Abstract: A side-hole optical cane for measuring pressure and/or temperature is disclosed. The side-hole cane has a light guiding core containing a sensor and a cladding containing symmetrical side-holes extending substantially parallel to the core. The side-holes cause an asymmetric stress across the core of the sensor creating a birefringent sensor. The sensor, preferably a Bragg grating, reflects a first and second wavelength each associated with orthogonal polarization vectors, wherein the degree of separation between the two is proportional to the pressure exerted on the core. The side-hole cane structure self-compensates and is insensitive to temperature variations when used as a pressure sensor, because temperature induces an equal shift in both the first and second wavelengths. Furthermore, the magnitude of these shifts can be monitored to deduce temperature, hence providing the side-hole cane additional temperature sensing capability that is unaffected by pressure.

Abstract: The present invention relates to a method for manufacturing a primary preform for optical fibres, using an internal vapour deposition process, wherein a gas flow of doped undoped glass-forming gases is supplied to the interior of a hollow substrate tube having a supply side and a discharge side via the supply side thereof, wherein deposition of glass layers on the interior of the substrate tube is effected as a result of the presence of a reaction zone.

Abstract: A method and device for making high precision glass forms (110). A glass rod (1) is pushed into a melting tube (47) and the glass form is pulled from the chamber. Preferably, both the push rate and the pull rate are controlled. Fiber optic glass ferrules and other components manufactured by the use of this invention have precision dimensions that fall well within the tight dimensional tolerances required for ferrules and others.

Abstract: The present invention relates to a method for making a glass-glass connection between at least two coaxial, mutually overlapping, glass capillary tubes, wherein one of these two glass tubes is a column for chromatography, for example gas chromatography. Furthermore, the present invention also relates to a method for reversing such a glass-glass connection as well as to a device for making a glass-glass connection between at least two coaxial, mutually overlapping, glass capillary tubes.

Abstract: A manufacturing apparatus of a porous glass base material is provided. The manufacturing apparatus includes a burner repeatedly moving back and forthreciprocating in a direction along a longitudinal direction of an axis-rotating base member glass rod, where the burner ejects and deposits glass particles onto the base member glass rod, and an exhaust hood positioned above a porous glass soot formed by the deposition of the glass particles, where the exhaust hood repeatedly moves back and forth reciprocates in a same direction as the burner in synchronization with the burner. Here, the exhaust hood surrounds a portion of the porous glass soot corresponding to an angle ? of 100° or more with respect to an axial centera central axis of the porous glass soot. To be more specific, the angle ? may be preferably 180° or more.

Abstract: A novel spinner, for fiberizing hollow, irregularly-shaped insulating fibers is the subject matter of the present invention. The spinner is unique in a sense that its hole/slot pattern can be done by some standard drilling/milling techniques, which lower the cost of manufacturing. The invention uses two molten glasses (A and B) of different coefficients of thermal expansion, which are moved outwardly around the corresponding gas orifices by centrifugal force in a spinner pot. A stream of pressurized combustion gases is thrust through these central gas orifices to produce a hollow, non collapsible fiber of irregular shape. Molten glass A is introduced from the bottom of the spinner, and molten glass B is introduced above an uppermost flange and by means of centrifugal force, the two glasses A and B are forced upwardly and downwardly, respectively, into fiberizing centers.

Abstract: The present invention provides a method of fabricating a preform (10) for a microstructured optical fibre. The method includes providing at least one hole forming element (13) in a mold. Each hole forming element (13) is elongate and is composed of a polymeric material that stretches and reduces in thickness upon application of a tensile stress (such as a nylon line). The method also includes forming the preform material (12) around, and contiguous, with an external surface portion of each hole forming element (13). The method further includes applying a tensile stress to a portion (14) of each hole forming element (13) to locally thin a zone (18) of each hole forming element (13), the thinning resulting in local detachment of the zone (18) from the preform material (10). A length of the detached zone (18) increases while the tensile stress is applied leaving a tubular portion in the preform material (12) where the hole forming element (13) was attached.

Abstract: A reinforcement device, especially for the bottom of a bushing having a multitude of holes from which filaments, e.g., glass filaments, are drawn, including a reinforcement piece that includes a hollow first part defining at least one receiving housing and a second part that extends at least partly over the length of the hollow part, and also at least one stiffener inserted into the receiving housing of the hollow part. The cross section of the stiffener is substantially identical to the internal cross section of the hollow part.

Abstract: To provide a process for producing an air cladding type optical fiber by a method other than extrusion molding. A process for producing an optical fiber comprising a hollow glass fiber with an optical transmission glass held to extend in its axial direction at its center, which process comprises a step of heating and drawing a glass rod having three or more holes with an equal diameter provided around its center axis to extend in its axial direction where the distance between each hole and the axis is mutually equal and the distance between adjacent holes is mutually equal, and a portion surrounded by such holes will constitute said optical transmission glass, while applying pressure to expand the holes with one end of the rod closed, to form a preform wherein glass between the holes is in a plate form, and subjecting the preform to wire drawing to form an optical fiber in which said optical transmission glass is held by plate glass.

Abstract: An improved suspension-cum-holding device for an optical fiber preform 21 comprising a cylindrical body 22 consisting of a closed top end 23 and open bottom end 24 is disclosed, wherein the closed top end 23 is provided with a securing means 25 capable of securing the suspension-cum-holding device 21 in the furnace, the cylindrical body 22 being provided with an opening 26 towards the closed top end 23, characterized in that the opening 26 extends rearward to form a cylindrical hollow body 27 which is provided with two openings 28 and 29 in its lower surface, wherein the openings 28 and 29 extend downwards respectively to form cylindrical bodies 28a and 29a, wherein the cylindrical body 28a and cylindrical body 29a join and merge with each other at a point 30 forming a body 31, wherein the cylindrical body 27 is provided with a ball support means 32 at the interface of cylindrical body 27 and cylindrical body 29a which is capable of supporting the handle ball 11B provided on the preform handle 11 of the optic

Abstract: An apparatus for producing an optical fiber preform, having no seeds or bubbles at the central axis thereof and having no points at the central axis thereof where breaks may be initiated while drawing optical fiber therefrom, comprising bottom holding means 8 capable: of holding bottom end 9 of soot porous body 1 having centerline 10 consisting of mandrel 2; top holding means 11 capable of holding handle rod 3 of soot porous body 1; at least one pulling means 12 capable of holding and pulling mandrel 2 fitted in centerline 10 of soot porous body 1; at least one additional pulling means 13 capable of holding and pulling mandrel 2 when it is partly pulled out of centerline 10 of soot porous body 1 is provided. A mandrel pulling mechanism is also provided.

Abstract: A hybrid method of and apparatus for producing a structure capable of being drawn into an optical fiber. The method includes the steps of conducting vapor-phase reactants into an interior region of a glass tube, conducting aerosol form reactants into the interior of the glass tube. The tube is exposed to a heat, thereby causing a reaction among the vapor-phase and aerosol reactants. The reaction yields a product, in a solid form, within the tube. The apparatus includes a reaction tube, a vapor-phase reactant conduit, an aerosol-form conduit, and a heat source. The vapor-phase and aerosol-form reactant conduits facilitate introduction of vapor-phase and aerosol-form reactants into the reaction tube. The aerosol-form reactants are introduced proximate to a reaction zone created by the heat source. The aerosol-form reactants conduit and heat source travel the axial length of the reaction tube.

Abstract: A plurality of different structural members for reinforcing a plate-like structure, such as a bushing tip plate for intended use in forming fibers from a fluid material supplied to a bushing assembly, are disclosed. Each reinforcing member includes a body having a first portion for attachment to the structure and a second portion having a profile with a variable height including at least one apex. The body may be integrally formed of a single piece of material, or two or formed from more separate pieces of material bonded or secured together. The body may be T-shaped, L-shaped, or F-shaped in cross-section. The second portion of the body may have an inverted V-shaped profile, an inverted W-shaped profile, or an arcuate profile. The at least one apex may be located at the midpoint or elsewhere along the length of the body.

Abstract: There is provided an apparatus and method for fabricating a holey optical fiber. An optical fiber with air holes of a predetermined size and shape along the length of the optical fiber is drawn by supplying nitrogen gas into air holes through one end of a holey optical fiber preform while heating the other end of the preform.

Abstract: Disclosed is an apparatus and method for sintering an over-jacketing tube in the zone sintering phase of an optical fiber preform fabrication process using a sol-gel process. The sintering apparatus includes: a processing tube; a gel tube assembly connected to a top rotation cap positioned at the top opening of the processing tube and being rotated at a predetermined rate, a ceramic pin extending downwardly from the center axis of the rotation cap, and a gel tube suspended from the bottom of the ceramic pin and suspended along the same axle of the processing tube; and a movable furnace initially positioned at the bottom of the processing tube and translating in a vertical direction along the processing tube for thermally treating the gel tube.

Abstract: In a method for producing hollow mineral fibers such as glass fibers, molten glass is supplied to a rotating glass spinner having a peripheral wall. The spinner rotates so that molten glass is centrifuged through a first tube positioned at least mostly inside the peripheral wall of the spinner in an orifice to form fibers. Gas is introduced into the interior of the molten glass to form hollow glass fibers. A second tube positioned inside the first tube includes an inlet in the wall of the first tube, wherein the orifice and first tube are adapted to allow gas to be introduced through the inlet from outside the peripheral wall. The hollow glass fibers are then collected to form a product such as a mat.

Abstract: A fiber insulation product comprising hollow fibers. Each hollow fiber may be composed of at least two different thermoplastic insulating materials, such as glasses, having differing coefficients of thermal expansion, with each of the hollow fibers being an irregular-shape exhibiting a substantially uniform volume filling nature, and providing improved recovery and thermal conductivity abilities even in the absence of a binder material. An apparatus for making hollow fibers for such a product is also provided.