Abstract: An optical fibre assembly comprises a hollow core optical waveguide comprising a hollow core surrounded by a structured arrangement of longitudinally extending capillaries providing an inner cladding surrounded by an outer cladding; a diagnostic solid core optical waveguide comprising a solid core surrounded by a cladding, and extending substantially parallel to the hollow core optical waveguide; and a jacket surrounding both the hollow core optical waveguide and the solid core optical waveguide and forming a common mechanical environment for the hollow core optical waveguide and the solid core optical waveguide. The optical fibre assembly may be or may comprise or be included in an optical fibre cable, and may be used in a method for testing hollow core optical waveguides.

Abstract: An optical fibre assembly comprises a hollow core optical waveguide comprising a hollow core surrounded by a structured arrangement of longitudinally extending capillaries providing an inner cladding surrounded by an outer cladding; a diagnostic solid core optical waveguide comprising a solid core surrounded by a cladding, and extending substantially parallel to the hollow core optical waveguide; and a jacket surrounding both the hollow core optical waveguide and the solid core optical waveguide and forming a common mechanical environment for the hollow core optical waveguide and the solid core optical waveguide. The optical fibre assembly may be or may comprise or be included in an optical fibre cable, and may be used in a method for testing hollow core optical waveguides.

Abstract: An armoured power cable (10) comprises a cable core (11) and an armour layer (21) comprising a plurality of armouring wires (22) laid around the cable core (11), wherein at least 10% of the armouring wires (22) are wavy wires (23) having a zig-zag shape laying on the outer surface of the cable core (11).

Abstract: It is disclosed a process and an apparatus for manufacturing a figure of eight cable. An extrusion head has separate extrusion dies extruding in parallel a first and second outer sheath around a first and second core, respectively, so as to provide two separate cable elements having respective longitudinal axes laying in a first plane. While the outer sheaths are in a softened state, the cable elements are passed in parallel through a twisting die which causes their longitudinal axes to lay in a second plane forming a predetermined twisting angle with respect to the first plane. This twisting causes the outer sheaths to join together, thereby forming a figure of eight cable.

Abstract: An optical fibre assembly comprises a hollow core optical waveguide comprising a hollow core surrounded by a structured arrangement of longitudinally extending capillaries providing an inner cladding surrounded by an outer cladding; a diagnostic solid core optical waveguide comprising a solid core surrounded by a cladding, and extending substantially parallel to the hollow core optical waveguide; and a jacket surrounding both the hollow core optical waveguide and the solid core optical waveguide and forming a common mechanical environment for the hollow core optical waveguide and the solid core optical waveguide. The optical fibre assembly may be or may comprise or be included in an optical fibre cable, and may be used in a method for testing hollow core optical waveguides.

Abstract: In one embodiment, an optical cable, which is a flat drop cable, includes a cavity shaped in the form of a stadium in a sectional view of the optical cable. The cable further includes an outer sheath enclosing the cavity, a first strength member, and a first optical fiber element disposed in the cavity. The first optical fiber element includes an optical fiber and has an oscillating pattern within the cavity on an oscillation plane parallel to a longitudinal plane of the cable. The height of the cavity in the sectional view substantially corresponds to a height of the first optical fiber element.

Abstract: It is disclosed a figure of eight cable comprising a first cable element comprising a first core enclosed by a first outer sheath, a second cable element comprising a second core enclosed by a second outer sheath and a web joining the first and second outer sheaths so as to provide the cable with a major plane of symmetry X which comprises the longitudinal axes of the first and second cable elements. The cable also comprises at least one strength member embedded within the first or second outer sheath. All the strength members of the cable are substantially located on the major plane of symmetry X of the cable.

Abstract: An optical cable comprises a group of optical modules. Each of the optical modules comprises a strength member, a plurality of optical fibers arranged about the strength member, the plurality of optical fibers being arranged substantially on a circumference concentric with the strength member, and a retaining element arranged about the plurality of optical fibers. The strength member is covered by a coating, and the plurality of optical fibers are at least partly embedded within the coating. The optical cable comprises an outer sheath around the group of optical modules. The optical cable does not have a central strength member.

Abstract: An armoured power cable (10) comprises a cable core (11) and an armour layer (21) comprising a plurality of armouring wires (22) laid around the cable core (11), wherein at least 10% of the armouring wires (22) are wavy wires (23) having a zig-zag shape laying on the outer surface of the cable core (11).

Abstract: An optical cable comprising an optical core and an external sheath surrounding the optical core, wherein the external sheath comprises an inner layer circumferentially enclosing the optical core and an outer layer circumferentially enclosing the inner layer and comprising at least one longitudinal cavity accessible from outside the external sheath and extending through at least a portion of the outer layer thickness. The inner and outer layers of the external sheath are made of a first material having a first tensile strength, while the cavities in the outer layer are filled with a second material having a second tensile strength lower than the first tensile strength.

Abstract: In one embodiment, an air-blown optical fiber unit includes one or more optical fibers, an inner layer substantially completely embedding the one or more optical fibers, and an outer layer radially external to the inner layer. The inner layer has a tensile strength of from 0.1 MPa to 1 MPa, and an elongation at break of from 10% to 80%.

Abstract: In one embodiment, an air-blown optical fiber unit includes one or more optical fibers, an inner layer substantially completely embedding the one or more optical fibers, and an outer layer radially external to the inner layer. The inner layer has a tensile strength of from 0.1 MPa to 1 MPa, and an elongation at break of from 10% to 80%.

Abstract: In one embodiment, an optical cable, which is a flat drop cable, includes a cavity shaped in the form of a stadium in a sectional view of the optical cable. The cable further includes an outer sheath enclosing the cavity, a first strength member, and a first optical fiber element disposed in the cavity. The first optical fiber element includes an optical fiber and has an oscillating pattern within the cavity on an oscillation plane parallel to a longitudinal plane of the cable. The height of the cavity in the sectional view substantially corresponds to a height of the first optical fiber element.

Abstract: An optical cable comprises a group of optical modules. Each of the optical modules comprises a strength member, a plurality of optical fibers arranged about the strength member, the plurality of optical fibers being arranged substantially on a circumference concentric with the strength member, and a retaining element arranged about the plurality of optical fibers. The strength member is covered by a coating, and the plurality of optical fibers are at least partly embedded within the coating. The optical cable comprises an outer sheath around the group of optical modules. The optical cable does not have a central strength member.

Abstract: An optical cable comprising an optical core and an external sheath surrounding the optical core, wherein the external sheath comprises an inner layer circumferentially enclosing the optical core and an outer layer circumferentially enclosing the inner layer and comprising at least one longitudinal cavity accessible from outside the external sheath and extending through at least a portion of the outer layer thickness. The inner and outer layers of the external sheath are made of a first material having a first tensile strength, while the cavities in the outer layer are filled with a second material having a second tensile strength lower than the first tensile strength.

Abstract: An optical cable includes an optical module which includes a strength member, a plurality of optical fibers arranged about the strength member, the optical fibers being arranged substantially on a circumference concentric with the strength member, and a retaining element arranged about the plurality of optical fibers.

Abstract: A process for manufacturing an optical fibre unit for air-blown installations includes: providing a deposition chamber for applying particulate material, the deposition chamber having an inlet end and an outlet end and a longitudinal axis; passing through the deposition chamber an optical fibre assembly including at least one optical fibre embedded in an inner layer of cured resin material, and having an outer layer around the inner layer, the outer layer including uncured resin material; injecting a flow of fluid and particle material in the chamber in a direction substantially parallel to the chamber longitudinal axis, at an injection speed of 5 m/s at most; perturbing the flow when in the chamber, thus causing the particle material to impact and partially embed into the outer layer of the optical fibre assembly; and curing the outer layer.

Abstract: An optical cable includes an optical module which includes first optical fibers and a first retaining element arranged about the first optical fibers. The module also includes second optical fibers arranged about the first retaining element, the second optical fibers being arranged on at least one circumference concentric with the first retaining element. The module also includes a second retaining element arranged about the second optical fibers, which is also substantially coaxial with the first retaining element. This optical module with coaxial retaining elements and fibers has a particularly high fiber density, while preserving the possibility to uniquely identify all the fibers.

Abstract: It is disclosed a figure of eight cable comprising a first cable element comprising a first core enclosed by a first outer sheath, a second cable element comprising a second core enclosed by a second outer sheath and a web joining the first and second outer sheaths so as to provide the cable with a major plane of symmetry X which comprises the longitudinal axes of the first and second cable elements. The cable also comprises at least one strength member embedded within the first or second outer sheath. All the strength members of the cable are substantially located on the major plane of symmetry X of the cable.

Abstract: It is disclosed a process and an apparatus for manufacturing a figure of eight cable. An extrusion head has separate extrusion dies extruding in parallel a first and second outer sheath around a first and second core, respectively, so as to provide two separate cable elements having respective longitudinal axes laying in a first plane. While the outer sheaths are in a softened state, the cable elements are passed in parallel through a twisting die which causes their longitudinal axes to lay in a second plane forming a predetermined twisting angle with respect to the first plane. This twisting causes the outer sheaths to join together, thereby forming a figure of eight cable.