Abstract: A sensing optical fiber and a sensor system which has both the functions of an optical transmission line and a sensor device and which detects many types of information from the light transmission loss. A sensing optical fiber can detect information with a high detection sensitivity by an OTDR method using Rayleigh scattered light. For this purpose, the sensing optical fiber includes a main line element which is an optical fiber installed as a light transmission line and sensor elements which are relatively short optical fibers that are inserted in intermediate parts of the main line element and whose core diameters are different from that of the main line element. The sensor system is capable of detecting various types of information obtained simultaneously with a high detection sensitivity by an OTDR method using Rayleigh scattered light.

Abstract: The object of the present invention is to provide an optical fiber fusion splice method in which two optical fibers having different mode field diameters are fusion spliced with a low splice loss without complicated words and special equipment other than a fusion splice device, and an optical fiber fusion splicer which is suitably used for the optical fiber fusion method; in order to achieve the object, the present invention provides an optical fiber fusion splice method for splicing two optical fibers having different mode field diameters comprising the steps of: arranging a first optical fiber having a small mode field diameter and a second optical fiber having a large mode field diameter so that the cut surfaces thereof face each other, heating by an electric discharge and fusion splicing the cut surfaces, shifting the heating position by an electric discharge in the first optical fiber by shifting integrally the first and second optical fibers in the longitudinal direction of the optical fibers, and addit

Abstract: A method of splicing optical fibers is provided to reduce the splicing loss of the first and second optical fibers having different MFDs from each other. In a pre-fusion heating step, the MFD at the adjacent end face of the optical fiber having larger MFD is enlarged by heating a portion including the adjacent end face thereof so as to diffuse a dopant. After the pre-fusion heating step, fusion-splicing of the first and the second optical fibers is performed. Thereafter, during the post-fusion heating step, the dopant is diffused by heating a portion including the fusion-spliced part between the first and the second optical fibers.

Abstract: A method for producing a coupler based on fiber-fused connection enabling simple, rapid production of a coupler no matter how many optical fiber core lines may be involved or no matter how small their diameter may be, comprises placing a plurality of optical fiber cords 1, 2 in parallel which comprise optical fiber core lines 3, 4 covered with jackets 7, 8 with resilient fibers 5, 6 inserted between the periphery of the core lines and the jackets; cutting a specified point of the jacket of each optical fiber core line to divide the jacket into two limbs; sliding the divided limbs (9, 9′ and 10, 10′) of the jackets in opposite directions to expose thereby sections of the underlying optical fiber core lines, the exposed sections of optical fibers being brought into contact with each other, and heated to melt to form thereby a fusion-connected section 11; sliding back each jacket limb close to the fusion-connected section; and placing the fusion-connected section 11 together with the inward ends of j

Abstract: An optical fiber splice apparatus has a covering that surrounds the splice between two optical fibers, and conducts residual pump energy in the fiber claddings away from the splice. This prevents the residual light from reaching components, such as plastic buffers, that are susceptible to failure from excess light absorption. The apparatus may use an optical epoxy covering that surrounds adjoining portions of both fibers, and that has a refractive index higher than that of the outermost fiber claddings. The covering may be surrounded by a glass capillary that is transparent to the residual light, and that conducts light from the covering further away from the splice. The capillary may be mounted in a metal housing by an adhesive epoxy that is transparent to the residual pump light, and can conduct light to an inner surface of the housing, which may be light absorbent to the wavelength range of the residual pump light.

Abstract: In a process of splicing optical fibers, a temperature distribution during the splicing of the waveguides at a constant discharge current will depend on ambient parameters, which include temperature, air pressure and air humidity, and these parameters also influence the quality of the splice being produced. The discharge current is regulated by measuring the actual intensity distribution of the thermionic emissions of the waveguide during the splicing operation and by comparing this intensity distribution with a stored reference intensity distribution. The device includes a sensor which is used for measuring the intensity distribution and for adjusting the ends of the waveguides relative to each other.

Abstract: A lens function-including optical lens according to the present invention is constituted by: at least one step-index optical fiber; and at least one gradient index optical fiber having an outer diameter equal to that of the step-index optical fiber and having a periodic length exhibiting a lens function, the gradient index optical fiber being joined or attached to an end surface of the step-index optical fiber. The present invention is especially effective in a single mode optical fiber which is typical of the step-index optical fiber. The gradient index optical fiber can be produced by an ion exchange method.

Abstract: A wavelength characteristic control device capable of variably controlling a wavelength characteristic in a satisfactory manner. A polarized light wavelength characteristic changing element has a wavelength characteristic such that the transmittances or reflectances of P- and S-polarized rays vary differently with respect to wavelength. Polarization variable control means subjects the plane of polarization of the polarized light incident on the polarized light wavelength characteristic changing element to rotatory control to change the ratio of the P-polarized ray to the S-polarized ray, thereby variably controlling the wavelength characteristic.

Abstract: A tellurite glass as a glass material of optical fiber and optical waveguide has a composition of 0<Bi2O3≦20 (mole %), 0≦Na2O≦35 (mole %), 0≦ZnO≦35 (mole %), and 55≦TeO2≦90 (mole %). The tellurite glass allows an optical amplifier and a laser device that have broadband and low-noise characteristics. In a splicing structure of non silica-based optical fiber (as a first fiber) and a silica-based optical fiber (as a second fiber), optical axes of the first and second optical fibers are held at different angles &thgr;1 and &thgr;2 (&thgr;1≠&thgr;2) respectively from a vertical axis of a boundary surface between their spliced ends, and a relationship between the angles &thgr;1 and &thgr;2 satisfies Snell's law represented by an equation of sin &thgr;1/sin &thgr;2=n2/n1 (where n1 is a refractive index of the first optical fiber and n2 is a refractive index of the second optical fiber) at the time of splicing the first and second optical fibers.

Abstract: A fusion joint between a waveguide (1a) and an optical fiber (2) is created by irradiating the interface (4) between the optical fiber and the waveguide using a laser beam. The spatial distribution of the energy furnished to the interface presents a central zone of which the energy is reduced with respect to a peripheral zone, whereby to enable a relatively high energy laser to be used while avoiding bending of the waveguide. The laser beam is caused to irradiate a higher energy density upon the waveguide than the optical fiber, typically by offsetting the center of the laser beam towards the waveguide. The fusion is performed while a force F urges the waveguide and optical fiber towards one another, so as to avoid the creation of a void at the boundary. A supplementary polymer or mineral joint can be provided.

Abstract: An optical fiber coupler for optical fiber amplifier use in the field of optical communications is provided. The optical fiber coupler comprises: a rare earth-doped fiber as an optical amplifying element; a quasi rare earth-doped fiber for entrance of input signal light; a fused-stretch fiber portion as a multiplexing element which connects a part of the rare earth-doped fiber and a parts the quasi rare earth-doped fiber, wherein the fused-stretch fiber portion formed by stretched a fused mixture of parts of the rare earth-doped fiber and the quasi rare earth-doped fiber; and a single mode fiber which is jointed at a fused joint portion to another shortened rare earth-doped fiber connected to the fused-stretch fiber portion on a side connected by the quasi rare earth-doped fiber. The quasi rare earth-doped fiber has substantially equal propagation constant to the rare earth-doped fiber without substantially containing rare earth elements.

Abstract: Method for producing a stable, multi-port fiber optic coupler that is useful for wavelength division multiplexing (WDM). The system response is substantially independent of signal polarization and is reasonably stable against mechanical stresses and elevated temperatures. Contiguous sections of two or more fiber optic lines are alternatingly heated and elongated and are twisted according to selected process parameters for selected time intervals. The fabrication procedure uses a combination of fiber heating at two or more distinct temperatures, fiber elongation and fiber twisting, applied to two or more contiguous fiber optic lines, to produce a fused fiber optic coupler with controllable wavelength discrimination and controllable signal power coupling into each output branch of the fiber optic coupler. ITU standards for wavelength discrimination and wavelength centering in a fiber optic coupler can be met by adjustment of the process parameters.

Abstract: The present invention relates to an optical fiber device having a structure for effectively restraining the splice loss from increasing between two kinds of optical fibers having respective mode field diameters different from each other. The optical fiber device comprises first and second optical fibers fusion-spliced to each other, which are partly heat-treated such that both of their respective ratios of change in mode field diameter in the longitudinal direction become a predetermined value or less after fusion-splicing. When the ratios of change in mode field diameter in the vicinity of the fused point are appropriately controlled as such, the increase in splice loss at the fused point between the first and second optical fibers is effectively suppressed.

Abstract: A passive temperature compensating package for a fiber Bragg grating device in which the fiber Bragg grating is written to the fiber prior to the temperature compensation being set. As the temperature of the package increases the fiber is de-stressed and at the desired proper resonant frequency, the fiber containing the fiber Bragg grating is secured to the package. As the package cools and expands, the fiber is pre-stressed and maintains the desired resonant frequency.

Abstract: A fiber collimator is provided, comprising at least two optical components, one of the optical components (e.g., an optical element such as a collimating lens or a plano-plano pellet) having a surface that has a comparatively larger cross-sectional area than the surface of the other optical component(s) (e.g., at least one optical fiber). The optical components are joined together by fusion-splicing, using a laser. A gradient in the index of refraction is provided in at least that portion of the surface of the optical element to which the optical fiber(s) is fusion-spliced or at the tip of the optical fiber. The gradient is either formed prior to or during the fusion-splicing. Back-reflection is minimized, pointing accuracy is improved, and power handling ability is increased.

Abstract: In a single mode optical fiber employed in an optical fiber coupler, letting r be the radial distance from the optical axis center, &Dgr;n (r) be the relative refractive index difference at the position r within a core portion with reference to the refractive index of a cladding portion placed about the core portion, &Dgr;npeak be the peak value of the relative refractive index difference &Dgr;n (r) at the position rpeak, and a be the core radius, the relative refractive index difference &Dgr;n (r) satisfies the relationship of &Dgr;n (r)≦&Dgr;npeak [1−(r/a)3] in the range of rpeak≦r≦a; and the refractive index of the cladding portion gradually decreases outward in its radial direction.

Abstract: A wavelength characteristic control device capable of variably controlling a wavelength characteristic in a satisfactory manner. A polarized light wavelength characteristic changing element has a wavelength characteristic such that the transmittances or reflectances of P- and S-polarized rays vary differently with respect to wavelength. Polarization variable control means subjects the plane of polarization of the polarized light incident on the polarized light wavelength characteristic changing element to rotatory control to change the ratio of the P-polarized ray to the S-polarized ray, thereby variably controlling the wavelength characteristic.

Abstract: An optical cable has a reduced slicing loss and superior characteristics in the efficiency of the installation work thereof, and is therefore suitable for installation on land. First and second optical fibers have been connected together by fusion splicing to form joints thereby providing an optical fiber line. Each first optical fiber has a positive chromatic dispersion at a signal light wavelength while each second optical fiber has a negative chromatic dispersion at the same wavelength. The first and the second optical fibers, including the joints, are accommodated in the optical cable.

Abstract: Techniques and devices are described for reducing splice loss in an optical transmission line. According to one technique, an electric arc is generated from an arc current, the arc current having a level and duration sufficient to produce an electric arc with an intensity and duration sufficient to achieve a desired splicing temperature at a splice point between a first optical fiber and a second optical fiber positioned within the electric arc. The electric arc is used to splice together the first and second optical fibers. After the fibers have been spliced together, the level of the arc current is ramped downward over time, thereby creating a downward ramp in temperature at the splice point from the splicing temperature to a cooler temperature, the downward ramp in temperature being shaped to reduce splice loss. The techniques and devices described herein are suitable for use with various splice combinations.

Abstract: An optical fiber holder is provided which can accurately position the tip of an optical fiber during fusion-splice. A holder 2 can be used without removing an optical fiber 1 clamped in a stripping apparatus, cleaving apparatus and fusion-splicing apparatus in common. The optical fiber is clamped between a holder main body 2a and clamping members 3a, 3b at the coated portion thereof and between a V-groove portion 2b and a clamping member 7 at the tip thereof. The holder is positioned and mounted on a holder mount 4. Since the optical fiber is kept clamped in the holder throughout the steps of stripping, cleaving and fusion-splicing, the tip of the optical fiber 1a can be accurately positioned during fusion-splice.

Abstract: A method is provided for fusion-splicing with a laser beam two optical components, one of the optical components (e.g., an optical element such as a lens) having a surface that has a comparatively larger cross-sectional area than a surface of the other optical component (e.g., an optical fiber).

Abstract: The object of this invention is to provide a method for producing a coupler based on fiber-fused connection which will enable simple, rapid production of a coupler in a highly productive manner, no matter how many optical fiber core lines may be involved or no matter how small their diameter may be.

Abstract: A method and structure for the mechanical and optical coupling of a plurality of individual planar optical devices (10, 20) to one another includes aligning the devices, bonding (35, 37, 38) the substrates (12, 22) of the planar devices (10, 20) to one another and subsequently fusing (40, 42, 44, 46) aligned optical waveguides (11, 29) utilizing a heat fusion technique. The substrates (12, 22) are bonded utilizing either heat fusion for a silica substrate or by a bonding adhesive for a silicon substrate. Once the aligned substrates (12, 22) have been mechanically bonded to one another, the optical pathways (11, 29) are coupled in one embodiment by heat fusion, preferably a focused CO2 laser (30) which completes the mechanical and optical interconnection of multiple devices. It is possible with such alignment, bonding, and fusion processes to couple numerous planar optical devices (10, 20, 50) in an array which can subsequently be packaged for use in relatively complex optical networks.

Abstract: A method for making an optical fiber fusion joint between two dissimilar single mode optical fibers (10,40) where the fibers have different core sizes and/or different refractive index profiles due to different patterns of dopant. One fiber may be a standard step-index communication fiber with a 9 &mgr;m core diameter and a numerical aperture (NA) of about 0.1, and the second fiber may be a dispersion compensating fiber (DCF) with a multiple layer refractive index profile. The second fiber alternatively may have a smaller core and a higher NA, up to about 0.3. A diffused dopant region, with a gradual longitudinal variation in diffusion, is included adjacent to the splice. The diameter of the communications fiber core increases gradually within the diffusion region as the splice joint is approached along this fiber. The diffusion of the various dopants in the second fiber tend to cause its refractive index profile to converge optically to that of the diffused step index communication fiber.

Abstract: The present invention introduces an arc shaping member to be used in fiber optic fusion splicers. The use of the an arc shaping member may minimize the undesirable effects of grunge and/or deposits than can buildup on arc electrodes. The buildup of grunge or other deposits can cause formation of an irregular electrical arc possibly resulting in an undesirable splice. The arc shaping member may be a passive or active. In a fiber optic splicer, the arc shaping member may be mounted in a plane parallel to the optical fiber(s) being spliced and in a plane perpendicular to the arc electrodes. The arc shaping member may be installed such that the member surrounds the electric arc created by the arc electrodes. The presence of the arc shaping member causes the electric arc to maintain the desired shape and/or intensity. An operator may control, independent of the arc voltage, the shape, size and heat intensity of the electrical arc.

Abstract: The present invention discloses an optical fiber fusion splicer which, together with fusing and splicing optical fibers in the state in which the jacket of each optical fiber core is clamped by being provided with a means by which a V-shaped groove base is moved up and down so that the axial centers of optical fiber cores are positioned at the proper position for electrical discharge, is provided with a mechanism that temporarily moves clamp upward and V-shaped groove base downward followed by re-clamping in order to eliminate a lift-up phenomenon during rotation alignment of the constant polarization optical fibers.

Abstract: Two optical fibers 10, 20 to be spliced are prepared (FIG. 1A), coatings of resin 12, 22 are removed from end portions of the respective optical fibers 10, 20 to expose glass fibers 11, 21 (FIG. 1B), the glass fibers 11, 21 are aligned each other (FIG. 1C), and a fusion step is carried out to heat the end faces of the glass fibers 11, 21 to cause fusion thereof to form a fusion-spliced portion A (FIG. 1D). After that, a thermal-strain-removing step is carried out to remove thermal strain by a heating treatment of a wider region R2 than a heated region R1 of the fusion-spliced portion A, at a temperature of not less than 500° C. nor more than 1500° C. (FIG. 1E).

Abstract: The present invention provides a screening mechanism for an optical fiber fusion-splicer including two holder tables for holding two optical fibers to be fusion-spliced in an opposed relationship, a connection table disposed between the holder tables and having guide grooves into which tip end portions, from which coatings are removed, of the two optical fibers held by the holder tables are fitted, and fiber clamps capable of rotating from their waiting positions to positions above the guide grooves and adapted to press the tip end portions of the optical fibers into the guide grooves, the screening mechanism comprising a sensor capable of detecting the fact that the pressing of the tip end portions of the optical fibers effected by the fiber clamps is released, and wherein, when the releasing is detected by the sensor, one or both of the holder tables are automatically shifted in directions opposite to optical fiber abutting directions to pull the optical fibers, thereby effect screening.

Abstract: Two optical fibers 10, 20 to be spliced are prepared (FIG. 1A), coatings of resin 12, 22 are removed from end portions of the respective optical fibers 10, 20 to expose glass fibers 11, 21 (FIG. 1B), the glass fibers 11, 21 are aligned each other (FIG. 1C), and a fusion step is carried out to heat the end faces of the glass fibers 11, 21 to cause fusion thereof to form a fusion-spliced portion A (FIG. 1D). After that, an additive-diffusing step is carried out to diffuse an additive added in the glass fibers 11, 21 around the fusion-spliced portion A, by a heating treatment around the fusion-spliced portion A at a first temperature of not less than 800° C. nor more than 1500° C. (FIG. 1E).

Abstract: A mini-bend optical arrangement and an associated method are described. This arrangement is designed to change the directional orientation of a light path using optical fiber. A first and a second fiber optic member define first and second light paths, respectively, which first and second members include a numerical aperture and which introduce substantial bend losses upon being bent at less than a predetermined bend radius. The first and second fiber optic members are arranged along the first and second paths preferably bent by less than the predetermined bend radius.

Abstract: An optical fiber is interfaced with an optical device formed on a substrate. The substrate includes a groove under and behind an interface between the optical fiber and the optical device. Provision of such a groove allows the substrate to be used for alignment and support of the optical fiber, while reducing fusion loss and improving durability of the interface. Steps for facilitating alignment may be provided in the substrate. Solder may be used to further improve durability of the interfaced structure.

Abstract: Each of imaging optical systems has a post-lens system having a front focus at a position of a rear focus of a pre-lens system. Each of the optical axes is set in a direction normal to the optical axes of optical fibers and different from the normal direction to a placement surface of the optical fibers. Each of image pickup planes of CCDs is inclined relative to the optical axis of the imaging optical system so that the longer an object distance of each optical fiber among the optical fibers, the shorter an image distance thereof, and each image pickup plane is located in parallel to the optical axes of the optical fibers.

Abstract: An optical fiber 2 is spliced to an optical fiber 1 in a state that those optical fibers are axially shifted away from each other by an offset quantity D. With this splicing of the optical fibers, a coupling loss arises at a fusion splicing part 1c. A plurality of fusion splicing parts 1c are provided. The terminal part of the final optical fiber of serially spliced optical fibers is a non-reflection treating part 10. Light propagating through the optical fiber 1 is attenuated at the fusion splicing part, whereby non-reflection of light is realized. The back reflection light is also attenuated at the fusion splicing part, thereby reducing the amount of the back reflection light traveling back to the core 1a of the optical fiber 1.

Abstract: A fiber-splice protection label or sleeve for one or more optical fiber fusion splices. The label is provided with a unique indicium such as a serial number in alphanumeric and/or barcoded forms. The indicium may be in the form of a strip of paper, plastic, foil, or other suitable material inserted between the inner and outer sleeve or otherwise embedded in the unit. The serial number may also be printed directly on the inner sleeve, outer sleeve, or support rod, and/or in the form of a sleeve. A hologram and/or other security feature may be used to prevent tampering or creation of counterfeit units. The number of digits are preferably chosen to allow a large number of units to be sold without duplication of numbers. Special standardized prefixes or other indicia may be chosen for government or other special applications. Serial numbers may further be encoded into a micro-miniature memory “chip” embedded in, e.g., the outer sleeve.

Abstract: A method is provided for fusion-splicing with a laser beam two optical components, one of the optical components (e.g., an optical element such as a lens) having a surface that has a comparatively larger cross-sectional area than a surface of the other optical component (e.g., an optical fiber).

Abstract: A method for fabricating a thermally expanded core (TEC) fiber including the steps of arc-fusion splicing two optical fibers having different clad outer diameters, and cutting boundary surface between an optical fiber having a small clad outer diameter and an optical fiber having a large clad outer diameter of the two optical fibers to obtain the thermally expanded core (TEC) fiber. Also, the method further includes the step of polishing the cutting face of the optical fiber having a small clad outer diameter of the two cut optical fibers.

Abstract: An add/drop filter for optical wave energy incorporates a Bragg grating in a very narrow waist region defined by merged lengths of elongated optical fibers. Light is propagated into the waist region via adiabatically tapered fibers and is transformed from two longitudinally adjacent fibers into two orthogonal modes within the air-glass waveguide of the waist and reflected off the grating from one fiber into the other. The geometry of the waist region is such that the reflected drop wavelength is polarization independent, without lossy peaks in the wavelength band of interest. Additionally, back reflection are shifted out of the wavelength band of interest. High strength gratings are written by photosensitizing the waist region fibers by constantly in-diffusing pressurized hydrogen or deuterium. For narrow spectral bandwidth gratings, dimensional variations must be minimized or compensated, and the grating is apodized by both a.c. and d.c. variations in writing beams at a net constant power.

Abstract: A method is provided for fusion-splicing with a laser beam at least two optical components to a different optical component, the different optical component (e.g., an optical element such as a lens) having a surface that has a comparatively larger cross-sectional area than a surface of the other optical components (e.g., at least two optical fibers).

Abstract: A quick restoration splice block comprises a rectangular block of transparent material including an opening for accepting the prepared endfaces of the pair of fibers to be spliced. A brightly colored indicator stripe is formed on the underside of the fiber opening. As the fiber endfaces are moved toward each other, the indicator stripe will be covered. When the stripe is no longer visible, butt-to-butt coupled of the fibers is achieved.

Abstract: In splicing optical fibers using an electric glow discharge generated between electrodes, the electric power in the glow discharge is maintained constant at varying ambient conditions, such as a varying atmospheric pressure. A signal representing the welding voltage is tapped at the middle terminal of a voltage divider circuit, and a signal representing the welding current is produced over a resistor. The signals are inputs to a multiplying circuit, the output signal of which is fed to one input of a comparator. A reference voltage is fed to the other input of the comparator. The error voltage from the comparator is an input signal to a control circuit providing a control signal to circuits for generating the voltage between the electrodes.

Abstract: In an optical amplifier wherein pumping laser light and signal laser light are multiplexed and supplied as input to a fiber doped with a rare earth element, by decreasing the number of connected sections, loss due to the connection to the rare earth-doped fiber is decreased, thereby to improve the amplifying characteristics and to simplify the production step. a pair of fibers, each which is connected by a transmitting optical fiber 1 and a rare earth-doped fiber 4, at a connected sections, are heated and fused with each other are aligned in part length to a fused jointed portion 3 which is stretched in the vicinity of the connected section 2 on the rare earth-doped fiber side, thereby forming an optical coupler.

Abstract: A fusion splicer for which maintenance can be performed efficiently is provided. A fusion splicer 1 for splicing optical fibers comprises a CCD camera 14 for capturing an image of a fusion splicing process of the optical fibers, a main memory 21 for storing image data obtained by the CCD camera 14, and a communication controller 3 adapted to make the image data transmittable and effect communication with a service station.

Abstract: A splice module for use in fiber optic cable alignment and splicing devices is disclosed, having a multi-piece v-groove module and, in one embodiment, a separately disposable electrode module such that in use only the electrode module needs to be replaced after each fiber optic cable splicing operation. The v-groove module comprises three pieces of nonconductive ceramic material held together with an adhesive. The three pieces provide for a precision v-groove for fiber optic cable alignment during mechanical splicing or fusion splicing. The electrode module includes a nonconductive ceramic with plated electrode circuit and an adhesive for mounting in the v-groove module. The electrode module provides the arc for fusing fiber optic cable and is designed to be user replaceable and inexpensive. Also disclosed is a tool and method for the easy user replacement of the electrode module of the present invention.

Abstract: An optical fiber ribbon Fusion-splicing apparatus for fusion-splicing end faces of optical fibers to each other includes an optical fiber jacket stripper including a portable main body, a power supply input terminal exposed/formed on one surface of the main body, a clamping and heating element for clamping a distal end portion of a coating of an optical fiber and heating/softening the distal end portion by using a heat accumulator which is electrically heated and has a large heat capacity, a pair of cutting blades for cutting a fiber jacket closer to a proximal end portion side of the optical fiber than the distal end portion, and a jacket stripping mechanism which is placed to oppose the clamping and heating element through the cutting blades and slides in a longitudinal direction of the optical fiber with respect to the clamping and heating element while holding the proximal end portion of the optical fiber, thereby stripping off the fiber jacket of the distal end portion, and a power supply terminal electr

Abstract: Two incipiently fused fiber ends are fused to one another by being pushed one inside the other in a longitudinal direction beyond the end face contact site by a variable amount, which is increased in proportion to the greater extent of the poorer quality of the end face as compared to the desired shape of the end face.

Abstract: A twin coupler system includes first and second optical couplers that couple a multimode pump fiber into a double-clad active primary fiber. The pump fiber carries multimode pump power from a multimode source. The primary fiber, on the other hand, carries optical information signals on the single mode core that are amplified through the pump power. A system and method for manufacturing the twin coupler system constructs the first coupler by preparing first portions of the primary and pump fibers for coupling and performing fusion and tapering operations on the primary and pump fibers at the first portions, and constructs the second coupler by preparing second portions of the primary and pump fibers for coupling and performing fusion and tapering operations on the primary and pump fibers at the second portions.

Abstract: A hermetically sealed fiber optic coupler for packaging end joined optical fibers. The device includes at least one first optical fiber having a glass-based portion having a first free end and a second optical fiber having a glass-based portion having a second free end joined to the first free end of the glass-based portion of the first optical fiber to form an end joint. The device further includes an outer chamber having at least one open end, the outer chamber surrounding the end joint, the outer chamber and the end joint being hermetically sealed with a thermosetting plastic. In the preferred embodiment, the device also includes a primary tubular sleeve, positioned between the end joint the outer chamber; epoxy for tacking the glass-based portions of the first and second optical fibers to the primary tubular sleeve; and thixotropic epoxy for hermetically sealing the ends of the primary tubular sleeve.

Abstract: A method of preparing an optical fiber for fusion splicing comprising the steps of providing an optical fiber having a fiber jacket and an end, removing a predetermined bulk of the fiber jacket from an area adjacent the end while one of substantially simultaneously moving gas over the area and exhausting gas from the area.

Abstract: A method of making short length fused fiber optical couplers and couplers made by the method. In a first step, fibers are fused by heating and pulled to form a taper section. Preferably, the fibers are twisted to assure good fusion. After pulling, in a second heating step, heat is applied to a portion of the taper section while the fibers are held stationary. The fibers are not pulled during the second heating step. The coupling ratio is monitored during the second heating step. The coupling ratio changes slowly during the second heating step and the heat is removed shortly before a desired coupling ratio is achieved. The residual heat continues to change the coupling until the desired coupling ratio is achieved. Couplers made according to the present method have a relatively short length. Couplers made according to the present method have a melted zone located in the taper section. The melted zone has a more rounded shape than the taper section due to surface tension.

Abstract: An optical circuit comprising first and second fiber optic components, an optical fiber having a first end coupled with the first fiber optic component and a second end coupled with the second fiber optic component, and a helical strand of the optical fiber intermediate the first and second components.