Siemens Aktiengesellschaft

Guenter Zeidler

Ulrich Oestreich

Gerhard Lange

Helmut Saller

Franz Auracher

Hubert Aulich

Heinz Hacker

Gernot Schoeber

Nikolaos Douklias

Heinz Glaser

Dieter Schicketanz

Heinrich Liertz

Herbert Larsen

Juergen Barfuss

Ernst Ney

A stranding element for use in forming optical cables has an envelope and a plurality of bands, which are each formed of a plurality of light waveguide fibers arranged in a band stack. The band stack is received in a cavity of the envelope of the stranding element. In one embodiment, the envelope has a cross sectional cavity corresponding to the band and the envelope and band stack are longitudinally twisted substantially the same amount. In another embodiment, the band stack is received in a skin and is twisted in an envelope, which has a hollow tubular form.

Stranding element for optical cables

An optical cable comprises a plurality of light waveguides, which are combined in a group of small bands, and the group of small bands are arranged in longitudinally extending chambers of a core element. Each of the chambers in the core element can have an increasing width as the radial distance from the center of the core element increases and the bands can be arranged in sub-stacks having increases widths corresponding to the increased width of the chamber. In another embodiment, each of the bands in the stack has an increasing width in the radial direction to fill the chamber. In another embodiment, each of the chambers has a rectangular cross section, with the cross section increasing in a step-like manner due to steps formed in the partitions and the bands which are arranged in the chambers are arranged in sub-stacks to fill each portion of the chamber.

Optical cable having a plurality of light waveguides

Optical cable with at least one optical waveguide

Longitudinally water-tight cables, such as communication cables, are produced so that the interior of such cables have a filling material containing a water-repellant substance and relatively small diameter gas bubbles embedded in the filling material. The filling material is thickened with a reticulating thixotropic substance having a 3-dimensional network-like structure which is disruptable under mechanical influence and is regenerable over a time span in a motionless state with a significant increase of viscosity. The size of the gas bubbles are adjusted relative to the resistance to disruption of the network-like structure so that the buoyancy of such gas bubbles is significantly below such resistance to disruption in the motionless state of the filling material whereby such gas bubbles are maintained in their respective positions within the filling material in a time-stable manner during a motionless state.

Longitudinally water-tight cables

Longitudinally water-tight cables, such as communication cables, are produced so that the interior of such cables contain a filling material which includes a water-repelling substance and relatively small diameter gas bubbles substantially uniformly embedded therein. The filling material contains an admixture of thermoplastic rubbers or rubber-like thermoplastic materials which are molten at the processing temperature utilized in the course of cable filling and which soldify at the normal operating temperature range of a cable by linking, hooking or coupling via thermoplastic blocks having a correspondingly low melting range, that is lying just below the cable filling temperature. The gas bubbles, which are generated during cable filling, are maintained at their respective spatial positions within the filling material by a rubber-like network which forms in the filling material and the linking or joining points in such network can withstand the buoyancy forces of the gas bubbles without rupture.

Longitudinally water-tight cables and method of producing the same

An optical cable structure for use in high-voltage environments comprised of a metal-free cable core having optical elements therein and a multi-layer sheath encasing the cable core with all the hollow spaces within the cable core and in the sheath being filled with a softened or plasticized cross-linked synthetic material selected from the group consisting of a polyurethane resin, an epoxy resin and a polyester resin and at least the outer layer of the multi-layer sheath is composed of a creep-resistant material based on a compound selected from the group consisting of a polyolefin, such as a polyethylene or polypropylene, a polyurethane, a polyester or a polyester-elastomer. Such an optical communication cable structure is stabile in high-voltage environments and can be laid as desired adjacent structures carrying high voltage and can, for example, be suspended at overhead voltage lines.

High voltage stabile optical cable structures

An optical communication cable is comprised of one or more optical transmission elements loosely positioned within a double-layer synthetic material wrapping. A spun covering composed of elongated (50 to 200 mm) intertwined or unintertwined fibers at least partial coated with an adhesive is positioned about the wrapping. A relatively soft outer casing composed of a synthetic material having a modulus of elasticity smaller than 500 N/mm.sup.2 is bonded onto the spun covering via the adhesive layer. Such cable construction provides improved flexibility and mechanical stability.

Optical communication cable having a reinforced casing

An optical communication cable structure having a longitudinally gas-impermeable cable core surrounded by an inner sheath, an intermediate layer and an outer sheath with the intermediate layer being bonded to the inner and outer sheath. The intermediate layer is comprised of a simple or crossed spinning of yarn, such as an aramide yarn, which is wound about the cable core with a given length of lay approximately corresponding to the diameter of the cable core and at select spaced apart cable length intervals the yarn is wound with a substantially shortened length of web lay relative to the given length of cable lay, to define space-free pressure windings compressing the core at such select intervals. With this type of an arrangement, inflation of the inner sheath and occurrence of longitudinal gas channels extending along the length of the cable core is avoided.

Gas pressure tight optical cables

In order to be able to measure the attenuation of a lightwave guide fiber definitely and reproducibly, it is suggested to offer a mode distribution to the lightwave guide to be measured which corresponds with the 'steady state' of a very long fiber. A mode mixer and a mode stripper is for this purpose connected in series with the lightwave guide to be measured. All core modes and leakage- and jacket modes are excited in the mode mixer. In the mode stripper the jacket- and leakage modes are again stripped (absorbed) so that a mode distribution, comparable to the 'steady state', remains.

Device for measuring the attenuation of optical waves on optical

A communication cable having at least one light waveguide of a glass fiber provided with a close fitting casing characterized by the casing being prestressed in tension to exert a uniform constant longitudinal compression upon the glass fiber. The casing material, which may be a thermoplastic material selected from a group consisting of polyester, fluoropolymers, polyamides and polymethacrylates, can also be impregnated with filaments which are also placed in tension to apply a compressive force on the glass fiber.

Communication cable with glass fiber light waveguides

A light waveguide with a high tensile strength including a light conducting or optical fiber being coated with a plastic coating to improve the tensile strength characterized by the plastic coating being a plastic lacquer applied directly on the surface of the light conducting fiber, being a high temperature stable material selected from a group consisting of polyurethanes, epoxides, polyesters, polyesterimides, polyimides, and polyvinyl dimethoxymethane, which material has a softening temperature of at least 150.degree. C. The coating has a thickness of at least 2 .mu.m and is uniformly concentrically applied over the entire length of the light conducting fiber without any surface defects. The light waveguide may include an outer covering which is either tightly applied or loosely applied onto the light conducting fiber and its coating. To improve movement of the light conducting fiber and its coating in the covering, a slide layer may be interposed between the outer covering and the plastic lacquer coating.

Light waveguide with a high tensile strength

A communication cable is composed of a number of optical fibers with an outer coating, loosely twisted together to form basic groups, provided with tension-relieving wires and sheathed to form a cable while filling the interspaces with lubricants.

Communication cable

An optical transmitter, a plurality of optical receivers and light wave guides operatively interconnecting the transmitter and receivers. In one embodiment the transmitter has a light emission surface in the order of a plurality of light wave guide cross-sections and the ends of the light wave guides thereadjacent are disposed in close side-by-side relation to one another and in close proximity to the light emission surface of the transmitter. In other embodiments the transmitter has a light emission surface in the order of a single light wave guide cross-section and interposed between the light emission surface and the light wave guides is an optics system.

Growing community of inventors

Unterpfaffenhofen, Germany

Guenter Zeidler