Abstract: A storable tubular element for covering an electric cable joint which includes a rigid tubular support with a three layer sleeve having an unstretched bore of a size less than the external diameter of the support mounted on the tubular support in radially stretched condition. The element is usable for a group of cables having several different diameters and the properties and thicknesses of the layers are selected so that with storage on the support, the layers do not tear and so that when the sleeve is applied to a joint, the sleeve will apply the desired pressure to the cable even though it has a temporary residual deformation and does not immediately tend to return to its initial unstretched state.

Abstract: A storable covering element for electric cable joints which includes a tubular support on which a multi-layer sleeve is mounted in radially stretched condition, a cable joint with such a sleeve and a sleeve for such use. The sleeve has an inner layer of cross-linked polymeric material which has a temporary residual deformation after storage for at least 24 months at room temperature which is less than such deformation of the layers outwardly thereof and preferably has a modulus of elasticity greater than the modulus of elasticity of the layers outwardly thereof. The outer layers are also made of cross-linked polymeric material, and each layer is bonded to the adjacent layer so that the inner layer will pull the outer layers radially inwardly when the sleeve is applied to a cable joint.

Abstract: Connectors for optical cables in ribbon form and a process for making such connectors in which metal plates for the enclosing the cable ends are made by cold, plastic flow forming of grooves in the plates with a punch having ridges produced by a process which produces grooves which hold the positions of the optical fibers between the plates within narrow tolerances. In the process, a punch body with partially formed ridges is mounted on a head rotatable about the axis of the body and movable toward a grinding wheel which is movable in a path perpendicular to the direction of movement of the head toward the grinding wheel. After two opposite passes of the grinding wheel along the side of a ridge, the punch body is rotated 180 degrees, and the side of a corresponding ridge on the opposite side of the punch body axis is ground. The process is repeated with movement of the head toward the grinding wheel, which is measured, until the sides of all ridges are ground.

Abstract: An optical, low-noise amplifier of the active-fiber type, which fiber contains a laser light emitting substance, adapted to be connected to an optical telecommunication fiber and receiving light therefrom at the transmission wavelength. The active fiber is also fed from a light source at a pumping wavelength and has a length corresponding to a partial absorption of the pumping light. Downstream of active fiber, there is a selective mirror device which reflects the light at the pumping wavelength and is transparent to the transmission wavelength light. Preferably, the mirror device consists of an optical demultiplexer adapted to separate the transmission wavelength and the pumping wavelength on two output fibers. A mirror which reflects the pumping wavelength is present at the end of the fiber carrying the pumping wavelength.

Abstract: An optical amplifier (3) in accordance with the invention consists of the assembly of a length of active-core optical fiber (8), single-mode to both pumping and signal optical radiations, and a dichroic coupler (6) which includes two optical fiber lengths (9, 10), both single-mode to pumping and signal optical radiations, coupled to each other over one portion (11) by fusion of the respective claddings and substantial setting in common of the respective cores in the fused portion (11).

Abstract: A method of manufacturing a body with a surface of revolution at one end co-axial with an axis of the body in which the body is mounted on a rotatable shaft with the body axis coaxial with the shaft axis, such shaft being movable by a limited amount transversely to its axis, the shaft with the body thereon is rotated and any transverse movement of the body relative to its axis is measured as material is removed from the end of body to form the surface. Mechanical compensating forces determined by the transverse movement measurements are applied to the shaft to substantially prevent such transverse movement.

Abstract: A pair of interengageable connectors for interconnecting optical fiber tape or ribbon cables which have a plurality of parallel optical fibers within a relatively thin and wide covering. Each connector has a ferrule formed by semicylindrical elements with engaging and axially extending planar faces. One end of the elements is a coupling face, and the planar faces have grooves extending axially from the coupling face for receiving the fibers with the covering removed and a recess remote from the coupling face for receiving the fibers with the covering thereon. The elements are held together by a sleeve which extends from at or adjacent the coupling face toward the other end of the ferrule. A ring nut with teeth for engaging corresponding teeth of the other connector encircles the sleeve and the ferrule and is slidable axially with respect thereto. A spring urges the ring nut toward the end of the ferrule remote from the coupling face.

Abstract: The invention relates to an optical amplifier, in particular for optical fiber telecommunication lines (1), operating with a transmission signal in a predetermined wavelength range, which amplifier comprises a fluorescent active optical fiber (6) doped with erbium, having two cores (11 and 12, 101 and 102), one (11, 101) of which is connected to a fiber (4) in which a transmission signal to be amplified and a luminous pumping energy are multiplexed, and to an outgoing fiber adapted to transmit the amplified signal, whereas the second core (12, 102) is optically coupled to the first core and is capable of absorbing the spontaneous erbium emission which would constitute a noise source, allowing a signal to be amplified in a wavelength range substantially corresponding to the tolerance range of the commercially available signal laser emitters.

Abstract: A stretched, elastic sleeve for enclosing a joint between a pair of interconnected electric cables, or an end of such a cable, is mounted on a tubular supporting body formed by a helically wound tape with contiguous turns. The tape has transversely extending notches to improve the bendability of the tape. After the assembly of the sleeve and the body is disposed around the joint or cable end, the tape is pulled out of the sleeve permitting the sleeve to contract and engage the cable.

Abstract: An optical fiber telecommunication line composed of a number of series connected optical cables arranged end-to-end includes an active core optical fiber amplifier for the transmitted signals between each adjacent pair of optical cables. Two pumping optical radiation sources are connected to each active core optical fiber within each of the amplifiers, one source for each end of a single active core optical fiber. One of these two sources is placed into service and the second one is kept in reserve to be placed into service if the first one fails. A microprocessing circuit causes the sources to send distinctive recognizable alarm signals indicative of the state of an associated amplifier to terminal stations at the ends of the line and to receive therefrom control signals to control and exchange the functions between the two sources as necessary.

Abstract: Process and apparatus for inserting a rigid support in a contractible sleeve used to enclose a joint between a pair of electric cables. The support has an outer diameter greater than the unstretched inner diameter of the sleeve. The sleeve is enclosed in a pair of separable half-shells having radially movable pressure elements extending radially inwardly therefrom and engageable with the outer surface of the sleeve. The pressure elements are urged inwardly by compression springs, and the pressure applied to the sleeve by the pressure elements increases with radially outward movmeent thereof. One end of the support is inserted in one end of the sleeve and the support is pulled axially into the sleeve while axial movement and shortening and buckling of the sleeve is opposed by the pressure elements.

Abstract: An apparatus for manufacturing a body provided at one end with a surface of revolution. The axis of the apparatus is aligned with a predetermined longitudinal axis of the body. The apparatus including a mechanism for the compensation of the oscillations of the free end of the body. The apparatus is disposed around an assembly comprising a mandrel at the end of a flexible rotatable shaft, the mechanism including a bearing surrounding a component of the assembly. A plurality of means generating oscillating mechanical forces against the bearing means are guided by signals derived from rotation of the shaft to provide phase and amplitude synchronization and compensation of the oscillations of the free end of the body.

Abstract: An interconnect system for ribbon-joined optical fibers includes two connectors (1, 2) integrally attached to the ends of respective optical fiber ribbons (3, 4), in which each connector (1, 2) consists of a pair of coupled metal plates (5) rigidly fastened to each other, between which two or more optical fibers (7) belonging to a ribbon (3, 4) made of parallel optical fibers as well as alignment plugs (10) are clamped. At least a plate (5) in each connector (1, 2) includes an element made of metallic material in which several housing grooves (6, 9) for the optical fibers (7) of the ribbon (3, 4) and for the alignment plugs (10) are formed by cold plastic deformation using the same punch for all the plates belonging to one series.

Abstract: An optical position sensor for indicating the position of a movable body with respect to a reference point. A first optical signal at one wavelength and a second optical signal at a different wavelength, both modulated at a radio frequency, are transmitted through an optical fiber to the reference point at which a semi-reflecting mirror which passes the first signal and reflects the second signal is disposed. The first signal is reflected by the body into the optical fiber, and a phase comparator coupled to the fiber compares the phases of the modulating signals on the reflected first signal and the reflected second signal to determine the position of the body relative to the mirror.

Abstract: A paper-polymeric material, laminated tape, an electric cable insulated with such tape and a method of making the tape. The tape includes a film of polymeric material to at least one surface of which a paper tape comprising cellulose fibers is bonded by contacting the paper tape at room temperature with the film heated to a temperature above its melting temperature. Prior to contacting the paper tape with the heated film, fibrils are caused to project from at least one surface of the paper tape by subjecting it to a high voltage, electrostatic field. In the laminated tape, the fibrils are embedded in the material of the film to provide an improved bond between the film and the paper tape.

Abstract: A method and apparatus for determining the position of a mobile body which is movable along a rectilinear path relative to a fixed reference body in which the position of the mobile body is independent of any spurious movements of the body or variations in the intensity of the source of radiation.

Abstract: Apparatus for applying an elastic sleeve to a joint between a pair of electric cables including a tubular cylindrical plastic support with an internal bore larger than the diameters of the cables and on which the elastic sleeve in its stretched state is mounted. A pair of openable mobile elements surround the support, and the element farther from an end of the sleeve is releasably secured to the support, such as by pins extending from the element through openings in the support and engageable with the outer surface of one of the cables. The other element is slidable on the support and can be moved toward the end of the sleeve. A screw mechanism acting between the elements moves them away from each other causing the support to be pulled out of the sleeve. With the apparatus positioned with the support and sleeve around the joint, the removal of the support permits the sleeve to contract around the joint.

Abstract: An optical fiber cable with a plastic core having longitudinally extending plastic tubes embedded therein, each plastic tube loosely containing at least one optical fiber. The materials of the core and the tubes are selected so that there is no significant bond or link between the outer surfaces of the tubes and the core to permit easy separation of the tubes from the core. Alternatively, there may be layers of a fluid or powder intermediate the outer surfaces of the tubes and the core so that, if desired, the tubes and the core can be made of the same plastic material although, even with this structure, the tubes may be made of a plastic material different from the plastic material of the core.

Abstract: In mobile laying apparatus for laying an elongated element, such as a cable, in a trench, especially a trench in a sea bed, which apparatus is advanced in a predetermined direction and includes apparatus for digging the trench and ways along which the element slides as it is deposited in the trench, tension control apparatus and a method for preventing the accumulation of such element upstream of the laying apparatus as the element is laid. In the method, a tension force is applied to the element so that the tension thereon upstream of the laying apparatus is at least equal to the tension on the element downstream of the laying apparatus. The tension control apparatus includes motor driven rollers or tracks at the ways which engage the element. The torque which the driving motors apply or alternatively, the energization of the driving motors and the advance of the laying apparatus is controlled by the position of a portion of the element upstream of the laying apparatus.

Abstract: An optical fiber cable with an elongated core of transparent plastic material having a plurality of readily visible tubes of a dull material embedded therein and extending longitudinally thereof. Each tube loosely receives at least one optical fiber. The core has a plurality of grooves at the outer surface thereof which extend parallel to the paths of the tubes and which are spaced from the tubes, and the grooves have a hydrogen retaining material therein. Each groove is on a radial line intermediate pairs of tubes.