Abstract: A method of preparing an optical preform, comprises the steps of: positioning an optical preform comprising silica within a cavity of a furnace; passing an etchant gas into the furnace and at least one of through an open channel defined in the optical preform and around the optical preform; and passing a neutralizing gas into the cavity of the furnace, the neutralizing gas configured to neutralize the etchant gas.

Abstract: Provided is a manufacturing apparatus for manufacturing a soot deposition body, including a main burner that deposits glass microparticles on a target rod while moving parallel to a longitudinal direction of the target rod; and a side burner that is positioned outside of a movement range of the main burner in a movement direction of the main burner, and fires an end portion of the soot deposition body formed on the target rod. The side burner includes a plurality of heating burners arranged distanced from each other in a circumferential direction of the target rod. In the manufacturing apparatus described above, the main burner may include a plurality of deposition burners that are arranged distanced from each other in the circumferential direction of the target rod.

Abstract: An optical fiber preform includes: a columnar portion having an approximately constant radius of r; and a taper portion located adjacent to the columnar portion in a lengthwise direction and having a radius decreasing along the lengthwise direction. The taper portion includes: a first taper portion including a portion having a radius varying between 0.9r and 0.6r; and a second taper portion including a portion having a radius varying between 0.4r and 0.15r. A diameter of the first taper portion in the portion having the radius varying between 0.9r and 0.6r decreases so as to form a maximum angle ?1 between 40 degrees and 60 degrees with respect to the columnar portion, a diameter of the second taper portion in the portion having the radius varying between 0.4r and 0.

Abstract: High aspect ratio core optical fiber designs, which could be semi-guiding, including a core region having a first refractive index and a high aspect ratio elongated cross-section along a slow axis direction, are described. An internal cladding having a second refractive index sandwiches the core and acts as a fast-axis signal cladding. The core has an edge region at both of its short edges that is in contract with edge-cladding regions having a barbell shape. The refractive index of the core regions, the refractive index of the internal claddings, and the refractive index of the edge-cladding regions, are selected so as to maximize the optical power of a lowest-order mode propagating in the fiber core, and to minimize the optical power of the next-order modes in the fiber core. A process to fabricate such a high aspect ratio core fiber is also provided.

Abstract: Methods for producing a semifinished part for the manufacture of an optical fiber are disclosed. The methods are optimized in terms of bending. The methods include the steps of providing a shell tube with a shell refractive index which is lower in relation to the light-conducting core. Then, at least one protective, intermediate and/or barrier layer is applied to a radially outermost and/or innermost tube surface of the respective shell tube, wherein a build-up of light-conducting layers is realized on the inner side and/or the outer side of the shell tube. Finally, the shell tubes are joined by collapsing so as to form the semifinished part.

Abstract: Methods for making active laser fibers include the production of an optical fiber with disturbed (or deviated) cylindrical symmetry on the glass surface of the fiber. The methods include a preform containing a central core made of glass. In one embodiment, the preform is circular and surrounded by additional glass rods and an outer glass jacket tube. In a first alternative embodiment, this preform is merged during fiber drawing. In a second alternative embodiment, the preform merged in a process forming a compact glass body with disturbed cylindrical symmetry. This compact preform is drawn into a fiber under conditions maintaining the disturbed cylindrical symmetry.

Abstract: Methods for making fiber waveguides include rolling a multilayer structure into a spiral structure and forming the fiber waveguide from the spiral structure. The forming includes drawing a fiber preform derived from the spiral structure.

Abstract: Methods to fabricate an optical preform for draw into Polarization Maintaining (PM) or Polarizing (PZ) optical fiber are provided. The methods involve assembly of pre-shaped and pieced together bulk glass elements into preforms (“assembled preforms”) for simultaneous fusing and drawing into optical fiber. These preforms form a stress-induced birefringent optical core when drawn to fiber.

Abstract: Armored fiber optic assemblies are disclosed that include a dielectric armor along with methods for manufacturing the same. The dielectric armor has an armor profile, thereby resembling conventional metal armored cable to the craft. The dielectric armor provides additional crush and impact resistance and the like for the optical fibers and/or fiber optic assembly therein. The dielectric armor is advantageous to the craft since it provides the desired mechanical performance without requiring the time and expense of grounding like conventional metal armored cables. Additionally, the armored fiber optic assemblies can have any suitable flame and/or smoke rating for meeting the requirements of the intended space.

Abstract: The present invention is generally directed to a method of making a hollow-core photonic band gap preform from a specialty glass by pressing a specialty glass through a die to form a tube wherein the outer transverse shape of the tube is a hexagon, triangle, quadrilateral, or other polygon; stretching the tube to form a micro-tube with approximately the same outer transverse shape as the tube; stacking a plurality of micro-tubes into a bundle minimizing voids between adjacent micro-tubes and forming a central longitudinal void wherein the plurality of micro-tubes within the bundle comprise an inner structured region of the preform and the central void of the bundle comprises a hollow core in the preform; and inserting the bundle into a jacket tube. Also disclosed are the hollow-core photonic band gap preform and fiber formed by this method.

Abstract: An optical fiber includes an outer periphery formed into a shape that configures the fiber to interlock with the other fibers with complementary shapes. Methods and systems for fabricating such interlocking fibers are also disclosed. In one example, a method includes drawing a first optical fiber from a preform and forming an outer periphery of the first optical fiber into a shape that configures the first optical fiber to be interlocked with a second optical fiber comprising an outer periphery formed into a shape that is complementary to the shape of the first optical fiber.

Abstract: An optical fiber includes a core (1a) having an oblong rectangular or square cross section and made of quartz, and a cladding (2) surrounding the core (1a), having a circular outer cross-sectional shape, and made of resin.

Abstract: Optical devices, components and methods for mounting optical fibers and for side-coupling light to/from optical fibers using a modified silicon V-groove, or silicon V-groove array, wherein V-grooves, which are designed for precisely aligning/spacing optical fibers, are “recessed” below the surface of the silicon. Optical fibers can be recessed below the surface of the silicon substrate such that a precisely controlled portion of the cladding layer extending above the silicon surface can be removed (lapped). With the cladding layer removed, the separation between the fiber core(s) and optoelectronic device(s) can be reduced resulting in improved optical coupling when the optical fiber silicon array is connected to, e.g., a VCSEL array.

Abstract: The invention relates to a method and an apparatus for producing optical glass elements, in particular optical prisms or optical rod lenses, using a drawing process. The geometry of the glass strand which is to be produced is controlled by means of cooling or heating elements positioned at least around portions of the periphery or longitudinal axis of the glass strand, inside or outside the heating apparatus.

Abstract: An optical fiber includes a core (1a) having an oblong rectangular or square cross section and made of quartz, and a cladding (2) surrounding the core (1a), having a circular outer cross-sectional shape, and made of resin.

Abstract: Methods and apparatus provide for birefringent waveguides suitable for optical systems exhibiting polarization dependence such as interferometer sensors including Sagnac interferometric fiber optic gyroscopes (IFOG). The waveguides, for some embodiments, may offer single polarization performance over lengths of about a kilometer or more due to polarization dependent attenuation. According to some embodiments, the waveguides incorporate a pure silica core for resistance to radiation-induced attenuation (RIA).

Abstract: A method for manufacturing a single mode optical fiber with a reduced PMD (Polarization Mode Dispersion), by drawing an optical fiber preform composed of a core and a clad surrounding the core, includes (a) heating the optical fiber preform to a high temperature using a furnace, and drawing an optical fiber from an outlet of the furnace at a linear velocity (Vf) of 500 mpm or above by means of neck-down drawing; and (b) impressing a spin on the optical fiber by means of a spin impressing device provided on a drawing path of the optical fiber, wherein a maximum spatial frequency of spin (y) impressed on the optical fiber satisfies the following equations Exp ? ( 24 ? t - 12 ) ? y ? - 20 × log ( V f 500 ) + 25 and t=(0.21×CladOval)+(0.04×CoreOval)+(0.17×ECC), where y is a maximum spatial frequency of spin [turns/m], Vf is a drawing velocity [mpm], CladOval is a clad ovality [%], CoreOval is a core ovality [%], and ECC is an eccentricity [?m].

Abstract: Included among the many structures described herein are photonic bandgap fibers designed to provide a desired dispersion spectrum. Additionally, designs for achieving wide transmission bands and lower transmission loss are also discussed. For example, in some fiber designs, smaller dimensions of high index material in the cladding and large core size provide small flat dispersion over a wide spectral range. In other examples, the thickness of the high index ring-shaped region closest to the core has sufficiently large dimensions to provide negative dispersion or zero dispersion at a desired wavelength. Additionally, low index cladding features distributed along concentric rings or circles may be used for achieving wide bandgaps.

Abstract: Methods and apparatus provide for birefringent waveguides suitable for optical systems exhibiting polarization dependence such as interferometer sensors including Sagnac interferometric fiber optic gyroscopes (IFOG). The waveguides, for some embodiments, may offer single polarization performance over lengths of about a kilometer or more due to polarization dependent attenuation. According to some embodiments, the waveguides incorporate a pure silica core for resistance to radiation-induced attenuation (RIA).

Abstract: A method for manufacturing a single mode optical fiber with a reduced PMD (Polarization Mode Dispersion), by drawing an optical fiber preform composed of a core and a clad surrounding the core, includes (a) heating the optical fiber preform to a high temperature using a furnace, and drawing an optical fiber from an outlet of the furnace at a linear velocity (Vf) of 500 mpm or above by means of neck-down drawing; and (b) impressing a spin on the optical fiber by means of a spin impressing device provided on a drawing path of the optical fiber, wherein a maximum spatial frequency of spin (y) impressed on the optical fiber satisfies the following equations Exp ? ( 24 ? t - 12 ) ? y ? - 20 × log ( V f 500 ) + 25 and t=(0.21×CladOval)+(0.04×CoreOval)+(0.17×ECC), where y is a maximum spatial frequency of spin [turns/m], Vf is a drawing velocity [mpm], CladOval is a clad ovality [%], CoreOval is a core ovality [%], and ECC is an eccentricity [?m].

Abstract: According to one embodiment a method of making optical fibers comprises: (i) manufacturing a core cane; (ii) situating a plurality of microstructures selected from rods, air filled tubes and glass filed tubes and placing said microstructures adjacent to the core cane, said microstructures forming no more than 3 layers; (iii) placing the core cane with said adjacent microstructures inside a holding clad tube; and (iv) placing interstitial cladding rods inside the holding (clad) tube, thereby forming an assembly comprising a tube containing a core cane, a plurality of microstructures and interstitial cladding rods. The assembly is then drawn into a microstructured cane and an optical fiber is drawn from the microstructured cane. According to several embodiments, the method of making an optical fiber includes providing at least one air hole and at least one stress rod adjacent to the core.

Abstract: A method and system of forming vertical optical interconnects in optical integrated circuits is disclosed. The method includes forming a first optical transmission layer over a substrate. A first cladding layer is then formed on the first optical transmission layer and portions of the first cladding layer removed to form an angled sidewall in the first cladding layer. An optical interconnect layer is formed on the angled sidewall of the first cladding layer and on an exposed portion of the first optical transmission layer.

Abstract: An optical fiber having a length can include a core and at least one cladding disposed about the core, where the one cladding can comprise at least first volumetric regions having a first refractive index n1 and second volumetric regions having a second refractive index n2, different from n1, and the first and second volumetric regions in any cross-section taken through the fiber can be randomly intermingled with one another, where the random intermingling of the first and second volumetric regions changes with changes in the location of the cross-section along the length of the fiber.

Abstract: A method of manufacturing an optical waveguide having a core and a clad. The method includes forming a first clad by applying a resin on a substrate and curing the resin, applying a core material between a recessed mold which has a recess having a shape identical to a shape of the core and the first clad which is provided on the substrate, curing the core material applied, thereby forming a core pattern having a shape corresponding to that of the recess, and peeling the recessed mold from the core pattern and the first clad.

Abstract: Based on an intermediate 20A in which a cladding portion 22 is formed on the outer periphery of a core portion 21, a pair of holes 23 and 24 are provided parallel to the z axis on both sides of the core portion 21 within the cladding portion 22, and an intermediate 20 is thereby fabricated. In this intermediate 20, a width Ry in the y-axis direction is made smaller than a width Rx in the x-axis direction. Moreover, a cylindrical stress applying part 33 is inserted into a hole 23 of the intermediate 20, and a cylindrical stress applying part 34 is inserted into a hole 24 thereof. Thus, a preform 40 is formed. These materials are drawn and integrated together, and a polarization maintaining optical fiber is thereby manufactured.

Abstract: A method for manufacturing an optical waveguide component with several layers stacked on a silicon substrate. The layers include a buffer layer, a first substrate, a guiding layer on the buffer layer and including an optical waveguide, and an outer layer as protection against external stresses. The layers are made from an organic-inorganic hybrid using a sol-gel process. An additional layer is disposed on the guiding layer so that a symmetrical structure is produced that has the same refractive index around the waveguide in the guiding layer.

Abstract: Disclosed is a method of producing an elliptic core optical fiber, in which a original preform having a circular core disposed at the center of a circular clad is processed to flatten on its periphery to form a processed preform that is then drawn with heating into an elliptic core optical fiber. According to the invention, the form of the processed preform used for producing an elliptic core optical fiber with desired specific dimensions can be designed using pre-obtained correlations based on the dimensions of the elliptic core optical fiber. If the processed preform designed like this is drawn with heating, an elliptic core optical fiber with desired specific dimensions can be reliably and easily produced.

Abstract: A fast (high numerical aperture) cylindrical microlens, which includes an internally reflective surface, that functions to deviate the direction of the light that enters the lens from its original propagation direction is employed in optically conditioning laser diodes, laser diode arrays and laser diode bars.

Abstract: High index-contrast fiber waveguides, materials for forming high index-contrast fiber waveguides, and applications of high index-contrast fiber waveguides are disclosed.

Abstract: Disclosed is an optical fiber article for receiving pump radiation of a first wavelength for amplifying or generating radiation of a second wavelength. The optical fiber article includes a core for propagating light of the second wavelength. The core has a first index of refraction and includes a rare earth material. A cladding surrounds the core and has a second index of refraction that is less than the first index of refraction. The outer circumference of the cladding can include a plurality of sections, where the plurality of sections includes at least one substantially straight section and one inwardly curved section. The optical fiber article can also include at least one outer layer surrounding the cladding, where the index of refraction of the outer layer is less than the second refractive index. Methods for producing the optical fiber article are also disclosed, as well as methods for providing a preform for drawing such an optical fiber article.

Abstract: Based on an intermediate 20A in which a cladding portion 22 is formed on the outer periphery of a core portion 21, a pair of holes 23 and 24 are provided parallel to the z axis on both sides of the core portion 21 within the cladding portion 22, and an intermediate 20 is thereby fabricated. In this intermediate 20, a width Ry in the y-axis direction is made smaller than a width Rx in the x-axis direction. Moreover, a cylindrical stress applying part 33 is inserted into a hole 23 of the intermediate 20, and a cylindrical stress applying part 34 is inserted into a hole 24 thereof. Thus, a preform 40 is formed. These materials are drawn and integrated together, and a polarization maintaining optical fiber is thereby manufactured.

Abstract: A process for forming an integrated optical device in a substrate, comprising the steps of: providing a substrate having a base index of refraction; providing a UV light beam; focusing the beam on a portion of the substrate in order to form a region of increased refraction; and scanning an elongated region of the glass substrate with the beam in order to define at least one elongated optical channel having an increased index of refraction relative to the base index of refraction, the elongated optical channel for guiding light transmitted there along. The process further includes: forming a plurality of elongated optical channels in the substrate, wherein a first optical channel is operative for transmitting light to the plurality of elongated optical channels such that the transmitted light is divided among the plurality of elongated optical channels, thereby forming an optical beamsplitter.

Abstract: The invention relates to a method of making an optical fiber and an optical fiber made in accordance with the inventive method. The method includes the step of drawing an optical fiber from a multiple crucible apparatus, wherein one of the crucibles of the apparatus has a non-symmetrical orifice (not shown). The inventive fiber has at least a core and cladding. At least one section of the inventive fiber includes an orientation element.

Abstract: A method for making a highly birefringent optical fiber includes providing a preform with a substantially circular cross section. The preform includes a core region having a substantially circular cross section and a substantially elliptical cladding region adjacent the core region. The outer surface of the preform is modified to create a shaped preform with a non-circular cross section. The shaped preform is then drawn at a temperature and draw rate sufficient to provide an optical fiber with the non-circular cross section of the shaped preform.

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: The present invention relates to a method of forming a crucible. The method includes the steps of (a) bottoming one end of a tube thereby forming a substantially closed end; (b) heating the closed end to a forming temperature; (c) contacting an interior surface of the closed end with a forming tool, thereby altering the interior surface of the closed end to form at least one section with a predetermined wall thickness; and (d) manipulating the at least one section of the closed end to form an orifice.

Abstract: High index-contrast fiber waveguides, materials for forming high index-contrast fiber waveguides, and applications of high index-contrast fiber waveguides are disclosed.

Abstract: Disclosed is a method of producing an elliptic core optical fiber, in which a original preform having a circular core disposed at the center of a circular clad is processed to flatten on its periphery to form a processed preform that is then drawn with heating into an elliptic core optical fiber.

Abstract: An optical fiber having optical characteristics that systematically vary along its length is made by inserting a plurality of cylindrical tablets into a cladding glass tube and overcladding the tube with particles of cladding glass. Each tablet contains a core region, and it optionally contains a layer of cladding glass Adjacent tablets are capable of forming optical fiber sections having different optical properties. Prior to consolidating the glass particles, chlorine flows through the tube and over the tablets. When the tube begins to sinter, the chlorine flow is stopped and the sintering particles generate an inwardly directed force that causes the tube to collapse inwardly onto the tablets which concurrently become fused to each other. The resultant draw blank can be drawn into a low loss optical fiber. This method is particularly useful for making dispersion managed single-mode optical fibers.

Abstract: An optical fiber with a non-circular cross-section is realized by creating a void having the desired cross-section in a housing and filling the void with an optical material. This structure is then collapsed to solidify it and drawn to desired dimensions. The optical material may be rods, soot or ground material.

Abstract: Our method of making high bandwidth silica-based multimode optical fiber comprises provision of a non-circular preform, and drawing fiber of chiral structure from the preform. The non-circular preform can be made by maintaining the inside of the tubular preform under reduced pressure during at least part of the collapse, resulting in a non-circular core and cladding. It can also be made by removal (e.g., by grinding or plasma etching) of appropriate portions of the preform, resulting in a circular core and non-circular cladding. In the latter case, fiber is drawn at a relatively high temperature such that, due to surface tension, the cladding assumes substantially circular shape and the core assumes a non-circular shape. The chiral structure is imposed on the fiber in any appropriate way, e.g., by twisting during fiber drawing the fiber alternately in clockwise and couterclockwise sense relative to the preform.

Abstract: A ribbon fiber is formed of a plurality of aligned especially processed fibers having a bare fiber portion subjected to predetermined fabrication, and a ribbon portion of 2 to 30O mm in length formed on some of the bare portion; the ribbon fiber being manufactured in such a manner that the specially processed fibers are aligned with a precise pitch width while a length is adjusted so that a lengthwise position of the portion processed as predetermined has a predetermined accuracy, and then a part thereof is fixed by and coated with an adhesive to form a ribbon portion, thereby a ribbon fiber with a great easiness and less expensive is manufactured, and thus manufactured optical fiber can be used to form a fiber array or a half-pitch fiber array.

Abstract: An optical waveguide fiber suitable for making a spliced connection between two dissimilar optical waveguide fibers, the method of making the fiber, and the method of splicing dissimilar fibers to lower splice losses.

Abstract: A glass preform (10) is drawn into a fiber. Holes (13), running the length of the preform (10), collapse during the drawing, this causes the core (11) to have an elliptical cross section.

Abstract: An optical fiber having optical characteristics that systematically vary along its length is made by inserting a plurality of cylindrical tablets into a cladding glass tube and overcladding the tube with particles of cladding glass. Each tablet contains a core region, and it optionally contains a layer of cladding glass Adjacent tablets are capable of forming optical fiber sections having different optical properties. Prior to consolidating the glass particles, chlorine flows through the tube and over the tablets. When the tube begins to sinter, the chlorine flow is stopped and the sintering particles generate an inwardly directed force that causes the tube to collapse inwardly onto the tablets which concurrently become fused to each other. The resultant draw blank can be drawn into a low loss optical fiber. This method is particularly useful for making dispersion managed single-mode optical fibers.

Abstract: A method for making preforms for use in a glass lens molding process and molding lenses is disclosed. A glass rod is formed preferably by dipping a bob into a homogeneous melt of a predetermined optical glass, maintaining the temperature of the homogeneous melt at least the melt temperature and producing a rod of glass from the homogeneous melt, allowing the rod of glass to cool and solidify, and then cutting the rod of glass into predetermined lengths. By withdrawing the bob at a predetermined pull rate the rod of glass can be produced with a predetermined diameter. Using a constant pull rate, the rod of glass will be cylindrical in shape and can be cut into a series of individual cylindrical preforms. The preforms can be inserted into a compression molding apparatus for the forming of a glass optical element therewith. The orientation of the preform is such that the cut planar surfaces of the preform are parallel to the direction of compression of the molding process.

Abstract: A method of making a fiber having a single mode absorptive core whose position relative to the cross sectional plane of the inner multimode cladding varies along the length of the fiber. A groove or grooves are made in the outer cladding of the preform. When fiber is drawn from the grooved preform, the position of the core does not follow the centerline of the fiber; the position within the fiber varies in accordance with the grooves.

Abstract: Optical fiber according to the invention comprises a core, with an inner cladding surrounding the core, and an outer cladding surrounding the inner one. The fiber comprises preform-derived glass. The outer cladding comprises a first outer cladding region between the inner cladding region and a second outer cladding region. The first outer cladding region is selected to have an effective refractive index less than 1.35, and such that the optical characteristics of the optical fiber are essentially independent of the second outer cladding, and/or such that the fiber is re-coat insensitive. The first outer cladding typically comprises elongate features extending in the fiber axial direction, with a web material joining the inner cladding to the second outer cladding. The elongate features are filled with a low-index material, exemplarily air, but could of course be evacuated. Fibers according to the invention have many uses, e.g., cladding-pumped optical fiber or fiber with a long period grating.

Abstract: A cladding-pumped fiber structure, suitable for use as a laser, provides for efficient clad-to-core energy transfer. The outside interface of the pump-clad is constructed from a rod-shaped preform by local melt-displacement using an open flame.

Abstract: A method of producing an elliptic core type polarization-maintaining optical fiber comprises the steps of providing a glass rod comprising a cladding glass layer around the periphery of a core glass layer, the cladding glass layer having a softening point higher than the softening point of the core glass layer, removing two side surface portions of the glass rod by machining along the axial direction of the glass rod to form a machined rod noncircular in cross section, outside depositing fine silica glass particles on the periphery of the machined rod, followed by sintering to provide a support glass layer having a softening point higher than the softening point of the cladding glass layer, and drawing the thus obtained glass rod body as an optical fiber preform. Since the portion for constituting the core of the optical fiber is formed by machining, the core is permitted to have a high ellipticity.