Abstract: An optical fiber arrangement method includes: preparing an intermittently connected optical fiber ribbon including optical fibers arranged side by side at a first pitch larger than a fiber diameter; holding a non-connecting region of the optical fiber ribbon with a holder, wherein connecting portions of the optical fiber ribbon intermittently connect the optical fibers extending out from the holder to each other; changing a width of the optical fiber ribbon in an interior of the holder; and arranging the optical fibers, extending out from the holder, with intervals of the optical fibers changed from the first pitch to a second pitch smaller than the first pitch by removing the connecting portions in a holding state where the holder is holding the optical fibers.

Abstract: An optical fiber arrangement method includes: preparing an intermittently connected optical fiber ribbon including optical fibers arranged side by side at a first pitch larger than a fiber diameter; holding a non-connecting region of the optical fiber ribbon with a holder, where connecting portions intermittently connect the optical fibers extending out from the holder to each other; changing a width of the optical fiber ribbon in an interior of the holder; and arranging the optical fibers, extending out from the holder, with intervals of the optical fibers changed from the first pitch to a second pitch smaller than the first pitch by removing the connecting portions in a state where the holder is holding the optical fibers.

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: a sheath; and a core including twisted optical fibers disposed in an accommodation space in the sheath. Each of the twisted optical fibers includes: a glass portion, a primary layer that covers the glass portion, and a secondary layer that covers the primary layer. A fiber pulling force when pulling out the twisted optical fibers is equal to or greater 15 N/10 m. A value of an index Q is less than 20.

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 intermittently connected optical fiber ribbon includes optical fibers, disposed side by side in a width direction of the optical fibers, and connecting portions that each intermittently connect two adjacent ones of the optical fibers. A center-to-center distance between any of the two adjacent ones of the optical fibers is greater than a diameter of the individual optical fibers. A total volume shrinkage per meter per 1° C. of the connecting portions of a single one of the optical fibers is 0.00070 mm3/m·° C. or lower.

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 arrangement method includes: preparing an intermittently connected optical fiber ribbon including optical fibers arranged side by side at a first pitch larger than a fiber diameter; holding a non-connecting region of the optical fiber ribbon with a holder, where connecting portions intermittently connect the optical fibers extending out from the holder to each other; changing a width of the optical fiber ribbon in an interior of the holder; and arranging the optical fibers, extending out from the holder, with intervals of the optical fibers changed from the first pitch to a second pitch smaller than the first pitch by removing the connecting portions in a state where the holder is holding the optical fibers.

Abstract: An intermittently connected optical fiber ribbon includes optical fibers, disposed side by side in a width direction of the optical fibers, and connecting portions that each intermittently connect two adjacent ones of the optical fibers. A center-to-center distance between any of the two adjacent ones of the optical fibers is greater than a diameter of the individual optical fibers. A total volume shrinkage per meter per 1° C. of the connecting portions of a single one of the optical fibers is 0.00070 mm3/m·° C. or lower.

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: 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: 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 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 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 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 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: 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: 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.