Abstract: A cable comprises a leakproof tube containing at least one optical fiber together with a filler material which holds the fiber(s) in place inside the tube and which provides the tube with longitudinal sealing. The filling ratio of the fiber-holding material is less than a determined limit so as to provide at least one expansion volume inside the tube so that the partial pressure of hydrogen remains low enough to avoid giving rise to significant attenuation in the transmission properties of the optical fiber.

Abstract: The invention relates to apparatus for depositing a lubricant coating on a cable, the cable including a sheath made by means of an extruder followed by a cooling vessel. Downstream from the cooling vessel, the apparatus includes a heater member followed by a deposition chamber for depositing a lubricant material.

Abstract: An optical fiber cable constituted by a single tube defining an internal bore housing at least one optical fiber and whose wall incorporates a reinforcement zone. The reinforcement zone is constituted by a thermoplastic material giving the cable both flexibility and resistance against compression and impact.

Abstract: An optical unit (5a, 5b) comprising a plurality of optical fibers (2) grouped together in a tube (3a, 3b) and optionally assembled into one or more ribbons inside tube. The tube (3a, 3b) has a Young's modulus less than 200 MPa and a Shore A hardness less than 90 at a temperature of approximately +20.degree. C. and a Young's modulus less than 2000 MPa at a temperature of approximately -40.degree. C. A fiber optic cable (10, 20) comprising at least one such optical unit (5a, 5b). Application of the cable to telecommunications.

Abstract: A fiber optic cable comprises, in a sheath, a tube in which the optical fibers are disposed and a single reinforcing member. These components are arranged so that the neutral axis of the tube and that of the cable coincide.

Abstract: A method and apparatus for covering a ribbon of optical fibers with a resin. The resin is polymerizable under the effect of UV radiation and forms a protective covering surrounding and holding the fibers. The method includes a pre-polymerization step during which the coated fibers advance through a UV irradiating chamber having a pre-polymerization ultraviolet radiation power of less than one fourth of the total power required to polymerize the resin, which is just sufficient to initiation polymerization. This step is followed by a polymerization finishing step during which the pre-polymerized ribbon is subjected to UV radiation of higher power than the radiation produced during the pre-polymerization step, which completes the polymerization process.

Abstract: The present invention relates to a method of manufacturing a cable containing optical fibers, the cable including an optical core assembly surrounded by a plurality of mechanical reinforcing members made of a plastics material reinforced with reinforcing fibers, referred to as an "FRP" material, the reinforcing members being disposed helically around said core assembly so as to form a reinforcing tube, said reinforcing members having a thermal expansion coefficient that is lower than those of the remaining portions of said cable and a Young's modulus that is higher than those of the remaining portions of said cable other than said optical fibers.

Abstract: The protected and individualized fibers of the optical fiber ribbon are encapsulated in a common outside covering. The protected fibers carry distinctive sets of ink marks on their outside surfaces in order to individualize them, and they are individually covered with respective films of transparent polymerizable resin containing an anti-adhesive agent, with the common covering being received on the films. The ribbon is suitable for optical fiber cables.

Abstract: An optical fiber moisture sensor comprising a mechanical system having a stationary jaw and a moving jaw between which said fiber is mounted, the sensor also including an element made of moisture-sensitive material coupled to said moving jaw to allow it to be urged towards said stationary jaw in the presence of moisture, thereby applying compression to said optical fiber, wherein said element is made of a material that looses mechanical strength with increasing moisture and that is mounted to oppose the action of resilient means urging said moving jaw towards said stationary jaw.

Abstract: An optical fiber cable capable of withstanding a jump in temperature to 350.degree. C. for a short period of time, the cable comprising:(a) at least one carrier element of a composite of glass fiber and thermosetting resin;(b) an optical fiber support constituted by a grooved rod surrounding the carrier element, or a tube preferably provided with carrier elements in its thickness, or by compact structure fibers, the rod or tube being made of a thermoplastic polymer;(c) optical fibers disposed in the grooves of the rod or inside the tube;(d) a viscous material filling the grooves or the tube around the optical fibers;(e) an envelope constituted by a tape of thermoplastic polymer;wherein the grooved rod or the tube, or the secondary coating of compact structure fibers, is made of cross-linked polyethylene, wherein the viscous material filling the grooves is a silicon resin, and wherein the thermoplastic polymer of the envelope is a polyimide resin.

Abstract: The end (2) of an axial strength member is curved into a swan-neck (3) and gripped in a cold polymerized resin (4) which fills a cavity of a chamber (5) that is fixed relative to the junction box (6).

Abstract: A connection between a junction box and an optical fiber cable having an axial strength member, said strength member being constituted by braided fibers or by a composite material including fibers, e.g. a guard cable for a high tension line. The fibers of the axial strength member (2) are splayed out into a tuft (4) at the end (3) of the cable and are held fast in a cold-polymerized resin (5) which fills a cavity in a receptacle (6) which is fixed to said box.

Abstract: A polymer material which contains ethylene groups and is made fireproof by an organic brominated additive, antimony oxide and optionally a phosphate or pyrophosphate containing titanate. It contains:(a) a non-reticulated polymer matrix containing 40% to 60% by weight of polyethylene and 40% to 60% by weight of a copolymer of ethylene and of alkyl acrylate;(b) 25% to 35% by weight related to the weight of the polymer matrix of the organic brominated additive which is decabromodiphenyloxide, octabromodiphenyl or hexabromodiphenyl;(c) 8% to 19% by weight related to the weight of the polymer matrix of antimony oxide(d) and optionally 0.1% to 0.5% by weight related to the weight of the polymer matrix of an organo phosphate containing a phosphate or pyrophosphate radical.