Abstract: Apparatus for applying traction to an elongate cylindrical element produced by fusion of an end portion of a preform of glass material, in which a traction device is capable of being connected to a portion of the elongate cylindrical element to provide traction of the elongate cylindrical element along an axis. A device for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element about the axis simultaneously with the traction.

Abstract: Apparatus for applying traction to an elongate cylindrical element produced by fusion of an end portion of a preform of glass material, in which a traction device is capable of being connected to a portion of the elongate cylindrical element to provide traction of the elongate cylindrical element along an axis. A device for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element about the axis simultaneously with the traction.

Abstract: Apparatus for applying traction to an elongate cylindrical element produced by fusion of an end portion of a preform of glass material, in which a traction device is capable of being connected to a portion of the elongate cylindrical element to provide traction of the elongate cylindrical element along an axis. A device for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element about the axis simultaneously with the traction.

Abstract: A process for producing a low-attenuation optical fiber by producing a soot core preform by chemical deposition on a substrate; removing the substrate from the soot core preform, thereby forming a central hole along the soot preform; drying and consolidating the soot core preform in a consolidation furnace to form a glass core preform; heating the glass preform in the consolidation furnace above a glass melting temperature to produce a reduction of the diameter of the central hole; and stretching the glass core preform to completely close the central hole.

Abstract: A process for making a non-zero dispersion shifted optical fiber having low splice loss and low attenuation and to an optical fiber produced by this process. A reduction of the splice loss is observed with decreasing drawing tension. The optical fiber has a core region that includes three segments and an inner cladding segment, each having a maximum refractive index percent difference, ?deltai %, i=0-3, the subscript i referring to a particular refractive index, the core segments being selected such that ?delta0%>?delta2%>?delta1%?0 and ?delta2%>?delta3%?0. Optical fibers exhibiting low splice loss were drawn at tensions not larger than 150 g, preferably not larger than 100 g.

Abstract: A process for producing a low-attenuation optical fiber by producing a soot core preform by chemical deposition on a substrate; removing the substrate from the soot core preform, thereby forming a central hole along the soot preform; drying and consolidating the soot core preform in a consolidation furnace to form a glass core preform; heating the glass preform in the consolidation furnace above a glass melting temperature to produce a reduction of the diameter of the central hole; and stretching the glass core preform to completely close the central hole.

Abstract: A process for making a non-zero dispersion shifted optical fibre having low splice loss and low attenuation and to an optical fibre produced by this process. A reduction of the splice loss is observed with decreasing drawing tension. The optical fibre has a core region that includes three segments and an inner cladding segment, each having a maximum refractive index percent difference, ?deltai %, i=0-3, the subscript i referring to a particular refractive index, the core segments being selected such that ?delta0%>?delta2%>?delta1%?0 and ?delta2%>?delta3%?0. Optical fibres exhibiting low splice loss were drawn at tensions not larger than 150 g, preferably not larger than 100 g.

Abstract: Apparatus for applying traction to an elongate cylindrical element (5) produced by fusion of an end portion (2a) of a preform (2) of glass material, in which a traction device (3) is capable of being connected to a portion (5i) of the elongate cylindrical element (5) to provide traction of the elongate cylindrical element along an axis (6). A device (4) for the rotation of the elongate cylindrical element applies a twist to the elongate cylindrical element (5) about the axis (6) simultaneously with the traction.