The present invention relates to an optical fiber ribbon, comprising a plurality of adjacent optical fiber units extending in a longitudinal direction and arranged in parallel forming an optical fiber assembly having a width, each of the optical fiber units comprising either a single fiber or a group of at most three optical fibers, preferably two optical fibers, encapsulated with a matrix material; and a plurality of successive elongated rectilinear beads of a bonding material being arranged along a length of said assembly; each of said plurality of beads being configured to form an elongated bond between two adjacent optical fiber units of the plurality of optical fiber units; wherein a first bead forming a first bond connects a first pair of adjacent optical fiber units while the successive bond formed by the successive bead, connects a further pair of adjacent optical fiber units, wherein at least one optical fiber unit of the further pair differs from the optical fiber units of the first pair; wherein at each longitudinal position of the optical fiber assembly there is at most one bond. The present invention moreover relates to a method of producing such an optical fiber ribbon. A fluorescent tracer is present in the beads.

A rollable optical fiber ribbon utilizing low attenuation, bend insensitive fibers and cables incorporating such rollable ribbons are provided. The optical fibers are supported by a ribbon body, and the ribbon body is formed from a flexible material such that the optical fibers are reversibly movable from an unrolled position to a rolled position. The optical fibers have a large mode filed diameter, such as ≥9 microns at 1310 nm facilitating low attenuation splicing/connectorization. The optical fibers are also highly bend insensitive, such as having a macrobend loss of ≤0.5 dB/turn at 1550 nm for a mandrel diameter of 15 mm.

An electronic device may have a display, a display cover layer, and a sheet-packed coherent fiber bundle. The coherent fiber bundle may have an input surface that receives an image from the display and a corresponding output surface to which the image is transported. The coherent fiber bundle may be placed between the display and the display cover layer and mounted to a housing. The coherent fiber bundle may have fiber cores with bends that help conceal the housing from view and make the display appear borderless. The coherent fiber bundle has filaments formed from elongated strands of binder in which multiple fiber cores are embedded. Sheets of filaments are stacked and fused together to form the coherent fiber bundle. By aligning and fusing the sheets with respect to each other the filaments are packed with a desired density and uniformity.

Provided is an optical fiber having identification mark, which includes an optical transmission medium (exemplified by glass fiber) including a core part and a cladding part, a primary resin layer coating the optical transmission medium, and a secondary resin layer coating the primary resin layer, in which identification marks for optical fiber identification (exemplified by continuous identification mark) are provided on a surface of the secondary resin layer at a predetermined interval along an axial direction of the optical transmission medium. An effective area of the optical transmission medium at a wavelength of 1550 nm is 90 μm.sup.2 or more, the predetermined interval is 100 mm or more and 500 mm or less, and a Young's modulus of the primary resin layer is 0.9 MPa or less.

A method of preparing a preformed fiber optic circuit for later termination to at least one fiber optic connector includes providing a substrate for supporting a plurality of optical fibers, the substrate including at least one layer of flexible foil, wherein the flexible foil may be formed from polyethylene terephthalate (PET) according to one example and peeling a layer including at least the optical fibers from the at least one layer of flexible foil.

An optical fiber unit includes: a first optical fiber ribbon that intermittently connects a first plurality of optical fibers; a second optical fiber ribbon that intermittently connects a second plurality of optical fibers; and interlayer connection parts that intermittently connect the first optical fiber ribbon and the second optical fiber ribbon in a length direction while the first optical fiber ribbon and the second optical fiber ribbon are layered and arranged. The first optical fiber ribbon and the second optical fiber ribbon are layered and arranged such that optical fibers having a same fiber number of the first optical fiber ribbon and the second optical fiber ribbon are aligned in a up-down direction perpendicular to the length direction.

Embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes a cable jacket having an inner jacket surface and an outer jacket surface. The outer jacket surface is an outermost surface of the optical fiber cable, and the inner jacket surface defines an internal jacket bore. The optical fiber cable also includes at least one subunit disposed within the internal jacket bore. Each of the at least one subunit includes a foamed tube having an inner subunit surface and an outer subunit surface. The inner subunit surface defines a central subunit bore. Each of the at least one subunit also includes a stack of at least two optical fiber ribbons disposed in the central subunit bore of the foamed tube. Each of the at least two optical fiber ribbons comprising at least two optical fibers. The stack occupies from 85%-95% of a cross-sectional area of the central subunit bore such that the central subunit bore provides from 5% to 15% of free space around the stack along at least a portion of a length of the foamed tube.

An optical fiber ribbon is configured by arranging in parallel and coupling a plurality of single-core optical fibers. The optical fibers adjacent to each other are intermittently bonded by coupling parts at predetermined intervals in the longitudinal direction of the optical fiber ribbon. The coupling parts adjacent to each other in the width direction are disposed to be displaced from each other in the longitudinal direction of the optical fiber ribbon. In the optical fiber ribbon, the adjacent optical fibers are intermittently coupled by the coupling parts in the longitudinal direction, and the amounts of resin of the coupling parts are not uniform in the longitudinal direction of the optical fibers. Moreover, the Young's modulus of resin constituting the coupling part is preferably 130 MPa or less, and more preferably 80 MPa or less.

An optical fiber cable includes a slot rod that is provided with a plurality of slot grooves in a spiral shape stranded in one direction, a tensile strength member that is provided inside the slot rod to receive tension, a cable sheath that covers an outer side of the slot rod, and a plurality of optical units made by gathering optical fiber ribbons in which a plurality of optical fibers is arranged in parallel. In each of the optical units, the optical fiber ribbons are stranded with each other along a longitudinal direction of the optical fiber cable. Each of the optical units is accommodated in corresponding one of the slot grooves along the longitudinal direction in a state where relative positional relationships between the optical units and the slot grooves are kept and relative positional relationships between the optical units are kept.

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.