Abstract:
To improve a generally known method for producing a tubular semifinished product from fluorine-doped quartz glass such that it is possible to produce a tubular semifinished product of fluorine-doped quartz glass with an inner bore of high quality while the efforts for making or treating the same are as small as possible, the present invention suggests a method comprising the following steps: (a) providing a substrate tube consisting of fluorine-doped quartz glass; (b) forming, in a deposition process, SiO 2 particles by means of plasma burners and in the presence of fluorine, and depositing said particles in layers on the cylindrical outer surface of the substrate tube rotating about its longitudinal axis with formation of a mother tube consisting of fluorine-doped quartz glass; and (c) elongating the mother tube in an elongation process to obtain the tubular semifinished product.
Abstract:
The present invention relates to a method for depositing one or more glass on the external surface of a rod-like glass preform, which method comprises the steps of: i) placing the preform in an enclosed space, ii) creating a sub-atmospheric pressure in said enclosed space, iii) supplying one or more reactive gases, which may or may not be doped, to the enclosed space, iv) generating a plasma zone in said enclosed space, and v) carrying out a deposition reaction.
Abstract:
Um ein allgemein bekanntes Verfahren zur Herstellung von fluordotiertem Quarzglas, bei dem mittels eines Plasma-Abscheideprozesses SiO 2 -Partikel in Gegenwart von Fluor gebildet und schichtweise auf einem Aussenmantel eines um seine Längsachse rotierenden, zylinderförmigen Substratkörpers aus Quarzglas abgeschieden und zu einer Schicht aus Quarzglas mit einem Fluorgehalt von mindestens 1,5 Gew.-% verglast werden, dahingehend zu verbessern, dass ein Halbzeug aus Quarzglas mit hohem Fluorgehalt erhalten wird, das sich durch eine hohe Grundtransmission im UV-Wellenlängenbereich auszeichnet, wird erfindungsgemäß vorgeschlagen, dass der Substratkörper mindestens im Bereich des Aussenmantels eine Reservoirschicht aus Quarzglas aufweist, das einen Hydroxylgruppengehalt von 200 Gew.-ppm oder mehr und/oder einen Wasserstoffgehalt von 1 x 10 17 Molekülen/cm 3 oder mehr aufweist, und dass der Substratkörper nach dem Abscheiden der mit Fluor dotierten Quarzglasschicht entweder vollständig oder teilweise entfernt wird.
Abstract translation:用于生产掺氟的石英玻璃,其中通过等离子体沉积过程中,在氟的存在SiO 2颗粒形成,并沉积在层上的一个绕其纵轴旋转的圆柱形衬底本体由石英玻璃制成的外护套以及具有一个石英玻璃的层上的公知的工艺 氟含量被玻璃化的至少1.5重量%,以提高其由石英玻璃制成的半成品与高的氟含量,其特点是在UV波长范围内具有高的基本传输所获得的效果,本发明提出的是,基体至少在该区域 具有按重量计或更多和/或1×10 17分子/ cm 3以上,并且的氢含量为200 ppm的羟基含量的石英玻璃构成的贮库层外壳掺氟的石英玻璃层的沉积要么完全后的基板构件 是或部分地去除。
Abstract:
In a known process for the manufacture of a preform for optical fibres of quartz glass using a plasma burner (1), this is operated in a deposition phase and a smoothing phase, a silicon-containing starting substance being supplied to the plasma burner during the deposition phase, SiO 2 being formed therefrom in a plasma flame allocated to the plasma burner and this SiO 2 being deposited in layers on the cylinder jacket surface (9) of a substrate body (3) rotating around its own longitudinal axis by reversing movement of the plasma burner along the substrate body and being vitrified directly during this process into quartz glass of the preform and the preform surface being treated during the smoothing phase, by the plasma flame moving at least once along the preform, with a temperature which is higher in comparison with deposition phase such that smoothing of the preform surface and melting of the near-surface bubbles are effected. In order to indicate an economic process on this basis which allows the manufacture of low bubble content or bubble-free preforms with an acceptable time and material expenditure, it is suggested according to the invention that the deposition phase comprises a multiplicity of successive deposition sub-phases in the course of which a quartz glass layer is produced in a thickness of less than 400 µm, successive deposition sub-phases being interrupted by a smoothing phase.
Abstract:
In a known method for the production of a blank mold for optical fibers, a fluorine-doped Si02 enveloping glass is produced on a core glass cylinder that rotates about its longitudinal axis, wherein a silicon-containing starting substance is fed to a plasma burner, said substance is then oxidized in a plasma flame assigned to the plasma burner to obtain Si02 particles, the Si02 particles are deposited by layers on the enveloping surface of the cylinder of the core glass cylinder in the presence of fluorine and sintered into the enveloping glass. The invention aims at providing an economical method, which builds upon the above-mentioned method, in order to produce a blank mold from which optical multi-mode fibers (52) can be obtained. In comparison with fibers (51) produced according to standard methods, said optical multi-mode fibers are characterized by high initial transmission in the UV wavelength range and good resistance with respect to brief UV radiation, more particularly in the 210-300 nm wavelength range. According to the invention, a plasma flame that irradiates an ultraviolet light having a wavelength of 214 nm with an intensity of at least 0.9 ñW -determined on the basis of plasma flame intensity measurement- is used for the formation and deposition of the Si02 particles on the core glass.
Abstract:
A plasma torch (40) deposits silica on a target rod (30). The torch (40) traverses along the lathe (24) multiple times, so as to build up the preform (34).
Abstract:
The plasma torch (40) for making synthetic silica includes use of nitrogen screen gas from outer quartz tubing (53) to provide active environment isolation. In addition, the present induction plasma torch (40) includes ring disks (66, 70) for more compact but complete environmental protection (360 degree coverage) . It also includes offsetting and switching the position of the chemical injection nozzles (68) for allowing improved deposition in both directions, when operated in a horizontal mode. Further, the present induction plasma torch (40) maintains laminar flow for the injected chemicals and the middle quartz tube (154) is provided with a concave section (157) for increasing the average enthalpy of plasma jet, thus improving the efficiency of the plasma torch. In addition, it may utilize more plasma gas inlets (76) . It also includes chemical injection nozzles (68) having a downward angular inclination.
Abstract:
In a known process for the manufacture of a preform for optical fibres of quartz glass using a plasma burner, this is operated in a deposition phase and a smoothing phase, a silicon-containing starting substance being supplied to the plasma burner during the deposition phase, SiO 2 being formed therefrom in a plasma flame allocated to the plasma burner and this SiO 2 being deposited in layers on the cylinder jacket surface of a substrate body rotating around its own longitudinal axis by reversing movement of the plasma burner along the substrate body and being vitrified directly during this process into quartz glass of the preform and the preform surface being treated during the smoothing phase, by the plasma flame moving at least once along the preform, with a temperature which is higher in comparison with deposition phase such that smoothing of the preform surface and melting of the near-surface bubbles are effected. In order to indicate an economic process on this basis which allows the manufacture of low bubble content or bubble-free preforms with an acceptable time and material expenditure, it is suggested according to the invention that the deposition phase comprises a multiplicity of successive deposition sub-phases in the course of which a quartz glass layer is produced in a thickness of less than 400 µm, successive deposition sub-phases being interrupted by a smoothing phase.