Abstract: The invention relates to an optical fiber cable including an outer sheath containing a plurality of optical fibers separated into at least two optical fiber modules, each of said modules consisting of a module sheath surrounding a respective group of optical fibers. According to the invention, the module sheath is formed by a film of plastics material. The film is, for example, wrapped widthwise around the group of optical fibers, a first face of the film being superposed on and fixed to a second face of the film over a portion of given width of said film.

Abstract: The method includes axially modulating at least one plasma build-up pass in order to improve the opto-geometrical properties of the preform. The modulation preferably takes place during the final passes of plasma build-up and takes place by modulating the build-up grain flow rate. The diameter of the preform is evaluated (6), and a build-up control device (8) regulates grain flow rate (11, 5) in application of the above method.

Abstract: The present invention relates to an optical fiber (1) comprising an optical core (2) for guiding the majority of the lightwaves transmitted by the fiber, and surrounded by optical cladding (3), itself surrounded by a protective covering (4) of a plastics material, characterized in that the plastics material (4) is a reversibly cross-linked material.

Abstract: The present invention aims to obtain a simplified connection system for high voltage power cables having ratings up to 400 KV and above. There is obtained a common cable connection system for all accessories and interconnection. The connection system uses a generally applicable interface (4, 5, 6; 13, 14, 15; 30, 40) for interconnection with a number of different apparatus and includes a cable termination (30) consisting of an elastomeric body (36), integrated therein a stress relief device (34), a connector shield (35), an insulation having a conical interface surface (37) and an outer conductive screen (39) and a rigid insulator (41) having a conical interface surface (42) corresponding to the interface surface (37) of the cable termination (30).

Abstract: The invention relates to apparatus for curing an object by using UV radiation, the object being made, at least in part, of a material that is cross-linkable under UV radiation, said apparatus including: UV radiation sources (2); a tube (3) made of a material that is permeable to UV radiation, the tube being surrounded by the UV radiation sources (2), and being designed to receive at least a portion of the object to be cured; and gas feed means for generating a gas flow (15) through the tube (3) along a general flow axis (9). According to the invention, the apparatus further includes channeling means (4) for causing a portion (16) of the gas flow (15) to constitute a gas screen sweeping the inside sidewall (5) of the tube (3).

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 concerns a method of manufacturing an optical-fiber module including a plurality of optical fibers assembled and held together by a flexible resin, said method including a resin-application step in which said flexible resin is applied to the entire set of said fibers which are disposed parallel to one another so that their longitudinal axes lie in substantially the same plane;wherein said resin-application step is followed by the following steps:partially cross-linking said resin so as to obtain a ribbon;rolling up said ribbon by bringing together its longitudinal edges so as to give it a shape that is substantially cylindrical; andfully cross-linking said resin so as to maintain the cylindrical shape of the rolled-up ribbon.

Abstract: The present invention concerns an optical fiber cable containing a plurality of optical fibers split up into modules, each module being covered with a supporting sheath in contact with the outer optical fibers of the module so as to hold the optical fibers contained in said module tightly so that they are mechanically coupled to one another, the entire set of modules being disposed inside a covering made of an insulating material, which covering is in contact with the outer modules of the set of modules so as to form a compact assembly comprising all of the modules;wherein each optical fiber has a cut-off wavelength of not more than 1,350 nm, and, at a wavelength in the vicinity of 1,550 nm, has a mode field diameter lying in the range 7 .mu.m to 9 .mu.m, and wherein each optical fiber is provided with a substantially hermetic coating on its optical cladding.

Abstract: The present invention relates to a method of detecting and/or measuring changes in a physical magnitude by means of a distributed sensor, changes being detected and/or measured at a plurality of "measurement" points along said sensor, said sensor comprising an optical fiber having an optical core for guiding the majority of light waves, said optical core including a plurality of diffraction gratings distributed along said optical fiber, each situated at one of said measurement points, said diffraction gratings all having substantially the same central reflection wavelength in the absence of strain, the method comprising the following steps: injecting a "detection" light signal into an "inlet" end of said optical fiber, the wavelength of the light signal being close to said central reflection wavelength; determining the power of one of the reflected signals, referred to as the "detected reflected power", as a function of time; comparing said detected reflected power as a function of time with the power reflect

Abstract: The present invention concerns an optical-fiber cable containing at least one optical-fiber module including a plurality of optical fibers assembled and held together by a flexible resin so as to define a ribbon, the ribbon inside the cable being rolled up so that its longitudinal edges substantially touch each other, and so that it is substantially cylindrical in shape, wherein the flexible resin is applied asymmetrically relative to the midplane of the ribbon in the unrolled state, which midplane contains all of the longitudinal axes of the fibers, and wherein the ribbon is rolled up by bringing its longitudinal edges together so that the majority of the resin is located inside the convex volume defined, when the ribbon is in the rolled-up state, by the surface that contains all of the longitudinal axes of the fibers.

Abstract: A polymeric resin for optical fiber strips is formed from a mixture comprising a first base polymer selected from an epoxy acrylate and a urethane acrylate and a copolymer in a proportion of between 0.5% and 20% by weight of said mixture which is compatible with said first polymer and carries polysiloxane chains.

Abstract: A method of verifying that a given insulative element conforms with a reference insulative element, comprising the steps of: emitting a primary beam of electrons impinging on the given insulative element, receiving a secondary beam of electrons returned by the given insulative element in response to emission of the primary beam of electrons, and comparing a curve as a function of time of the electrical current of the secondary beam received with a curve as a function of time of a reference electrical current to establish whether or not the given insulative element conforms to a reference insulative element.

Abstract: An optical-fiber cable containing at least one optical member, and at least one strength member constructed such that members are inserted in respective hollow cavities within a covering made of thermoplastic. The cavities are closed relative to the outside of the cable, and all the cavities receiving optical members communicate with one another, with at least two of the cavities communicating with each other. The members contained in the cavities that communicate with each other are coated with a viscous, non-adhering coating material preventing them from adhering to the thermoplastic covering so that the covering defines a central portion having at least two branches, the central portion containing no thermoplastic and being filled with the coating material. Each branch is terminated at one of its ends by a respective cavity communicating with other cavities and having its other end joined to the other ends of the other branches.

Abstract: An optical fiber cable comprises a stacked plurality of optical fiber ribbons each including a plurality of optical fibers disposed side by side in substantially the same plane and all embedded in a common covering or matrix of the ribbon. A protective outer sheath protects the cable against radial compression loads. Reinforcing members withstand traction loads applied to the cable, which further comprises filler members of a material based on reinforcing fibers and having a coefficient of expansion similar to that of the optical fibers embedded in a connecting matrix. The filler members occupy all or part of a volume delimited by the outside surface of the stacked ribbons and by the inside surface of the outer sheath so that the combination of the stack and the filler members has an external contour in cross-section that is substantially circular. The filler members protect the ribbons against radial and longitudinal loads applied to the cable and oppose contraction of the cable by more than 0.2%.

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 multi-fiber optical cross-coupler includes N peripheral fibers and a central fiber that are coupled together optically. The method of the invention for manufacturing such a cross-coupler consists in forming a multi-waveguide conductor by drawing a composite primary preform, the waveguides of the conductor being cylindrical elementary fibers embedded so that they are mutually parallel in mechanical and optical coupling cladding, said waveguides defining the fibers of the cross-coupler, and having opto-geometrical characteristics so that they are optically coupled over a defined length of said conductor, which length is cut off accordingly. Application to an optical coupler.

Abstract: The present invention relates to an optical fiber cable, in particular for a distribution network, and comprising an assembly of optical fibers, wherein each of the optical fibers has a mode field diameter lying in the range 7 .mu.m to 9 .mu.m at around 1550 nm, and a cutoff wavelength less than or equal to 1.35 .mu.m, and wherein the optical fibers are assembled together in the cable by being twisted around one another or around a reinforcing element, or by being disposed lengthwise.

Abstract: A support for fitting a shrinkable sleeve onto an object inside the support and the sleeve 11 mounted on it includes at least two tubular parts removed in turn from under the sleeve. It further includes means for temporarily immobilizing the last part to be removed from under the sleeve during removal of the other tubular part.

Abstract: A polymer material of the fluorine-containing polyurethane acrylate type for coating an optical fiber or for an optical fiber tape, the material being based on at least a diol, a diisocyanate, and an acrylate, and being characterized by the fact that at least one of the above compounds contains fluorine and that at least one of the above compounds contains sulfur.

Abstract: A machine for overmolding an equipment of an underwater cable includes a heated mold. The mold has a fixed half-mold with two side injection molding inlets and a mobile half-mold on a machine frame. These are coupled to a high-pressure injection molding press through an overmolding material distribution chamber and to the ends of the mold cavity. The machine finds an application in overmolding joint boxes and repeater housings.