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: 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: 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: The invention relates to a thin-layer chromatography apparatus (1) having a plurality of optical light guides to inject light from a light source (2) onto a thin-layer plate (4) and to feed light from the thin-layer plate to an optical examining device (6). To obtain a robust, compact thin-layer chromatography apparatus having a high spectral and spatial resolution, with which there are only minimal disturbances, if any, caused by ambient light and which is nonetheless economical to produce, the invention provides for the emitted-light guides (3) and or received-light guides (5) to be positioned in a regular geometrical pattern in relation to each other either towards or away from the plate, as represented by the rows (11 and 14). The light spots emitted by the emitted-light guides and the field of vision of the received-light guide overlap in an adjustable manner (linear movements 12b, pivoting movements 12a), as regards spatial resolution and light yield.

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 multimode optical fiber for UV light transmission, able to be sterilized with gamma radiation, has a core including undoped synthetic silica, a cladding including fluorine doped synthetic silica, a hydrogen content higher than 5.times.10.sup.19 molecules/cm.sup.3 and a metal coating that retards diffusion of hydrogen outwardly from the fiber, the metal being selected from aluminum, copper, zinc, tin, silver and gold. The metal coating has a high diffusion coefficient below 150.degree. and a low diffusion coefficient at a hydrogen loading temperature above 250.degree. C. The optical fiber may have a high-OH content of 50 to 1500 ppm and a low-OH content below 50 ppm after treatment. The optical fiber may also or alternatively have a low-OH content below 50 ppm, and preferably below 5 ppm, before treatment. A gamma radiation sterilized multimode fiber bundle may include a plurality of such optical fibers. A gamma radiation sterilized catheter may include at least one optical fiber or a fiber bundle.

Abstract: Disclosed is a method for the axial building up, in a vertical arrangement, of a hollow cylindrical soot body having no internal support and consisting substantially of silicon dioxide by means of at least one flame hydrolysis build-up burner serving for the soot production. In this method the soot is deposited at the beginning of the build-up onto an auxiliary body, and during the build-up the build-up burner and the growing soot body are rotated relative to one another, and the burner is at the same time held at an unvarying distance from the growing end of the hollow cylinder and centrally above the predetermined cross section of the upwardly growing end of the cylinder wall. The penetration of soot into the interior of the cylinder is prevented by means of a directed gas stream.