An optical fiber ribbon with bond portions providing flexibility and reduced stress between bonded optical fibers

Abstract

An optical fiber ribbon with bond portions structurally configured provide enhanced flexibility to the ribbon and reduced stress between bonded optical fibers. The ribbon may include a first optical fiber bonded to a second optical fiber along a longitudinal direction of the first optical fiber by a bond portion. The ribbon may include a first location on the first optical fiber where the first optical fiber is closest to the second optical fiber and a first cross-sectional area between the first optical fiber and the second optical fiber and between the first location and a first line tangent to outer surfaces of both the first optical fiber and the second optical fiber. The bond portion may be located in the first area but not fully fill the first area.

Description

AN OPTICAL FIBER RIBBON WITH BOND PORTIONS PROVIDING FLEXIBILITYAND REDUCED STRESS BETWEEN BONDED OPTICAL FIBERSCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 651 ,574 filed May 24, 2024, which is currently pending, the disclosure of which is hereby incorporated by reference herein in its entirety.TECHNICAL FIELD

[0002] The present disclosure relates generally to optical fibers. More particularly, the present disclosure relates to bonding multiple optical fibers together in a ribbon with bonds structurally configured to provide enhanced flexibility of the ribbon and reduced stress between bonded optical fibers.BACKGROUND

[0003] The evolution of 5G and increase of data consumption over recent years have drastically increased the application of data centers and Telecoms. Large scale data centers and Telecom sectors require ultra-high fiber density cables that offer high data rate with low latency. High fiber density cables can include a large number of optical fibers inside the cable. Optical fiber ribbons, including traditional flat ribbons where the ribbon is fully encapsulated in a ribbon matrix and flexible ribbons where fibers are intermittently bonded with a ribbon matrix, are highly preferred over loose fibers for high fiber count cables because they provide significant reduction in installation time thanks to the use of mass fusion splicing. Flat ribbons have preferential bending in one direction which limits the fiber packing density in a cable. Flexible ribbons, however, are packed more efficiently in a cable as they can fold to reach a similar density of loose fiber in large diameter tube or subunit. Additionally, a single flexible ribbon in a small form factor cable or subunit typically has limited capability to coil or fold within itself and can induce stresses on thefibers. Some 2.0 mm small form factor flexible ribbon cables utilize single mode fiber (SMF), with multi mode fiber (MMF) typically not offered because of the increased stress sensitivity.

[0004] Therefore, it may be desirable to provide an optical fiber ribbon that includes optical fibers that are intermittently bonded by a bond portion structurally configured to provide reduced stress between bonded optical fibers while permitting the bonded optical fibers to move relative to each other to facilitate bending of the optical fiber ribbon in a transverse direction.SUMMARY

[0005] According to various exemplary aspects of the disclosure, an optical fiber with bond portions structurally configured provide enhanced flexibility to the ribbon and reduced stress between bonded optical fibers is disclosed. In some embodiments, the optical fiber ribbon may include a first optical fiber bonded to a second optical fiber along a longitudinal direction of the first optical fiber by a bond portion.

[0006] In some embodiments, a first location on the first optical fiber may be a location at which the first optical fiber is closest to the second optical fiber. In some embodiments, a first area may be defined as a first cross-sectional area between the first optical fiber and the second optical fiber, and between the first location on the first optical fiber and a first line tangent to outer surfaces of both the first optical fiber and the second optical fiber. In some embodiments, the first area may include a proximal area adjacent the first location and a distal area adjacent the first line.

[0007] In some embodiments, the bond portion may be located in the first area but not fully fill the first area. In some embodiments, the bond portion may not be located along a transverse line within one of the proximal area or the distal area, wherein the transverse line extends perpendicular from the first line through the first location.

[0008] In some embodiments, the bond portion may provide reduced stress between the first optical fiber and the second optical fiber while permitting the first opticalfiber to move relative to the second optical fiber to facilitate bending of the ribbon in a transverse direction.

[0009] In some embodiments, the first optical fiber may include a glass core inside a first protective coating system, the second optical fiber may include a second glass core inside a second protective coating system, and the first line may be tangent to an outer surface of the first protective coating system and an outer surface of the second protective coating system.

[0010] In some embodiments, the bond portion may include a distal surface portion and a proximal surface portion opposite the distal surface portion, wherein the proximal surface portion is spaced apart from the first point by a portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber.

[0011] In some embodiments, the bond portion may include a first bonding portion configured to bond to the first optical fiber, a second bonding portion configured to bond to the second optical fiber, and an intermediate portion between the first bonding portion and the second bonding portion, and wherein intermediate portion has a cross- sectional area that is smaller than a cross-sectional area of at least one of the first bonding portion and the second bonding portion.

[0012] In some embodiments, at least one of the distal surface portion or the proximal surface portion may include a concave portion in the intermediate portion.

[0013] In some embodiments, the cross sectional area of the intermediate portion may be uniform for at least 50% of a distance between the first bonding portion and the second bonding portion.

[0014] In some embodiments, the portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber may include a non-bonding material configured to function as a bedding material for the bond portion.

[0015] In some embodiments, the bond portion may have a V-shaped cross- sectional shape.

[0016] In some embodiments, the first area may have a height measured from the first point to the first line and the bond portion may fully fill the first area below adistance that is in the range of 30% to 60% of the height and the bond may be bifurcated beyond the distance.

[0017] In some embodiments, the bond portion may be a first bond portion of a plurality of bond portions, and the second optical fiber may be intermittently bonded to the first optical fiber by the plurality of bond portions.

[0018] In some embodiments, the bond portion may extend to the first line.

[0019] In some embodiments, the bond portion may be a first bond portion and the optical fiber ribbon may include a second bond portion having a different cross- sectional shape than a cross-sectional shape of the first bond portion.

[0020] In some embodiments, the first bond portion may be a first bond portion of a plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber and the second bond portion may be second bond portion of the plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber.

[0021] In some embodiments, an optical fiber ribbon may include bond portions structurally configured to provide enhanced flexibility to the ribbon and reduced stress between bonded optical fibers. In some embodiments, the optical fiber ribbon may include a first optical fiber and a second optical fiber bonded to the first optical fiber along a longitudinal direction of the first optical fiber by a bond portion.

[0022] In some embodiments, the bond portion may be a first bond portion of a plurality of bond portions and the second fiber may be intermittently bonded to the first fiber by the plurality of bond portions.

[0023] In some embodiments, a first location on the first optical fiber may be a location at which the first optical fiber is closest to the second optical fiber;

[0024] In some embodiments, a first area may be defined as a first cross- sectional area between the first optical fiber and the second optical fiber, and between the first location on the first optical fiber and a first line tangent to outer surfaces of both the first optical fiber and the second optical fiber.

[0025] In some embodiments, a first area may include a proximal area adjacent the first location and a distal area adjacent the first line.

[0026] In some embodiments, the first cross-sectional area may be in a cross- sectional plane perpendicular to the longitudinal direction of the first optical fiber.

[0027] In some embodiments, the bond portion may be located in the first area and the bond portion may not be located along a transverse line within one of the proximal area or the distal area, wherein the transverse line extends perpendicular from the first line through the first location.

[0028] In some embodiments, the bond portion may provide a reduced stress between the first optical fiber and the second optical fiber while permitting the first optical fiber to move relative to the second optical fiber to facilitate bending of the ribbon in a transverse direction.

[0029] In some embodiments, the bond portion may include a distal surface portion and a proximal surface portion opposite the distal surface portion. In some embodiments, the proximal surface portion may be spaced apart from the first point by a portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber.

[0030] In some embodiments, the bond portion may include a first bonding portion configured to bond to the first optical fiber, a second bonding portion configured to bond to the second optical fiber, and an intermediate portion between the first bonding portion and the second bonding portion. In some embodiments, the intermediate portion may have a cross-sectional area that is smaller than a cross-sectional area of at least one of the first bonding portion and the second bonding portion.

[0031] In some embodiments, at least one of the distal surface portion or the proximal surface portion may include a concave portion in the intermediate portion.

[0032] In some embodiments, the cross-sectional area of the intermediate portion may be uniform for at least 50% of a distance between the first bonding portion and the second bonding portion.

[0033] In some embodiments, the portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber may include a non-bonding material configured to provide a bedding for the bond portion.

[0034] In some embodiments, the bond portion may have a V-shaped cross- sectional shape.

[0035] In some embodiments, the first area may have a height measured from the first point to the first line and the bond portion may fully fill the first area below a distance that is in the range of 30% to 60% of the height and the bond is bifurcated beyond the distance.

[0036] In some embodiments, the bond portion may extend to the first line.

[0037] In some embodiments, the bond portion may not extend to the first line.

[0038] In some embodiments, the bond may be a first bond and the optical fiber ribbon may include a second bond portion having a different cross-sectional shape than a cross-sectional shape of the first bond portion.

[0039] In some embodiments, the second bond portion may be a second bond portion of the plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber.

[0040] In some embodiments, an optical fiber ribbon may include bond portions structurally configured to provide enhanced flexibility to the ribbon and reduced stress between bonded optical fibers. In some embodiments, the bond portion may include a first optical fiber and a second optical fiber bonded to the first optical fiber along a longitudinal direction of the first optical fiber by a bond portion.

[0041] In some embodiments, a first location on the first optical fiber may be a location at which the first optical fiber is closest to the second optical fiber. In some embodiments, a first area may be defined as a first cross-sectional area between the first optical fiber and the second optical fiber, and between the first location on the first optical fiber and a first line tangent to outer surfaces of both the first optical fiber and the second optical fiber.

[0042] In some embodiments, the first area may include a proximal area adjacent the first location and a distal area adjacent the first line.

[0043] In some embodiments, the first optical fiber may include glass core inside a first protective coating system and the second optical fiber may include a second glasscore inside a second protective coating system. In some embodiments, the first line may be tangent to an outer surface of the first protective coating system and an outer surface of the second protective coating system.

[0044] In some embodiments, the bond portion may be located in the first area and the bond portion may not be located along a transverse line within one of the proximal area or the distal area, where the transverse line extends perpendicular from the first line through the first location.

[0045] In some embodiments, the bond portion may provide reduced stress between the first optical fiber and the second optical fiber while permitting the first optical fiber to move relative to the second optical fiber to facilitate bending of the ribbon in a transverse direction.

[0046] In some embodiments, the bond portion may include a distal surface portion and a proximal surface portion opposite the distal surface portion. In some embodiments, the proximal surface portion may be spaced apart from the first point by a portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber.

[0047] In some embodiments, the bond portion may include a first bonding portion configured to bond to the first optical fiber, a second bonding portion configured to bond to the second optical fiber, and an intermediate portion between the first bonding portion and the second bonding portion. In some embodiments, the intermediate portion may have a cross-sectional area that is smaller than a cross-sectional area of at least one of the first bonding portion and the second bonding portion.

[0048] In some embodiments, at least one of the distal surface portion or the proximal surface portion may include a concave portion in the intermediate portion.

[0049] In some embodiments, the cross-sectional area of the intermediate portion may be uniform for at least 50% of a distance between the first bonding portion and the second bonding portion.

[0050] In some embodiments, the portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber may include a non-bonding material configured to provide a bedding for the bond portion.

[0051] In some embodiments, the bond portion may have a V shaped cross- sectional shape.

[0052] In some embodiments, the first area may have a height measured from the first point to the first line and the bond portion may fully fill the first area below a distance that is in the range of 30% to 60% of the height and the bond is bifurcated beyond the distance.

[0053] In some embodiments, the bond portion may be a first bond portion of a plurality of bond portions and the second optical fiber may be intermittently bonded to the first fiber by the plurality of bond portions.

[0054] In some embodiments, the bond portion may extend to the first line.

[0055] In some embodiments, the first location may be a point where the first protective coating system contacts the second protective coating system.

[0056] In some embodiments, the bond portion may be a first bond portion and the optical fiber ribbon may include a second bond portion having a different cross- sectional shape than a cross-sectional shape of the first bond portion.

[0057] In some embodiments, the bond portion may be a first bond portion of a plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber and the second bond portion may be a second bond portion of the plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber.

[0058] Various aspects of the connector, as well as other embodiments, objects, features and advantages of this disclosure, will be apparent from the following detailed description of illustrative embodiments thereof, which is to be read in conjunction with the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0059] FIG. 1 is a top view of a ribbon of optical fibers intermittently bonded together.

[0060] FIG. 2 is a sectional view of two optical fibers side-by-side.

[0061] FIG. 3 is a sectional view of a first exemplary fiber bonding.

[0062] FIG. 4 is a sectional view of a second exemplary fiber bonding.

[0063] FIG. 5 is a sectional view of a third exemplary fiber bonding.

[0064] FIG. 6 is a sectional view of a ribbon of optical fibers bonded with the first exemplary fiber bonding of FIG. 3.

[0065] FIG. 7 is a partial sectional view of a ribbon of optical fibers shown in FIG. 6 being subjected to a flexing force.

[0066] FIG. 8 is partial sectional view of a ribbon of optical fibers shown in FIG. 6 being subjected to a flexing force.

[0067] FIG. 9 is a sectional view of a first exemplary fiber bonding of FIG. 3.

[0068] FIG. 10 is a sectional view of a first exemplary fiber bond in accordance with embodiments of the disclosure.

[0069] FIG. 11 is a sectional view of a second exemplary fiber bond in accordance with embodiments of the disclosure.

[0070] FIG. 12 is a sectional view of a third exemplary fiber bond in accordance with embodiments of the disclosure.

[0071] FIG. 13 is a sectional view of a fourth exemplary fiber bond in accordance with embodiments of the disclosure.

[0072] FIG. 14 is a sectional view of a ribbon of optical fibers bonded together with the first exemplary fiber bond of FIG. 10.

[0073] FIG. 15 is a sectional view of two optical fibers bonded together with the first exemplary fiber bond of FIG. 10 in a rest state.

[0074] FIG. 16 is a sectional view of two optical fibers bonded together with the first exemplary fiber bond of FIG. 10 in a partially rotated state.

[0075] FIG. 17 is a sectional view of two optical fibers bonded together with the first exemplary fiber bond of FIG. 10 in a fully rotated state.

[0076] FIG. 18 is a sectional view of the ribbon of FIG. 14 in a rolled state.

[0077] FIG. 19 is a sectional view of the ribbon of FIG. 14 in a rolled state inside a ribbon fiber cable.

[0078] FIG. 20 is a sectional view of a second exemplary fiber bond of FIG. 11 .

[0079] FIG. 21 is a sectional view of a second exemplary fiber bond of FIG. 11 .

[0080] FIG. 22 is a sectional view of a ribbon of optical fibers bonded together with the first exemplary fiber bond of FIG. 10 and the second exemplary fiber bond of FIG. 11 with all bonds on one side of the ribbon.

[0081] FIG. 23 is a magnified portion of FIG. 22.

[0082] FIG. 24 is a sectional view of a ribbon of optical fibers bonded together with the first exemplary fiber bond of FIG. 10 and the second exemplary fiber bond of FIG. 11 with some bonds on both sides of the ribbon.

[0083] FIG. 25 is a top view of a ribbon of optical fibers intermittently bonded together with the first exemplary fiber bond of FIG. 10 and the second exemplary fiber bond of FIG. 11 used to bond two fibers together.

[0084] FIG. 26 is a top view of a ribbon of optical fibers intermittently bonded together with the a single bond having different bond profiles.DETAILED DESCRIPTION OF EMBODIMENTS

[0085] Reference will now be made in detail to presently preferred embodiments and methods of the present disclosure, which constitute the best modes of practicing the present disclosure presently known to the inventors. The figures are not necessarily to scale. It is to be understood, however, that the disclosed embodiments are merely exemplary of the present disclosure that may be embodied in various and alternative forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for any aspect of the present disclosure and / or as arepresentative basis for teaching one skilled in the art to variously employ the present disclosure.

[0086] It is also to be understood that this present disclosure is not limited to the specific embodiments and methods described below, as specific components and / or conditions may, of course, vary. Furthermore, the terminology used herein is used only for the purpose of describing particular embodiments of the present disclosure and is not intended to be limiting in any way.

[0087] It must also be noted that, as used in the specification and the appended claims, the singular form “a,” “an,” and “the” comprise plural referents unless the context clearly indicates otherwise. For example, reference to a component in the singular is intended to comprise a plurality of components.

[0088] Embodiments of the disclosure provide bonding multiple optical fibers together in a ribbon. In some embodiments, the optical fiber ribbon may include one or more bonds that provide reduced stress between a first optical fiber and a second optical fiber while permitting the first optical fiber to move relative to the second optical fiber to facilitate bending of the optical fiber ribbon in a transverse direction. Although embodiments of the disclosure will be discussed using optical fiber cables as an example, embodiments of the disclosure can be applied to other types of cables.

[0089] In some embodiments, the optical fiber ribbon may include a flexible ribbon design that may use intermittent bonds down the length of the optical fibers to form the optical fiber ribbon. In some examples, the bonding material used to bond the optical fibers together may have a low flexural modulus which, when combined in some examples with only intermittent bonding locations, increases the overall rollability or foldability of the optical fiber ribbon.

[0090] While the following examples are directed to intermittently bonded fibers, the principles discussed can also be applied to ribbons in which the fibers are bonded along their entire lengths (not intermittently bonded).

[0091] FIG. 1 shows a ribbon 10 having a plurality of optical fibers 11 bonded together by bond portions 12. In some embodiments, as shown in FIG. 1 , the bondportions 12 may not extend the entire longitudinal length of the optical fibers 11 and are, instead intermittently spaced along the lengths of the optical fibers 11 .

[0092] FIG. 2 illustrates a first optical fiber 110 and a second optical fiber 112 positioned next to the first optical fiber 110. In the illustrated example, the first and second optical fibers 110, 112 are circular. In some embodiments, however, the first and / or the second optical fibers may be other than circular.

[0093] In the illustrated example, the point P1 at which the first optical fiber 110 and the second optical fiber 112 come in contact, or are closest together if not in contact, may be along a centerline CL passing through both of the optical fibers 110, 112. FIG. 1 illustrates a tangent TL extending from point P2 at the outer surfaces the first optical fiber 110 and point P3 at the outer surface of the second optical fiber 112. A first outer surface portion OS1 of the first optical fiber may extend between P1 and P2 and a second outer surface portion OS2 of the second optical fiber 112 may extend between P1 and P3. The first point P1 , the first outer surface portion OS1 , the second outer surface portion OS2, and the tangent line TL between the points P2 and P3 may define a bondable area BA (e.g., a void between the fibers).

[0094] A midline ML or transverse line extending perpendicular from tangent TL to the first point P1 may define a height H of the bondable area BA. A proximal bondable area PBA may be defined by the point P1 and the portions of the first outer surface portion OS1 and the second outer surface portion OS2 between a line L that is parallel with the tangent line TL and passes through a midpoint of the midline ML (i.e. , bisects the midline ML or is half of the height H). A distal bondable area DBA may be defined by the line L, the tangent line TL and the portions of the first outer surface portion OS1 and the second outer surface portion OS2 between the line L and the tangent line TL. The terminology described above regarding FIG. 2 may be used to describe various exemplary embodiments of bonds within the present disclosure.

[0095] Some bonding application techniques may deposit bonding material from the first point P1 where the fibers touch or are closest together (a fiber tangent point between the fibers) to a partial or full fill of the bondable area BA (e.g., the void) betweenthe fibers. For example, FIGS. 3-5 are examples of bond portions 22, 23 that fully fill a bondable area BA between two optical fibers 11 . FIG. 3 illustrates a first bond portion 22 fully filling the bondable area BA (e.g., a void or gap between the optical fibers 11 on one side of the fibers (e.g., an upper side). FIG. 4 illustrates a first bond portion 22 that fully fills a first bondable area BA1 between the optical fibers 11 on a first side of the fibers and a second bond portion 23 fully filling a second bondable area BA2 between the optical fibers 11 on a second side of the fibers opposite the first side. FIG. 5 illustrates a first bond portion 22 fully filling a first bondable area BA1 between the optical fibers 11 on a first side of the fibers and a second bond portion 23 partially filling a second bondable area BA2 between the optical fibers 11 on a second side of the fibers opposite the first side. FIG. 6 illustrates an optical finer ribbon having a plurality of optical fibers 11 (e.g., twelve optical fibers) bonded by bond portions 12 between each adjacent pair of the optical fibers 11 that fully fill a bondable area BA between two optical fibers 11 on one side of the fibers.

[0096] Bonding profiles like those shown in FIGS. 3-6 may limit rotational movement of the fibers relative to each other, even with a low flexural modulus (low resistance to flexing) bonding material. Limited rotational ability can promote microstressing the fibers and / or bond failure. Further, flexible ribbons may require a larger cable ID than cables manufactured with a loose fiber bundle.

[0097] The flexible ribbon performance issues noted above are primarily due to the stretching limitations of the bonding materials, in conjunction with the bonding shape profile and where the bonding matrix adheres to the fibers. Embodiments of the disclosure create alternate bonding design options, with one intent of increased fiber rotational flexibility while inducing less microbend and / or other types of stresses on the fibers. One exemplary design goal is a 2.0 mm ribbon cable (and 2.0 mm subunits for stranded designs) with 12 fiber 250 pm or 16 fiber 200 pm single ribbon options, to be offered in both SMF and MMF versions.

[0098] Some flexible ribbon designs were developed and optimized for multiple ribbons within a single tube, with the intent of increasing fiber density relative to a solid rectangular ribbon stack using traditional flat ribbon design.

[0099] Exemplary embodiments of the disclosure provide flexible ribbon designs that use intermittent bonds down the length of the fibers to form a ribbon. In some embodiments, the bonding material may have a low flexural modulus which, when combined in some examples with only intermittent bonding locations, increases the overall rollability or foldability of the ribbon. Because of the various types of bond profile designs described in these embodiments, medium and high flexural modulus bonding materials are also applicable.

[0100] Embodiments provide an optical fiber ribbon wherein a bond provides reduced stress between a first fiber and a second fiber while permitting the first fiber to move relative to the second fiber to facilitate bending of the ribbon in a transverse direction.

[0101] FIG. 7 illustrates a bending force in the direction of arrows A to bend the ribbon in a direction that rotates the fibers relative to one another such that the bond portions 12 would need to stretch at their upper areas and / or compressed as their lower areas. FIG. 8 illustrates a bending force in the direction of arrows B to bend the ribbon in a direction that rotates the fibers relative to one another such that the bond portions 12 would need to be compressed at their upper areas and / or stretched at their lower areas. Such forces can create stress on the optical fibers 11 as well as promote bond failure. Additionally, a relatively large amount of force can be required to bend such ribbons.

[0102] In some embodiments, the bond profiles between adjacent optical fibers may be configured to address some of the concerns (e.g., limited rotational ability, high stress between bonded optical fibers) associated with bonds like those shown in FIGS. 3-6. One of the bond portions 12 between two of the optical fibers 11 of FIG. 6 is recreated in FIG. 9 for comparison to the exemplary embodiments of bonds illustrated in FIGS. IQ-

[0103] FIG. 10 illustrates an example of a first bond portion 120 between two optical fibers 110, 112 where the first bond portion 120 has a first bond profile. In some embodiments, the first bond portion 120 may include a first bonding material 124 configured to bond the two optical fibers 110, 112 together. The first bonding material 124 in the first bond portion 120 may have a cross-section 123 having a first bonding portion 121 that bonds to the first outer surface portion OS1 of the first optical fiber 110 and a second bonding portion 122 that bonds to the second outer surface portion OS2 of the second optical fiber 112. In some embodiments, the first bonding portion 121 and the second bonding portion 122 may only attach to the first and second optical fibers 110, 112, respectively, in the distal bondable area DBA. In some embodiments, the first bond portion 120 may be characterized as a strap bond profile or a strip bond profile.

[0104] In some embodiments, the first bond portion 120 may be structurally configured such that none of the first bonding material 124, or only a negligible amount of the first bonding material 124, is located at the first point P1 where the optical fibers 110, 112 meet or are closest together. In some embodiments, none of the bonding material, or only a negligible amount of the bounding material, may be located in the proximal bondable area PBA such that the proximal bondable area PBA is a void. In some embodiments, the first bond portion 120 may include a distal surface portion 127 and a proximal surface portion 129 opposite the distal surface portion 127. In some embodiments, none of the first bonding material 124, or only a negligible amount of the first bonding material 124, may be located in the bonding area BA within a distance D of the first point P1 , where the distance D may be at least 40%, at least 50%, at least 60%, or at least 70% of the height H (FIG. 2) of the bonding area BA. For example, none of the first bonding material 124 may be located proximal to the proximal surface portion 129 of the first bond portion 120.

[0105] Because the first bond portion 120 of FIG. 10 may contain less of the first bonding material 124 than the bond of FIG. 9, for a given bond material, the first bond portion 120 of FIG. 10 may be more easily stretched (and compressed) than the bond portion 12 of FIG. 9. In some embodiments, the first bond portion 120 may require lessstretching in a final cabled state than the bond portion 12 of FIG. 9 because of the hinged rotational capability of a strap hinge.

[0106] In some embodiments, the first bond portion 120 may include a second material 128 that is different from the first bonding material 124 in the first bond portion 120. For example, in some embodiments, the second material 128 may fill the bonding area BA between the first bonding material 124 and the first point P1 (e.g., between the optical fibers 110, 112 below the first bonding material 124 and to the first point P1 ). The second material 128 may be configured in a variety of ways. For example, second material 128 may be a bedding material structurally configured to provide a bed or foundation onto which the first bonding material 124 may be placed to prevent or inhibit the first bonding material 124 from contact with the first and second optical fibers 110, 112 past (i.e. , more proximal) from where the second material 128 is positioned.

[0107] In some embodiments, the second material 128 may be a non-bonding material or an uncured resin that will not bond to the optical fibers without curing. A variety of materials may be used as, or in, the second material 128 such as, but not limited to thixotropic gel, an acrylate, a silicone, a polyurethane, synthetic threads, thermoset resins, thermoplastic resins, etc.

[0108] FIG. 11 is an example of a second bond portion 130 having a second bonding profile. In some embodiments, the second bond portion 130 may provide a bonding length on the optical fibers 110, 112 (i.e., along the outer surfaces OS1 and OS2) similarto the bond profile of FIG. 9, but may include a reduced amount of bonding material 134 toward the midline ML In some embodiments, the reduced bonding material 134 may result in less of the bond being stretched, which may reduce the fiber surface area experiencing microbending stresses.

[0109] In some embodiments, the second bond portion 130 of FIG. 11 may reduce the amount of bonding material 134 when compared to the bond of FIG. 9 by eliminating some of the bonding material that is not attached to either of the optical fibers 110, 112. For example, the second bond portion 130 may include bonding material 134 attached to the optical fiber 110 along the outer surface OS1 of the first optical fiber 110between the first point P1 and the second point P2 and along the outer surface OS2 of the second optical fiber 112 between the first point P1 and the third point P3, but no bonding material along at least a portion of the midline ML between the first and second optical fibers 110, 112. For example, in some embodiments, the second bond portion 130 may have bonding material 134 fully filled in the bonding area BA between first and second optical fibers 110, 112 only a distance D2 of the first point P1 , where the distance D2 may be at least 60%, at least 50%, at least 40%, or at least 30% of the height H of the bonding area BA. For example, in some embodiments, the bonding material 134 may fully fill the proximal bondable area PBA or may fully fill only a portion of the proximal bondable area PBA.

[0110] In some embodiments, beyond the distance D2, the bonding material 134 may be positioned only along the outer surfaces OS1 , OS2 up to the tangent line TL. For example, the second bond portion 130 may be bifurcated or “V” shaped such the bonding material 134 extends fully between the optical fibers 110, 112 only in the bonding area BA from the first point P1 up to a bottom of the “V” at a point 133. In some embodiments, the second bond portion 130 may be bifurcated along the distal bondable area DBA or a portion of the distal bondable area DBA. Thus, the second bond portion 130 may have a first bonding portion 131 that bonds to the first outer surface portion OS1 of the first optical fiber 110 and a second bonding portion 132 that bonds to the second outer surface portion OS2 of the second optical fiber 112. In some embodiments, the first bonding portion 131 and the second bonding portion 132 may extend to the second point P2 and the third point P3. In other embodiments, the first bonding portion 131 and the second bonding portion 132 may not extend entirely to the may not extend to the second point P2 and the third point P3. For example, at least one of the first bonding portion 131 or the second bonding portion 132 may extend from the bottom of the “V” at a point 133 less than 50%, less than 60%, less than 70% or less than 80% the distance from point 133 to the first and second points P2, P3.

[0111] The second bond portion 130 may be figured to reduce the amount of bonding material that is stretched (or compressed) when the optical fibers 110, 112 aremoved (for example, rotated) relative to each other, therefore making such movement subject the optical fibers 110, 112 to less stress.

[0112] In some embodiments, beyond the distance D2, the bonding material 134 may be positioned only along the outer surfaces OS1 , OS2 but not extend up to the tangent line TL. In other words, the length of the bifurcated bonding portions above or distal to the bottom of the “V” at the point 133 less than the length shown in FIG. 11 . For example, in some embodiments, the length of the bifurcated bonding portions may be varied to adjust the amount of area where the bifurcated bonding portions bond to the outer surfaces OS1 and OS2 of the optical fibers 110, 112. In this way, the overall strength of the bond may be configured as desired.

[0113] FIG. 12 illustrates an example of a third bond portion 140 having a third bond profile. In some embodiments, the third bond portion 140 may be a hybrid bond that is somewhat similar to the first bond portion 120 of FIG. 10. For example, the third bond portion 140 may have a cross-section that may attach to the first optical fiber 110 only along a first bonding portion 141 of the outer surface OS1 and may attach to the second optical fiber 112 only along a second bonding portion 142 of the outer surface OS2. In some embodiments, the third bond portion 140 may be characterized as having a strap bond profile or a strip bond profile.

[0114] In some embodiments, the third bond portion 140 may include a distal surface portion 147 and a proximal surface portion 149 opposite the distal surface portion 147. In some embodiments, the distal surface portion 147 and / or the proximal surface portion 149 may be profiled (e.g., having a concave portion) to reduce the amount of bonding material that resists stretching. As shown in FIG. 12, in some embodiments, the third bond portion 140 may be thinner in an intermediate portion 143 (e.g., a central portion) inward from the locations where the third bond portion 140 is bonded to the optical fibers 110, 112. For example, in some embodiments, the third bond portion 140 may have an intermediate portion 143 that is smaller in cross sectional area than a first bonding portion 141 that bonds to the first outer surface portion OS1 of the first optical fiber 110 and the second bonding portion 142 that bonds to the second outer surface portion OS2.In some embodiments, the cross-section of the third bond portion 140 may be smallest at the midline ML of the third bond portion 140. Because the third bond portion 140 of FIG. 12 may contain less bonding material than the first bonding portion 120 of FIG. 10, for a given bond material, the third bond portion 140 of FIG. 12 may be more easily stretched (and compressed) than the first bonding portion 120 of FIG. 10.

[0115] FIG. 13 illustrates an example of a fourth bond portion 150 having a fourth bond profile. In some embodiments, the fourth bond portion 150 may be a hybrid bond that is somewhat similar to the first bond portion 120 of FIG. 10, but may have a different cross-sectional profile. For example, in some embodiments, the fourth bond portion 150 may have an intermediate portion 153 (e.g., a central portion) that has a distal surface portion 157 and a proximal surface portion 159 opposite the distal surface portion 157. In some embodiments, the distal surface portion 157 and the proximal surface portion 159 may be planar and parallel to each other along a width W. In some embodiments, the cross section of the intermediate portion 153 along the width W may have a smaller cross- sectional area than a first bonding portion 154 that may be structurally configured to bond to the outer surface OS1 of the first optical fiber 110 and / or than a second bonding portion 155 that may be structurally configured to bond to the outer surface OS2 of the second optical fiber 112. In some embodiments, cross-sectional area of the intermediate portion 153 may be uniform for at least 40%, for at least 50%, or for least 60% of a distance between the first bonding portion and the second bonding portion (or a distance between the outer surfaces of the optical fibers that the first bonding portion and the second bonding portion bond to). Because the fourth bond portion 150 may contain less bonding material than the first bond portion 120 of FIG. 10, for a given bond material, the fourth bond portion 150 of FIG. 13 may be more easily stretched (and compressed) than the first bond portion 120 of FIG. 10.

[0116] In some embodiments, the smaller cross-sectional area of the intermediate portion 143 of the third bond portion 140 of FIG. 12 may result in a more precisely targeted bending point than the relatively larger cross-sectional area of the intermediate portion 153 of the fourth bond portion 150 because the intermediate portion143 is in an area of the bond that is least resistant to bending. Accordingly, in some embodiments, the intermediate portion 143 may be shifted away from the mid-line ML of the bondable area BA to promote bending of the third bond portion 140 at a specific location along a length of the third bond portion 140. For example, in some embodiments, it might be beneficial to have the third bond portion 140 bend closer to one of the optical fibers 110, 112.

[0117] In the third and fourth bond portions 140, 150, the bonding portions 141 , 142, 151 , 152 of the bond portions 140, 150 having larger cross-sectional areas than the intermediate portions 143, 153, respectively, may reduce the stress (force per square area) applied to the fibers for a given force.

[0118] FIG. 14 illustrates an example of an optical fiber ribbon 1000 in which twelve optical fibers 110, 112, 114 are bonded together with eleven first bond portions 120 of FIG. 10. In other examples, however, more or fewer fibers may be bonded together to form the optical fiber ribbon 1000. In some embodiments, some of which are shown below, any combination of bonding profiles may be used to bond the optical fibers together, such as, for example, but not limited to, the first bond portion 120, the second bond portion 130, the third bond portion 140, the fourth bond portion 150, the bond portions 12 of FIG. 9. The bond portions 120, 130, 140, 150, 12 and other bonds may be provided on the top portion, on the bottom portion, or a combination of both, of the optical fiber ribbon 1000.

[0119] FIGS. 15-16 illustrate the first bond portion 120 during rotation of two optical fibers 110, 112 relative to each other. FIG. 15 shows the optical fibers 110, 112 at a rest position with the first bond portion 120 in an upper position. Note the location of points C and D of the optical fibers 112, 110, respectively. As the optical fibers 110, 112 are rotated in the directions of arrows F, points C and D move toward each other and the first bond portion 120 moves downward between the optical fibers 110, 112 as shown in FIG. 16. In this example, as this rotation happens, the optical fibers 110, 112 move away from each other as the first bond portion 120 passes between them. Further rotation of the optical fibers 110, 112 may cause the first bond portion 120 to move to a locationbelow the optical fibers 110, 112 as shown in FIG. 17. At the position shown in FIG. 17, the first bond portion 120 is in tension at its lowest section and in compression at its upper section (the upper section being between points C and D). In this example, the optical fibers 110, 112 are rotated approximately 135 degrees relative to each other with minimal stretch of the bond portion in the final position.

[0120] The first bond portion 120 being moved through the rotation shown in FIGS. 15-17 applies much less stress to the optical fibers 110, 112 than would be applied to two fibers bonded with the bond portion shown in FIG. 9, that is if such rotation of the bond portion shown in FIG. 9 is even possible. This reduction of stress results from the reduction of bond material that must be stretched and / or compressed and the smaller contact area of the bond with the optical fibers.

[0121] FIGS. 18 and 19 illustrate example folding patterns of an optical fiber ribbon of the present disclosure that can be created to optimize the tightening of fibers into a small group, while minimizing inherent stress on the fibers. FIG. 19 illustrates an exemplary cable 2000 that has a jacket 2010 around aramid packing 2020 that surround the ribbon 100. In this example, an aramid central strength member 2030 may provide strength to the cable 2000 and may help in the formation of the bundle itself. Other examples may include a multi-layered jacket, multiple jackets, different or no packing, and / or fewer or more central strength members of aramid or different material.

[0122] FIGS. 20 and 21 illustrate the second bond portion 130 between the optical fibers 110, 112. In some embodiments, the second bond portion 130 may provide a large surface bonding area on the optical fibers 110, 112 and may act as a hinge between the optical fibers 110, 112, as shown by arrow A. While some material flexing may still be required, the amount of fiber surface area under stress may be greatly reduced because of the configuration of the profile of the second bond portion 130 that allows the V-shape profile to act as a hinge. In some embodiments, absence of bonding material in the area E results in less microbending stress on the optical fibers 110, 112 during fiber rotation than, for example, the bond portion 12 of FIG. 9.

[0123] In practical application, ribbons will sometimes form into an “S” or a “W” shape during the cabling process (often the path of least resistance), as opposed to a true coil. FIG. 22 illustrates an example optical fiber ribbon 2100 that combines both first bond portions 120 and second bond portions 130, where the preferred direction of the rotation of the second bond portion 130 is opposite that of the first bond portion 120. FIG. 23 illustrates a magnified portion of FIG. 22 that more clearly shows the use of both the first bond portions 120 and the second bond portions 130.

[0124] FIG. 24 illustrates an example of an optical fiber ribbon 2300 that uses a combination of bonds on the top and bottom of optical fiber ribbon. In some embodiments, the cross-sectional profiles of the first bond portions 120 may be different shapes to facilitate folding or coiling. For example, in some embodiments, the first bond portions 120 may be other than flat on the top portion or the bottom portion of the optical fiber ribbon 2300. By selecting the use of a particular one of the exemplary bond portions 120, 130, 140, 150, 12, or other bond portions in each of the bonding locations on the optical fiber ribbon 2300 and / or selected placement of the bond portions on the top portion or the bottom portion of the optical fiber ribbon, a ribbon designer may create an optical fiber ribbon that more easily conforms to a desired shape inside a cable.

[0125] FIG. 25 illustrates an example optical fiber ribbon 2500 having a plurality of optical fibers 11 a-111 bonded together by intermittently spaced-apart bond portions 12. In some embodiments, each of the intermittently spaced-apart bond portions 12 may have the same bond profile (e.g., all may be first bond portions 120 or all may be second bond portions 130, etc.). In other embodiments, however, the profile of the bond portions may vary along the length of two adjacent fibers and / or may between pairs of intermittently bonded fibers (e.g., the bond profile used between the optical fibers 11 a and 11 b may be different than the bond profile used between the optical fibers 11 b and 11c).

[0126] In some embodiments, as illustrated in FIG. 25, the profile of the bond portion 12 may vary between two adjacent fibers. In FIG. 25, optical fiber 11 a is intermittently bonded to optical fiber 11 b by the plurality of intermittently spaced-apart bond portions 12. A first of the intermittently spaced-apart bond portions 12 may have theprofile of the first bond portion 120 of FIG. 10 and a second of the intermittently spacedapart bond portions 12 may have the profile of the second bond portion 130 of FIG. 11. Which bond profile (e.g., bond portions 120, 130, 140, 150, 12) is used at each bonding location may vary in different embodiments as desired by the ribbon designer.

[0127] FIG. 26 illustrates an example optical fiber ribbon 2600 having a plurality of optical fibers 11 a-111 bonded together by intermittently spaced-apart bond portions 12. In some embodiments, each of the intermittently spaced-apart bond portions 12 may have a single bond profile. In other words, the bond profile does not vary along the length bond portion. In other embodiments, however, the profile may vary within each bond portion. For example, in some embodiments, as illustrated in FIG. 26, the profile one or more of the bond portions 12 may vary along the length of the bond portion. In FIG. 26, the optical fiber 11 a is intermittently bonded to optical fiber 11 b by the plurality of intermittently spaced-apart bond portions 12. A first of the intermittently spaced-apart bond portions 12 may have the profile of the first bond portion 120 of FIG. 9. A second of the intermittently spaced-apart bond portions 12 may a first portion of the bond portion have the profile of the first bond portion 120 and a second portion of the bond portion have the profile of the second bond portion 130 of FIG. 10. Which bond portions have a consistent profile and which bond portions have a profile that may vary along the length of the bond portion may vary in different embodiments as desired by the ribbon designer.

[0128] Although the illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope or spirit of the invention.

[0129] Various changes to the foregoing described and shown structures will now be evident to those skilled in the art. Accordingly, the particularly disclosed scope of the invention is set forth in the following claims.

Claims

WHAT IS CLAIMED IS1. An optical fiber ribbon with bond portions structurally configured to provide enhanced flexibility to the ribbon and reduced stress between bonded optical fibers, comprising: a first optical fiber; a second optical fiber bonded to the first optical fiber along a longitudinal direction of the first optical fiber by a bond portion; wherein the bond portion is a first bond portion of a plurality of bond portions, and the second fiber is intermittently bonded to the first fiber by the plurality of bond portions; wherein a first location on the first optical fiber is a location at which the first optical fiber is closest to the second optical fiber; wherein a first area is defined as a first cross-sectional area between the first optical fiber and the second optical fiber, and between the first location on the first optical fiber and a first line tangent to outer surfaces of both the first optical fiber and the second optical fiber; wherein the first area includes a proximal area adjacent the first location and a distal area adjacent the first line; wherein the first cross-sectional area is in a cross-sectional plane perpendicular to the longitudinal direction of the first optical fiber; wherein the bond portion is located in the first area; wherein the bond portion is not located along a transverse line within one of the proximal area or the distal area, wherein the transverse line extends perpendicular from the first line through the first location; and wherein the bond portion provides reduced stress between the first optical fiber and the second optical fiber while permitting the first optical fiber to move relative to the second optical fiber to facilitate bending of the ribbon in a transverse direction.

2. The optical fiber ribbon of claim 1 , wherein the bond portion includes a distal surface portion and a proximal surface portion opposite the distal surface portion, wherein the proximal surface portion is spaced apart from the first point by a portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber.

3. The optical fiber ribbon of claim 2, wherein the bond portion includes a first bonding portion configured to bond to the first optical fiber, a second bonding portion configured to bond to the second optical fiber, and an intermediate portion between the first bonding portion and the second bonding portion, wherein the intermediate portion has a cross-sectional area that is smaller than a cross-sectional area of at least one of the first bonding portion and the second bonding portion.

4. The optical fiber ribbon of claim 3, wherein at least one of the distal surface portion or the proximal surface portion includes a concave portion in the intermediate portion.

5. The optical fiber ribbon of claim 3 or 4, wherein the cross-sectional area of the intermediate portion is uniform for at least 50% of a distance between the first bonding portion and the second bonding portion.

6. The optical fiber ribbon of any of claims 2-5, wherein the portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber includes a non-bonding material configured to provide a bedding for the bond portion.

7. The optical fiber ribbon of claim 1 , wherein the bond portion has a V-shaped cross- sectional shape.

8. The optical fiber ribbon of claim 7, wherein the first area has a height measured from the first point to the first line, and wherein the bond portion fully fills the first area below a distance that is in the range of 30% to 60% of the height and the bond is bifurcated beyond the distance.

9. The optical fiber ribbon of any of claims 1-8, wherein the bond portion extends to the first line.

10. The optical fiber ribbon of any of claims 1 -8, wherein the bond portion does not extend to the first line.11 . The optical fiber ribbon of any of claims 1 -10, wherein the bond is a first bond; wherein the optical fiber ribbon further comprises a second bond portion having a different cross-sectional shape than a cross-sectional shape of the first bond portion; wherein the second bond portion is a second bond portion of the plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber.

12. An optical fiber ribbon with bond portions structurally configured to provide enhanced flexibility to the ribbon and reduced stress between bonded optical fibers, comprising: a first optical fiber; a second optical fiber bonded to the first optical fiber along a longitudinal direction of the first optical fiber by a bond portion; wherein a first location on the first optical fiber is a location at which the first optical fiber is closest to the second optical fiber; wherein a first area is defined as a first cross-sectional area between the first optical fiber and the second optical fiber, and between the first location on thefirst optical fiber and a first line tangent to outer surfaces of both the first optical fiber and the second optical fiber; wherein the first area includes a proximal area adjacent the first location and a distal area adjacent the first line; wherein the first fiber comprises a glass core inside a first protective coating system; wherein the second fiber comprises a second glass core inside a second protective coating system; wherein the first line is tangent to an outer surface of the first protective coating system and an outer surface of the second protective coating system; wherein the bond portion is located in the first area; wherein the bond portion is not located along a transverse line within one of the proximal area or the distal area, and wherein the transverse line extends perpendicular from the first line through the first location; and wherein the bond portion provides reduced stress between the first optical fiber and the second optical fiber while permitting the first optical fiber to move relative to the second optical fiber to facilitate bending of the ribbon in a transverse direction.

13. The optical fiber ribbon of claim 12, wherein the bond portion includes a distal surface portion and a proximal surface portion opposite the distal surface portion, wherein the proximal surface portion is spaced apart from the first point by a portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber.

14. The optical fiber ribbon of claim 13, wherein the bond portion includes a first bonding portion configured to bond to the first optical fiber, a second bonding portion configured to bond to the second optical fiber, and an intermediate portion between the first bonding portion and the second bonding portion.

15. The optical fiber ribbon of claim 14, wherein the intermediate portion has a cross- sectional area that is smaller than a cross-sectional area of at least one of the first bonding portion and the second bonding portion.

16. The optical fiber ribbon of claim 15, wherein at least one of the distal surface portion or the proximal surface portion includes a concave portion in the intermediate portion.

17. The optical fiber ribbon of claim 15 or 16, wherein the cross-sectional area of the intermediate portion is uniform for at least 50% of a distance between the first bonding portion and the second bonding portion.

18. The optical fiber ribbon of any of claims 13-17, wherein the portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber includes a non-bonding material configured to provide a bedding for the bond portion.

19. The optical fiber ribbon of claim 12, wherein the bond portion has a V shaped cross-sectional shape.

20. The optical fiber ribbon of claim 19, wherein the first area has a height measured from the first point to the first line, and wherein the bond portion fully fills the first area below a distance that is in the range of 30% to 60% of the height and the bond is bifurcated beyond the distance.21 . The optical fiber ribbon of any of claims 12-20, wherein the bond portion is a first bond portion of a plurality of bond portions, and the second optical fiber is intermittently bonded to the first fiber by the plurality of bond portions.

22. The ribbon of any of claims 12-21 , wherein the bond portion extends to the first line.

23. The ribbon of any of claims 12-22, wherein the first location is a point where the first protective coating system contacts the second protective coating system.

24. The ribbon of any of claims 12-23, wherein the bond portion is a first bond portion; wherein the optical fiber ribbon further comprises a second bond portion having a different cross-sectional shape than a cross-sectional shape of the first bond portion; wherein the first bond portion is a first bond portion of a plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber; and wherein the second bond portion is a second bond portion of the plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber.

25. An optical fiber ribbon with bond portions structurally configured to provide enhanced flexibility to the ribbon and reduced stress between bonded optical fibers, comprising: a first optical fiber bonded to a second optical fiber along a longitudinal direction of the first optical fiber by a bond portion; wherein a first location on the first optical fiber is a location at which the first optical fiber is closest to the second optical fiber; wherein a first area is defined as a first cross-sectional area between the first optical fiber and the second optical fiber, and between the first location on the first optical fiber and a first line tangent to outer surfaces of both the first optical fiber and the second optical fiber;wherein the bond portion is located in the first area but does not fully fill the first area; and wherein the bond portion provides reduced stress between the first optical fiber and the second optical fiber while permitting the first optical fiber to move relative to the second optical fiber to facilitate bending of the ribbon in a transverse direction.

26. The optical fiber ribbon of claim 25, wherein the first optical fiber comprises a glass core inside a first protective coating system, the second optical fiber comprises a second glass core inside a second protective coating system, and the first line is tangent to an outer surface of the first protective coating system and an outer surface of the second protective coating system.

27. The optical fiber ribbon of claim 25 or 26, wherein the bond portion includes a distal surface portion and a proximal surface portion opposite the distal surface portion, wherein the proximal surface portion is spaced apart from the first point by a portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber.

28. The optical fiber ribbon of claim 27, wherein the bond portion includes a first bonding portion configured to bond to the first optical fiber, a second bonding portion configured to bond to the second optical fiber, and an intermediate portion between the first bonding portion and the second bonding portion, and wherein intermediate portion has a cross-sectional area that is smaller than a cross- sectional area of at least one of the first bonding portion and the second bonding portion.

29. The optical fiber ribbon of claim 28, wherein at least one of the distal surface portion or the proximal surface portion includes a concave portion in the intermediate portion.

30. The optical fiber ribbon of claim 28 or 29, wherein the cross sectional area of the intermediate portion is uniform for at least 50% of a distance between the first bonding portion and the second bonding portion.31 . The optical fiber ribbon of any of claims 27-30, wherein the portion of the first area that is devoid of a bond between the first optical fiber and the second optical fiber includes a non-bonding material configured to function as a bedding material for the bond portion.

32. The optical fiber ribbon of claim 25, wherein the bond portion has a V shaped cross-sectional shape.

33. The optical fiber ribbon of claim 32, wherein the first area has a height measured from the first point to the first line, and wherein the bond portion fully fills the first area below a distance that is in the range of 30% to 60% of the height and the bond is bifurcated beyond the distance.

34. The optical fiber ribbon of claims 25-33, wherein the bond portion is a first bond portion of a plurality of bond portions, and the second optical fiber is intermittently bonded to the first optical fiber by the plurality of bond portions.

35. The optical fiber ribbon of any of claims 25-34, wherein the bond portion extends to the first line.

6. The optical fiber ribbon of any of claims 25-35, wherein the bond portion is a first bond portion; wherein the optical fiber ribbon further comprises a second bond portion having a different cross-sectional shape than a cross-sectional shape of the first bond portion; wherein the first bond portion is a first bond portion of plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber; and wherein the second bond portion is second bond portion of the plurality of bond portions that intermittently bond the first optical fiber to the second optical fiber.

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