Abstract: The orientation of the rotating direction of an optical fiber in an optical fiber array takes the positional axial displacement into consideration. In a method of aligning the orientation of optical fibers, or the axial displacement in an optical fiber array having a plurality of optical fibers, and an optical fiber holding member, an enlarged image of the optical fiber is obtained for each of the optical fibers using an image pick-up means. Then, a distribution of the characterized image corresponding to the positions in the radial direction of the image of the optical fiber are obtained from the enlarged image. From the distribution of the characterized image, the orientation of the rotational direction to the center of the optical fiber, or the positional axial displacement of the core center, is measured.

Abstract: In the case of fixing an optical fiber array to a substrate, wherein the optical fiber includes a V-groove substrate having at least one V-groove used for arranging an optical fiber, a fix substrate for fixing the optical fiber in the V-groove, and a pair of guide grooves arranged at both ends of the V-groove through which a guide pin used for a connection is arranged, the guide pin is arranged in the guide groove and the optical fiber array is fixed to the substrate under such a condition that one point of the guide pin is brought into contact with the substrate.

Abstract: In splicing two optical fibers in the common way, the end surfaces of the fibers are placed opposite each other and then the fiber ends are melt-fusioned using an electric arc generated between two electrodes. In order to obtain a predetermined lateral displacement of the outer surfaces of the fibers, the fiber ends are placed in positions with a displacement exceeding the desired displacement before the fusion melting. During fusion welding, an electric current of a large intensity is passed between the electrodes, and the first-set lateral displacement will decrease due to surface tension. After the fusion melting, the electric arc is continued at a reduced intensity which also produces a lower temperature in the region at the splice of the fiber ends. At this stage, the outer surfaces of the fiber ends are observed, which then become more and more aligned with each other (that is, the lateral displacement decreases) due to the surface tension.

Abstract: The disclosed method of fusion splicing silica-based optical fiber comprises removing of the polymer coating from the end portions of the respective fibers by contacting the end portions with a chemical polymer remover (e.q., hot sulfuric acid with 5% nitric acid) such that a film of material that comprises the remover remains on the stripped fiber. Typically this is accomplished by refraining from the conventional rinsing of the stripped fiber portions. The film-covered stripped fibers are then fusion spliced in conventional fashion. Splices of strength close to the strength of as-drawn fiber were obtained by this method.

Abstract: A method of coupling optical parts including bonding the optical coupling faces of two optical waveguides by butting and fusing them. Also, a method for forming a refractive-index distribution having the focusing lens effect by setting the interval between the optical coupling faces of two optical parts to 0.1 mm or more, feeding a refractive-index imaging material also serving as an adhesive into the gap between the faces, and applying light to the refractive-index imaging material from the optical coupling face of at least one of the optical parts.

Abstract: This invention relates to micro-driving members for performing alignment of optical fibers and the like. Backlash is eliminated by forming constituent elements as integral components, thereby improving driving precision. Each micro-driving member includes a base portion in which an insertion hole for an urging means is formed, a support portion integral with the base portion and opposing the insertion hole, an urged portion urged by the urging means, and a table portion for supporting a driving target. The table portion has one side connected to a first horizontal flexible portion extending from the support portion, and the other side which is open.

Abstract: Apparatus and method of providing a fiber optic signal splitter for receiving an incoming fiber optic signal and for splitting the signal into a first plurality of signals, fiber optic splicing apparatus for splicing the first plurality of fiber optic signals to fiber optic splitter apparatus which splits the first plurality of signals into a second plurality of signals greater in number than the first plurality of signals. Combination fiber optic splice tray for splicing an incoming optical fiber to apparatus for splitting optical fiber signals received over the incoming optical fiber.

Abstract: A mid-span branching method for an optical path including a multi-fiber optical cable which is constituted by a multi-fiber ribbon with a plurality of optical fibers arranged in a plane and integrated with a common coating, includes the first step of exposing an intermediate portion of the multi-fiber ribbon from the multi-fiber optical cable (step 101), the second step of extracting the exposed multi-fiber ribbon (step 102), the step of separating at least one single-core optical fiber from the extracted multi-fiber ribbon (step 103), and the step of connecting the single-core optical fiber separated from the multi-fiber optical cable to a single-core optical fiber branched from a branch cable (steps 104, 105).

Abstract: There is disclosed a coupling structure of optical fibers and optical waveguides, comprising optical fibers; an optical fiber arranging connector having a first and second members, the optical fibers being sandwiched by the first and second members to be fixed in the optical fiber arranging connector; a waveguide device having a waveguide substrate, optical waveguides being formed on a surface of the waveguide device, ends of the waveguides and ends of being aligned with each other by abutting end faces thereof against each other; an adhesive interposed and set between said end faces, the adhesive being a photo-setting adhesive, the first member being made of a material preventing light having a wavelength capable of setting said adhesive from passing therethrough, and in at least part of a region where the end faces of the optical fiber arranging connector and the waveguide device oppose to each other, at least one of the optical fiber arranging connector and the waveguide device in the vicinity of the end f

Abstract: The present invention concerns a method for aligning fiber optics. The device used to implement the method comprises an inclined support (16) for a fiber optic (15) to be aligned with one or more fibers (11) in a flat ribbon (10), and an inclined contact element (12) supporting a gripping means (9) attached to the flat ribbon. The fiber extremities engage in V-shaped guide grooves (13) having a central alignment zone (14). Alignment occurs when the fiber to be aligned and the fibers in the flat ribbon are placed in the alignment zone by sliding each of them in one of the V-shaped grooves and inwardly curving a predetermined length thereof so that the fiber extremities are placed in immediate proximity to one another and are essentially tangential to said V-shaped groove only in the area of their extremities.

Abstract: We have discovered that the strength of arc fusion splices in optical fiber can be adversely affected by particles (e.g., SiO.sub.2 particles) from the electrodes. Disclosed is a method of arc fusion splicing that can substantially increase the probability that a given fiber splice will meet a given strength requirement. The method comprises initiating the arc in a "cleaning" position selected such that the probability of incidence on the fibers of particles from the electrodes is relatively low, followed by changing the relative position between the electrodes with the arc therebetween and the fibers to the conventional "heating" position and forming the splice.

Abstract: Optical fibers typically used for data signal transmission are connected to each other in an orientation which provides self-aligning of the fiber ends. An alignment cavity is used to accept two optical fibers and guide them to a precise position with accurate alignment of the cores of the fibers. A housing unit may be employed to secure the optically aligned, joined fibers in an isolated, fixed orientation. The alignment cavity can be re-positioned automatically by the fibers entering to assure a preferred optimum alignment of the fiber ends in a vee groove internal configuration. Retaining elements are crimped to secure the fiber ends in the preferred orientation. The retaining elements may have an opening through which the optical fibers, bare or buffered may pass. Retaining elements may also capture the strength members of the optical fiber cables.

Abstract: An apparatus for adjusting the alignment of the optical fibers at a high precision, formed by a base frame having a plurality of pairs of V-grooves for mounting the optical fibers at mutually facing sides of the base frame, each V-groove being defined by a fixed member and a movable member, each movable member being movable within a guide groove defined between each adjacent fixed members, and one of each pair of V-grooves on one of the mutually facing sides has the fixed member and the movable member facing against the movable member and the fixed member, respectively, of another one of each pair of V-grooves on another one of the mutually facing sides; and a plurality of piezoelectric elements, each of which is connected with each movable member of each V-groove, for causing each movable member to move within the guide groove such that a displacement of each movable member makes an adjustment of a position of an optical fiber mounted on each V-groove.

Abstract: A method of preparing a subassembly for connecting an integrated optical device (21) to an optical cable:a multiferrule is used having internal passages (2) opening onto its opposite first and second faces (6, 7),an intermediate optical cable is used,the intermediate fibers (27) are inserted into the passages (2) through the first face (6),the fibers (27) are fixed in the passages (2) over part of their length,the multiferrule and the fixed fibers (27) are cut to obtain a multiferrule section (34) in which the fibers are partly fixed,the fixed fibers (27) in the section (34) are connected to the device (21),the fibers (27) are cut near the second face (7) and removed to leave the passages (2) partially empty to produce the connection subassembly (36).

Abstract: We have discovered that the strength of arc fusion splices in optical fiber can be adversely affected by particles (e.g., SiO.sub.2 particles) from the electrodes. Disclosed is a method of arc fusion splicing that can substantially increase the probability that a given fiber splice will meet a given strength requirement. The method comprises initiating the arc in a "cleaning" position selected such that the probability of incidence on the fibers of particles from the electrodes is relatively low, followed by changing the relative position between the electrodes with the arc therebetween and the fibers to the conventional "heating" position and forming the splice.

Abstract: Disclosed is a fiber optic mechanical splice having one or more grooves transverse to the groove in which the optical fibers lie to dissipate air trapped in index matching material from the junction point of the optical fibers.

Abstract: A mechanical splice according to the invention does not use any adhesive for holding the aligned fibers in position. A biasing means is employed for operating upon the gripping and alignment means to align and grip the fibers, by way of a sleeve member. The biasing means is held in a preloaded state by a closure prevention means such that the biasing means cannot act to move the gripping and alignment means into the gripping state. Thus, the mechanical splice is in a preloaded and cocked condition before insertion of the optical fibers to be aligned and mechanically spliced together. Operation of the splice is quick and simple and is performed merely by movement of the closure prevention means out of the cocked position.

Abstract: Connection of hermetic optical fibers having a hermetic layer coated on optical fiber glass prepared by positioning the optical fibers on respective electrically nonconductive V-shaped grooves, aligning cores of the optical fibers and fusing and connecting the optical fibers through an aerial discharge gives a small break strength decrease after connection without removing the hermetic layer.

Abstract: An optical fiber splicer-connector comprises a fiber section, a splice section, and a connecting section. The splice section is located between the fiber section and the connecting section. A fiber channel is disposed on the fiber section for accepting an optical fiber and for guiding the optical fiber to the splice section. Means for splicing optical fibers is located on the splice section. A fiber channel is disposed on the connecting section for accepting an optical fiber and for guiding the optical fiber to the splice section. The connecting section includes a connecting body for releasably attaching the splicer to an adapter. In one embodiment, the splice section and the connecting section are provided as separate, interengagable pieces.

Abstract: A method of splicing a pair of optical fibers including, molding a base with a groove therein extending from a first inlet to a second inlet with a tapered portion at each inlet to act as a guide during the positioning of the fibers. Positioning the ends of the optical fibers in the inlets of the groove and introducing an index matching fluid into the groove. A cover having a hole therethrough may be positioned over the groove and the fluid introduced through the hole. The fluid is cured to hold the fibers fixedly in the groove and form an optical link therebetween. The cover may be molded with a perpendicular groove therein and photonic devices mounted in the cover groove.

Abstract: A fiber holding chuck comprising a silica glass rod having a fiber groove or fiber chuck for an optical fiber. The optical fiber lies in the fiber groove, and a clamping mechanism holds the optical fiber in place. The fiber holding chuck positions the optical fiber without damaging the fiber in order to align the fiber with another fiber. The clamping mechanism maintains the position of the aligned fiber. The fiber chuck mounts in a chuck groove of a chuck mounting fixture. The chuck mounting fixture attaches to a fiber positioning mechanism, and the positioning mechanism positions the chuck mounting fixture along with the fiber chuck and the optical fiber to align and splice two optical fibers together while reducing the risk of damage to the optical fiber.

Abstract: An optical fiber splice for splicing the free ends of a pair of optical fibers together, the device including a housing and a capillary tube supported therein. Each end of the housing is formed of a chamfered surface. A collet partially sits within the tapered surface. A locking nut tightens the collet against the tapered surface tightening the collet about an optical fiber.

Abstract: A method for fabricating single-mode and multi-mode attenuators characterized by a high level of wavelength insensitivity. A light source is connected to one end of a fiber and the other end is connected to an optical power meter. The optical power meter is set to a 0 dB reference. The fiber is then cut and the cut ends cleaved to define first and second segments. The ends of the segments are offset and overlapped by an axial distance that is large relative to the fiber diameter. The overlapping ends are heated so that they assume a fused state, and the relative axial positioning of the fiber ends while they are in the plastic state is adjusted to achieve the desired degree of attenuation, as indicated on the meter.

Abstract: Simple and inexpensive optical fibre splicing apparatus comprises a splicing station comprising a fibre support table and a pair of electrodes; high voltage circuitry for striking an arc; clamp assemblies at opposite ends of the table for holding end parts of aligned fibres on the table with their end faces spaced a predetermined distance apart between the electrodes, a part of at least one of the clamp assemblies being constrained to move towards and away from the other; mechanical means for controlling movement of the part of the movable clamp assembly; and a firing button for actuating the high voltage circuitry and mechanical control means. Preferably, a low voltage power source is housed in a casing separately formed with respect to the casing of the splicing station and is connected to the high voltage circuitry of the splicing station by a flexible cable.

Abstract: A self-contained unit and method for splicing together the ends of jacketed optical fibers. The unit comprises a guide to align fibers, such as a capillary tube, having opposite ends into which the ends of optical fibers to be spliced pass until they are in contact in a central portion of the guide. A heater high temperature proximal to the central portion of the guide, when activated, generates sufficient heat to fuse and splice together the contacting fiber ends. A securing means, such as spaced ferrules with a tube of ceramic material joining the ferrules, is mechanically associated with the guide to mechanically hold in position the optical fibers when spliced together. By bringing the ends of jacketed optical fibers into contact within the guide, in the vicinity of heater, and subjecting the ends to high temperature heating, the fibers are fused and spliced at their ends.

Abstract: Fusion splicing of optical fiber generally requires removal of a polymer coating from the end portions of two lengths of fiber. A conventional removal method involves immersion of the fiber ends in an appropriate polymer stripping liquid, e.g., in hot, concentrated sulfuric acid. It is known that the strength of fusion splices generally is statistically distributed, such that there exists a probability that a given splice will pass at a given proof test level. We have found that the splice strength distribution can be shifted towards higher strength if the polymer stripping liquid comprises means for insuring that the liquid is essentially free of strength-reducing particles. Preferred means are concentrated nitric acid. Exemplarily, the liquid is at a temperature in the range 170.degree.-200.degree. C. and comprises concentrated (about 95%) sulfuric acid and about 5% b.v. concentrated (about 70%) nitric acid.

Abstract: Object--to increase versatility by way of providing for the possibility of measuring losses in any of the i-th light-guides out of an arbitrary number of lightguides spliced so as to accommodate minimal air gaps, and at the joint between the (i-1)th and ith lightguides spliced without an air gap (ith joint), which is ensured by making successive measurements of the energy of reflected pulses from the energy and total power of the components of a radiation pulse from the end faces of the last and intermediate lightguides and their spliced end faces, and measuring optical losses from methematical formulas.

Abstract: A housing for a fiber optic splice protects the splice from the external to environment. Two optical fibers may be butt-coupled in a connector, which is then coated with a hard resin material. The hard resin material is then overcoated with a resilient material to provide shock protection and strain relief. The connector may be placed in a housing, which is covered and sealed to form a water-tight seal between the cover and the housing.

Abstract: Opposed ends of optical fibers are fused within a holding member, by heating the fiber ends by means positioned in, or on, the member. A self-contained package can be provided to which an electric current is applied, or some other heating method.

Abstract: An optical fiber cable of multi-core single-mode type consists of a series of groups of a plurality of optical fibers having end portions fusion spliced to corresponding end portions of adjacent groups of optical fibers at an optical connection loss of at most 0.5 dB. Each of the end portions prior to fusion splicing has a radius of curvature in meters defined by .lambda./1.41 (where .lambda. is a wavelength in .mu.m at which said optical fiber cable is used). This structure and method ensures a sufficiently low optical connection loss of the optical fibers which are economically connected in batch and are easily reconnected in case of trouble.

Abstract: A micro-welder for optical fibers includes a stand having a central support surrounded by two lateral supports or beams. The beams are suitable for moving under drive from a bending movement about respective X-axes. The stand also supports a device for securing optical fibers on the beams and a device for accurately guiding the fibers on the central support. A low accuracy first displacement device is adapted to displace the beams to bring the fibers into end-to-end contact with each other by relative translation movement along their longitudinal Z-axis which is orthogonal to the X-axes. A high accuracy second displacement device is adapted for moving the beams to drive the fibers with accurate relative translation movements along the Z-axis. Two welding electrodes are provided and an optical device which includes a microscope for observing the ends of said optical fibers.

Abstract: An apparatus for aligning a plurality of single-fiber cables, comprises a base, a cover hinged to the base and forming a gap along with the base when closed, and a pair of arms inserted in the gap and movable within the gap, for aligning the single-fiber cables in the same plane. To align single-fiber cables by means of the apparatus, the cables are arranged on the base, one after another. Then, the cover is closed, whereby the cables are located in the gap between the base and the cover. The arms or the pawl members, which are inserted in the gap, are moved, thereby putting the cables together and placing them parallel to one another in the same plane, any cable not forced above so that it rides atop another. The cables, thus aligned, can easily be held by a holder designed for multi-fiber cables.

Abstract: A method of forming low loss splices between single-mode optical fiber ends involves taking prepared fiber ends and aligning the one with the other by inserting them into opposite ends of the bore of a ferrule, and fusing the fiber ends together by applying thermal energy thereto by means of an aperture in the wall of the ferrule. Splices prepared in this way have losses of less than 0.5 dB. The use of a precisely dimensioned ceramic ferrule enables the use of splicing apparatus which does not incorporate means for 3-dimensional micromanipulation.

Abstract: Optical interconnectors and methods for optically interconnecting structures, such as printed circuit boards. The optical interconnectors comprise at least two optical fibers having one end embedded in a structure such as a printed circuit board and at least one sleeve for housing termination portions of two optical fibers. The termination portions of the fibers are positioned and secured within the sleeve so that end surfaces of the optical fibers are abutted together. The resulting optical interconnectors have low loss and occupy a small amount of space while maintaining a flat profile.

Abstract: An apparatus for aligning a plurality of single-fiber cables, comprises a base, a cover hinged to the base and forming a gap along with the base when closed, and a pair arms inserted in the gap and movable within the gap, for aligning the single-fiber cables in the same plane. To align single-fiber cables by means of the apparatus, the cables are arranged on the base, one after another. Then, the cover is closed, whereby the cables are located in the gap between the base and the cover. The arms or the pawl members, which are inserted in the gap, are moved, thereby putting the cables together and placing them parallel to one another in the same plane, any cable not forced above so that it rides atop another. The cables, thus aligned, can easily be held by a holder designed for multi-fiber cables.