Abstract: An IR-transmitting glass fiber configured to include a holey-microstructured core and a cladding surrounding the core. Glass material used at least in the core is one of the heavy metal oxide glasses, where the glass network former is an oxide selected from GeO2, TeO2, Sb2O3, and Bi2O3, while each and every component of the fiber includes only an oxide glass material and is devoid of any other materials.

Abstract: A method for manufacturing an optical fiber preform that includes preparing a glass cylinder with inner and outer surfaces forming at least part of a cladding portion are repeatedly polished, and a glass core rod that includes a core portion having a higher refractive index than the cladding portion; and inserting the core rod into the glass cylinder and heating the glass cylinder and core rod to form a single body. The repeated polishing of the inner surface of the glass cylinder includes passing pure water that does not contain a cutting fluid over the inner surface for at least the final polishing. The polishing is preferably performed using a polishing cloth to which are affixed diamond abrasive grains. The glass core rod and the glass cylinder are preferably formed of composite quartz glass.

Abstract: Provided is a method of manufacturing an optical fiber base material having at least four layer including a core, a first cladding, a second cladding containing fluorine, and a third cladding. The manufacturing method comprises preparing a starting base material that includes the core and the first cladding; forming a porous intermediate glass base material by supplying glass raw material and oxygen to a high-frequency induction thermal plasma torch to synthesize glass fine particles that are then deposited on a surface of the starting base material; forming an intermediate glass base material that includes the core, the first cladding, and the second cladding containing fluorine, by heating and vitrifying the porous intermediate glass base material in an atmosphere containing fluorine; and providing the third cladding on the outer surface of the intermediate glass base material.

Abstract: An optical waveguide element includes a cladding portion made of a silica-based glass, and an optical waveguide positioned in the cladding portion and made of a silica-based glass in which a ZrO2 particle is dispersed.

Abstract: A method of manufacturing microchannel plate according to an embodiment of the present invention includes: a first step of fabricating a multifiber having a polygonal cross-section by bundling a plurality of fibers; a second step of fabricating a microchannel plate base material by use of a plurality of the multifibers; and a third step of fabricating a microchannel plate out of the microchannel plate base material. The plurality of fibers include: a first fiber whose predetermined-thickness outer circumferential part surrounding a center part including a core is formed of a predetermined-component glass material; and a second fiber whose both center part including a core and outer circumferential part surrounding the same are formed of the predetermined-component glass material. The second fiber is arranged at, at least, one corner of a polygonal cross-section of the multifiber.

Abstract: Core rod sections useable for production of finished optical fiber preforms are fabricated by inserting one or more core body pieces axially end-to-end inside a glass cylinder, thereby defining joints between adjacent ones of the inserted pieces. The cylinder is mounted with the contained core body pieces in the region of a furnace. The glass cylinder and core body pieces are heated together in the furnace, thereby elongating the cylinder and the core body pieces contained in the cylinder, and the cylinder collapses to form a finished core rod. Core rod sections are cut from the finished core rod at positions that coincide with the joints between the core body pieces. One or more of the cut core rod sections are useable for the production of optical fiber preforms.

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 specification describes methods for the manufacture of very large optical fiber preforms wherein the core material is produced by MCVD. Previous limitations on preform size inherent in having the MCVD starting tube as part of the preform process are eliminated by removing the MCVD starting tube material from the collapsed MCVD rod by etching or mechanical grinding. Doped overcladding tubes are used to provide the outer segments of the refractive index profile thus making most effective use of the MCVD produced glass and allowing the production of significantly larger MCVD preforms than previously possible.

Abstract: Methods for modifying preform core ovality during and subsequent to the formation of an optical fiber preform. After MCVD deposition forms the core rod, but prior to overcladding of the core rod, the code rod may be etched to change its ovality. In order to etch the core rod, the core rod may be mounted to lathe, rotated by at least two rotors, and subjected to a heat source. Additionally, one of the at least two rotors may be phase-shifted from another one of the at least two rotors after the core rod is mounted on the lathe.

Abstract: An optical fiber preform is fabricated by inserting a number of core body pieces end-to-end inside a glass cylinder, wherein the pieces may have a cladding-to-core diameter (D/d) ratio within the range of one to four. The cylinder with the inserted core body pieces is mounted vertically on a furnace and heated so that the cylinder becomes elongated and its outside diameter collapses to form a core rod from which core rod sections with D/d ratios greater than five, can be cut. A soot overcladding is deposited on the circumference of a core rod section until the diameter of the deposited soot builds to a determined value. The core rod section with the deposited soot overcladding is consolidated to obtain a finished optical fiber preform. The preform preferably has a D/d ratio of about 15 or more, and an optical fiber may be drawn directly from the preform.

Abstract: An optical fiber sensing cable is disclosed. The optical fiber sensing cable comprises a fiber with a core having an index of refraction n1, and a circumferential surface of the fiber including a nanoporous cladding having an index of refraction index n2. The methods of preparing the fiber sensor cable, including forming the nanoporous cladding and the sensor systems incorporating the optical fiber sensing cable of this invention are also disclosed.

Abstract: A system for producing a tapered fiber optic component, the system including a support platform, coupled with a first end of an optical fiber, a weight suspended from a second end of the optical fiber, such that the weight applies longitudinal pulling pressure on the optical fiber, and a moveable heater, positioned adjacent to a predetermined area of the optical fiber, the predetermined area is positioned between the first end and the second end of the optical fiber, the moveable heater applying thermal energy to the predetermined area of the optical fiber, when the optical fiber is lengthened by the pulling pressure, the movable heater follows the predetermined area, such that the movable heater remains adjacent to the predetermined area of the optical fiber.

Abstract: Core rods or other glass components associated with optical fiber preforms are cleaned by loading them into a number of first sleeves, and partially obstructing entrance and exit ends of the sleeves to retain the components. The sleeves are contained inside a second sleeve so that the entrance ends of the first sleeves face an entrance end of the second sleeve. A fluid delivery system supplies cleaning fluids to the entrance end of the second sleeve, so that the fluids enter the first sleeves and contact exposed surfaces of the loaded components. The fluids leave the exit ends of the first sleeves and purge from an exit end of the second sleeve. Separators may be placed between the components in the first sleeves to enhance cleaning action and to cushion adjacent end faces of the components. Cleaned components may be unloaded from the first sleeves without risk of contamination.

Abstract: A method of making an article having channels therethrough includes the steps of: providing a ductile structure defining at least one macro-channel, the macro-channel containing a salt; drawing the ductile structure in the axial direction of the at least one macro-channel to reduce diameter of the macro-channel; and contacting the salt with a solvent to dissolve the salt to produce an article having at least one microchannel.

Abstract: A method for manufacturing an optical fiber probe includes the steps of providing an optical fiber including a core and a outer protective layer disposed therearound; removing a portion of the outer protective layer to expose a portion of the core; etching the exposed portion of the core to achieve a predetermined shape and thus form a detector; surrounding the detector with a gel solution containing metal particles; and evaporating a solvent in the gel solution to form a metal layer on the surface of the detector.

Abstract: An optoelectronic device has at least a first facet (S), a first waveguide (2) and a second waveguide (3). The waveguides are substantially coincident at the first facet (6), such that light travelling along the first waveguide (2) is reflected into the second waveguide (3) by the first facet (6). The first facet (6) is formed by precision cleaving. Preferably an etch feature is incorporated in the same mask level as that to define the waveguide core.

Abstract: A method of making optical quality films is described. A silica film is deposited on a wafer by PECVD (Plasma Enhanced Chemical Vapor Deposition). The deposited film is then subjected to a first heat treatment to reduce optical absorption, wafer warp, and compressive stress. A second film is deposited. This step is then followed by a second heat treatment to reduce optical absorption, wafer warp and tensile stress. The two heat treatments have similar temperature profiles.

Abstract: A photonic connection includes a first fiber and a second fiber. The first fiber has a core with a first predetermined pattern defined on or in a facet thereof, and the second fiber has a core with a second predetermined pattern defined on or in a facet thereof. The second predetermined pattern is complementary to the first predetermined pattern such that the first fiber or the second fiber fits into another of the second fiber or the first fiber at a single orientation and position.

Abstract: An optical fiber according to Tran U.S. Pat. No. 5,274,728 is improved by chemically etching the surface of the GeO2-based glass perform with an acid solution based on a mixture of HNO3 and water.

Abstract: A method of forming an alkali metal oxide-doped optical fiber by diffusing an alkali metal into a surface of a glass article is disclosed. The silica glass article may be in the form of a tube or a rod, or a collection of tubes or rods. The silica glass article containing the alkali metal, and impurities that may have been unintentionally diffused into the glass article, is etched to a depth sufficient to remove the impurities. The silica glass article may be further processed to form a complete optical fiber preform. The preform, when drawn into an optical fiber, exhibits a low attenuation.

Abstract: An as-deposited waveguide structure is formed by a vapor deposition process without etching of core material. A planar optical device of a lighthouse design includes a ridge-structured lower cladding layer of a low refractive index material. The lower cladding layer has a planar portion and a ridge portion extending above the planar portion. A core layer of a core material having a higher refractive index than the low refractive index material of the lower cladding layer overlies the top of the ridge portion of the lower cladding. A slab layer of the core material overlies the planar portion of the lower cladding layer. The lighthouse waveguide also includes a top cladding layer of a material having a lower refractive index than the core material, overlying the core layer and the slab layer. A method of forming an as-deposited waveguide structure includes first forming a ridge structure in a layer of low refractive index material to provide a lower cladding layer.

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: Provided is an optical transmission substrate including: a first substrate; an optical waveguide which has clad covering a core and a periphery of the core and extends on an upper surface of the first substrate; a second substrate provided parallel to the first substrate so that a lower surface thereof contacts an upper surface of the optical waveguide; a reflection surface which is provided on a cross section of the core at an end of the optical waveguide and reflects light, which travels through the core of the optical waveguide, toward the second substrate; and a light guide which is provided in the second substrate and guides the light, which is reflected toward the second substrate, toward an upper surface of the second substrate from a position closer to the core than an upper surface of the clad.

Abstract: The present invention relates to a method of manufacturing a solid preform by moving a heat source parallel to the longitudinal axis of a substrate tube, whose inner surface is coated with one or more doped or undoped glass layers, so as to collapse the substrate tube into the solid preform in a number of passes, with an etchant being supplied to the interior of the substrate tube after a number of passes of the heat source.

Abstract: A method for forming and apparatus comprising a free space coupler region having a plurality of optical waveguides coupled to the space coupler region at an interface region, the waveguides converging with one another to the interface region, and a trench formed between adjacent waveguides, the depth of the trench or trenches extending from an outer point to the interface region and monotonically decreasing in depth from the outer point to the interface region.

Abstract: A waveguide having an angled surface is created by depositing an optical core material onto a substrate having two levels. In one embodiment, a high density plasma deposition may be used to deposit the optical core material.

Abstract: A leached fiber bundle with the light outlet points positioned as accurately as possible is provided, in which the end faces are not completely fused together, but rather are only fused together at their contact surfaces. The interstices formed are permanently filled with adhesives with the aid of a pressure reduction. To protect the optical fibers from mechanical load, adhesives are introduced into the transition region between the fixed end region and a flexible region. This allows the leached fiber bundles to be produced more economically and also improves their service life.

Abstract: The specification describes a VAD method for producing optical fiber preforms by depositing soot onto a solid core rod. The solid core rod preferably has a uniform composition, doped or undoped, suitable for the center core region of the preform. The primary cladding layer, and additional cladding layers if desired, are produced by depositing soot on the center core rod. The surface of the center core rod is treated with an etchant torch that traverses the center core rod in front of the soot deposition torch. This produces a clean interface between the core and primary cladding. This soot-on-center-core-rod method allows the production of sharp index profiles by reducing the diffusion of dopants into and out of the center core portion of the preform that occurs in soot-on-soot processes.

Abstract: A microchannel plate (P) for receiving photoelectrons includes a plate-like substrate web (W) formed from a plurality of micro-tubules (10) of a single type of cladding glass (12) and defining a pair of opposite faces (14a and 14b). The substrate web (W) further includes a plurality of microchannel passages (16) extending between the opposite faces (14a and 14b) and having openings (18a and 18b, respectively) in both of the opposite faces (14a and 14b). The microchannel openings (18) have funnel-like entries or openings (20) formed in the substrate web (W) with at least one of the opposite faces (14).

Abstract: The present invention provides methods for manufacturing microstructured optical fibers having an arbitrary core size and shape. According to one embodiment of the invention, a method of fabricating a photonic band gap fiber includes the steps of forming an assembly of stacked elongate elements, the assembly including a first set of elongate elements, the first set of elongate elements defining and surrounding a core volume, and a second set of elongate elements surrounding the first set of elongate elements, wherein the core volume defined by the first set of elongate elements has a shape that is not essentially an integer multiple of the external shape of the elongate elements of the second set of elongate elements; including the assembly in a photonic band gap fiber preform; and drawing the photonic band gap fiber preform into the photonic band gap fiber.

Abstract: A method of making an optical waveguide preform includes forming a preform including a first portion and a second radial portion, wherein the second portion includes a dopant, and wherein the first portion exhibits a density greater than the second portion. The method further includes stripping at least a portion of the dopant from the second portion. In a preferred embodiment, the stripped dopant has migrated in a previous processing step.

Abstract: This invention relates to a method of preparing an optical fiber preform with the preform having a uniform refractive index profile for the deposited oxide material that ultimately forms the optical fiber core. One embodiment of the invention relates to a process for preparing an optical fiber preform comprising the steps of etching a substrate a first time to remove a portion of a deposited oxide material from the preform by using a gas comprising an etchant gas containing fluorine at a sufficient temperature and gas concentration to create a fluorine contamination layer in the remaining deposited oxide material; and etching the preform a second time using a gas comprising an etchant gas containing fluorine at a sufficient temperature and gas concentration to remove the fluorine contamination layer without any substantial further fluorine contamination of the remaining deposited oxide material. Further embodiments relate to similar processes.

Abstract: A method for fabricating a GRIN fiber includes forming a tube of silica-glass having a tubular core and a concentric tubular cladding adjacent and external to the tubular core. The core has a dopant density with a radially graded profile. The method includes partially collapsing the tube by applying heat thereto. The partially collapsed tube has a central channel. The method includes passing a glass etchant through the central canal to remove an internal layer of silica glass, and then, collapsing the etched tube to a rod-like preform.

Abstract: A laser gain medium and a method of manufacturing a laser medium, such as a laser rod, or slab for use in high-powered laser peening systems. A laser medium and method reduces stress risers along the surface of the amplifier medium by grit blasting, polishing, etching, annealing, and by eliminating platinum inclusions within the laser glass.

Abstract: Fiber is drawn from a preform comprising a silica body, e.g., a sol-gel derived overcladding or substrate tube. Prior to sintering, the body is treated with a gaseous mixture containing one or more non-oxygenated sulfur halides, to remove and/or reduce the size of refractory oxide particles, and/or dehydroxylate the body. Removal of metal oxide particles or reduction in their size contributes to drawing of optical fiber exhibiting desirable strength, since such particles act as initiation sites for breakage. Advantageously, the halides include sulfur chlorides, which provide desirable improvements compared to treatment by oxygenated sulfur chlorides such as thionyl chloride (SOCl2).

Abstract: A mesh (36) is placed around a bundle (32) of fused glass fibers. The bundle is then immersed in a leaching bath (44). The ends of the bundle are protected from the bath fluid by furrules (34). Some of the glass of the bundle is leached out, so as to provide a flexible fiber bundle.

Abstract: The present invention provides a method of preparing preforms for optical fibers. The invention allows one to remove or significantly reduce undesirable refractive index variations in the central portion of the optical fibers. The method of preparing the preform having a central duct includes the steps of a first collapsing step, an etching step and a second collapsing step. The first collapsing step reduces the size of the central duct without closing the central duct by heating the preform at a first preform collapsing temperature. A portion of the last deposited layer of the core glass layers is etched by flowing an etchant gas through the central duct at a lower temperature than the preform collapsing temperature. The preform is finally collapsed at a second collapsing temperature to close the central duct of the preform and form a solid rod.

Abstract: The present invention relates to a method of manufacturing a solid preform by moving a heat source parallel to the longitudinal axis of a substrate tube, whose inner surface is coated with one or more doped or undoped glass layers, so as to collapse the substrate tube into the solid preform in a number of passes, with an etchant being supplied to the interior of the substrate tube after a number of passes of the heat source.

Abstract: A method for performing high aspect ratio gap fill during planar lightwave circuit top clad deposition. A plurality of waveguide cores are formed on a substrate, the waveguide cores having a plurality of gaps there between. A cladding layer is formed over the waveguide cores and the substrate using a high-density plasma deposition process. The refractive index of the waveguide cores are controlled by using a dopant to be higher than the refractive of the cladding layer. An anneal process is performed on the cladding layer after the high-density plasma deposition process. The gaps between the waveguide cores can be smaller than 2 microns. The aspect ratio of the gaps between the waveguide cores can be greater than 3. The high-density plasma deposition process provides a very high purity USG (undoped silica glass) and BPSG (Boron Phosphorous silica glass) layers having a uniform refractive index.

Abstract: An apparatus for forming a loop in a filament comprising a first wall having a first guide slot formed therein and a second wall having a second guide slot formed therein coplanar and parallel to the first guide slot. The first wall is opposite the second wall and each of the guide slots has opposing ends. A first gripper holds a filament at a first location. The first gripper is mounted from the first wall to the second wall at an end of each of the first guide slot and the second guide slot. The apparatus also includes a movable gripper to hold the filament at a second location. The movable gripper has a separation from the first gripper and is mounted from the first wall to the second wall adjacent to the other end of each of the first guide slot and the second guide slot for movement towards the first gripper to reduce the separation between them. This produces a loop of filament between the first gripper and the moveable gripper.

Abstract: A method for manufacturing a base material of optical fibres having a desired ratio of core to clad, including forming a porous base material upon depositing glass particles, producing a core member upon dehydrating and vitrifying the porous base material, adding a clad member onto the core member, is characterized in that the method includes, a step of dehydrating the porous base material in an atmosphere of gas including helium and chlorine within an electric furnace; a step of vitrifying the porous base material in an atmosphere of inert gas including helium; and a step of providing a purging step of heating the porous base material in an atmosphere of inert gas mainly including helium between the dehydrating step and the vitrifying step.

Abstract: The present invention concerns waveguides made from porous glass which have been doped with certain selected materials which exhibit optical properties. In the context of the invention, the selected materials are optical materials which exhibit optical activity or a Faraday effect, such as an electro-optic material, and more specifically a polymer. Devices made according to the present invention can be used as phase modulators.

Abstract: An optical waveguide substrate is prepared by forming grooves in a silicon substrate in accordance with the pattern of a desired waveguide device, thermally oxidizing the silicon substrate to form a peripheral quartz layer surrounding the grooves, burying in the grooves a doped quartz glass layer having a higher refractive index, abrading the surface of the resulting structure to be flat, and forming on the flat surface a glass layer having a lower refractive index. An optical waveguide substrate featuring no distortion of the core pattern, little warp, and a low loss can be produced in a simple manner.

Abstract: The present invention relates to a method for collapsing a hollow substrate tube into a rod-like preform while heating by reciprocating a heating element along the length of the substrate tube. The present invention is characterized in that a constant electric power is supplied to the heating element during collapsing.

Abstract: This invention relates to a method of preparing an optical fiber preform with the preform having a uniform refractive index profile for the deposited oxide material that ultimately forms the optical fiber core. One embodiment of the invention relates to a process for preparing an optical fiber preform comprising the steps of etching a substrate a first time to remove a portion of a deposited oxide material from the preform by using a gas comprising an etchant gas containing fluorine at a sufficient temperature and gas concentration to create a fluorine contamination layer in the remaining deposited oxide material; and etching the preform a second time using a gas comprising an etchant gas containing fluorine at a sufficient temperature and gas concentration to remove the fluorine contamination layer without any substantial further fluorine contamination of the remaining deposited oxide material. Further embodiments relate to similar processes.

Abstract: An exposed part of at least one of two optical fibers with different mode field distributions to be fusion spliced is heated by a burner, to thereby continuously vary its mode field distribution in the longitudinal direction of the optical fiber, and the exposed end part of at least one of the optical fibers is cleaved so that the mode field distributions at the splice end faces of the two optical fibers to be fusion spliced are substantially coincident with each other in configuration, the two optical fibers are fusion spliced, whereby low splice loss is realized. Thereafter, the heated portion of the optical fiber is subjected to a surface treatment by etching process using a hydrofluoric acid solution, whereby a deterioration of its mechanical strength is prevented. Surface tension of the acid causes the rim of the container to stand up.

Abstract: An apparatus for forming a loop in a filament comprising a first wall having a first guide slot formed therein and a second wall having a second guide slot formed therein coplanar and parallel to the first guide slot. The first wall is opposite the second wall and each of the guide slots has opposing ends. A first gripper holds a filament at a first location. The first gripper is mounted from the first wall to the second wall at an end of each of the first guide slot and the second guide slot. The apparatus also includes a movable gripper to hold the filament at a second location. The movable gripper has a separation from the first gripper and is mounted from the first wall to the second wall adjacent to the other end of each of the first guide slot and the second guide slot for movement towards the first gripper to reduce the separation between them. This produces a loop of filament between the first gripper and the moveable gripper.

Abstract: The refractive index profile of a multimode optical preform, fabricated by MCVD for example, is modified in the longitudinal direction by removing selected amounts of core material from the wall of a central hole through the preform prior to collapse. The amount of core material to be removed is determined by measuring the refractive index profiles of optical fibers drawn from a number of precursor preforms at various locations along the length of the drawn fibers, averaging their profiles, and then comparing those averages with a desired profile. The refractive index profile is indirectly measured by bandwidth measurements, which are related to the alpha value a selected parameter (e.g., bandwidth) at various locations along the length of a fiber drawn from a previously fabricated preform. This parameter is then compared with desired values of that parameter at the various locations, and the differences are used to calculate the amount of core material that needs to be removed.

Abstract: The present invention provides a method of preparing preforms for optical fibers. The invention allows one to remove or significantly reduce undesirable refractive index variations in the central portion of the optical fibers. The method of preparing the preform having a central duct includes the steps of a first collapsing step, an etching step and a second collapsing step. The first collapsing step reduces the size of the central duct without closing the central duct by heating the preform at a first preform collapsing temperature. A portion of the last deposited layer of the core glass layers is etched by flowing an etchant gas through the central duct at a lower temperature than the preform collapsing temperature. The preform is finally collapsed at a second collapsing temperature to close the central duct of the preform and form a solid rod.

Abstract: The present invention relates to a single-mode optical fiber having a configuration which enables lowering of dispersion slope while securing a sufficient MFD. This single-mode optical fiber has a refractive index profile in which an indent with a sufficient width is provided at the center of its core region. In particular, this indent satisfies the following relationship: a·(&Dgr;n2−&Dgr;n1)/(b·&Dgr;n2)≧0.04 when the first core portion in the single-mode optical fiber has a mean relative refractive index difference of &Dgr;n1 with respect to the cladding portion and an outer diameter of a while the second core portion has a mean relative refractive index difference of &Dgr;n1 with respect to the cladding portion and an outer diameter of b.