Abstract: An optical waveguide having stable low branching ratio is disclosed, which includes a primary optical waveguide portion coupled at a input end thereof to an input-side optical fiber. branched optical waveguide portions each having one end continuously connected to a output end of the primary optical waveguide portion and the other ends coupled to a plurality of output-side optical fibers and an introductory waveguide portion coupled to the input end of the primary optical waveguide portion and having a width substantially identical with a core diameter of the input-side optical fiber. Further, there is provided a method of producing an optical branching device in which the optical waveguide is formed.

Abstract: A dispersive optical waveguide tap comprises a blazed and chirped refractive index grating in the core of the waveguide, coupling means and utilization means. The grating is selected such that guided mode light of predetermined wavelength will, in the absence of the coupling means, be directed into one or more cladding modes of the waveguide. The presence of the coupling means in optical co-operation with the waveguide, changes the guiding conditions such that the cladding modes are substantially eliminated from a portion of the waveguide that includes the cladding, whereby the grating directs the guided mode light into one or more radiation modes. The blaze angle typically is .ltoreq.15.degree.. The chirp serves to bring the radiation mode light substantially to a focus in at least one dimension, the focal point (or line) depending on the wavelength of the light.

Abstract: The invention concerns an integrated-optical junction splitter, in particular for applications in the wavelength range of visible light, which ensures a spatial and wideband combination of light in a wavelength spectrum .DELTA..lambda. greater than 75 nm (value given applies to short-wave visible light). In the case of a usable wavelength range comprising the entire spectrum of visible light, the junction splitter is a white light junction splitter. The junction splitter consists of at least three channel waveguides, at least one of which must be a single-mode integrated-optical wideband channel waveguide (SOWCW). Two channel waveguides each have a respective input and are combined into a common SOWCW at their outputs in a coupling point, which common SOWCW features a common light output at its end.This wideband junction splitter is used as a wavelength-selective or wavelength-independent switch or modulator, in interferometric and photometric devices, sensors, and microsystem-technical solutions.

Abstract: Optical signals that would otherwise transit a first fiber (12), but for a break therein, may be cut-over to a second fiber (16) by clamping the first fiber at first and second spaced locations thereon upstream and downstream, respectively, of the break. Clamping the first fiber creates a microbend at each of the first and second locations at which optical signals exit from, and may be injected into, respectively, the first fiber. The second fiber is likewise clamped at first and second spaced locations thereon to create a pair of microbends at which optical signals may be injected into, and extracted from the second fiber, respectively. Once the first and second fibers are clamped in this fashion, the optical signals extracted from the first fiber at the first location are coupled into the second fiber and then extracted therefrom for injection into the first fiber at the second location thereon.

Abstract: The invention comprises a fiber optic management system with a tray having a first fiber optic receiving area to receive an input optical fiber. A second fiber optic receiving area receives a tap fiber. A fiber optic splice connector is disposed between the first and the second fiber optic receiving area to receive the input fiber from one side and the tap fiber from another side. The first and the second fiber optic receiving areas can be loaded with their respective fibers without disturbing the other fiber optic receiving area.

Abstract: A nonlinear Y-junction waveguide structure includes a straight linear waveguide, and a nonlinear waveguide partially joined to the linear waveguide and bent through a desired angle at an output end portion thereof, whereby incident light coming into the linear waveguide travels mainly along the linear waveguide when it has a power lower than a predetermined level while traveling mainly along the nonlinear waveguide when it has a power not lower than the predetermined level. The nonlinear Y-junction waveguide structure has an increased branching angle as compared to the conventional completely-operating optical device and exhibits an abrupt switching phenomenon. Accordingly, it is possible to achieve an easy adjustment of the critical power. In this regard, there is no difficulty in the fabrication of the waveguide structure.

Abstract: A wavelength selective optical fiber coupler having various applications in the field of optical communications is disclosed. The coupler is composed of dissimilar waveguides in close proximity. A light induced, permanent index of refraction grating is recorded in the coupler waist. The grating filters and transfers energy within a particular range of wavelengths from a first waveguide to a second waveguide. Transversely asymmetric gratings provide an efficient means of energy transfer. The coupler can be used to combine or multiplex a plurality of lasers operating at slightly different wavelengths into a single fiber. Other embodiments such as a dispersion compensator and gain flattening filter are disclosed.

Abstract: Digital data in the form of a light signal is to be transmitted through an optical network of optical waveguides joined together at passive node points. The node points split or branch off the light signal from a primary waveguide into secondary or branch waveguides. The passive node points include special coupling surfaces respectively a coupling body including a flat surface and a prismatic structure arranged at the junction or head end of the secondary waveguide. The respective coupling surface or coupling body achieves an exactly defined maximum reflection of the light in the primary waveguide, i.e. constrains a major proportion of the light within the primary waveguide. Thus, maximum light power is maintained and transmitted along the primary waveguide, and at each node point a defined minimum light power is coupled into the respective secondary waveguides.

Abstract: A method for preparing a fiber-optic polarizer involves a first step in which the cladding layer of a single-mode optical fiber is side-polished to form a planar surface contiguous to the core region of the single-mode optical fiber. The planar surface is formed thereon a buffer dielectric/metal composite thin film, or the planar surface is coated by sputtering with a metal layer which is then coated with a medium having a refractive index matching to that of the optical fiber. The polishing of the single-mode optical fiber is done by using a semiconductor substrate having one or more V-shaped recesses having a large curvature radius.

Abstract: An optical device including a lens located between a first port and a second port, and a photodetector having a photodetecting surface located in the vicinity of the second port. The first port and the second port have a first aperture and a second aperture, respectively. The lens has a converging portion for converting a light beam so as to couple the first aperture and the second aperture, and a deflecting portion for deflecting a part of a light beam from the first port to make the part incident on the photodetecting surface. The converging portion and the deflecting portion are integral with each other, for example. By using this optical device, light power can be monitored stably with no polarization dependence.

Abstract: A method and apparatus for tapping and distributing light propagating through a polymer optical fiber (POF). Within the polymer optical fiber, one or more mirrors are constructed. At a point in the POF where an internal mirror is constructed, light traversing the POF is efficiently diverted out of the polymer optical fiber upon striking the mirror. The light so diverted passes through a dispersing region such that only diffuse light is emitted and may be put to an advantageous use. Alternatively, a controllable shutter is placed within the polymer optical fiber such that light traversing the POF is diverted out of the polymer optical fiber upon striking the mirror when the controllable shutter so permits. The controllable shutter is variable so that variable amounts of light may be selectively emitted from the POF.

Abstract: An arrangement for switching a high-voltage switch by optical energy is proposed. The high-voltage switch comprises a number of controllable semiconductor elements, which switch through when illuminated with light. The light energy is transmitted via a light guide or optical fiber rod, and the angle between the light guide or optical fiber rod and the high-voltage switch is from 5.degree. to 20.degree., and the light guide or optical fiber rod is cut obliquely on its end toward the high-voltage switch, producing an elliptical cross section.

Abstract: A power monitoring system including a vertical cavity surface emitting laser generating an emission. A beam splitter optically positioned to receive the emission and split the emission into a first portion and a second portion. A monitor optically positioned to receive the first portion of the emission. An output of the monitor is used to control emissions of the vertical cavity surface emitting lasers.

Abstract: The invention provides an optical coupling switch and flat panel display including an array of such optical coupling switches. The optical coupling switch includes a light storage plate adapted to set up conditions for total internal reflection such that light injected into the plate is internally reflected. A light tap is disposed proximal to a coupling surface of the light storage plate for coupling internally reflected light out of the light storage plate and into the light tap when the light tap is brought into contact with the light storage plate coupling surface. The light tap is capable of movement in a direction perpendicular to the light storage plate in response to an applied electrostatic force. The optical coupling switch includes a scattering mechanism, such as a scattering surface or scattering medium, for scattering light in the light tap into a viewing volume.

Abstract: An optical device 201, having one or more input waveguides 25 coupled to one side of a slab waveguide 20 and an array of output waveguides 26 coupled to an other side of the slab waveguide, is improved by including a transition region 22 immediately adjacent to the slab that operates to reduce insertion loss between the waveguide array 26 and the slab waveguide. The transition region includes a number of silica paths (a.sub.I . . . a.sub.n) that intersect the waveguide array. The silica paths have widths W(a.sub.n) that progressively decrease as they become further away from the slab waveguide. The silica paths are parallel to each other and perpendicular to the waveguide array. Disclosed embodiments include an M.times.N star coupler, a Dense Waveguide Division Multiplexer, and a 1.times.N power splitter. In each of these embodiments, insertion loss is substantially reduced over similar devices not employing such a transition region.

Abstract: This invention relates to a novel design for a low-loss optical power splitter, in particular Y-branch types resulting from chemical vapor deposition (CVD) fabricated silica waveguides. More specifically, the present invention utilizes mode matching of the fundamental modes between the input and the output waveguides of a splitter to optimize the splitters operational performance. The optical power splitter of the present invention comprising an input waveguide region having a predetermined width (W) and capable of transmitting optical energy having a fundamental mode E.sub.1.sup.0. Additionally, the splitter includes at least two output waveguide regions positioned to receive at least a portion the optical energy from the input waveguide region wherein the output waveguide regions each have predetermined widths (w) and are capable of transmitting optical energy having a fundamental mode E.sub.2.sup.

Abstract: The apparatus of this invention includes a macrobend/microbend unit which imposes first and second macrobends, and microbends between the first and second macrobends, on an optical fiber under analysis. If light is travelling in one direction on the optical fiber, the bending of the optical fiber is such that some light will escape from the core of the optical fiber at the first macrobend. A first photodetector is arranged to receive light emitted from the first macrobend, and generates a signal indicative of whether light is present at the first macrobend. If light is travelling in the optical fiber in the other direction, the second macrobend causes some light to be emitted. A second photodetector arranged to receive light from the second macrobend, generates a signal indicative of whether light is present at the second macrobend.

Abstract: A fiber optic coupler for coupling an asymmetrical beam such as provided by a laser diode into a fiber optic cable. The coupler comprises at least one fiber optic cable having a first end including a tapered section that has an approximately flat coupling facet for receiving the asymmetrical beam and an approximately flat tapered surface adjacent to the coupling facet for reflecting the rapidly diverging radiation, a main body for receiving and transmitting the reflected laser radiation, and an output end having an approximately flat output facet. A support structure situates the coupling facet proximate to the laser diode. A second, approximately flat tapered surface may be formed in the tapered section opposite the first tapered surface. The fiber optic cable may have any cross-section, such as circular, rectangular, or square.

Abstract: An optical fiber having a conductive layer disposed therearound has sections removed therefrom that form gaps that expose the underlying optical fiber. Light manifolds are formed at each gap, such as are provided by Bragg gratings photoinduced in the core at each gap, and photoconductive material is disposed at each of the gaps. An opaque coating may optionally be disposed over the outside of the photoconductive material to ensure that it is activated by light propagating within the optical fiber. Light transmitted down the fiber may be controllably coupled output of the fiber at each of the gaps. The optical fiber thus provides multiple functions including electrical conductor, light manifold, and substrate on which the photoconductive material is deposited.

Abstract: An optical amplification system directs a diffraction-limited signal beam through a series of approximately 90.degree. crossings with a number of non-diffraction-limited pump beams in a photorefractive medium. All of the beams are s-polarized, resulting in an energy transfer from the pumps to the signal beam while leaving the signal beam diffraction-limited. The photorefractive medium is preferably a series of BaTiO.sub.3 :Rh crystals that receive the pump and signal beams through orthogonal faces, with their C-axes at approximately 45.degree. to both beams. A binary tree optical distribution network is used to minimize waveguide splits in forming a large number of pump beams.

Abstract: This invention comprises a multi-mode optical "T"-splitter for the coupling of multi-mode optical fibers to, from, and between other fibers, sources, detectors, and other optical elements, and method of fabricating same. The optical T-splitters of this invention may use tubular waveguides to provide a better match with round fibers, resulting in higher efficiency, lower loss, and other improvements. The optical T-splitter is comprised of waveguides forming a substantially T-shaped geometry in a substrate. A reflecting element is inserted at the junction of the "T" to split input light entering one of the legs of the "T" into light being output between the other two legs of the "T". The "T" configuration of these tubular channels and the insertion of various types of reflecting elements at the "T" junction, make it possible to perform any number of optical functions, including splitting, tapping, mixing, and coupling.

Abstract: A method and apparatus for tapping and distributing light propagating through a polymer optical fiber (POF). Within the polymer optical fiber, one or more mirrors are constructed. At a point in the POF where an internal mirror is constructed, light traversing the POF is efficiently diverted out of the polymer optical fiber upon striking the mirror. As such, the light which is diverted is effectively tapped off and may be put to an advantageous use.

Abstract: A method for tuning fiber optic coupler and wavelength division multiplexer devices comprises the steps of fusing optical fibers having a refractive index responsive to ultraviolet radiation to form a coupling region having a coupling ratio dependent upon the refractive index, and subjecting the coupling region to ultraviolet radiation to adjust the coupling ratio to a predetermined value at a given operating wavelength.

Abstract: A fused optical fiber coupler comprising a first pair of axially elongated cylindrical fibers, each having a circular transverse cross-section of a first diameter, the first pair of fibers being in fused contact with each other along a continuous line and forming grooves on opposite sides of the line. A second pair of axially elongated cylindrical fibers each having a circular transverse cross-section of a second diameter different than the first diameter of the first pair of fibers, one fiber from the second pair of fibers being disposed in each of the grooves and fused to each of the first pair of fibers.

Abstract: In a case where an arrayed optical fiber coupler obtained from a tape ribbon 1 is fixed to an reinforcement case 3, a glass portions 2b as a non-elongated portion outside of the elongated portions 2c of the coupler and a protection coating layers 2a at the back thereof are fixed to the reinforcement case 3 with an adhesive layer 4. A collectively coating resin layer 1a of the tape ribbon 1 is not fixed to the reinforcement case 3. The resin layer 1a is fixed to the reinforcement case 3 with a soft adhesive layer 5 different from the above adhesive layer 4, if necessary. As the resin of the adhesive layer 4, there is preferable an adhesive having the viscosity of 50 to 200 P and thermosetting property in addition to ultraviolet cure property.

Abstract: The present invention relates to an optical system for providing uniform illumination of a light valve. The light source is an extended source generally emitting a non-uniform spatial distribution of light power. Source light is focused into the entrance end of a light transmitting tunnel having reflecting interior wall surfaces and having cross sectional and length dimensions chosen to deliver, at the exit end of the tunnel, light which is substantially uniform in power distribution over the surface area of the exit end. This is caused by multiple reflections from the tunnel walls. The exiting light is advantageously used to illuminate uniformly a light valve. The tunnel may be tapered to alter the exit angular aperture. The tunnel may be hollow or filled with a transparent material. In addition, the tunnel may be segmented and folded to provide a joint which conforms tunnel geometry to given spatial limitations between source and valve.

Abstract: A beam splitter is an optical multilayer film obtained by sequentially stacking first to fifth layers respectively having refractive indexes of n.sub.1 to n.sub.5 and geometrical thicknesses d.sub.1 and d .sub.5 on a substrate having a refractive index n.sub.G. The refractive indexes of the substrate and the first to fifth layers satisfy any one of a relationship of n.sub.G =1.45 to 1.60, n.sub.1 =2.02 to 2.20, n.sub.2 =2.25 to 2.38, n.sub.3 =1.44 to 1.47, n.sub.4 =2.25 to 2.38, and n.sub.5 =1.44 to 1.47, a relationship of n.sub.G =1.45 to 1.60, n.sub.1 =1.44 to 1.47, n.sub.2 =2.25 to 2.38, n.sub.3 =1.44 to 1.47, n.sub.4 =2.25 to 2.38, and n.sub.5 =2.02 to 2.20, and a relationship of n.sub.G =1.45 to 1.60, n.sub.1 =1.44 to 1.47, n.sub.2 =2.25 to 2.38, n.sub.3 =2.02 to 2.20, n.sub.4 =2.25 to 2.38, and n.sub.5 =1.44 to 1.47, and a geometrical thickness d.sub.i of an ith layer of the first to fifth layers satisfies relation n.sub.i d.sub.i cos (.theta..sub.i)=.lambda./4, where n.sub.

Abstract: An optical integrated circuit provides multiple power splitting functions and comprises a plurality of optical power splitters networked together. In one embodiment, the optical integrated circuit has two 2.times.2 optical power splitters ganged together such that the circuit simultaneously provides two different 1.times.2 power splitting functions and four different 1.times.3 power splitting functions. In another embodiment, the optical integrated circuit has three 2.times.2 optical power splitters ganged together such that the circuit simultaneously provides two 1.times.2 power splitting functions, four 1.times.3 power splitting functions, and two 1.times.4 power splitting functions. Since each integrated circuit provides more than one power splitting function, the integrated circuit is more versatile than a single power splitter.

Abstract: The multi-fiber optical cross-coupler includes N peripheral fibers and a central fiber that are coupled together optically. The method of the invention for manufacturing such a cross-coupler consists in forming a multi-waveguide conductor by drawing a composite primary preform, the waveguides of the conductor being cylindrical elementary fibers embedded so that they are mutually parallel in mechanical and optical coupling cladding, said waveguides defining the fibers of the cross-coupler, and having opto-geometrical characteristics so that they are optically coupled over a defined length of said conductor, which length is cut off accordingly. Application to an optical coupler.

Abstract: An integrated optical device for tapping signal power provides a tap which is substantially independent of wavelength and polarization. The optical device includes a first tap consisting of a first optical waveguide carrying an input signal S disposed in coupling relation with a second optical waveguide for providing an output cross-state transmission T.sub.1. The cross-state transmission T.sub.1 is polarization and wavelength dependent. The optical device further includes a second tap consisting of a third optical waveguide disposed in coupling relation with and in series with the second optical waveguide carrying the output cross-state transmission T.sub.1 for providing an output bar-state transmission T.sub.2. The bar-state transmission T.sub.2 has an opposite dependency on waveguide coupling than that of the cross-state transmission T.sub.1 and, thus, compensates for wavelength and polarization dependencies of the cross-state transmission signal T.sub.

Abstract: A two-way line monitor has a signal beam splitter, first and second optical sensors and a mirror. The beam splitter is positioned on the light axis and angled so as to receive first and second input lights at 20 to 40 degrees of the angle of incidence. The first and second optical sensors arranged so as to receive first and second sample lights, reflected from the beam splitter and the mirror, at around 20 degrees of the angle of incidence.

Abstract: An apparatus and method for fabricating directional fiber optic taps having a variety of output angles. The taps can be used to monitor losses due to misalignment of the fiber or losses due to bending and straining of the fiber. The apparatus and method can also be used to fabricate taps which filter out higher order modes in a fiber. The apparatus and method can also be used to produce taps which can be used in a position or refractive index measuring system.

Abstract: A V groove and guide grooves are defined in a ceramic substrate, and an optical fiber is fixedly disposed in the V groove by the ceramic substrate and a cover, thereby producing a first optical waveguide chip. A V groove and guide grooves are also defined in another ceramic substrate, and an optical fiber is fixedly disposed in the V groove by the ceramic substrate and a cover, thereby producing a second optical waveguide chip. The first optical waveguide chip has an end face inclined to the direction of propagation of light through the optical fiber thereof, and the second optical waveguide chip also has an end face inclined to the direction of propagation of light through the optical fiber thereof. The first and second optical waveguide chips are positioned relatively to each other by guide pins intimately placed in the guide grooves, and the inclined end faces extend substantially parallel to each other with an air layer interposed therebetween.

Abstract: A first optical waveguide chip has a ceramic substrate and a cover, and the ceramic substrate has a V groove and guide grooves with an optical fiber being fixed in the V groove. A second optical waveguide chip has a ceramic substrate and a cover, and the ceramic substrate has a V groove and guide grooves with an optical fiber being fixed in the V groove. The first and second optical waveguide chips have respective end faces inclined 62.degree. to the direction in which light is propagated through the optical fibers. The first and second optical waveguide chips are positioned by guide pins intimately fitted in the guide grooves.

Abstract: A device for tapping an optical fiber is adapted to engage a fiber supporting structure, such as a tray, having an aperture therein and a fiber passing over the aperture, the fiber tray and the clip-on device having a 3-point, nested contact which essentially restricts all relative movement between the tray and the device in the contact plane, providing improved repeatability in the positioning of the optical fiber in the head of the device, and thus improving repeatability of the optical measurements. A similar 3-point, nested contact may be used to align a mandrel housing with a fiber guide in the head, prior to a mandrel engaging the optical fiber. The mandrel housing is slidably received in a cylinder, and may have an elliptical outer surface which fits in an elliptical inner surface of the cylinder, to prevent rotation of the mandrel housing within the cylinder.

Abstract: The invention is a fiberoptic coupler formed by multiple optical fibers each having a core and a surrounding cladding and at least one spacer fiber having the refraction index substantially matched to the refraction index of the cladding of at least one adjacent optical fiber. The optical and spacer fibers are arranged, over a region extending axially through a limited length coupling region, in a side-by-side configuration wherein each fiber touches neighboring fibers. The coupling region is created by laterally fusing all fibers and is adapted to couple propagating modes of light between the optical fibers. Various configurations of the coupler include an arrangement of seven equal diameter fibers with a center fiber surrounded by six fibers, or an arrangement of nineteen equal diameter fibers with a center fiber surrounded by a first ring of six close-packed fibers and a second ring of twelve close-packed fibers.

Abstract: The present invention relates to an optical fiber component, which includes an optical component, (e.g., a glass tube), one or more glass optical fibers attached to the surface of said component, and a surface pretreatment layer, formed from a silane applied to the surfaces of the component and the one or more glass optical fibers. Preferably, an adhesive is applied over the surface pretreatment layer to strengthen attachment of the component to the one or more glass optical fibers. A method of preparing such optical fiber components is also disclosed.

Abstract: An optical tap for selecting a signal of only a certain wavelength from transmitted signals which are wavelength division-multiplexed. The tap transmits signals of other wavelengths as they are. The tap has an input optical fiber for receiving the wavelength division-multiplexed signals, a first diffraction grating for dispersing the incident light through a different angle for each different wavelength, a reflecting mirror for reflecting the certain wavelength of the dispersed light signal to select this wavelength, a first output fiber for delivering only the selected light, a second diffraction grating which concentrates the unreflected light, and a second output fiber for delivering the unselected wavelengths.

Abstract: The present invention comprises a waveguide substrate and an optical waveguide disposed on the substrate, the optical waveguide having an optical waveguide region as a light transmission path, an insertion region for inserting an optical functional component having a mode field width of light propagating therein larger than that of light propagating in the optical waveguide region, and an optical connection region provided between the optical waveguide region and the insertion region to change a mode field width of light propagating therein.

Abstract: An optical network includes an erbium-doped silica-based optical fibre having a D-shaped cross-section. The wave-guide carries information signals at 1.53 .mu.m from a signal source and provides amplification to the information signals when pumped by an optical pump source operating at 0.994 .mu.m. Optical signals are tapped from the waveguide by means of evanescent couplers. The waveguide provides amplification to at least partially restore tapping loss to the information signal due to the optical taps. The core of the optical waveguide is chosen to substantially minimize the spot size of signals at the wavelength of the pump source so as to provide preferential extraction of the information signal in order to leave the pump source substantially undisturbed to be able to pump regions of the amplifying waveguide beyond the optical tap.

Abstract: A coupler (1) made of optical fibers is provided with a device for detecting the light that is carried in one of the fibers at the coupler output in operation. For that purpose, the coupler (1) embedded in an enclosure (2) has at the coupler output a lens body (8) enclosing the optical fiber (pigtail 6) and a detector (9) aimed at the lens body (8). With the detector, during coupler operation, lost light dissipated via the primary coating of the optical fiber is received by the lens body (8 ) and carried by the detector (9) to an electrical evaluator.

Abstract: Light transferred between an optical fibre housed within a fibre management unit and an optical device external to the fibre management unit. The transfer arrangement incudes an aperture formed in the fibre management unit, a mandrel mounted in the fibre management unit adjacent to the aperture and positioned so that the optical fibre lies between the mandrel and the aperture, and a probe housing the optical device. The probe is provided with an optical head in optical communication with the optical device, and with an arrangement for moving the optical head into the aperture so as to deform the optical fibre against the mandrel sufficiently to permit light to be tapped between the optical fibre and the optical head.

Abstract: An optical fiber switching apparatus having a guide frame which is supported by an apparatus body. The guide frame has a guide groove. Disposed on the guide grooves is a movable moving member. The moving member can be moved by the apparatus along the guide groove. A slide terminal is connected by a support to the moving member. The support allows the slide terminal to approach the moving member and thereby causing the slide terminal to enter an unlocked position or to move away from the moving member and thereby causing the slide terminal to enter a locked position. The slide terminal support an end face of an optical fiber. The apparatus also includes a driving wire which has two end portions. The end portions are disposed through the moving member and are coupled to the slide terminal, thereby forming a loop in the driving wire.

Abstract: In the manufacture of a wavelength multiplexing 2.times.2 tapered fused fiber coupler by progressive stretching, the birefringence of the coupler resulting from the progressive stretching is subsequently nulled-out by elastic twisting of the coupler. The progressive stretching is performed, under temperature conditions providing a profile in the coupling region of the coupler having the property that the coupling strength for one of the principal polarization planes of the coupler remains substantially constant during said elastic twisting.

Abstract: A 1 X N splitter for single-mode optical fiber includes an individual single-mode optical fiber having its junction end juxtaposed, through a focusing lens/junction element, to the end of a bundle of arbitrarily arranged single-mode fibers which are fused together along a portion of their lengths and which have a total diameter approximately equal to the diameter of the first single-mode fiber.

Abstract: An optical power splitter for the distribution of high-power light energy has a plurality of prisms arranged about a central axis to form a central channel. The input faces of the prisms are in a common plane which is substantially perpendicular to the central axis. A beam of light which is substantially coaxial to the central axis is incident on the prisms and at least partially strikes a surface area of each prism input face. The incident beam also partially passes through the central channel.

Abstract: A tapered waveguide for transmitting optical signals from a signal source to an optical fiber is fabricated by irradiating a layer of prepolymer resin on a substrate with a converging beam of ultraviolet light, whereby the irradiated resin polymerizes into a clear, hard polymer and the resin that has not been irradiated remains in its resinous state. The unpolymerized resin is removed with an organic solvent. The variation in width of the waveguide is achieved by varying the distance between the source of the converging beam of ultraviolet light, thereby varying the diameter of the spot that is being irradiated, while simultaneously moving the source of ultraviolet light parallel to the axis of the waveguide. Variation in thickness of the waveguide is achieved by sloping the substrate.

Abstract: The optical element provides for the displacement of two end sections having slanted end faces. The slanted end faces have such an angle to the optical axis of the fiber, that the limit angle for total reflection is exceeded. The displacement remains substantially below the diameter of the fiber.

Abstract: Apparatus is provided for coupling the optical energy conducted through an optical fiber to an electro-optic hybrid element, such as a photodetector, that is positioned within a hybrid casing. The outer jacket of the fiber is stripped, cleaved to 45 degrees and silvered or coated with a dielectric to form a mirror for directing the optical energy through the side of the cladding. A window, transparent to a predetermined bandwidth of the optical energy, is provided in the lid of the case overlying the electro-optic element. The mirrored end of the fiber is positioned above the window and the element while the fiber is fixed to the top of the lid of the casing. The arrangement requires no ferrule and permits bakeout and testing of the hybrid package prior to engagement of the optical fiber.

Abstract: An achromatic fiber optic coupler of the type wherein a plurality of single-mode optical fibers, each having a core and a cladding, are fused together along a portion of the lengths thereof to form a coupling region. The propagation constants of the fibers are preferably equal; however if the fiber claddings have different refractive indices, the lowest cladding refractive index is n.sub.2. A matrix glass body of refractive index n.sub.3 surrounds the coupling region, n.sub.3 being lower than n.sub.2 by such an amount that the value of .DELTA..sub.2-3 is less than 0.125%, wherein .DELTA..sub.2-3 equals (n.sub.2.sup.2- n.sub.3.sup.2)2n.sub.2.sup.2.