Abstract: An optical fiber unit includes: a plurality of optical fibers; and at least two binding materials that bind the plurality of optical fibers. The two binding materials are wound around the plurality of optical fibers in an SZ shape and adhered to each other at reversed portions of the SZ shape to form an adhesive part. The adhesive part extends along a longitudinal direction where the optical fiber unit extends, and 0.15?L/(P/2)?0.8 is satisfied where L is a length of the adhesive part in the longitudinal direction and P is a binding pitch of the two binding materials in the longitudinal direction.

Abstract: A method for manufacturing an intermittently-fixed optical fiber ribbon includes: collectively coating a plurality of optical fibers with a coating material by applying an uncured coating material that intrudes between the plurality of optical fibers and curing the intruded uncured coating material; and cutting the coating material positioned between the plurality of optical fibers at a predetermined interval in a longitudinal direction of the optical fibers with a plurality of rotary blades disposed side by side in a width direction orthogonal to the longitudinal direction, while delivering the collectively-coated optical fibers at a velocity V1 in the longitudinal direction. The velocity V1 is greater than a peripheral velocity V2 of the plurality of rotary blades.

Abstract: A method for manufacturing an optical fiber ribbon where adjacent optical fibers are intermittently connected in a length direction includes: feeding the optical fibers along the length direction; and intermittently applying a resin in the length direction by: rotating, between adjacent ones of the optical fibers, a rotating member having a recess, and blocking the resin with a peripheral edge part of the rotating member where the recess is not formed. A moving speed, in the length direction, of the peripheral edge part at a position where the peripheral edge part blocks the resin between the optical fibers is slower than a feeding speed of the optical fibers.

Abstract: An optical fiber unit includes a plurality of optical fibers; and two binding materials that bind the optical fibers. The two binding materials are wound around the optical fibers in an SZ shape, and are adhered to each other at respective reversed portions that form an adhesive part. The adhesive part has a plurality of intersection points of center lines of the two binding materials.

Abstract: An optical fiber unit includes a plurality of optical fibers; and two binding materials that bind the optical fibers. The two binding materials are wound around the optical fibers in an SZ shape, and are adhered to each other at respective reversed portions that form an adhesive part. The adhesive part has a plurality of intersection points of center lines of the two binding materials.

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 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 manufacturing an intermittently-fixed optical fiber ribbon includes: collectively coating a plurality of optical fibers with a coating material by applying an uncured coating material that intrudes between the plurality of optical fibers and curing the intruded uncured coating material; and cutting the coating material positioned between the plurality of optical fibers at a predetermined interval in a longitudinal direction of the optical fibers with a plurality of rotary blades disposed side by side in a width direction orthogonal to the longitudinal direction, while delivering the collectively-coated optical fibers at a velocity V1 in the longitudinal direction. The velocity V1 is greater than a peripheral velocity V2 of the plurality of rotary blades.

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 optical fiber unit includes: a plurality of optical fibers; and at least two binding materials that bind the plurality of optical fibers. The two binding materials are wound around the plurality of optical fibers in an SZ shape and adhered to each other at reversed portions of the SZ shape to form an adhesive part. The adhesive part extends along a longitudinal direction where the optical fiber unit extends, and 0.15?L/(P/2)?0.8 is satisfied where L is a length of the adhesive part in the longitudinal direction and P is a binding pitch of the two binding materials in the longitudinal direction.

Abstract: An optical fiber ribbon includes a plurality of optical fibers arranged side by side in a width direction. Each of the optical fibers includes a colored section that is colored by an identification color for identifying the optical fiber from the other optical fibers. The respective colored sections of the optical fibers are formed by coloring a portion, in a length direction, of the respective optical fibers according to a common pattern.

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 unit includes a plurality of optical fibers; and two binding materials that bind the optical fibers. The two binding materials are wound around the optical fibers in an SZ shape, and are adhered to each other at respective reversed portions that form an adhesive part. The adhesive part has a plurality of intersection points of center lines of the two binding materials.

Abstract: Disclosed is a method for manufacturing an intermittently connected optical fiber ribbon that includes a plurality of optical fibers arranged side by side, and connection parts arranged intermittently and each connecting two adjacent optical fibers. The method involves: a step of applying, between the optical fibers, a UV-curable resin including a siloxane structure in its molecule; a step of removing a portion of the UV-curable resin applied between the optical fibers; and a step of irradiating the UV-curable resin between the optical fibers with UV rays and forming the connection parts.

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.

Abstract: A method for manufacturing an optical fiber ribbon where adjacent optical fibers are intermittently connected in a length direction includes: feeding the optical fibers along the length direction; and intermittently applying a resin in the length direction by: rotating, between adjacent ones of the optical fibers, a rotating member having a recess, and blocking the resin with a peripheral edge part of the rotating member where the recess is not formed. A moving speed, in the length direction, of the peripheral edge part at a position where the peripheral edge part blocks the resin between the optical fibers is slower than a feeding speed of the optical fibers.

Abstract: To improve identifiability of optical fiber ribbons, an exemplary optical fiber ribbon of the invention includes: at least three optical fibers arranged side by side; and a plurality of connection parts that each connect two adjacent ones of the optical fibers, the connection parts being provided intermittently in a length direction of the optical fibers and in a width direction of the optical fibers. A marking for identifying the optical fiber ribbon is provided to each optical fiber. The position, in the circumferential direction, of the marking provided to at least one of the optical fibers is different from the position, in the circumferential direction, of the marking provided to another optical fiber.

Abstract: An optical fiber ribbon includes a plurality of optical fibers arranged side by side in a width direction. Each of the optical fibers includes a colored section that is colored by an identification color for identifying the optical fiber from the other optical fibers. The respective colored sections of the optical fibers are formed by coloring a portion, in a length direction, of the respective optical fibers according to a common pattern.

Abstract: [Objective] To detect abnormalities in optical fibers by using a phenomenon specific to optical fiber tapes including plural optical fibers arranged parallel to each other and connected together intermittently. [Solution] This optical fiber tape manufacturing method involves: a step of forming connecting parts that connect together adjacent optical fibers among a plurality of optical fibers arranged parallel to each other while applying tension to the optical fibers, and thus forming an optical fiber tape in which the connecting parts are intermittently disposed; a step of reducing the tension applied to the optical fiber tape; and a step of measuring a thickness of the optical fiber tape with reduced tension from a direction parallel to a tape plane on a path of the optical fiber tape.