Abstract:
Dispositifs optiques possedant une ou plusieurs fibres optiques supportees rigidement et procede de fabrication, dans lequel une ou plusieurs fibres optiques (20, 26, 68, 78) sont interfacees avec un materiau rigide de support (24, 30, 72, 74) au moyen d'une restructuration moleculaire des surfaces specifiques d'interface des fibres et du materiau de support. La fibre optique supportee rigidement peut etre obtenue par l'assemblage d'une partie de surface exterieure longitudinale de la fibre (20, 26, 68, 78) en juxtaposition avec un materiau de support rigide (24, 30, 72, 74) possedant un point de fusion inferieur a celui de la fibre. Cet assemblage peut etre chauffe pour permettre le ramollissement partiel du materiau de support (24, 30, 72, 74) le long de la surface exterieure de la fibre (20, 26, 68, 78) pour permettre la fusion des deux surfaces. L'assemblage peut ensuite etre refroidi en dessous du point de fusion du materiau de support 24, 30, 72, 74) pour produire un assemblage de fibres optiques de construction renforcee comprenant une fibre optique fondue sur un materiau rigide de support. Plusieurs dispositifs optiques peuvent etre formes en combinant ces fibres optiques supportees rigidement.
Abstract:
A process and apparatus for fabricating an optical fiber communication cable are described herein. In a first aspect of the present invention, smooth operation of a die (18, 20) for forming a metal containment tube (30) for housing at least one optical fiber (14) is promoted by first passing a metal strip (12) through a shaving die (28) to remove any shearing burrs along the strip edges and to maintain the width ofthe strip (12) within a desired tolerance. In a second aspect of the present invention, various approaches for effectively sealing the containment tube (30) are described.
Abstract:
An electric conductor suitable for use in an overhead electrical and optical transmission system comprises a layer or layers 35 of helically wound wires, at least one elongate compartment 36 within and extending throughout the length of the conductor and, loosely housed in the elongate compartment, at least one optical fibre ribbon structure 37 comprising a plurality of optical fibres 1 and flexible elongate reinforcing elements 2 of resilient material arranged side by side and embedded in an elongate body 3 of plastics material, each resilient reinforcing element being set in such a form that the ribbon structure follows a path of smoothly curved undulations whose axes of curvature lie parallel to one another and normal to the longitudinal axis of the ribbon structure. If, when the conductor is installed or in service, the undulating ribbon structure 37 is subjected to a tensile force, the ribbon structure will straighten in a lengthwise direction against the action of the undulating resilient reinforcing elements 2 thereby reducing the tensile force otherwise applied to the optical fibres 1 and, when the tensile force is removed, the ribbon structure will return towards its original undulating form.
Abstract:
An optical communication element assembled from an optical fibre bonded in a state of axial compressive stress to a metal tape. The tape may be folded-up into a tube and sealed by soldering. Such elements are strong and not sensitive to stress corrosion.
Abstract:
An optical telecommunication element which is constructed from a central optical fibre which is under an axial pressure and which is incorporated in a close-fitting sheath of supporting fibres having a modulus of elasticity which is at least 4000 kg/mm 2 and is fixed within the sheath by a layer of cured lacquer.
Abstract:
A glass layer (2); is formed inside a silica glass tube (3) and another glass layer (1) having a refractive index higher than that of the abovementioned glass layer (2) is formed on said glass layer (2). After these glass layers (1,2) are formed, one end of the glass tube (3) is collapsed. While the internal pressure of the glass tube is being reduced below the atmospheric pressure, the glass tube is caused to collapse by heating, thereby yielding a preform for an optical fiber. The optical fiber produced from this preform has the difference in the refractive indices of the two orthogonal major axes (x, y) of at least 1.6 x 10 -4 and maintains the linear polarization plane.