Abstract: An optical fiber protective unit includes: a reticulated tube; and a tubular member that is inserted through the reticulated tube and that is configured to accommodate a plurality of optical fibers. The reticulated tube is disposed on an outer periphery of the tubular member in a state folded in a longitudinal direction. Both end parts of the reticulated tube are located on the outer periphery of the tubular member.

Abstract: An optical fiber cable includes: optical fiber units each comprising optical fibers, and twisted together in an SZ shape; a wrapping tube that wraps around the optical fiber units; fillings disposed inside the wrapping tube, wherein the fillings include at least one first filling and at least one second filling that are located between two adjacent optical fiber units; and a sheath that covers the wrapping tube. The first filling is in contact with the wrapping tube. The second filling is located more radially inward than the first filling in a radial direction.

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: An optical fiber protective unit includes: a reticulated tube; and a tubular member that is inserted through the reticulated tube and that is configured to accommodate a plurality of optical fibers. The reticulated tube is disposed on an outer periphery of the tubular member in a state folded in a longitudinal direction. Both end parts of the reticulated tube are located on the outer periphery of the tubular member.

Abstract: A reticulated tube includes: a plurality of openings that are reticulately formed; peripheral parts that form the openings; and a branch part that is formed in a boundary of three or more openings. The branch part includes three or more peripheral parts extending from the branch part. The reticulated tube is configured to accommodate a plurality of optical fibers inserted through the reticulated tube. The peripheral parts are restricted by the branch part and are bendable.

Abstract: An elongated-object drum includes: a drum on which an elongated object is wound; and a management module that is attached to the drum and comprises: an acceleration sensor that detects acceleration of the drum, a computation device that performs computation based on a detection result from the acceleration sensor, and a storage device that stores a computation result obtained by the computation device based on the detection result from the acceleration sensor.

Abstract: An optical fiber cable includes a core that includes an assembled plurality of optical fibers; an inner sheath that accommodates the core therein, a pair of tension members that are embedded in the inner sheath and that are disposed on opposite sides of the core, and an outer sheath that covers the inner sheath. The inner sheath is formed with a dividing portion that divides an inner peripheral surface and an outer peripheral surface of the inner sheath in a circumferential direction. The dividing portion extends along a longitudinal direction in which the optical fiber cable extends.

Abstract: A method for manufacturing an optical fiber ribbon includes: forming a colored layer on to each of a plurality of optical fibers and forming an optical fiber ribbon by curing a connecting material applied to a surface of the colored layer of each of the optical fibers to form connection parts that connect adjacent ones of the optical fibers. Forming the colored layer further includes: applying a coloring agent to the optical fibers and curing the coloring agent such that uncured resin remains on the surface of the colored layer. Forming the optical fiber ribbon further includes: applying the connecting material to the surface with the uncured resin and curing the connecting material and the uncured resin on the surface of the colored layer.

Abstract: An intermittent connection-type optical fiber ribbon including: optical fibers aligned in a width direction of the intermittent connection-type optical fiber ribbon; and a connection part disposed between two separation spaces that are aligned in a lengthwise direction of the intermittent connection-type optical fiber ribbon and that separate adjacent ones of the optical fibers. A percentage content of the air bubbles is equal to or less than 15.5%. The percentage content of the air bubbles is a proportion of a total area of the air bubbles contained in the connection part to an area of the connection part in a section acquired by cutting the intermittent connection-type optical fiber in the width direction.

Abstract: A reticulated tube includes: a plurality of openings that are reticulately formed; peripheral parts that form the openings; and a branch part that is formed in a boundary of three or more openings. The branch part includes three or more peripheral parts extending from the branch part. The reticulated tube is configured to accommodate a plurality of optical fibers inserted through the reticulated tube. The peripheral parts are restricted by the branch part and are bendable.

Abstract: An optical fiber cable includes a core that includes an assembled plurality of optical fibers; an inner sheath that accommodates the core therein, a pair of tension members that are embedded in the inner sheath and that are disposed on opposite sides of the core, and an outer sheath that covers the inner sheath. The inner sheath is formed with a dividing portion that divides an inner peripheral surface and an outer peripheral surface of the inner sheath in a circumferential direction. The dividing portion extends along a longitudinal direction in which the optical fiber cable extends.

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: A method for manufacturing an optical fiber ribbon includes: forming a colored layer on to each of a plurality of optical fibers and forming an optical fiber ribbon by curing a connecting material applied to a surface of the colored layer of each of the optical fibers to form connection parts that connect adjacent ones of the optical fibers. Forming the colored layer further includes: applying a coloring agent to the optical fibers and curing the coloring agent such that uncured resin remains on the surface of the colored layer. Forming the optical fiber ribbon further includes: applying the connecting material to the surface with the uncured resin and curing the connecting material and the uncured resin on the surface of the colored layer.

Abstract: An optical fiber cable includes: a core comprising gathered optical fibers; an inner sheath housing the core; a wire body embedded in the inner sheath; tension members embedded in the inner sheath, wherein the core is interposed between the tension members; a reinforcing sheet that covers the inner sheath; and an outer sheath that covers the reinforcing sheet, wherein in the inner sheath, ti<Ti and to<To are satisfied, where a thickness of a radially inner portion between the core and the wire body is ti, a thickness of a radially inner portion between the core and each of the tension members is Ti, a thickness of a radially outer portion between the wire body and the reinforcing sheet is to, a thickness of a radially outer portion between each of the tension members and the reinforcing sheet is To.

Abstract: An optical fiber ribbon is formed by connecting a plurality of optical fiber colored core wires to each other with a connector formed of a UV curable resin. Each of the optical fiber colored core wires includes: a bare optical fiber; a primary layer that comprises a UV curable resin that covers the bare optical fiber; a secondary layer that comprises a UV curable resin that covers the primary layer; and a colored layer disposed outside the secondary layer and that comprises a colored UV curable resin. The primary layer has a Young's modulus that is greater than or equal to 75% of a saturated Young's modulus of the primary layer.

Abstract: An optical fiber colored core wire includes: a bare optical fiber; a primary layer that comprises a UV curable resin that covers the bare optical fiber; a secondary layer that comprises a UV curable resin that covers the primary layer; and a colored layer disposed outside the secondary layer and that comprises a colored UV curable resin. The primary layer has a Young's modulus that is greater than or equal to 70% of a saturated Young's modulus of the primary layer.

Abstract: An intermittent connection-type optical fiber ribbon including: optical fibers aligned in a width direction of the intermittent connection-type optical fiber ribbon; and a connection part disposed between two separation spaces that are aligned in a lengthwise direction of the intermittent connection-type optical fiber ribbon and that separate adjacent ones of the optical fibers. A percentage content of the air bubbles is equal to or less than 15.5%. The percentage content of the air bubbles is a proportion of a total area of the air bubbles contained in the connection part to an area of the connection part in a section acquired by cutting the intermittent connection-type optical fiber in the width direction.

Abstract: An optical cable includes: an optical fiber unit where a plurality of optical fibers are wrapped with a wrapping tape; at least three tensile strength members disposed in parallel with and on an outer side of the optical fiber unit at intervals in a circumferential direction; and a sheath that coats the optical fiber unit and the tensile strength members and that is disposed between the optical fiber unit and the tensile strength members. An inner wall surface of the sheath formed between the optical fiber unit and the tensile strength members protrudes toward a cable center in comparison with an inner wall surface of the sheath where none of the tensile strength members are disposed. A portion of the wrapping tape disposed on the inner wall surface that protrudes toward the cable center is depressed toward the cable center.

Abstract: An inspection device of an optical fiber unit, including a plurality of binding materials wound in an SZ shape on a plurality of optical fibers, includes: a measurement sensor that measures a width of the optical fiber units in a first direction orthogonal to a longitudinal direction in which the optical fiber unit extends; and a determination circuit that determines a presence or an absence of an abnormality in a binding state, based on a measurement result of the measurement sensor.

Abstract: A method for inspecting an intermittent connection type optical fiber ribbon includes: accumulating one-dimensional images in a width direction of the intermittent connection type optical fiber ribbon, arranged intermittently with connection parts that connect adjacent optical fibers by repeatedly capturing images of the intermittent connection type optical fiber ribbon along the width direction while moving the intermittent connection type optical fiber ribbon in a longitudinal direction; and creating a two-dimensional image of the intermittent connection type optical fiber ribbon by aligning the one-dimensional images in a second direction orthogonal to a first direction where pixels configuring the one-dimensional image are aligned.