Abstract: The present disclosure intends to facilitate tearing a metal sheath even in a case where the metal sheath is incorporated in an optical fiber cable. The optical fiber cable of the present disclosure includes a cable core arranged at a central portion and accommodating a plurality of optical fibers gathered together, an inner layer sheath arranged on an outer circumference of the cable core and sheathing the cable core, a metal sheath arranged on an outer circumference of the inner layer sheath and wound around the inner layer sheath, an outer layer sheath arranged on an outer circumference of the metal sheath and sheathing the metal sheath, and at least one outer sheath tearing string arranged in a longitudinal direction inside the metal sheath.

Abstract: An optical cable includes: twisted optical fiber units each including a fiber group formed by optical fibers. At least one of the optical fiber units includes a filling that wraps an outer circumference of the fiber group.

Abstract: An object is to provide a closure with a structure having a drainage function to eliminate water immersion into a coated optical fiber against temporary flooding and to prevent water from continuously contacting the coated optical fiber. Another object is to provide a closure with improved workability for opening and closing. A closure according to the present invention protects a connection part that connects a coated optical fiber enclosed in a optical fiber cable with a coated optical fiber enclosed in a optical fiber cable. The closure includes a coated optical fiber housing that divides an interior of the closure into a first space that is on a side of a road and has a main body cable insertion hole for inserting the optical fiber cables from an exterior and a second space that is on an opposite side of the road and includes the connection part.

Abstract: An optical cable according to the present disclosure has a structure in which at least one or more optical fiber cores and an interposition that prevents optical fibers from coming into contact with each other are bundled by a bundle tape.

Abstract: An optical fiber cable of the present disclosure is formed by assembling a plurality of drop optical cables, and each of the drop optical cables has a structure where at least one or more optical fiber cores and a tension fiber or a tension member is embedded in a sheath such that the drop optical cable has two or more axes each having a minimum value of a second moment of area with respect to arbitrary neutral planes, and even an optical cable obtained by assembling drop optical cables has a structure having two or more axes each having a minimum value of the second moment of area with respect to arbitrary neutral planes.

Abstract: The object of the present disclosure is to provide an optical fiber cable having a large contact area with the bottom surface of a rectangular groove and easily bent in at least two directions, as compared to an optical fiber cable having a circular cross-sectional shape perpendicular to a long axis direction. Therefore, the optical fiber cable of the present disclosure has three or more flat side surfaces in the long axis direction and two or more axes each having a minimum moment of inertia of area with respect to neutral planes.

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 object is to provide a closure with a structure having a drainage function to eliminate water immersion into a coated optical fiber against temporary flooding and to prevent water from continuously contacting the coated optical fiber. Another object is to provide a closure with improved workability for opening and closing. A closure according to the present invention protects a connection part that connects a coated optical fiber enclosed in a optical fiber cable with a coated optical fiber enclosed in a optical fiber cable. The closure includes a coated optical fiber housing that divides an interior of the closure into a first space that is on a side of a road and has a main body cable insertion hole for inserting the optical fiber cables from an exterior and a second space that is on an opposite side of the road and includes the connection part.

Abstract: An object of the present disclosure is to provide a method of laying an optical cable that is capable of laying and removing the optical cable in a stable place without civil engineering works. To achieve the above-mentioned object, a method of laying an optical cable according to the present disclosure includes laying the optical cable and two laying strips on a road surface or a wall surface so that the optical cable is sandwiched between side surfaces of the two laying strips.

Abstract: An optical cable includes: twisted optical fiber units each including a fiber group formed by optical fibers. At least one of the optical fiber units includes a filling that wraps an outer circumference of the fiber group.

Abstract: A method of laying an optical cable according to the present disclosure includes: installing a laying strip, in which the optical cable is to be embedded, on a road surface or a wall surface; forming a cut line, for embedding the optical cable, on the installed laying strip; and embedding the optical cable in the formed cut line.

Abstract: The present disclosure intends to facilitate tearing of a metal sheath even in a case where the metal sheath is incorporated in an optical fiber cable. The optical fiber cable of the present disclosure includes a cable core arranged at a central portion and accommodating a plurality of optical fibers gathered together, an inner layer sheath arranged on an outer circumference of the cable core and sheathing the cable core, a metal sheath arranged on an outer circumference of the inner layer sheath and wound around the inner layer sheath, an outer layer sheath arranged on an outer circumference of the metal sheath and sheathing the metal sheath, and at least one outer sheath tearing string arranged in a longitudinal direction inside the metal sheath.

Abstract: An optical fiber cable includes: a cable body having a core and an inner sheath that accommodates the core; a reinforcing sheet that surrounds the cable body; an outer sheath that accommodates the cable body and the reinforcing sheet; and an outer ripcord that is embedded in the inner sheath. The inner sheath includes a projection that projects outwardly in a radial direction of the optical fiber cable. At least part of the outer ripcord is disposed inside the projection.

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 cable includes: a cable body having a core and an inner sheath that accommodates the core; a reinforcing sheet that surrounds the cable body; an outer sheath that accommodates the cable body and the reinforcing sheet; and an outer ripcord that is embedded in the inner sheath. The inner sheath includes a projection that projects outwardly in a radial direction of the optical fiber cable. At least part of the outer ripcord is disposed inside the projection.

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.