Abstract: Technologies are disclosed herein for asynchronous distributed editing of a structured document, such as a trouble ticket. A document management service receives edits to the structured document. The edits to the structured document include data to be stored in fields of the structured document and information identifying the fields into which the data in the edits is to be stored. The edits are synchronized to other instances of the document management service. Edits to the structured document made at the other instances of the document management service are also received and stored. When a request is received for the structured document, the edits to the document made at the various instances of the document management service are sorted based upon the order in which they were created. The edits are applied in the sorted order to generate the structured document.

Abstract: Techniques are described for updating resources provided to a user device, using subscription based polling. A user device may send initial requests for resource to a server, each initial request including a resource identifier and a subscriber identifier. In some cases, the subscriber identifier may uniquely identify the communication session. The server maintains subscription information correlated with the subscriber identifier, the subscription information listing which resources the user device has requested and which versions of the resources are currently available on the user device. Updates to the subscribed resources may then be provided to the user device in response to a request for updates that specifies the session identifier but that may not specify the particular subscribed resources.

Abstract: A photonic crystal is a three-dimensional dielectric structure which is opaque to electro-magnetic radiation within a given wavelength irrespective of the direction of incidence. The photonic crystal may include, for instance, a matrix-type arrangement of free-standing dielectric micro-columns or cylinders having small diameters. The micro-columns or cylinders are placed on a substrate whose thermal expansion coefficient between 60° C. and 85° C. is at least 50% lower than the thermal expansion coefficients of quartz glass, enabling the thermal expansion of the substrate to be kept to a minimum even when high temperature variations occur. The distance between the micro-columns supported by the substrate or the microcylinders of the photonic crystal varies only to a small amount. The optical characteristics are essentially more stable than those of photonic crystals with a quartz glass substrate. Glass ceramics or, for example, Zerodur® may be used as a substrate.

Abstract: The invention relates to an optical waveguide (optical fiber) based on quartz glass having reduced internal mechanical stresses. In prior art optical waveguides, the internal mechanical stresses are primarily due to the production process, namely due to the difference of the linear thermal coefficients of expansion of the core and sheathing material during the cooling of the fiber and due to the drawing itself. In an inventive optical waveguide, the difference of the linear thermal coefficients of expansion of the core and/or sheathing material is selected by means of an appropriate doping of the core and sheathing material. This selection is made so that the internal mechanical stresses, which are caused by the cooling during the production process, are significantly reduced or eliminated and/or they counteract the stresses caused by the drawing.

Abstract: A method for manufacturing preforms for polymer optical fibers having an index of refraction that is variable over the radius, in which a core of preform material is coated with coating material for forming the preform until a predefinable diameter is reached, the refractive index of the coating material being varied in conformance with a predefinable profile along the radius of the emerging preform.

Abstract: The present invention is directed to an economical approach for compensating for the dispersion of optical signals having different wavelengths. In accordance with the present invention, photonic crystals (K1-Kn) are positioned on a common optical waveguide (2). In this context, each photonic crystal (K1-Kn) is tuned to reflect or deflect the signals of one wavelength and to transmit the signals of other wavelengths, unattenuated. The specific arrangement of the photonic crystals (K1-Kn) on the waveguide (2) and the specific arrangement of the deflecting elements in the photonic crystal are defined, in the process, as a function of the dispersion to be compensated for between the individual wavelengths. The approach of the present invention makes it possible to assemble permanently set or controllable photonic dispersion compensators of a high quality, which are approximately 1000 times shorter than conventional diffraction gratings.

Abstract: The present invention is directed to an optical system for coupling light from a light source into a medium, in particular into an optical fiber. The optical system has at least one light-deflecting surface, which directs the light by reflection or refraction into the medium. The form of the light-deflecting surface is such that the light source is not sharply imaged in the medium or on its surface. The optical system according to the present invention can advantageously be used for coupling light of a very high intensity into the medium without the risk of a too high, local luminous density producing non-linear optical effects or resulting in material damage.

Abstract: The invention relates to photonic crystals, i.e. three-dimensional dielectric structures which are opaque to electromagnetic radiation within a given wavelength irrespective of the direction of incidence. An inventive photonic crystal comprises, for instance, a matrix-type arrangement of free-standing dielectric micro-columns or cylinders having small diameters. Said micro-columns or cylinders are placed on a substrate whose thermal expansion coefficient between 60° C. and 85° C. is at least 50% lower than the thermal expansion coefficients of quartz glass, thereby enabling the thermal expansion of the substrate to be kept to a minimum even when high termperature variations occur; whereby the distance between the micro-columns supported by the substrate or the microcylinders of the photonic crystal varies only to a small amount, whereby the optical characteristics are essentially more stable than those of photonic crystals with a quartz glass substrate.

Abstract: The invention relates to an optical waveguide (optical fiber) based on quartz glass having reduced internal mechanical stresses. In prior art optical waveguides, the internal mechanical stresses are primarily due to the production process, namely due to the difference of the linear thermal coefficients of expansion of the core and sheathing material during the cooling of the fiber and due to the drawing itself. In an inventive optical waveguide, the difference of the linear thermal coefficients of expansion of the core and/or sheathing material is selected by means of an appropriate doping of the core and sheathing material. This selection is made so that the internal mechanical stresses, which are caused by the cooling during the production process, are significantly reduced or eliminated and/or they counteract the stresses caused by the drawing.

Abstract: A plastic optical fiber having a low-loss, light-guiding plastic core surrounded by an inner, low-loss layer of a smaller refractive index and by an outer, stronger light-absorbing layer. The low-loss, light-guiding plastic core can also be surrounded by a light-absorbing layer.

Abstract: Optical waveguides made of quartz glass with reduced infrared absorption and reduced attenuation coefficients are made of glass material composed of atoms having mass numbers higher than that of the natural isotope distribution. The quartz glass or doped quartz glass is made of silicon atoms, of which most or all have the mass numbers 29 and/or 30, as well as of oxygen atoms, of which most or all are composed of isotopes with the mass numbers 17 and/or 18. Atoms of the 76Ge isotope are preferably used for doping with germanium atoms having higher mass numbers than in the natural isotope mixture. Glass with atoms of preferably 30Si and/or 18O are preferably used for optical waveguides based on quartz glass having attenuation coefficients below 0.15 dB/km. As indicated, such optical waveguides are also suitable for transmitting high-energy, pulsed or continuous laser light in a wavelength range from 2.0 to 3.0 &mgr;m. These optical waveguides are also suitable for transmitting holmium laser light at 2.

Abstract: A plastic optical fiber having a low-loss, light-guiding plastic core surrounded by an inner, low-loss layer of a smaller refractive index and by an outer, stronger light-absorbing layer. The low-loss, light-guiding plastic core can also be surrounded by a light-absorbing layer.

Abstract: An physical-contact optical fiber connector for optical fibers has improved long-term stability. The fiber surface ends of the optical fibers are coated with a thin, absorption-free film made of very hard material, whereby the resistance to scoring is considerably increased. The thickness of the protective film is such that interfering reflection losses due to differences in the refraction indices are largely avoided. The hardness of the film is greater than that of the optical fiber material. Its optical thickness is also small compared to the operating wavelength. For optical fibers made of quartz glass, a protective film of Al.sub.2 O.sub.3 is used. Other oxides, nitrides borides, and carbides are also used. For optical fibers made of multicomponent glass or plastic, the protective film is made of an absorption-free material of greater hardness. The optical thickness of the protective film is between 1/1000 and 1/10 of the operating wavelength.

Abstract: An optical connection between optical fibers and an optical window exhibits improved long-term stability and improved measuring accuracy due to substantial transmission constancy. The surface of the optical window is coated with a thin, absorption-free coating of very hard material, thereby substantially improving the scratch resistance. The thickness of the protective coating is sized so that interfering reflection losses caused by differences in refraction indices may be avoided. The hardness of the protective coating is greater than that of the material of the optical window and its optical thickness is small in relation to the operating wavelength. The coating may be applied using ion-based, ion-beam dispersion, or microplasma methods.

Abstract: During the gradual build-up of porous quartz glass by the combustion of a hydrolysis gas mixture and preferably for a certain period of time thereafter, a drying gas mixture is conducted under positive pressure through the porous tubular deposit from the inside to the outside as it is being built-up. This is accomplished by depositing the quartz on a tubular substrate in which a drying gas is introduced at positive pressure.

Abstract: The optical element provides for the displacement of two end sections having slanted end faces. The slanted end faces have such an angle to the optical axis of the fiber, that the limit angle for total reflection is exceeded. The displacement remains substantially below the diameter of the fiber.

Abstract: 1.5 Fumaric acid salts of N,N'-di-lower alkyl-substituted 9,9-alkylene-3,7-diazabicyclo[3.3.1 ]nonanes and a process for obtaining them in stoichiometrically pure and virtually non-hygroscopic form.

Abstract: A method and apparatus for automatically and dynamically tuning individual heater segments of a multi-zone furnace which allows simultaneous minimization of temperature gradients within the furnace and prevention of premature aging and failure of the segments by controlling the relative temperatures thereof and equalization of the contributions of the segments to the heating of the furnace. Furnace and heater temperatures are monitored and furnace temperatures are used to develop set point biases for automatic control of heater segment temperatures. Some segments are also controlled as a function of power applied to other segments. Temperatures sensed within the furnace are combined such as by averaging to effectively provide virtual sensors in locations where sensors cannot otherwise be practically provided.

Abstract: A process for preparing cis-dihydronopol and esters thereof in which corresponding esters of (-)nopol are stereoselectively hydrogenated by heterogeneous hydrogenation in the presence of a platinum, platinum oxide or ruthenium/carbon catalyst, and the resulting cis-dihydronopyl esters optionally may be converted into corresponding alcohols by hydrolysis.

Abstract: A method of preparing indole carboxylic acid derivatives from aniline derivatives is described which can be carried out in a single reaction vessel without any isolation of intermediate products. The method involes reacting an aniline derivative with a soluble nitrite in an acid medium, reducing the resulting nitrosamine by treating the acidic nitrosamine containing reaction solution with zinc in the presence of sufficient acid, optionally with addition of additional acid and/or a solvent such as a lower alcohol, reacting the resulting hydrazine derivative containing solution with a lower alkyl ester of pyruvic acid to obtain a corresponding hydrazone which cyclizes to yield an indole carboxylic acid ester, and if desired, hydrolyzing the ester to obtain the corresponding carboxylic acid.