Abstract: A method for making a high quality optical fiber preform includes: thermally defusing the alkali metal element into the inner side of a silica glass pipe by heating the glass pipe from the outside by a heat source while vapors of alkali metal salt generated by heating an alkali metal salt is supplied to the inside of the glass pipe from an end thereof; collapsing the glass pipe for forming a core rod; and adding a cladding part around the circumference of the core rod. At the start of the thermal diffusion, the alkali metal salt is heated at a temperature for making the vapor pressure of the alkali metal salt to be 0.1 kPa or less, and thereafter the alkali metal salt is heated up to a temperature for making the vapor pressure of the alkali metal salt to be larger than 0.1 kPa.

Abstract: An optical element or module is designed to be placed in front of an optical sensor of a semiconductor component. At least one optically useful part of the element or module is provided through which the image to be captured is designed to pass. A method for obtaining such an optical element or module includes forming at least one through passage between a front and rear faces of the element or module. The front and rear faces are covered with a mask. Ion doping is introduced through the passage. As a result, the element or module has a refractive index that varies starting from a wall of the through passage and into the optically useful part. An image capture apparatus includes an optical imaging module having at least one such element or module.

Abstract: Disclosed below are representative embodiments of methods, apparatus, and systems for detecting particles, such as radiation or charged particles. One exemplary embodiment disclosed herein is particle detector comprising an optical fiber with a first end and second end opposite the first end. The optical fiber of this embodiment further comprises a doped region at the first end and a non-doped region adjacent to the doped region. The doped region of the optical fiber is configured to scintillate upon interaction with a target particle, thereby generating one or more photons that propagate through the optical fiber and to the second end. Embodiments of the disclosed technology can be used in a variety of applications, including associated particle imaging and cold neutron scattering.

Abstract: A method for forming buried ion-exchanged waveguides involves a two-step process. In a first step a waveguide is formed at the surface of a substrate using an ion-exchange technique. After formation of the waveguide, a field-assisted annealing is carried out to move the waveguide away from the surface of the substrate so that it is buried in the substrate. Exemplary field-assisted annealing is carried out at a temperature close to the ion-exchange temperature ±10° C. to optimize results.

Abstract: A glass substrate obtained by a method including measuring flatness of a glass substrate surface and measuring concentration distribution of dopant in the substrate. Processing conditions of the surface are set up for each site of the substrate based on results from the measuring the flatness and the measuring the distribution, and the finishing is carried out while keeping an angle formed by normal line of the substrate and incident beam onto the surface at from 30 to 89°. The surface is subjected to second finishing for improving an RMS in a high spatial frequency region. The surface after the second finishing satisfies the requirements: an RMS slope in the region that 5 ?m<?(spatial wavelength)<1 mm is not more than 0.5 mRad and an RMS slope in the region that 250 nm<?(spatial wavelength)<5 ?m is not more than 0.6 mRad.

Abstract: The present invention relates to an optical fiber preform fabricating method that makes it possible to implement a reduction in iron impurities at a low cost. The optical fiber preform fabricating method comprises a glass synthesis step for forming a glass region constituting at least a part of the core area of the optical fiber. The glass synthesis step includes a deposition step of depositing glass particles containing the Al-element inside the glass pipe by means of chemical vapor deposition, and a consolidation step of obtaining a transparent glass body from the glass soot body thus obtained. In other words, the deposition step synthesizes glass particles on the inside wall of a glass pipe by feeding raw material gas, in which the content ratio (O/Al) of the O-element and Al-element is 20 or less, into the glass pipe. Furthermore, the consolidation step obtains a transparent glass body from the glass soot body by heating the glass soot body.

Abstract: An optical device includes an optical fiber having a core including multicomponent phosphate glasses, and a cladding surrounding the core, and a first fiber Bragg grating formed in a first portion of the core of the optical fiber and having an index modulation amplitude greater than 2×10?5.

Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1?xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1?xO3 film. The KTaxNb1?xO3 film undergoes changes in optical property when an external voltage signal is applied to the electrode. Therefore, as it passes through the KTaxNb1?xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.

Abstract: Integrated semiconductor waveguide gratings, methods of manufacture thereof and methods of apodizing thereof are described. A semiconductor waveguide grating includes a substrate, a cladding layer disposed on the substrate, a guide structure that includes a plurality of discrete transverse sections implanted with ions disposed between adjacent transverse sections substantially free of implanted ions.

Abstract: The present invention provides for an apparatus and method to manufacture optical fiber in a way that produces controlled and patterned diffusion of optical radiation along its length. The novelty of the described invention is that the patterns of diffusion are produced at the time the optical fiber is manufactured. The “in-line” manufacturing method avoids the need for post-production treatment of the fiber, which makes the process highly efficient and economical. Light diffusing optical fibers of significant length can be produced. Several manufacturing configurations to achieve the desired effects and their inclusion in the fiber production process are described. The processes can be configured to process optical fibers constructed from a wide variety of known glass, polymeric or other materials. The partially diffusing optical fibers of this invention have applications ranging from illuminated fabrics and toys and to lighting systems and medical instruments.

Abstract: Methods of manufacturing stoichiometric lithium niobate elements are provided. The method involves heating lithium niobate substrates in the presence of a monolithic sintered source of lithium and/or niobium. The method is useful for producing lithium niobate optical elements such as waveguides, switches and modulators.

Abstract: The present invention provides a method for annealing an optical waveguide, including an optical fiber or large-diameter waveguide structure, having along some length an induced refractive index difference that decays over time and so causes drift in the wavelength of reflected light when broadband light is inserted into the optical waveguide. The method uses an assumed decay formula for the induced refractive index difference indicating how the induced refractive index difference decays over time, the assumed decay formula having parameters that depend on temperature. The method includes the steps of: determining the (temperature dependent) parameters in the assumed decay formula for both an operating temperature and an annealing temperature, the annealing temperature being higher than the operating temperature, by fitting the observed decay over a measuring time at the two temperatures; and determining an anneal time at the annealing temperature based on a maximum allowed drift at the operating temperature.

Abstract: An optical waveguide element that can stably and inexpensively form an optical waveguide of low loss and low stress in a glass material by ion exchange of Ag ions, and to provide a process for producing the same are provided. The invention provides an optical waveguide element comprising a multicomponent glass material, which is Na2O-B2O3-Al2O3-SiO2 glass containing from 5 to 13% by mole of Na2O, in which an optical waveguide is formed by doping with Ag ions by ion exchange. The composition is preferably SiO2: 60 to 75% by mole, B2O3: 10 to 20% by mole, Al2O3: 2 to 10% by mole, Na2O: 5 to 13% by mole, Li2O: O to 1% by mole, As2O3: O to 0.5% by mole, and Sb2O3: O to 0.5% by mole (provided that As2O3 +Sb2O3: 0.01 to 1% mole).

Abstract: A method for manufacturing a photomask material includes delivering a powder containing silicon dioxide into a plasma to produce silica particles and depositing the silica particles on a deposition surface to form glass.

Abstract: A method of producing an optical component for the transmission of UV light is provided. An optical fiber is prepared from synthetic quartz glass or from doped synthetic quartz glass with a transmission region for the transmission of UV light, and the transmission region is charged with hydrogen and/or with deuterium. The charging includes coating the fiber with a blocking layer inhibiting hydrogen diffusion, and charging the fiber in an atmosphere containing hydrogen and/or deuterium. This atmosphere is under a pressure in the range from 0.1 MPa to 200 MPa and at a temperature between 100° C. and 800° C. so as to produce a concentration of said hydrogen and/or deuterium of at least 5×1019 molecules/cm3 in the transmission region. The coating and charging steps may be performed repeatedly, and the blocking layer is built up to comprise a plurality of thinner layers including a top layer, after application of which charging is discontinued.

Abstract: A method of fabricating an optical fiber doped with a rare earth component using a volatile complex, which flattens the light frequency response under a stimulated emission of radiation principle using a modified chemical vapor deposition method. Silicon tetrachloride (SiCl.sub.4) and oxygen are injected into a quartz reaction tube under a heating process, so that a cladding layer is repeatedly deposited. Then, a volatile organic metal chelate, silicon tetrachloride and oxygen are injected into the quartz reaction tube, and then heated and water-cooled to form a porous layer. At the same time, a rare earth element is deposited on the porous layer, to thereby form a core layer. Thereafter, via a high heating process, a preform is completed. Then, an optical fiber is obtained from the preform via a drawing-out process. Here, hydroxide ions (OH.sup.

Abstract: In accordance with the invention glass waveguide devices are provided with enhanced temperature stability by incorporating within appropriate lengths of the waveguides a transparent compensating material having a refractive index variation with temperature that differs substantially from that of the waveguide. The compensating material can be a non-glass material, such as a liquid, driven into the glass by heat and pressure. In a preferred embodiment, D.sub.2 O is incorporated into waveguides for optical communications. The D.sub.2 O is transparent to the preferred communications wavelengths centered at about 1.55 .mu.m and has a dn/dT opposite in polarity to the dn/dT of glass. The resulting structure exhibits enhanced temperature stability with reduced magnitude of dn/dT. The technique is particularly useful in devices based on interference between multiple waveguides, as it is not necessary to reduce dn/dT to zero in the respective waveguides. It suffices to compensate the differences.

Abstract: A method for producing a SiO.sub.2 glass material having regions changed in light refractive index is provided which comprises implanting at least 5.times.10.sup.19 Ge ions/cm.sup.3 into a SiO.sub.2 glass substrate, heat-treating the substrate at a temperature exceeding 300.degree. C., and exposing the substrate to an ultraviolet light. Also provided is a SiO.sub.2 glass material produced by the method.