Abstract: An optical fiber unit includes: an optical fiber ribbon in which a plurality of optical fibers are arranged in parallel and connected to each other; a colored bundle tape longitudinally wrapped around an optical fiber ribbon bundle in which a plurality of the optical fiber ribbons are stranded together; and a colored bundle yarn spirally wound around the optical fiber ribbon bundle and the bundle tape.

Abstract: An optical fiber cable includes: optical fiber units each having optical fibers; a wrapping tube that wraps around the optical fiber units; a filling disposed inside the wrapping tube; and a sheath that covers the wrapping tube. The optical fiber units includes outer units that are disposed at an outermost layer of the optical fiber units. The outer units are twisted in an SZ shape around a cable central axis of the optical fiber cable. The filling is sandwiched between one of the outer units and the wrapping tube in a cross-sectional view.

Abstract: The present description provides multimode optical fibers with reduced cladding thickness. The optical fibers include a reduced-diameter glass fiber and/or reduced-thickness coatings. The overall diameter of the optical fibers is less than 210 ?m and examples with diameters less than 160 ?m are presented. Puncture resistant secondary coatings enable thinning of the secondary coating without compromising protection of the glass fiber. The optical fibers are suitable for data center applications and features high modal bandwidth, low attenuation, low microbending sensitivity, and puncture resistance in a compact form factor.

Abstract: This application relates to a fibre optic cable structure suitable for use as a sensing fibre optic for distributed acoustic sensing and having an improved sensitivity to transverse pressure waves. The application describes a fibre optic cable (300) having a longitudinal cable axis and comprising at least one optical fibre (301). The cable also comprises a compliant core material (303) mechanically coupled to the optical fibre(s), possible via a buffer (302) such that a longitudinal force acting on the compliant core material induces a longitudinal strain in the optical fibre(s). At least one deformable strain transformer (304) is coupled to the compliant core material and configured such that a force acting on the strain transformer in a direction transverse to the cable axis results in a deformation of the strain transformer thereby applying a longitudinal force to the compliant core material.

Abstract: A high bandwidth radiation-resistant multimode optical fiber includes a core and a cladding layer surrounding the core. The core is a fluorine-doped quartz glass layer with a graded refractive index distribution and a distribution power exponent ? of 1.7-2.2. The core has R1 of 15-35 ?m and ?1%min of ?0.8% to ?1.2%. The cladding layer has an inner cladding layer having R2 of 15-38 ?m and ?2% of ?0.8% to ?1.2% and/or a depressed inner cladding layer having R3 of 15-55 ?m and ?3 of ?1.0% to ?1.4%, an intermediate cladding layer having R4 of 15.5-58 ?m and ?4 of ?0.7% to ?0.2% a depressed cladding layer hasving R5 of 16-60 ?m and ?5 of ?0.8% to ?1.2%, and an outer cladding layer sequentially formed from inside to outside. The outer cladding layer is a pure silica glass layer.

Abstract: The present disclosure is directed toward a cuvette for holding a test sample during optical interrogation with a light signal. The transmissivity of the cuvette is increased by a geometric anti-reflection layer disposed on at least one surface of the cuvette, where the geometric anti-reflection layer includes a plurality of geometric features that collectively reduce the reflectivity of the interface between the surface and another medium. As a result, more of the interrogation signal passes through the interface. In some embodiments, every surface through which the interrogation signal passes includes a geometric anti-reflection layer. Due to the increased transmissivity of the cuvette, light detected after passing through it can have an improved signal-to-noise ratio and/or the light signal used to interrogate the sample can have lower intensity. In addition, the reduction of the reflectivity of each surface enables the use of low-cost, high-refractive-index materials, such as conventional silicon.

Abstract: A DPTSS fiber optic cable includes an optical fiber sheathing cylindrical metal tube accommodating a pressure sensor optical fiber and having a plurality of through holes formed therein; and pressure blocking sections formed at intervals in the axial direction of the cable.

Abstract: A disclosed cable includes a roll of flexible substrate. The substrate has opposing first and second surfaces and the roll is structured around an axis. A plurality of electrically conductive wires are attached to the first surface of the substrate, and the roll of flexible substrate and attached plurality of wires have alternating layers of wires and substrate.

Abstract: An optical communication cable and related method is provided. The cable includes a cable body and a plurality of optical transmission elements surrounded by the cable body. The cable includes a reinforcement layer surrounding the plurality of optical transmission elements and located between the cable body and the plurality of optical transmission elements. The reinforcement layer includes an outer surface and a channel defined in the outer surface that extends in the longitudinal direction along at least a portion of the length of the cable. The cable includes an elongate strength element extending in the longitudinal direction within the channel.

Abstract: An optical communication cable is provided. The optical communication cable includes an outer cable layer and a plurality of optical fiber bundles surrounded by the outer cable layer. Each optical fiber bundle includes a bundle jacket surrounding a plurality of optical fiber subunits located within the bundle passage. The plurality of optical subunits are wrapped around each other within the bundle passage forming a wrapped pattern. Each optical fiber subunit includes a subunit jacket surrounding a elongate optical fiber located within the subunit passage. The cable jacket, bundle jacket and subunit jacket may be fire resistant, and strength strands of differing lengths may be located in the bundles and the subunits.

Abstract: An optical fiber cable comprising 200 micrometer (?m) optical fibers (fibers with an outer diameter of approximately 200 ?m) that are located within buffer tubes. This permits fiber packing densities of 3.8 fibers/mm2 or higher. The buffer tubes have wall thicknesses (tbuffer) between approximately 7.5 percent (7.5%) and approximately 30% of the buffer tube's outer diameter (ODbuffer), and a Young's modulus that is between approximately 750 mega-pascals (MPa) and 2,200 MPa, thereby providing the necessary structural integrity to resist kinking yet maintain flexibility.

Abstract: A fiber optic ribbon cable includes a stack of fiber optic ribbons, strength members surrounding the stack, and a jacket defining an exterior of the cable. The jacket forms a cavity through which the stack and the strength members extend. The stack has a bend preference, but the strength members are positioned around the stack or are flexible in bending such that the strength members do not have a bend preference. Furthermore, the jacket is structured such that the jacket does not have a bend preference. The cavity is sized relative to the stack in order to allow the stack to bend and twist within the cavity with respect to the jacket as the cable bends, facilitating movement of the optical fibers of the fiber optic ribbons to low-stress positions within the cavity and decoupling the bend preference of the stack from transfer to the jacket.

Abstract: In an optical fiber cable that includes an optical fiber core for measuring pressure and a multilayer armor cable for measuring temperature, an annular clearance space having a desired thickness is formed between the optical fiber core and the multilayer armor cable and fixing members for fixing the optical fiber core and the multilayer armor cable are provided at predetermined intervals in the axial direction of the optical fiber cable.

Abstract: An assembly for guiding and protecting optical fiber cables or wave guides, which comprises a first number of first guide tubes and a second number of second guide tubes where each of the first and second guide tubes are adapted to receive an optical fiber cable along its complete length. The assembly further comprises an elongated first tubular shell, and an elongated second tubular shell where the first number of first guide tubes is supported within and in parallel relationship with the first tubular shell, and the second number of second guide tubes is supported within and in parallel relationship with the second tubular shell. The assembly further comprises a first connecting strip which interconnects the first and second tubular shells, which defines a separation between the first and second tubular shells, and which positions the first number of first guide tubes and the second number of second guide tubes in parallel.

Abstract: A high performance communications cable includes core support-separators which define clearance channels to maintain spacing between transmission media or transmission media pairs. The core support-separator can be either interior to a cable jacket or be employed singularly without the benefit of a jacket and extends along the longitudinal length of the communications cable. Alternatively, with no jacket for cable completion, a thin layer of material along the exterior of the support-separator acts as a type of skin for mechanical protection. The core support-separator has a central region that includes flap-tops along the radial edge that are available for partial or complete sealing of the clearance channels during manufacturing operations. The central region may also include a hollow center portion. Each of the defined clearance channels allow for disposal therein of metal conductors and/or optical fibers.

Abstract: A production method for a headline sonar cable (20, 120) that exhibits a high breaking-strength and lighter weight than a conventional steel headline sonar cable. Producing the headline sonar cable (20, 120) is characterized by the steps of: a. providing an elongatable internally-located conductive structure (34, 134) that is adapted for data signal transmission; and b. braiding a strength-member jacket layer (52) of polymeric material around the structure (34, 134) while ensuring that the structure (34, 134) is slack when surrounded by the jacket layer (52). The structure (34, 134) of the cable (20, 120) retains conductivity upon stretching of the jacket layer (52) surrounding the structure (34, 134) that lengthens the cable (20, 120). For one embodiment of the method a conductor (20) wrapped around a rod (24) and enclosed within a sheath layer (32) forms the structure (34, 134).

Abstract: A distributed acoustic sensor, comprises a housing having a longitudinal bore therethrough, an optical fiber supported in the bore; and an inertial member supported within the bore, wherein the fiber is mechanically coupled to the inertial member. The inertial member may include a weight and may provides isotropic stiffness such that it deforms more readily in a first direction normal to the bore than it does in a second direction that is normal to both the bore and the first direction. The sensor may include a plurality of axially-spaced centralizers in the bore, and at least one of the inertial member and the centralizers may comprise swellable material.

Abstract: An optical fiber cable including, in a radial direction outward, a central strength member, a first layer of loose buffer tubes stranded around the central strength member, at least one of the loose buffer tubes of the first layer containing at least one light waveguide, an intermediate layer, a second layer of loose buffer tubes stranded around the intermediate layer, at least one of the loose buffer tubes of the second layer containing at least one light waveguide, and a jacket surrounding the second layer of loose buffer tubes, wherein the intermediate layer is formed of a material having a high coefficient of friction.

Abstract: A breakout cable includes a polymer jacket and a plurality of micromodules enclosed within the jacket. Each micromodule has a plurality of bend resistant optical fibers and a polymer sheath comprising PVC surrounding the bend resistant optical fibers. Each of the plurality of bend resistant optical fibers is a multimode optical fiber including a glass cladding region surrounding and directly adjacent to a glass core region. The core region is a graded-index glass core region, where the refractive index of the core region has a profile having a parabolic or substantially curved shape. The cladding includes a first annular portion having a lesser refractive index relative to a second annular portion of the cladding. The first annular portion is interior to the second annular portion. The cladding is surrounded by a low modulus primary coating and a high modulus secondary coating.

Abstract: Multi-fiber, fiber optic cable assemblies and related fiber optic components, cables, and methods providing constrained optical fibers within an optical fiber sub-unit are disclosed. The optical fiber sub-unit(s) comprises optical fibers disposed adjacent a sub-unit strength member(s) within a sub-unit jacket. Movement of optical fibers within a sub-unit jacket can be constrained. In this manner, the optical fibers in an optical fiber sub-unit can be held together within the optical fiber sub-unit as a unit. As a non-limiting example, the optical fiber sub-unit(s) may be exposed and constrained in a furcation assembly as opposed to the optical fibers, thereby reducing complexity in fiber optic cable assembly preparations. Constraining the optical fibers may also allow optical skew, reduction of entanglement between the optical fibers and the cable strength members to reduce or avoid optical attenuation, and/or allow the optical fibers to act as anti-buckling components within the fiber optic cable.

Abstract: A fiber optic cable includes a cable jacket and a core. The cable jacket is tubular, having exterior and interior surfaces, and is formed mostly from a first polymeric material. The jacket includes access features formed from a second polymeric material at least partially embedded in the first polymeric material and extending lengthwise along the jacket. Two of the access features are spaced apart from one another with a section of the jacket formed from the first polymeric material extending laterally therebetween, such that the section may be peeled apart from the rest of the cable lengthwise along the jacket by separation of the jacket about the access features. The core has an outermost surface and includes optical fibers and a strength member. The outermost surface of the core is at least partially bonded to the interior surface of the jacket, which enhances coupling between the jacket and core.

Abstract: An example fiber optic cable includes an outer jacket having an elongated transverse cross-sectional profile defining a major axis and a minor axis. The transverse cross-sectional profile has a maximum width that extends along the major axis and a maximum thickness that extends along the minor axis. The maximum width of the transverse cross-sectional profile is longer than the maximum thickness of the transverse cross-sectional profile. The outer jacket also defines first and second separate passages that extend through the outer jacket along a lengthwise axis of the outer jacket. The second passage has a transverse cross-sectional profile that is elongated in an orientation extending along the major axis of the outer jacket. The fiber optic cable also includes a plurality of optical fibers positioned within the first passage a tensile strength member positioned within the second passage.

Abstract: An arrangement provides for an optical fiber cable having a plurality of fiber optic elements including a glass portion and a UV optical coating portion. A plurality of buffer tubes each contain one or more of the plurality of optical fibers made of a fire retardant polymer. A jacket surrounds the buffer tubes also made of a fire retardant polymer. The fire retardant polymers for the plurality of buffer tubes and for the jacket are selected from PVDF (PolyVinyliDene Fluoride) or FRPVC (Fire Resistance Poly Vinyl Chloride). The ratio of total polymer to UV optical coating of the fiber optic elements, by area, is substantially in the range of 5:1 to 9:1.

Abstract: An optical cable includes a buffer tube housing at least one optical fiber, a sheath surrounding such buffer tube and at least one longitudinal strength member embedded in the sheath, in which at least one separation element is provided between a portion of the outer surface of the buffer tube and the inner surface of the sheath, laying in an axial plane not containing the at least one strength member.

Abstract: A fiber optic cable can comprise a jacket enclosing an internal space. A member extending lengthwise within the space can provide two or more compartments. Each compartment can house a respective bundle of optical fibers that are color coded for distinguishing the fibers of an individual bundle from one another. Different compartments can house different number of optical fibers. The compartments can comprise indicia for distinguishing the compartments and/or the bundles from one another. The member can be formed by extrusion and can have removable or detachable fins. With the extruded member in a relaxed state, the compartments can be closed. A series of dies can insert the bundles of optical fibers in the compartments. The dies can manipulate the member to open the compartments for bundle insertion. Once the bundles are inserted in the respective compartments, the dies can release the member so the compartments close on the bundles.

Abstract: A rack cabling system including a rack having mounted thereon a first hardware component and a patch panel housing mounted on the rack adjacent the first hardware component. The patch panel housing populates no more than a three rack unit (RU space), the patch panel housing including a first end having cable pathway openings and a second end having connector elements mounted therein. The patch panel may have a first cable pathway opening located adjacent the first side of the housing and defining a primary position and a first connector element mounted on the second end and the first connector element having a first position corresponding to the primary position of the first cable pathway opening. Cable harnesses are routed with less than three bends of the cables between the first hardware component and the patch panel housing, so that the first cable harness is terminated at the first connector element in the first position.

Abstract: Robust fiber optic cables and assemblies having low attenuation multimode optical fibers. The cables have low attenuation in tensile and mandrel wrap tests, and can have thermoplastic urethane jackets coextruded over tensile strength members that allow the cables to be pulled by the jackets. The cables have relatively small cross-sections yet have sufficient robustness to be deployed in extreme environments such as cellular tower applications.

Abstract: Micromodule subunit cables are constructed to allow for ease of identification between optical fibers in differing groups of optical fibers. In one cable, a first group of fibers is located within a first subunit while a second group of fibers is located within a second subunit, both subunits being enclosed in a cable jacket.

Abstract: An earth cable adapted for being laid underground includes at least one optical fiber, a thermally conducting polymeric layer surrounding the at least one optical fiber, and copper conductors arranged in a radially-external position with respect to the thermally conducting polymeric layer.

Abstract: A cable includes a channel with an aspect ratio that houses optical fibers therein. The cable includes first and second stranded conductors on opposing sides of the channel. The channel is arranged with respect to the stranded conductors so that the fibers assume low strain positions in the channel when the cable is bent.

Abstract: Micromodule subunit cables are constructed to allow for ease of identification between optical fibers in differing groups of optical fibers. In one cable, a first group of fibers is located within a buffer tube core while a second group of fibers is located within the cable jacket, but outside of the core. The fibers in the first and second groups can accordingly use the same color coding sequence without requiring additional indicia such as stripes or binding.

Abstract: A fiber optic cable includes a jacket, strength members, armor, and a tear feature. The jacket is formed from a first polymeric material and defines an exterior of the cable. The jacket further forms an interior cavity configured to support an optical fiber. The strength members are each surrounded by the jacket, with the cavity separating the strength members from one another. The armor extends above the cavity and at least partially above the strength members, and has greater tensile strength than the first polymeric material. The tear feature is located beneath the armor and is formed from a second polymeric material co-extrudable with the first polymeric material. The tear feature forms a discontinuity of material within the jacket. At least one of the second polymeric material and the interface between the first and second polymeric materials yields at a lesser tearing force than the first polymeric material.

Abstract: A connection system includes an optical connector assembly; and an optical plug. The connector assembly includes a stack of gel-groove assemblies and a spring assembly mounted within a housing. Each of the gel-groove assemblies includes a first gel block at a first axial end, a second gel block at a second axial end, and a fiber mating region between the first and second gel blocks. The optical plug including sub-modules over-molded over arrays (e.g., ribbons) of the optical fibers. Each sub-module defines notches for receiving latches of the spring assembly when the optical plug is coupled to the first axial end of the optical adapter. Bare optical fibers extend from the plug, pass through the first axial gel block, and enter the fiber mating region when the plug is coupled to the adapter.

Abstract: An optical fiber assembly includes a core. The core includes a central portion and a plurality of fins that extends radially outward from the central portion. The central portion defines a central passage. The central portion and the plurality of fins cooperatively define a plurality of grooves that is helically oriented along a length of the core. A plurality of optical fibers is disposed in the plurality of grooves. A strength member is disposed in the central passage of the core. An outer covering surrounds the core. The outer covering is air permeable.

Abstract: Micromodule breakout cables are constructed to pass selected burn tests while maintaining a desired degree of accessibility and durability. The micromodule cables can be incorporated in data centers and are robust enough to serve as furcation legs while allowing hand accessibility. The cables can incorporate optical fibers with low delta attenuation and can have low skew.

Abstract: A fiber optic cable with first and second cavities accommodating separate groups of fibers. Arranging the optical fibers in separate cavities allows the fibers to be distinguished from one another without requiring secondary marking indicia such as stripes on the fibers. The cable jacket can be extruded such that the cavities are formed integrally in the jacket during extrusion.

Abstract: An optical-electrical hybrid transmission cable (100), comprises an insulative layer (2); a shielding layer located on an inner side of the insulative layer; an optical cable (5) disposed in the shielding layer and comprising two optical fibers (51) and an insulative sheath (52) enclosing the two optical fibers; a pair of signal wires (6) twisted together and disposed in the shielding layer; and a pair of power wires disposed in the shielding layer. And the optical cable, the pair of signal wires and the pair of power wires are arranged along a circumferential direction.

Abstract: A fiber optic cable includes a plurality of optical fiber subunits, each of the subunits including four fiber optic elements and an enclosing jacket. A plurality of optical fiber subunit assemblies are also included, each of which includes a plurality of the optical fiber subunits and an enclosing micro-sheath. The subunits are stranded around one another. A sheath encloses the plurality of optical fiber subunit assemblies.

Abstract: Robust fiber optic cables and assemblies having low attenuation multimode optical fibers. The cables have low attenuation in tensile and mandrel wrap tests, and can have thermoplastic urethane jackets coextruded over tensile strength members that allow the cables to be pulled by the jackets. The cables have relatively small cross-sections yet have sufficient robustness to be deployed in extreme environments such as cellular tower applications.

Abstract: Described are track-resistant all dielectric self-supporting (TR-ADSS) cables with improved cable jackets. A typical TR-ADSS optical fiber cable comprises an optical fiber sub-assembly, and a cable jacket system. The cable jacket system comprises an inner jacket, an aramid strength layer and an outer jacket. The improvement in the cable jacket system results from the addition of a friction layer between the aramid strength layer and the outer jacket. The friction layer prevents unwanted slippage of the outer jacket with respect to the inner portions of the cable.

Abstract: An optical fiber cable includes an unbuffered optical fiber, a tensile reinforcement member surrounding the unbuffered optical fiber, and a jacket surrounding the tensile reinforcement member. The jacket is suitable for outside plant environment. A water blocking material is placed between the unbuffered fiber and the jacket. The unbuffered optical fiber comprises an ultra bend-insensitive fiber that meets the requirements of ITU-T G.657.B3 and exhibits an additional loss of less than approximately 0.2 dB/turn when the fiber is wrapped around a 5 mm bend radius mandrel. The optical fiber cable also exhibits an additional loss of less than approximately 0.4 dB/km at 1550 nm when the cable is subjected to ?20° C. outside plant environment.

Abstract: The present invention provides optical fiber communication cable assemblies useful for separating and conveying individual fibers from a multiple optical fiber cable to connectors in a protective manner. The optical fiber cable assembly is suitable for outdoor use and includes a (i) cable with multiple optical fibers; (ii) a furcation unit attached to the cable for directing individual optical fibers from the cable to furcation legs; and (iii) multiple furcation legs receiving at least one of the optical fibers. The furcation legs include (i) a buffer tube surrounding the optical fiber; (ii) strength members surrounding the buffer tube; and (iii) a jacket surrounding the strength members. The furcation legs typically exhibit a tensile rating of at least about 50 pounds (lbf), more typically 100 pounds (lbf) or more. Moreover, the furcation legs typically exhibit total shrinkage of less than about 2 percent when cycled from +23° C. to ?40° C. to +70° C. to ?40° C.

Abstract: A rack cabling system including a rack having mounted thereon a first hardware component and a patch panel housing mounted on the rack adjacent the first hardware component. The patch panel housing populates no more than a three rack unit (RU space), the patch panel housing including a front end having cable pathway openings and a rear end having connector coupler plates mounted therein. The patch panel may have a first cable pathway opening located adjacent the first side of the housing and defining a primary position and a first connector coupler plate mounted on the rear adjacent on the first side and the first connector plate having a first position corresponding to the primary position of the first cable pathway opening. Cable harnesses are routed with less than three bends of the cables between the first hardware component and the patch panel housing, so that the first cable harness is terminated at the first coupler plate in the first position.

Abstract: A fiber optic cable assembly includes a connector and a fiber optic cable. The connector includes a housing having a first axial end and an oppositely disposed second axial end. A ferrule is disposed in the housing. A plurality of optical fibers is mounted in the ferrule. The fiber optic cable includes an outer jacket defining a fiber passage that extends longitudinally through the outer jacket and a window that extends through the outer jacket and the fiber passage. First and second strength members are oppositely disposed about the fiber passage in the outer jacket. A plurality of optical fibers is disposed in the fiber passage. The optical fibers are joined at splices to the optical fibers of the connector. A splice sleeve is disposed over the splices. The splice sleeve is disposed in the window of the outer jacket.

Abstract: A bend-insensitive optical cable for transmitting optical signals includes an optical cable having a length, extending from an input end adapted to receive the optical signals, to an output end and including at least one single-mode optical fiber having a cable cut-off wavelength, of 1290 nm to 1650 nm. The at least one optical fiber is helically twisted around a longitudinal axis with a twisting pitch, for a twisted length, extending along at least a portion of the length, of the optical cable, wherein the twisted length and the twisting pitch are selected such that the optical cable exhibits a measured cut-off wavelength equal to or lower than 1260 nm. Preferably, the at least one fiber has a mode-field diameter of 8.6 ?m to 9.5 ?m. According to a preferred embodiment, the optical cable includes two optical fibers twisted together along the longitudinal axis, each of the two optical fibers having a cable cut-off wavelength of 1290 nm to 1650 nm.

Abstract: Downhole cables are described that are configured to protect internal structures that may be detrimentally impacted by exposure to the downhole environment, by protecting such structures by at least two protective layers. In some examples, the structures to be protected may be housed in a protective tube housed within the protective outer sheath. The described configuration enables the use of structures such as polymer fibers in the cables for strength and load-bearing capability by protecting the fibers, by multiple protective layers, from exposure to gases or fluids within a wellbore.

Abstract: A fiber optic cable assembly includes an outer jacket defining a first passage and a second passage disposed adjacent to the first passage. The outer jacket includes a wall disposed between an outer surface of the outer jacket and the first passage. A plurality of optical fibers is disposed in the first passage. A reinforcing member is disposed in the second passage. An access member is disposed in the wall of the outer jacket.

Abstract: Multi-fiber, fiber optic cable assemblies and related fiber optic components, cables, and methods providing constrained optical fibers within an optical fiber sub-unit are disclosed. The optical fiber sub-unit(s) comprises optical fibers disposed adjacent a sub-unit strength member(s) within a sub-unit jacket. Movement of optical fibers within a sub-unit jacket can be constrained. In this manner, the optical fibers in an optical fiber sub-unit can be held together within the optical fiber sub-unit as a unit. As a non-limiting example, the optical fiber sub-unit(s) may be exposed and constrained in a furcation assembly as opposed to the optical fibers, thereby reducing complexity in fiber optic cable assembly preparations. Constraining the optical fibers may also allow optical skew, reduction of entanglement between the optical fibers and the cable strength members to reduce or avoid optical attenuation, and/or allow the optical fibers to act as anti-buckling components within the fiber optic cable.

Abstract: An example fiber optic cable includes an outer jacket having an elongated transverse cross-sectional profile defining a major axis and a minor axis. The transverse cross-sectional profile has a maximum width that extends along the major axis and a maximum thickness that extends along the minor axis. The maximum width of the transverse cross-sectional profile is longer than the maximum thickness of the transverse cross-sectional profile. The outer jacket also defines first and second separate passages that extend through the outer jacket along a lengthwise axis of the outer jacket. The second passage has a transverse cross-sectional profile that is elongated in an orientation extending along the major axis of the outer jacket. The fiber optic cable also includes a plurality of optical fibers positioned within the first passage a tensile strength member positioned within the second passage.

Abstract: Micromodule subunit cables are constructed to allow for ease of identification between optical fibers in differing groups of optical fibers. In one cable, a first group of fibers is located within a buffer tube core while a second group of fibers is located within the cable jacket, but outside of the core. The fibers in the first and second groups can accordingly use the same color coding sequence without requiring additional indicia such as stripes or binding.