Abstract: An optical fiber branch cable is provided that comprises a branch portion disposed stably with respect to a multi-core optical fiber cable of a trunk line from which branching is performed, that is excellent in handleability as a cable, and that exhibits high workability. In the optical fiber branch cable of the invention, in a middle of a multi-core optical fiber cable 2 of a trunk line, a branch portion 11 is disposed. The branch portion 11 has: a base member 16 which is attached so as to cover a tensile-strength wire 9 in a portion where a cable jacket 10 of the multi-core optical fiber cable 2 is removed away; a multi-core optical connector 30 which is connected to the tip end of a tape unit 4 drawn out from the multi-core optical fiber cable 2; an extra-length housing portion 18 which houses an extra length of the tape unit 4 to which the multi-core optical connector 30 is connected; and a connector attaching portion 19 to which the multi-core optical connector 30 is attachable in a plural number.

Abstract: Grating built-in type optical fiber couplers and optical amplifiers form a multiplexer for efficiently effecting multiplex separation of a specific wavelength without using an optical circulator. A function to add a signal of specific wavelength efficiently can be realized. Additionally, the device is inexpensive.

Abstract: A device for winding an optical fiber cable comprises a case formed in the shape of a box, having an axle hole at a center portion of an upper surface thereof; an insertion hole provided substantially central portion of an upper surface and both of sidewalls so as to insert the optical fiber cable so that it pass through into the case; and a drum further including; a winding drum for winding the optical fiber cable provided rotatably into the case so that the optical fiber cable can be wound with bend in a condition that it is not harmed for the characteristic of the optical fiber cable; a flange one of formed integrally and fixed to an upper part of the winding drum, having a guide part that guides end portions of the optical fiber cable to the winding drum after the optical fiber cable is inserted into the insertion hole of the case; a pair of guide drums one of formed integrally and fixed to an upper part of the flange through the space, capable of inserting the optical fiber cable therein; and a rotation

Abstract: A device for winding an optical fiber cable comprises a case formed in the shape of a box, having an axle hole at a center portion of an upper surface thereof; an insertion hole provided substantially central portion of an upper surface and both of sidewalls so as to insert the optical fiber cable so that it pass through into the case; and a drum further including; a winding drum for winding the optical fiber cable provided rotatably into the case so that the optical fiber cable can be wound with bend in a condition that it is not harmed for the characteristic of the optical fiber cable; a flange one of formed integrally and fixed to an upper part of the winding drum, having a guide part that guides end portions of the optical fiber cable to the winding drum after the optical fiber cable is inserted into the insertion hole of the case; a pair of guide drums one of formed integrally and fixed to an upper part of the flange through the space, capable of inserting the optical fiber cable therein; and a rotation

Abstract: A device for winding the remaining line of the optical fiber cable easily when wiring without lose the characteristics of the optical fiber cable. The device includes a case body having an insertion aperture, an inner drum, and a pair of outer drums for receiving cable wound thereabout. The inner drum includes an upper flange, a lower flange, and a pair of guide drums disposed between the upper flange and the lower flange.

Abstract: Wirings of optical fiber cable to a building having at least one story including optical core wires or taped optical core wires including at least one wire for use on each story and at least one reserve wire for use on each story upon a change in demand. The wires are wired such that a center portion is situated at an upper portion of the building and both ends are situated at a lower portion of the building. A connector part is arranged in each story and connected to the optical core wires or taped optical core wires for use on that story.

Abstract: Without performing serious work of connection by connector attachment etc. on the spot, it can operate at a factory and the principal cable can be wired using the branch implement that can be attached by easy work on the spot. In addition, the ratio of the number of optical core wires of the external wiring in reserve and the branch cable for stories can be freely chosen, and change when demand change arises and the increase in a circuit can also be performed very easily.

Abstract: A device for winding winds the remaining line of the optical fiber cable easily when wiring without lose the characteristics of the optical fiber cable.

Abstract: A flat optical fiber cable is composed of an optical fiber ribbon cord which is comprised of tensile strength fiber having a rectangular shape covering an outside circumferential part of several optical fiber cores which are parallel one another and a sheath covers an outside circumferential part of the tensile strength fiber. The tension member is parallel to both sides of the optical fiber ribbon cord forming a row, and the outside circumferential part of the tension member and the optical fiber ribbon cord is covered with a sheath having a nearly oval shape. Because the flat optical fiber cable is formed in this way, it is easy to construct and assemble terminals and damage to the optical fiber and deterioration of performance is prevented.

Abstract: An optical fiber core consists of an optical fiber, an ultraviolet curable resinous layer which covers an outside circumferential part of an optical fiber, and a covering layer covering an outside circumferential part of ultraviolet curable resinous layer. In addition, the covering layer is composing of a first covering layer using flexible thermoplastic resin and second covering layer using thermoplastic resin of semi-hard or hard material in order that it sufficiently fulfills squeezing, tensile, bending, temperature, and lateral pressure characteristics and an economic efficiency.

Abstract: At least an optical fiber of more than two pieces are arranged at least a tension member or more in a row, and the outside circumferential part of tension member and optical fiber is covered with a sheath so as to become a nearly oval shape. In addition, at least a torn slot or more is formed the outside circumferential part of a sheath. Therefore, it can be cut the end part of a sheath simply at the time of terminal management without the fact that an optical fiber makes damage and is added to power.