| 摘要 |
Preforms for optical waveguides have previously been manufactured with considerable expenditure of time and gas for the drying, because the OH content is critical for the quality of the end product with regard to attenuation. The aim of the invention, therefore, was to modify the known process, starting from the OVD method, with substantially reduced complexity. The MOVD modification consists in passing a drying-gas mixture under overpressure from inside to outside through the tubular growth of porous deposit arising from the combustion of the hydrolytic gas mixture, already during the growth of the porous deposit and preferably for some time after that. Besides reducing complexity, this also marks a qualitative advantage of the process in the decreasing concentration of OH ions from outside to inside. Manufacture of optical waveguides. |
