include at least one elongate, non-coiled spring mounted at the second end of the fiber holder. The at least one elongate, non-coiled spring has a length that extends across the width of the fiber holder. Exposed ends of the at least one elongate, non-coiled spring can be configured to flex when the fiber holder is mated with another fiber holder such that ends of the optical fibers held by the fiber holders are biased together to maintain physical contact between the ends of the optical fibers held by the fiber holders.

These and other features and advantages will be apparent from a reading of the following detailed description and a review of the associated drawings. A variety of additional aspects will be set forth in the description that follows. These 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 concepts upon which the embodiments 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. 1 illustrates a first embodiment of a multi-fiber optical connector system including a cable, a connector body, and a dust cap in accordance with the principles of the present disclosure.

FIG. 2 illustrates the multi-fiber optical connector system of FIG. 1 with the dust cap removed showing a plurality of fiber holders within the connector body in accordance with the principles of the present disclosure.

FIG. 3 illustrates an enlarged view of a portion of the multi-fiber optical connector system of FIG. 2.

FIG. 4 illustrates the multi-fiber optical connector system of FIG. 3 showing a cover of the connector body removed.

FIGS. 5-6 illustrate multiple perspective views of one of the fiber holders of FIG. 2 showing fiber ends of a plurality of optical fibers projecting slightly from an end face of the fiber holder.

FIG. 7 illustrates a side view of the fiber holder of FIGS. 5-6.

FIG. 8 illustrates a perspective view of the fiber holder of FIG. 5 showing bare fibers extending from the end face of the fiber holder.

FIG. 9 illustrates an exploded view of the multi-fiber optical connector system of FIG. 5. FIGS. 10-13 illustrate perspective views of first and second fiber holder pieces of the fiber holder of FIG. 5 in accordance with the principles of the present disclosure.

FIG. 14 illustrates an exploded perspective view of the multi -fiber optical connector system of FIG. 1 with the cable removed.

FIG. 15 illustrates atop view of the multi -fiber optical connector system of FIG. 4 showing a biasing component mounted to the fiber holder in accordance with the principles of the present disclosure.

FIG. 16 illustrates the multi-fiber optical connector system of FIG. 15 showing the biasing component flexed in accordance with the principles of the present disclosure.

FIG. 17 illustrates a schematic top view of two connectors mated together inside a multi-fiber adapter in accordance with the principles of the present disclosure.

Detailed Description

Reference will now be made in detail to the exemplary aspects of the present disclosure that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like structure.

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.

FIG. 1 depicts a multi-fiber optical connector system 10 in accordance with the principles of the present disclosure shown with a cable 12, a connector 14, and an example dust cap 16.

Turning to FIGS. 2-4, the multi -fiber optical connector system 10 includes multiple optical connection devices 18 stacked together within the connector 14. In the example shown, six optical connection devices 18 are stacked together, although alternatives are possible. Each one of the optical connection devices 18 includes a plurality of optical fibers 20 that may be ribbonized, buffered, or otherwise contained within a passage of an outer jacket 22 of the cable 12. In certain examples, the optical fibers 20 can be arranged in parallel relationship to form a ribbon. It will be appreciated that ribbons of different configuration may be used. As depicted, the optical connection devices 18 each include twenty-four optical fibers 20 to provide a 144 optical fiber count cable 12. In certain examples, however, the cable 12 may include a greater or lesser number of optical fibers 18 (e.g., twenty-four, thirty-six, seventy-two, two hundred eightyeight etc.). Each of the optical fibers 20 has a core and a cladding.

The connector 14 includes a body 13 (e.g., a base, a bottom) that has a front end 26 and an opposite rear end 28. The body 13 defines a longitudinal axis 15 that extends through the body 13 in an orientation that extends from the front end 26 to the rear end 28 of the body 13. The base defines a receptacle 24 that extends between the front and rear ends 26, 28. The receptacle 24 is designed to hold multiple optical connection devices 18 stacked together. A cover 30 (e.g., atop) can be configured to close the receptacle 24 of the connector 14. The cover 30 can include snap fit latches 32 that are provided at opposing sides 34, 36 (see FIG. 14) of the cover 30. The cover 30 can be retained to the connector 14 by a snap-fit connection, a press-fit connection, an adhesive connection or other type of connection. For example, when the cover 30 is mounted to the connector 14, the snap fit latches 30 can engage the catches 38 defined in the connector 14. The catches 38 can be provided in recesses 40 defined in first and second side walls 42, 44 of the connector 14.

Turning to FIGS. 5-7, the optical connection device 18 is depicted. The optical connection device 18 includes a fiber holder 46 that has a first end 48, an opposite second end 50, a top side 52, an opposite, bottom side 54, a first side 56, and an opposite second side 58. The fiber holder 46 has a length L that extends between the first and second ends 48, 50 of the fiber holder 46 and a width W that extends between the first and second sides 56, 58 of the fiber holder 46.

The plurality of optical fibers 20 are shown routed through the fiber holder 46 from the first end 48 to the second end 50. The optical fibers 20 can enter the fiber holder 46 at the second end 50 such that bare fiber ends 60 are positioned adjacent the first end 48 of the fiber holder 46. In certain examples, the plurality of optical fibers 20 have bare fiber portions 64 having bare fiber ends 60 that are accessible at the first end 48 of the fiber holder 46. In the depicted examples of FIGS. 5-7, the bare fiber portions 64 project slightly from the first end of the fiber holder 46, but in alternative examples could be flush or slightly recessed relative to the first end 48. In examples in which the optical fibers 20 are recessed, flush, or protrude only slightly from the first end 48 of the fiber holder 46, fiber alignment can be achieved indirectly via relative positioning and alignment of the fiber holders 46. The optical fibers 20 are shown in place within the fiber holder 46. In certain examples as depicted by FIG. 8, the bare fiber portions 64 (e.g., fiber portions with only a core and cladding) extend a substantial distance beyond the first end 48 of the fiber holder 46. In certain examples, the bare fiber portions 64 project at least 2, 3, 4, 5 or 6 millimeters beyond the end face 62 of the fiber holder 46, although alternatives are possible. Thus, the bare fiber portions 64 are configured to be received within a bare fiber alignment system (e.g., within a fiber optic adapter) that may include grooves or other structures adapted for directly contacting the bare fiber portions 64 to provide alignment with bare fiber portions 64 of another connector.

The optical fibers 20 may be spaced apart to define a gap between each optical fiber 20 making a pitch (i.e., center to center spacing). Example pitches include 250 micrometers and 200 micrometers. The fiber holder 46 can establish a distance from a point on one optical fiber to a corresponding point on an adjacent optical fiber as measured across a horizontal axis between adjacent optical fibers in the fiber holder 46. The fiber holder 46 has a low-profile, compact configuration.

The fiber holder 46 can include a first holder piece 66 and a second holder piece 68 formed by a molding process. In other examples, the fiber holder 46 can include a one-piece body formed by a molding process. The first and second holder pieces 66, 68 together form an enclosed area for supporting the optical fibers 20. The first and second holder pieces can be connected together by a snap-fit connection, a press-fit connection, an adhesive connection or other type of connection.

Turning to FIGS. 9-13, the first and second holder pieces 66, 68 each include pegs 70 that are configured to engage respective openings 72 defined in the first and second holder pieces 66, 68 to mount the first and second holder pieces 66, 68 together. The first and second holder pieces 66, 68 each include a plurality of fiber positioning grooves 74 (e.g., fiber receiving grooves). The fiber positioning grooves 74 may include V-grooves, U-shaped grooves or half rounds or other shapes of grooves.

When the first and second holder pieces 66, 68 are mated together with the optical fibers 20 retained within the plurality of fiber positioning grooves 74, top sides 76 (see FIG. 7) of the bare fiber portions 64 of the optical fibers 20 are engaged with a fiber engagement surface 78 of the plurality of fiber positioning grooves 74 defined in the second holder piece 68 and bottom sides 80 (see FIG. 7) of the bare fiber portions 64 of the optical fibers 20 are engaged with a fiber engagement surface 82 of the plurality of fiber positioning grooves 74 defined in the first holder piece 66. The first holder piece 66 can include a fiber anchoring region 84 (e.g., fiber mating region) adjacent the second end 50. The fiber anchoring region 84 can be provided for securing the optical fibers 20 to the fiber holder 46 with adhesive (e.g., epoxy). The fiber anchoring region 84 can include a non-grooved section 86 for receiving coated portions 88 of the optical fibers 20 and a grooved portion 90 that extends from the nongrooved portion 86 to a cross-channel 92 that functions as an epoxy stop. The plurality of fiber positioning grooves 74 can extend from the cross-channel 92 to the first end 48. The grooved portion 90 can also receive the bare fiber portions 64 of the optical fibers 20.

The second holder piece 68 can include a port 94 for injecting epoxy into the fiber anchoring region 84 once the second holder piece 68 has been mounted to the first holder piece 66 for securing the optical fibers 20 to the fiber holder 46. A recess 96 can be provided in a fiber anchoring region 98 of the second holder piece 68. The recess 96 can surround the port 94 and encourage the flow of epoxy throughout the fiber anchoring region 98. When the first and second holder pieces 66, 68 are mated together, the fiber anchoring region 98 of the second holder piece 68 opposes the fiber anchoring region 84 of the first holder piece 66 such that the fiber anchoring regions 84, 98 cooperate together to secure the optical fibers 20 between the first and second holder pieces 66, 68.

The first and second holder pieces 66, 68 can each include an extension member 100 that extends outwardly from the second end 50 of the fiber holder 46. In certain examples, the extension member 100 can be made integral (e.g., unitary) with the fiber holder 46, although alternatives are possible. The extension member 100 can define a slot 102 that extends along a width Wi (see FIG. 9) of the extension member 100 between first and second sides 104, 106 thereof. Each of the extension members 100 define an elongated through-hole 108 centrally positioned between the first and second sides 104, 106 of the extension member 100. In certain examples, the slot 102 of the extension member 100 can be defined on opposing sides of the elongated through-hole 108. The slot 102 can function as a lead-in into the elongated through-hole 108 and an exit from the elongated through-hole 108. When the first and second holder pieces 66, 68 are mated together, the slot 102 of the extension member 100 of the first holder piece 66 faces downwardly in a direction Di (see FIG. 7) and the slot 102 of the extension member 100 of the second holder piece 68 faces upwardly in a direction D2 (see FIG. 7) such that the slots 102 oppose one another.

Turning again to FIG. 9, the optical connection device 18 can include at least one biasing component 110 mounted at the second end 50 of the fiber holder 46 for biasing the fiber holder 46 when mated with another fiber holder 46 (e.g., inside an adapter). In certain examples, the optical connection device 18 can include two biasing components 110 mounted at the second end 50 of the fiber holder 46.

In certain examples, the biasing component 110 may be an elongated, straight structure, although alternatives are possible. In certain examples, the biasing component 110 can be an elongate, non-coiled spring that has a length Li (see FIG. 9) that extends across the width W of the fiber holder 46. In certain examples, the biasing component 110 is a rod-shaped spring, although alternatives are possible. The biasing component 110 may have a round, square, oval, cylindrical or other shaped cross-section.

Turning to FIGS. 14-16, the biasing component 110 can be mounted at the second end 50 of the fiber holder 46 and extend laterally across the width W of the fiber holder 46. The biasing component 110 can be inserted into the slot 102 of the extension member 100 and through the elongated through-hole 108 of the extension member 100 such that exposed ends 112 of the biasing component 110 extend from opposing sides of the extension member 100. That is, except for the exposed ends 112, the remaining parts of the biasing component 110 is supported within the elongated through-hole 108 and the slots 102. In certain examples, the biasing component 110 can slide into the slot 102 from one of the first and second sides 56, 58 of the fiber holder 46 to enter through the elongated through-hole 108. In certain examples, the biasing component 110 can be overmolded into the elongated through-hole 108 of the extension member 100.

The dust cap 16 mounts over the connector 14 to seal the fiber holder 46 and thereby shield and protect polished ends of the bare fiber ends 60 from contamination. The dust cap 16 includes a sleeve 114 that has a closed end 116 and an open end 118 that mounts over the connector 14. The dust cap 16 can include major sides 120 and minor sides 122. A latch 124 can be provided on the minor sides 122 of the dust cap 16. In certain examples, the latch 124 is integrally formed with the sleeve 114 of the dust cap 16, although alternatives are possible. The latch 124 includes a projection 126 that extends beyond the open end 118 of the sleeve 114 of the dust cap 16. The projection 126 is configured to engage recess 128 defined in the body 13 of the connector 14 to form a snap-fit connection between the dust cap 12 and the connector 14. As such, the latch 124 releasably latches the dust cap 16 on the body 13 of the connector 14.

Turning to FIG. 17, an optical fiber connection system 130 is schematically depicted. The connector 14 is shown inserted into a first adapter port 132 of a multi-fiber fiber optic adapter 134 and a second connector 14a is shown inserted into a second adapter port 136 of the multi -fiber fiber optic adapter 134. It will be appreciated that the multifiber fiber optic adapter 134 is adapted to receive optical fibers that are not supported by or secured within a ferrule.

The multi-fiber fiber optic adapter 134 can include an alignment device 138 configured to receive and align the fiber holders 46 stacked within respective first and second connectors 14, 14a. The optical fibers 20 project slightly from the first ends 48 of the fiber holders 46 such that the alignment device 138 does not directly contact the optical fibers 20 when the fiber holders 46 are aligned. As such, fiber alignment can be achieved indirectly via relative positioning and alignment of the fiber holders 46 within the alignment device 138. By aligning the fiber holders 46 within the alignment device 138, the bare fiber portions 64 of the plurality of optical fibers 20 can be co-axially aligned such that optical signals can be conveyed between the plurality of optical fibers 20 held by the fiber holders 46 of the connectors 14, 14a, respectively.

The connectors 14, 14a can each include latches 140 (see FIG. 15) and the multi-fiber fiber optic adapter 134 can define notched sections (not shown) that the latches 140 of the connectors 14, 14a engage as part of a latching arrangement to allow the connectors 14, 14a to be secured (e.g., interlocked) within mating first and second adapter ports 132, 136 of the multi-fiber fiber optic adapter 134, respectively, such that the optical fibers 20 of the respective connectors 14, 14a abut against one another. The exposed ends 112 of the biasing component 110 are configured to flex or bend (see FIG. 16) to allow continuous insertion of the connectors 14, 14a into respective first and second adapter ports 132, 136 until the latches 140 engage the notched sections of the multi-fiber fiber optic adapter 13. The exposed ends 112 of the biasing component 110 are not configured to flex or bend until two fiber holders 46 are mated together.

When the connectors 14, 14a are mated together in the multi -fiber fiber optic adapter 134 contact between end faces 62 of the fiber holders 46 of the connectors 14, 14a causes relative movement between the connector bodies 13 and the fiber holders 46 which results in retraction of the fiber holders 46 lengthwise along the longitudinal axis 15 in a direction Ds. As the fiber holders 46 retract, contact between the exposed ends 112 of the biasing components 110 and shoulders 142 (see FIG. 14) defined within the connector bodies 13 causes the biasing components 110 to flex and apply spring load to the fiber holders 46 that biases the fiber holders 46 of the mated connectors 14, 14a in a direction D4 toward one another. Thus, spring force F biases the end faces 62 of the fiber holders 46 toward one another to maintain face-to-face contact between the optical fibers 20 held by the fiber holders 46. The latches 140 hold the connector bodies 13 in positions within the multi -fiber fiber optic adapter 134 such that the spring load on the fiber holders 46 is maintained.

In certain examples, two fiber holders 46 can be mated together in the multi-fiber fiber optic adapter 134 to optically couple bare fibers together that are not housed in a connector body.

From the forgoing detailed description, it will be evident that modifications and variations can be made without departing from the spirit and scope of the disclosure.

Claims

What is claimed is:

1. An optical connection device, comprising: a fiber holder having a length that extends between first and second ends of the fiber holder and a width that extends between first and second sides of the fiber holder; a plurality of optical fibers supported by the fiber holder, the plurality of optical fibers extending through the fiber holder from the first end to the second end, the plurality of optical fibers having fiber ends accessible at the first end of the fiber holder; and at least one elongate, non-coiled spring mounted at the second end of the fiber holder, the at least one elongate, non-coiled spring having a length that extends across the width of the fiber holder; wherein exposed ends of the at least one elongate, non-coiled spring are configured to flex when the fiber holder is mated with another fiber holder such that ends of the optical fibers held by the fiber holders are biased together.

2. The optical connection device of claim 1, wherein the fiber holder is formed by first and second holder pieces.

3. The optical connection device of claim 2, further comprising an extension member that extends outwardly from the second end of the fiber holder, the extension member defining opposing slots.

4. The optical connection device of claim 3, wherein the at least one elongate, non-coiled spring is positioned within the slots of the extension member.

5. The optical connection device of claim 2, wherein the first and second holder pieces each include an elongate, non-coiled spring mounted at second ends thereof.

6. The optical connection device of claim 1, wherein the fiber holder defines a plurality of fiber positioning grooves extending partially along the length of the fiber holder.

7. The optical connection device of claim 2, wherein the first holder piece is mounted to the second holder piece by a press-fit connection or a snap-fit connection.

8. The optical connection device of claim 7, wherein the first holder piece is a top part and the second holder piece is a bottom part.

9. The optical connection device of claim 8, wherein the bottom part includes a fiber anchoring region adjacent the second end of the fiber holder, the fiber anchoring region having a cross-channel that functions as an epoxy stop.

10. The optical connection device of claim 9, wherein the fiber anchoring region includes a non-grooved section for receiving coated portions of the plurality of optical fibers and a grooved section that extends from the non-grooved section.

11. The optical connection device of claim 8, wherein the top part defines at least one epoxy injection port for receiving epoxy to secure the plurality of optical fibers routed through the fiber holder.

12. An optical fiber connection system comprising: first and second fiber holders each including: a main body having a front end and a rear end, the main body defining a longitudinal axis that extends through the main body in an orientation that extends from the front end to the rear end of the main body; a plurality of optical fibers extending through the main body from the rear end to the front end, the plurality of optical fibers having fiber ends accessible at the front end of the main body; and at least one elongate, non-coiled spring mounted at the rear end of the main body, the at least one elongate, non-coiled spring having a length that extends across the main body perpendicular to the longitudinal axis; a multi-fiber adapter defining first and second adapter ports for respectively receiving the first and second fiber holders to couple the first and second fiber holders together; wherein, when the first and second fiber holders are coupled together inside the multi-fiber adapter, exposed ends of the at least one elongate, non-coiled springs are configured to flex such that the plurality of optical fibers of the first and second fiber holders are biased together.

13. The optical fiber connection system of claim 12, further comprising an extension member that extends outwardly from the rear end of the main body of the first and second fiber holders, the extension member defining a slot.

14. The optical fiber connection system of claim 13, wherein the at least one elongate, non-coiled spring of the first and second fiber holders is positioned within the slot of the extension member such that the exposed ends of the at least one elongate, noncoiled spring extend outwardly at first and second sides of the main body, respectively.

15. The optical fiber connection system of claim 12, further comprising first and second plug housings, the first and second plug housings each defining a receptacle for receiving the first and second fiber holders.

16. The optical fiber connection system of claim 15, wherein, when the first and second fiber holders are mated together, the first and second plug housings are configured to slide lengthwise along the longitudinal axis such that the at least one elongate, non-coiled spring is pressed against a respective shoulder defined within the first and second plug housings.

17. The optical fiber connection system of claim 16, wherein the first and second plug housings each including a cover and a base.

18. The optical fiber connection system of claim 15, further comprising a stack of first fiber holders positioned inside the first plug housing and a stack of second fiber holders positioned inside the second plug housing.

19. The optical fiber connection system of claim 18, wherein each of the first and second fiber holders include a first holder piece, a second holder piece, and a fiber mating region between the first and second holder pieces.

20. The optical fiber connection system of claim 15, further comprising a latching arrangement for securing the first and second plug housings respectively in the first and second adapter ports of the multi-fiber adapter.

21. The optical fiber connection system of claim 17, wherein the cover and the base of the first and second plug housings are connected together by a snap-fit connection.

22. The optical fiber connection system of claim 12, wherein the fiber ends are flush with end faces of the main bodies of the first and second fiber holders.

23. The optical fiber connection system of claim 12, wherein the fiber ends protrude outwardly from the front ends of the main bodies of the first and second fiber holders.

24. The optical fiber connection system of claim 15, further comprising a dust cap mounted at a front end of each of the first and second plug housings.

25. The optical fiber connection system of claim 12, wherein the multi-fiber adapter has multiple fiber alignment grooves for receiving and co-axially aligning the fiber ends of the plurality of optical fibers such that optical signals can be conveyed between the plurality of optical fibers of the first and second fiber holders.

26. A multi-fiber bare fiber connection system comprising: a plug housing defining a receptacle that extends between a front end of the plug housing and a rear end of the plug housing; and multiple fiber holders stacked together, the multiple fiber holders being mounted within the receptacle of the plug housing, each one of the multiple fiber holders having a length that extends between first and second ends of the fiber holders and a width that extends between first and second sides of the fiber holders, the multiple fiber holders each including: a plurality of optical fibers supported by the fiber holder, the plurality of optical fibers extending through the fiber holder from the first end to the second end, the plurality of optical fibers having fiber ends accessible at the first end of the fiber holder; and at least one elongate, non-coiled spring mounted at the second end of the fiber holder, the at least one non-coiled spring having a length that extends laterally across the width of the fiber holder; wherein exposed ends of the at least one elongate, non-coiled spring are configured to flex when the plug housing is mated with another plug housing such that the multiple fiber holders of the mated plug housings are biased toward one another to maintain physical contact between end faces of the plurality of optical fibers held by the fiber holders.

27. The multi-fiber bare fiber connection system of claim 26, wherein the first ends of the multiple fiber holders extend beyond the front end of the plug housing.

28. The multi-fiber bare fiber connection system of claim 26, further comprising an extension member that extends outwardly from the second ends of the multiple fiber holders, the extension member defining slots.

29. The multi-fiber bare fiber connection system of claim 28, wherein the at least one elongate, non-coiled springs are positioned within the slots of the extension member such that the exposed ends of the at least one elongate, non-coiled springs extend outwardly at the first and second sides of the fiber holders, wherein the exposed ends of the at least one elongate, non-coiled springs are configured to flex against shoulders defined within the receptacle of the plug housing.

30. The multi-fiber bare fiber connection system of claim 26, wherein the fiber ends of the plurality of optical fibers are flush with respective end faces of the multiple fiber holders.

31. The multi-fiber bare fiber connection system of claim 26, wherein the fiber ends of the plurality of optical fibers protrude outwardly from respective end faces of the multiple fiber holders.