Abstract: A depolarizer operates by splitting light traveling along an optical fiber into two sub-beams. One of the sub-beams is inserted into a recirculation loop, where it has its polarization state altered. The light in the recirculation loop is then reinserted into the fiber at a position prior to that at which the splitting occurred.

Abstract: Broadband in-line gratings in optical waveguides are disclosed. The gratings have a bandwidth of at least 2 nm (preferably at least 4 nm) and a peak reflectivity of at least 70% (preferably at least 90%). Exemplarily, such gratings can be formed in H.sub.2 -treated Si-based fibers that support a normalized index change of at least 10.sup.-3. Gratings according to the invention can be used, for instance, to form pump radiation reflectors in an optical fiber communication system with Er-doped fiber amplifiers.

Abstract: A laser generates a beam which is actively steered into an optical element having a waveguide which receives and transmits the beam. The waveguide is coupled to an optical fiber which is also actively steered. Both the beam steering and fiber steering mechanisms seek to align the beam from the laser to the fiber for maximum output. The beam steering mechanism features a pair of planar mirrors pivoted at right angles to each other. A precision force transducer will cause desired amounts of pivoting to adjust the beam. The fiber steering mechanism features a pair of flexures, arranged with bending moments of the flexures being at right angles. Electrical signals control the extent of bending in each flexure. The amount of light in the fiber is sensed downstream from both steering mechanisms and compared to an expected amount.

Abstract: Disclosed is a fiber amplifier system including a gain fiber having a single-mode core doped with active dopant ions capable of producing stimulated emission of light at wavelength .lambda..sub.s when pumped with light of wavelength .lambda..sub.p. Spliced to the gain fiber is a light-attenuating fiber having a core containing a dopant that attenuates light of wavelength .lambda..sub.p but not .lambda..sub.s. The amplifier is conventionally employed in a system including an incoming telecommunication fiber for introducing light of wavelength .lambda..sub.s into an end of the gain fiber, the amplified signal being connected to an outgoing telecommunication fiber. The system further includes a pump source for introducing light of wavelength .lambda..sub.p into an end of the gain fiber. Elements of the system can be arranged for forward pumping, counter pumping and dual ended pumping.

Abstract: A fiber cable retention mechanism for securing an optical fiber cable to an optical fiber connector includes a sleeve assembly having a longitudinal axis. The sleeve assembly has an inner passageway which is disposed along the axis and sized to receive the cable connecting end of the connector. The assembly is further sized to securely receive at least a portion of the cable between the assembly and the cable connecting end.

Abstract: A method for the alignment of an optical fiber on the optical axis of a light-emitting or light-receiving semiconductor component uses only line contacts between the metal parts. With the component being fixed to a base provided with two grooves, and the fiber being provided with a sleeve, the position of the fiber is determined in polar coordinates by at least two plates which lie in grooves and form angles that are adjustable. The positions are fixed by laser soldering when the alignment is obtained. The device can be applied to optical heads.

Abstract: Improved image guides for use in endoscopes, borescopes and analogous optical viewing scopes and a method for the manufacture of such image guides. An image guide is manufactured by drawing a three-glass fiber to a minimal diameter. Plural fibers are then gathered in a bundle and heated to fuse an outer fusible cladding on adjacent fibers. The bundle then can be cut to length and the ends are polished to produce an image guide. The resulting image guide has a spatial resolution that approximates the spatial resolution from conventional optics, is rugged and simpler to manufacture than other image guides.

Abstract: An optical waveguide (11) is composed substantially entirely of triazine.

Abstract: A cable termination member (10) having improved strain relief features for isolating optical fiber members (21,22) in a terminated optical fiber cable (20) from external stresses.

Abstract: An optical surface mounting circuit is provided which does not necessitate alignment of optical axes of optical parts used therein, reduces greatly the number of production steps, enables mass-production of complicated optical circuits, and facilitates designing of optical circuits and changes in the designing. The optical surface mount circuit includes a substrate having optical wave guides and a first guide means positioned and fixed relative to an end surface of the optical wave guide, and an optical part having an optical terminal and a second guide means at the bottom positioned and fixed relative to the optical terminal. The first and the second guide means are engaged and fixed on the front surface of the substrate, and the optical terminal and the end surface of the optical wave guide are optically connected.

Abstract: An optic intensity modulator includes a substrate of an optic material that is conductive to light and acoustic waves and has both electrooptic and piezoelectric properties. A pair of associated elongated light waveguides is formed in the substrate, with the waveguides extending substantially coextensively with one another, and being separated from one another by a transverse distance that gradually varies along the courses of the waveguides. Each of two portions of light of substantially identical properties is launched into one of the waveguides for propagation longitudinally thereof, and different phase shifts are induced in the light portions as they propagate in the waveguides by imposing different variable electric fields onto each of the waveguides. The light portions are combined with one another subsequently to their emergence from the waveguides with attendant amplitude modulation of the combined output light due to interference between such phase-shifted light portions.

Abstract: Disclosed is a cable in which one tube holding light waveguides is connected by a plastic web to another tube holding metallic current carrying conductors. When buried in the earth, the cable may be located by means of a magnetic field produced by the current carrying conductors, but the cable retains the advantage of the tube carrying the light waveguides being dielectric.

Abstract: The invention relates to an optical plug connector comprising two plugs (1,2) each of which holds an end portion of an optical waveguide (OWG 10) and which can be inserted from opposite sides into a coupling sleeve (7) until the end faces of the OWGs (10) are located against each other, and comprising a guide element (5,9) for guiding and aligning the OWGs (10), which guide element can be axially inserted in both plugs (1,2) and which extends beyond their joint area. Damage to the OWGs caused by an inappropriate attempt to form a plug connection without using a guide element is precluded in that stop elements (17,18) are provided at the plugs, which stop elements cooperate with the stop elements of the mating plug in such a manner that when the guide element (9) is not inserted, the OWG-holding elements (12) of the plugs are prevented from moving completely towards each other in an axial direction.

Abstract: A conduit for receiving lengths of fiber optical cable, which enhances light emission and transmission within the cable by substantially reducing an air gap located between a polymeric core and an outer cladding of the fiber optical cable. The conduit of the present invention has a retaining member that defines a first channel adapted to receive the fiber optical cable and a base member that defines a second channel adapted to receive the cable. The retaining member is mounted with the base member, such that the cable is retained within the first and the second channels and a compressive force is exerted on the cable, which substantially eliminates the gap between the core and outer cladding. Furthermore, the conduit of the present invention supports and guides the cable and facilitates the installation thereof.

Abstract: A waferboard assembly incorporates mechanical registration features into a substrate platform to facilitate the passive alignment of lasers integrated on a chip to fibers in integral contact with the substrate. The waferboard includes two front pedestal structures and one side pedestal structure, and two vertical post structures within a mounting region defined by the pedestal structures. The laser chip is mounted on the vertical post structures, and placed in concurrent abutting contact with the pedestal structures. The waferboard is fabricated by etching the substrate to form the front and side pedestal structures, and etching the substrate to define the grooves. In order to form the post structures, a polyimide material is deposited on the substrate using an appropriate mask.

Abstract: A fiber optic cable entry connector is described that facilitates integration of fiber optic cables with trunk housings of the type utilized in the CATV industry. The entry connector provides EMI/RFI shielding and weather sealing and is readily compatible with existing fiber optic cables. The entry connector may be reused and may be cycled open and closed to facilitate access to the cable. The entry connector includes a clamp assembly and an entry body that are configured to be mated in combination. The clamp assembly is configured to secure the cable within the connector and to provide weather sealing between the connector and the cable. The clamp assembly is configured to preposition the cores of the cable for insertion through the entry body and into the trunk enclosure. The clamp assembly may be readily adapted to accommodate any sized existing fiber optic cable.

Abstract: An optical fiber payout canister (36) comprises a bobbin (42) upon which an optical fiber (34) is wound. A shroud (50) overlies the bobbin (42), and a layer (54) of an ablative material is coated onto at least a portion of the inside wall (48) of the shroud (50) adjacent to the bobbin (42), so that the optical fiber (34) may contact the ablative material (54) during payout. Desirably, the ablative material (54) has a hardness equal to or less than that of the buffer layer of the optical fiber (34). In one embodiment, the ablative material (54) has a composition similar to that of the polymer buffer layer, such as an urethane acrylate. The ablative material (54) removes energy from the optical fiber during payout, and in particular reduces the circumferential component of the energy, permitting the optical fiber (34) to be dispensed through a dispensing opening (58) in an end wall (60) of the shroud (50).

Abstract: A 2-input/2-output directional coupler is arranged as an element coupler/splitter for a first stage, and 1-input/2-output coupler/splitters are used as element coupler/splitters for a second stage and subsequent stages. Output ports of these element coupler/splitters are concatenated with input ports of other element coupler/splitters to form a 2-input/multi-output coupler/splitter. An optical signal can be inputted through one input port of the first-stage 2-input/2-output directional coupler, and an optical signal for optical line monitoring can be inputted through the other input port. It is unnecessary, therefore, to use an optical wavelength division multiplexer/demultiplexer or other optical part which conventionally is connected at the time of optical line monitoring.

Abstract: A coil of optical fiber can be self-supporting by bearing a layer of brittle thermoplastic adhesive that adheres adjacent convolutions of the fiber together. Because it is self-supporting, the coil needs no hub so that either end of the fiber can be unwound. Preferred thermoplastic adhesives are marketed in the optical industry as blocking waxes.

Abstract: A needle type lens structure comprises, an inner tube having a relay lens inserted therein, an outer tube mounted around an outer periphery of the inner tube in concentric relation thereto with a predetermined gap, and light transmitting device, for guiding illumination light to the distal end of the needle type lens, provided axially between the inner tube and the outer tube.