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: An optical cable has a core containing optical fibers, non-metallic peripheral reinforcements to armor the cable and a thermoplastics material outer sheath. It is fabricated by a method including successive steps of applying reinforcements to the core, extruding the sheath over the reinforcements and cooling the cable. The reinforcements are extruded onto the core as it moves through a first extruder. The combination of the core and the reinforcements is then cooled in a first cooling tank. The sheath is extruded in a second extruder downstream of the first, after which the cable is cooled in a second cooling tank downstream of the first.

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.