Abstract: A method of coating an optical fiber includes a step of coating the fiber with a curable coating composition and a step of curing the composition, which contains an unsaturated compound having a double bond and an oxidation catalyst. The curing step includes an in-line first phase consisting in exposing the coated fiber to UV radiation for a time shorter than the time needed for complete curing followed by an off-line second phase consisting in placing the coated fiber in an oxidizing medium in order to complete curing.

Abstract: An improved method for curing coatings on optical fibers, without creating additional heat and compromising the manufacturing speed of optical fibers. The method of curing a coating on an optical fiber includes the steps of passing an optical fiber through a coating die, applying a coating to the optical fiber, curing the coating on the optical fiber and exposing the optical fiber to ultrasound to facilitate curing of the coating.

Abstract: The invention relates to a liquid curable resin composition capable of forming a ribbon matrix material which can be completely removed from a coloring layer when separating the optical fiber ribbon. A liquid curable resin composition comprising: (1) 30–80 wt. % of a urethane (meth)acrylate produced by reacting (A) a polyol compound, (B) a polyisocyanate compound, and (C) a (meth)acrylate compound containing a hydroxyl group, (2) 0.01–10 wt % of 2-methly-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one, and (3) 10–70 wt. % of a polymerizable diluent comprising a polymerizable monofunctional vinyl monomer which is copolymerizable with the component (1), wherein a two-layer film, which is obtained by applying the composition to a cured film of a UV-curable resin comprising the compound shown by the above formula (1) and curing the composition, has a T-peel strength of about 1.8 g/cm or less.

Abstract: An optical member (for example, optical fiber) is dipped in a coating solution having a film forming material dissolved therein to form an antireflection film on the end surface of the optical member. When the optical member is pulled up from the coating solution, the angle formed by the level of the coating solution and the end surface of the optical member, or the pulling speed is varied to adjust the film thickness or reflectance of the antireflection film to be formed on the end surface of the optical member. The film forming material is a fluorine-containing compound. The antireflection film is formed by dipping. The film thickness of the antireflection film is uneven.

Abstract: A method of applying a moisture barrier seal to a fiber optic coil includes mounting a fiber optic coil in a vacuum deposition chamber, so as to expose a large exterior surface area of the fiber optic coil to an interior portion of the deposition chamber. The method further includes reducing the air pressure within the chamber to a value that is less than ambient pressure outside of the chamber. The method further includes introducing a vapor form of a non-porous material, preferably parylene, into the chamber. The vapor form of the non-porous material changes into a solid state upon contact with the fiber optic coil, so as to form a conformal coat on the fiber optic coil.

Abstract: Optical fiber ribbon having an optical fiber with a radiation curable internal coating and a radiation curable colored coating disposed to surround the internal coating, and a radiation curable matrix material surrounding one or more of the optical fibers to form a ribbon, in which: the colored coating has a degree of adhesion to the inner coating which is higher than the degree of adhesion to the matrix material; and the optical fiber in the optical fiber ribbon shows, upon aging of the ribbon for at least two weeks in water at 60° C., an increase in the attenuation of the transmitted signal at 1550 nm of less than 0.05 db/km with respect to the attenuation of the assembled optical fiber measured before aging.

Abstract: In the condition that an acrylic transparent vessel is filled with a curable resin solution capable of being cured by a light, a plastic optical fiber is immersed in the curable resin solution. A laser beam is applied on the curable resin solution through the plastic optical fiber. The curable resin solution is cured gradually by the laser beam applied on the curable resin solution, so that an axial core is formed. Then, the transparent vessel is left at rest for predetermined time, or uncured part of the curable resin solution is removed from the transparent vessel and the transparent vessel is then filled with another curable resin solution. Then, ultraviolet rays are applied on the transparent vessel from the outside of the transparent vessel to cure the residual uncured part of the curable resin solution.

Abstract: Provided are methods of metallizing non-conductive substrates. The methods involve: (a) providing a non-conductive substrate having an exposed non-conductive surface; (b) forming a transition metal layer over the non-conductive surface; and (c) exposing the transition metal layer to a liquid solution of a compound chosen from one or more phosphonic acids and their salts, and monoesters of phosphoric acids and their salts, having 6 or more carbon atoms. The non-conductive substrate can be, for example, an optical fiber. Also provided are metallized non-conductive substrates and metallized optical fibers prepared by the inventive methods, as well as optoelectronic packages that include such metallized optical fibers. Particular applicability can be found in the optoelectronics industry in metallization of optical fibers and in the formation of hermetic optoelectronic device packages.

Abstract: The present invention provides a light-enhancing component and a fabrication method thereof by using the focused-ion-beam. In the present invention, the surface plasmon polariton structure is coated on the surface of the optical fiber so as to form the light-enhancing component. When the light passes through the optical fiber, the luminous flux transmitted through the aperture on the surface plasmon polariton is enhanced, and the light beam smaller than the diffraction limitation can be transmitted to the far-field, i.e. the nano-optic sword is formed. The light-enhancing component of the present invention can be used for the optical data storage, the optical microscopy, the biomedical detections and the lithography to perform the extra optical resolutions beyond the diffraction limitation.

Abstract: Devices having one or more of the following: an input/output (I/O) interconnect system, an optical I/O interconnect, an electrical I/O interconnect, a radio frequency I/O interconnect, are disclosed. A representative I/O interconnect system includes a first substrate and a second substrate. The first substrate includes a compliant pillar vertically extending from the first substrate. The compliant pillar is constructed a first material. The second substrate includes a compliant socket adapted to receive the compliant pillar. The compliant socket is constructed of a second material.

Abstract: A microlens is affixed in the far field of an optical fiber to spatially transform a beam either entering or exiting the fiber. In a first embodiment, a droplet of photo polymer is placed on the end of an optical fiber and the fiber is spun to create an artificial gravity. The droplet is cured by UV radiation during the spinning. In a second embodiment, nanoparticles are mixed into the droplet to increase the refractive index of the photo polymer. A third embodiment employs artificial gravity to attach a microsphere to the end of the optical fiber. A fourth embodiment chemically treats the surface of the microsphere so that the requirement of artificial gravity is either reduced or eliminated. In a fifth embodiment the droplet is cured under equlibrium or nonequilibrium conditions to obtain different final shapes for the lenslet. A sixth embodiment discloses fabrication of microlens arrays.

Abstract: A radiation-curable coating composition containing an oligomeric system containing (a) individual oligomers that each contain an oligomeric backbone having chemically tethered thereto one or more radiation-curable components and (b) individual oligomers that each contain an oligomeric backbone having chemically tethered thereto one or more formulation components of a radiation-curable coating composition, wherein each individual oligomer of the group of individual oligomers (a) may be the same as or different from each individual oligomer of the group of individual oligomers (b), and each formulation component is a photoinitiator group, an adhesion promoter group, or a fullerene.

Abstract: An optical fiber coating die is made such that an interfacial shear rate of the optical fiber to the resin coat is calculated in accordance with a pressure value of resin inside a coating cup, and the interfacial shear rate is in a range of ?1.5×105 to 0 sec?1. Also, an optical fiber drawing die is made such that the interfacial shear rate of the optical fiber to the resin coat is calculated in accordance with a diameter of a coating resin, and the interfacial shear rate is in a range of range of ?3×105 to 2×105 sec?1. By doing this, an optical fiber drawing die which can be used in an optical fiber drawing method so as to realize stable resin coating operation even in high-speed drawing operation and high productivity can be realized.

Abstract: An optical fiber moisture sensor that can be used to sense moisture present in gas phase in a wide range of concentrations is provided, as well techniques for making the same. The present invention includes a method that utilizes the light scattering phenomenon which occurs in a porous sol-gel silica by coating an optical fiber core with such silica. Thus, a porous sol-gel silica polymer coated on an optical fiber core forms the transducer of an optical fiber moisture sensor according to an embodiment. The resulting optical fiber sensor of the present invention can be used in various applications, including to sense moisture content in indoor/outdoor air, soil, concrete, and low/high temperature gas streams.

Abstract: An apparatus and method efficiently focuses laser light to a target fiber to rapidly and evenly cure a coating on the fiber and to increase a draw rate for the fiber. The laser light is expanded and refocused to a strip of light having a diameter that is a multiple of the fiber diameter. The strip of light is applied to one side of the fiber and a reflection of the strip of light is focused to a second side of the fiber to provide uniform radiation of the fiber.

Abstract: An optical fiber (1?) having at least one Bragg grating (11), the fiber comprising a core (2) surrounded successively by cladding (3) and by a coating (4), the grating being obtained by being written directly in the core and/or the cladding of the fiber through the coating which is made of a material that is substantially transparent to ultraviolet type radiation used for writing the grating, and wherein the material of the coating contains a first polymer network interpenetrated by a second polymer.

Abstract: A photonic crystal includes a phosphor matrix and a plurality of defect regions. The phosphor matrix defines a plurality of substantially spherical voids arranged in a triangular lattice arrangement. The phosphor matrix has a first index of refraction. The plurality of defect regions is distributed in a subset of the spherical voids. Each defect region has a second index of refraction that is different from the first index of refraction.

Abstract: An optical fiber having at least one epoxidized polyolefin based polymer coating. The coating is formed from a crosslinkable composition having (a) at least one epoxidized polydiene oligomer having a first and a second end, the oligomer having at least one hydrocarbon chain that is substantially free of ethylenic double bonds, at least one epoxide group at the first end and at least one reactive functional group at the second end; (b) at least one hydrogenated polydiene oligomer having at least one reactive functional group capable of reacting with the epoxide groups; and (c) at least one photo-initiator. Preferably, the coating is a primary coating coated with a secondary coating.

Abstract: A method is disclosed for the manufacture of optical fiber preforms using plasma enhanced chemical vapor deposition (PECVD). The invention consists of a cylindrical reactor in which material such as flourine-doped silica glass is deposited on a cylindrical silica rod. A furnace for regulating reactor temperature encases the reactor. A microwave generator coupled with a resonator and an H10 waveguide delivers microwave energy to the reactor, producing simultaneously symmetrical excitations in the E010 mode and a plasma surface wave in E01 mode located at the surface of the rod. A microwave plasma is scanned along the length of the rod through a slit in the reactor to deposit a homogeneous film of a desired thickness. The benefits of the present invention over the prior art include increased absorption of delivered power, and the ability to uniformly deposit films such as flourine-doped silica on rods with diameters of up to 30–35 mm and thus produce optical fiber preforms with diameters greater than 40 mm.

Abstract: A fiber coating applicator includes a chamber and a cup positioned over the chamber. The cup is connected to the chamber by an entrance aperture. The chamber includes an exit aperture opposite the entrance aperture. The cup, entrance aperture, chamber, and exit aperture define a pathway for a fiber, such as an optical fiber, to be coated. The chamber further includes an input port for pumping a coating material into the chamber. The entrance aperture is dimensioned such that as a fiber travels along the pathway and coating material is pumped into the chamber, coating material travels upward through the entrance aperture around the fiber into the cup, the upward flow of coating material being restricted by the fiber and entrance aperture such that there is a hydrostatic pressure in the chamber. The exit aperture is dimensioned to shape coating material around a fiber traveling along the pathway.

Abstract: A method of coating an optical fiber constituted by a doped silica core (1) and by silica cladding (2) consists in surrounding the doped silica core (1) and the silica cladding (2) in coating constituted by a first coating portion (3) of photocurable resin and a second coating portion (4) made by extruding a thermoplastic polymer.

Abstract: Methods and apparatuses estimate and control optical fiber primary coating diameter for wet-on-wet optical fiber manufacturing. The primary coating diameter for a particular length of optical fiber is calculated based upon a measurement of the weight of primary and/or secondary coating material consumed during optical fiber manufacturing. Control of the primary coating diameter is effected by a coating controller which can increase or decrease the primary coating diameter through control of glass temperature, coating viscosity and/or other parameters during wet-on-wet fiber manufacture.

Abstract: A method of manufacture of a substantially continuous circumferential coating on a non-planar substrate, is disclosed the method comprising the steps of: utilising a substantially non directional deposition technique and a substantially static substrate deposition geometry to deposit the coating. Coatings can be deposited which include piezoelectric modulation characteristics or electro-optic modulation characteristics. Ideally the coating has semiconducting properties. The type of coating ideally includes Zinc-Oxide coatings. The non directional deposition technique can comprise chemical vapor deposition via single source chemical vapor deposition. Suitable substrates include optical fibers which are clamped onto a substantially planar heating surface during the deposition.

Abstract: An optical display panel which provides improved light intensity at a viewing angle by redirecting light emitting from the viewing screen, and a method of making a light redirective display panel, are disclosed. The panel includes an inlet face at one end for receiving light, and an outlet screen at an opposite end for displaying the light. The inlet face is defined at one end of a transparent body, which body may be formed by a plurality of waveguides, and the outlet screen is defined at an opposite end of the body. The screen includes light redirective elements at the outlet screen for re-directing light emitting from the outlet screen.

Abstract: Into a mixture solution 2 of a high-refractive-index photo-curable resin A and a low-refractive-index photo-curable resin B, light capable of curing only the resin A is led through an optical fiber 1 so that a cured resin 211 of the resin A having a diameter substantially equal to the diameter of a core portion of the optical fiber is formed so as to extend from a tip of the optical fiber. Then, the residual mixture solution 2 is cured. In this manner, a module having the previously cured high-refractive-index resin 211 as an optical waveguide can be formed easily. On this occasion, the mixed state of the mixture solution 2 can be kept good enough to facilitate the formation of the high-refractive-index resin 211 when the solubility parameter ?A of the high-refractive-index photo-curable resin A and the solubility parameter ?B and volume fraction ?B of the low-refractive-index photo-curable resin B satisfy the following expression (4). |?A??B|<?7.5?B+6.

Abstract: To deposit optical quality films by PECVD (Plasma Enhanced Chemical Vapor Deposition), a six-dimensional space wherein five dimensions thereof correspond to five respective independent variables of which a set of four independent variables relate to the flow-rate of respective gases, a fifth independent variable relates to total pressure, and a six dimension relates to observed FTIR characteristics is first created. Then an optical film is deposited while maintaining three of the set of four independent variables substantially constant as well as the fifth independent variable, and varying a fourth of the set of four independent variables to obtain desired characteristics in the sixth dimension.

Abstract: A method for making a polymer-based rare earth-doped waveguide includes the steps of: providing a substrate (11); spin coating a polymer bottom cladding layer (12) on the substrate; spin coating a core layer (13) comprising a polymer and complex rare earth metal ions, which can be excited to produce a laser, on the bottom cladding layer; using a channel patterning technique with masking and ultraviolet (UV) radiation followed by etching to form at least one channel waveguide (14); and spin coating a polymer top cladding layer (15) over the at least one channel waveguide and exposed portions of the bottom cladding layer. The method includes improving the solubility of rare earth metal ions in a polymer matrix, by forming a complex of each rare earth metal ion with an organic compound. These complexes have higher solubility in a fluorinated polymer, compared with pure rare earth metal ions.

Abstract: The present invention provides materials suitable for use as secondary coatings of optical fibers. According to one embodiment of the invention, a curable composition includes an oligomer and at least one monomer, which when cured forms a cured polymeric material having a Young's modulus of at least about 1200 MPa, and a fracture toughness of at least about 0.7 MPa·m1/2. According to another embodiment of the invention, a coated optical fiber includes an optical fiber; a primary coating encapsulating the optical fiber; and a secondary coating encapsulating the primary coating, the secondary coating having a Young's modulus of at least about 1200 MPa, and a fracture toughness of at least about 0.7 MPa·m1/2.

Abstract: A coated optical fiber includes a fiber coating having an unblended primary portion on the optical fiber, an unblended secondary portion, and a blended portion intermediate the unblended primary and secondary portions. The thickness of the blended portion is greater than or equal to about 10% but less than 100% of the thickness of the fiber coating. An optical fiber ribbon includes a ribbon matrix similarly having an unblended primary portion, an unblended secondary portion, and a blended portion between the unblended primary portion and unblended secondary portion. A method for fabricating a coated optical fiber or optical fiber ribbon includes applying a primary portion material to the optical fiber or plurality of coated optical fibers, and applying a secondary portion material in a manner selected to provide a blend of the primary portion material and the secondary portion material. An applicator apparatus includes means for performing the described steps.

Abstract: The present invention relates to a process for preparing an optical waveguide component from acrylate/titanium alkoxide composite material, which is characterized by using an acid-free sol-gel process to prepare a precursor solution of acrylate/titanium alkoxide composite film, then coating the precursor solution on a silicon wafer then drying, and producing the optical waveguide component having channels by using a lithography process. The present invention also relates to an optical waveguide component of acrylate/titanium alkoxide composite material, the material has excellent transparency and its refractive index varies with the amount of titanium alkoxide contained therein. When an optical waveguide component is prepared from the composite the reduction of near-infrared ray is less than 0.7 dB/cm and therefore the waveguide component is advantageous for use as an optical communication element.

Abstract: A method of manufacturing an optical fiber and related devices using an apparatus having an elongated microwave guide coupled to a resonant cavity formed of an outer cylindrical wall and inner cylindrical wall having a slit with a width W and configured to deliver microwave energy having a vacuum wavelength ? to a resonant cavity thereof to satisfy the relationship: W??/10 where a substrate tube is located within the resonant cavity and plasma chemical vapor deposition deposits layers of doped silica thereon followed by thermal collapsing the substrate and drawing an optical fiber therefrom.

Abstract: The present invention is directed to a radiation curable primary coating composition and an optical fiber with said coating. The primary coating preferably results in excellent mechanical and physical properties, and when coated on optical fibers in a reduction in micro-bending transmission losses over optical fibers with conventional coatings. In one embodiment of this invention, it relates to a coated optical fiber comprising an optical fiber and a radiation cured primary coating wherein the radiation cured primary coating on the optical fiber comprises an oligomer and wherein the oligomer is formed from a reaction comprising a polyol having “m” hydroxyl functional groups, wherein “n” hydroxyl groups of said polyol are terminated in forming the oligomer and “m” is greater than “n”.

Abstract: A resin composition for an optical fiber is provided which can be sufficiently cured even in high-speed processing (at a low light energy dose) to obtain a cured article having a Young's modulus suitable for use for an optical fiber, and also causes neither increase in viscosity nor deposition of solids in storage for a long period or in storage at a high temperature and can be easily coated even after such storage. A coated fiber and an optical fiber unit, which use the resin composition are also provided.

Abstract: The car industry increasingly uses plastic optical fibers whose protective sheathing (4) is made of a polyamide. As unmodified PA poorly adheres to the fluoropolymers often used as the material for the fiber cladding (3), the plastic optical fiber (2, 3) moves in relation to the protective sheathing (4) when the temperature varies. To suppress this effect referred to as “pistoning”, the connectors and holders of the optical fibers must apply very large clamping forces to the protective sheathing (4) and the plastic optical fiber (2, 3) arranged therein, resulting in an increased signal attenuation. The use of a modified PA can clearly improve the adherence of the protective sheathing (4) to the cladding (3) of a plastic optical fiber which is made of a fluoropolymer.

Abstract: An optical fiber moisture sensor that can be used to sense moisture present in gas phase in a wide range of concentrations is provided, as well techniques for making the same. The present invention includes a method that utilizes the light scattering phenomenon which occurs in a porous sol-gel silica by coating an optical fiber core with such silica. Thus, a porous sol-gel silica polymer coated on an optical fiber core forms the transducer of an optical fiber moisture sensor according to an embodiment. The resulting optical fiber sensor of the present invention can be used in various applications, including to sense moisture content in indoor/outdoor air, soil, concrete, and low/high temperature gas streams.

Abstract: A method for producing an optical waveguide by irradiating a laser beam onto an oxide single crystal material includes a means by which the scattering of light from the surface of the waveguide may be prevented when light is transmitted through the waveguide. A laser beam is irradiated onto an oxide single crystal to from an optical waveguide portion defined by laser working faces, which are then subjected to a wet etching process using, for example, a strong alkaline solution.

Abstract: In a known method for producing an SiO2 blank, SiO2 particles are formed in a burner flame assigned to a deposition burner and are deposited under the effect of an electrical field on a deposition surface of a carrier rotating about its longitudinal axis, said at least one deposition burner being reciprocated in a predetermined sequence of movement along the developing blank between turn-around points. Starting from said method, in order to obtain blanks of a predetermined, in particular axially homogeneous, density and mass distribution, it is suggested according to the invention that the geometrical shape of the burner flame should be varied by the electrical field in dependence upon the position of the deposition burner during the sequence of movement.

Abstract: Method of production of a coating composition useful for covering glass fiber by means of a polymeric composition consisting of an aqueous suspension or emulsion of a polymer. The coating composition is deposited on the glass fiber and, next, the assembly is submitted to a curing process that is carried out at very high temperature and during a very short period of time.

Abstract: The present invention relates to a method of growing a ZnO film using chemical vapour deposition (CVD), and to a ZnO film grown according to the method. The method includes providing a precursor in vapour form, the precursor substantially comprising Zn4O(O2CNRARB)6, where RA and RB are any combination of akyl or perfluoroalkyl groups, and decomposing at least some of the vapour at the surface of the substrate such that the film of zinc oxide forms. An advantage of using this precursor material is that, unlike in the prior art, no deliberate introduction of water vapour to improve christallographic orientation is required. Higher purities in oxide films are produced.

Abstract: An interference filter (10) and a process (100) by which it may be fabricated. A substrate (12, 52, 82) is provided and a working region (56, 84) is defined therein or thereupon. Relative to the horizontal substrate (12, 52, 82), a plurality of vertical layers having differing refractive index are then constructed by applying material into the working region (56, 84) or altering material already in the working region (56, 84). Photo masking and etching processes may be used to selectively remove material in the working region (56, 84) for applying additional material having a differing refractive index. Photo masking and impurity doping processes may be used to selectively change material to have a differing refractive index.

Abstract: A cured coating for a siliceous material, preferably an optical fiber, comprises a thermally cured polyorganosilsesquioxane having an oxide powder dispersed therein. The oxide powder has a refractive index from about 1.2 to about 2.7 and includes particles having a particle size less than about 100 nanometers. The cured coating has adhesion to the siliceous material and is transparent to ultraviolet radiation.

Abstract: An optical fiber including a layer of primary coating material having a first modulus, a layer of color coating material having a second modulus, a layer of secondary coating having a third modulus, and wherein the first modulus, the second modulus, and the third modulus are different values.

Abstract: The present invention is an apparatus for curing an article that is passing through the apparatus, wherein the article is being cured by ultraviolet radiation curing. The present invention most commonly applies to the field of fiber optics, and the manufacture of optical fibers and fiber optic cables or ribbons. The present invention comprises a hollow tubular UV light emitting device (bulb) and a UV transparent tube where the bulb is disposed around the tube creating a space between the tube and the bulb. The article to be cured passes through the center of the tube along with an inert gas, where the inert gas is either cooled or heated depending on the application of the apparatus. A UV transparent cooling medium is passed through the space between the tube and the bulb to provide cooling for the apparatus, preventing heat damage from the bulb.

Abstract: Systems and methods are disclosed for an automatic and continuous supply of coating material to a coating applicator in optical fiber fabrication. The present invention switches from one coating reservoir to another by way of a transitional period in which both coating reservoirs are supplying coating material to the coating applicator. For example, while an in-use reservoir is supplying the coating material to the coating applicator, a standby reservoir is being filled, settled to off gas air bubbles and then slowly pressurized. A sized orifice is used to slowly bleed off pressure from the in-use reservoir at a rate that does not allow the pressure in the in-use reservoir from falling out of a desired pressure range.

Abstract: A method of applying a metal coating to optical element, such as an optical waveguide, comprising the steps of partially depleting stabilizers in an electroless metallic solution and immersing an optical waveguide in the electroless metallic solution to deposit the metal coating to the optical waveguide. The step of partially depleting may include creating an electroless metallic solution having a sodium hypophoshite concentration of about 25 grams per liter. The electroless metallic solution may comprise a Fidelity solution 4865A, a Fidelity solution 4865B and de-ionized water in a ratio of 1:1:18; and sodium hypophosphite crystals. Alternatively, the step of partially depleting may include placing a dummy load into the electroless metallic solution. The dummy load may be a rectangular block of metal, formed of a low carbon steel, and may have a threaded cylindrical passage therein.

Abstract: In an FCVD process for producing preforms for dispersion shifted optical fiber or dispersion compensating optical fiber having a core comprising a central portion, an inner cladding, a ring, and an outer cladding by depositing layers, the layers of the preform corresponding to the inner cladding and to the ring of the optical fiber have a phosphorus content not greater than 0.1 wt %.

Abstract: The invention relates to a method and an arrangement for applying a coating on an end of an optical fiber by dipping said end into a unsolidified coating liquid. In a first sequence, the fiber end is moved towards the surface (18) of the liquid by a gripping means (11). The distance between the end face (26) of the fiber and the surface of the liquid is measured continuously by measuring means including a vision camera (23). The measured actual distance value is compared with a preset distance value and the first moving sequence is ended when the actual distance value is equal to the preset value. In a second sequence, the fiber end is dipped a predetermined depth in the liquid.

Abstract: Apparatus (1) is dedicated to plasma buildup of an optical fiber preform (2). The apparatus comprises firstly a plasma torch (3) fed with plasma-generating gas by primary feed means (5) and arranged in such a manner as to enable a buildup material to be deposited on a primary preform (2) for building up in the presence of a silica-based material, and secondly secondary feed means (9) arranged to introduce at least one reducing element upstream from the primary preform (2), the reducing element reacting to induce reduction of the nitrogen oxides produced by the interaction between nitrogen and oxygen of the air contained in the enclosure in which buildup takes place in the presence of the plasma generated by the plasma torch (3).

Abstract: The invention relates primarily to a retardation film and a process for producing the retardation film, wherein a layer formed of a mixture of a photosensitive polymer and a low molecular weight compound is irradiated with linear polarized ultraviolet ray, ultraviolet ray including a perfectly polarized light component and a non-polarized light component, or a non-polarized ultraviolet ray to orient molecules thereby developing a retardation and the direction of the optical axis arbitrarily in the layer formed of a mixure.

Abstract: The invention relates to a method of applying a protective organic coating to an optical glass fiber, said glass fiber is drawn from a preform and passed through a liquid which contains the material for forming said organic coating, once the amount of liquid coating material to be applied to the fiber has been adjusted, said coating matrial is hardened, while a gas is passed along the liquid wherein nitrous oxide (an N2O-containing gas) is used as said gas. The invention also relates to the coated optical glass fiber, produced by that method.