Chemical powder deposition method for the manufacture of optical fiber preforms and optical fibers

• Main Authors: WISK PATRICK WILLIAM, STOCKERT THOMAS EDWARD, YAN MAN FEI, MACCHESNEY JOHN BURNETTE
• Format: Patent
• Language: English
• Published: 25.01.2011
• Subjects: CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUSENAMELS; CHEMISTRY; GLASS; JOINING GLASS TO GLASS OR OTHER MATERIALS; MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES; METALLURGY; MINERAL OR SLAG WOOL; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS,MINERALS OR SLAGS; SURFACE TREATMENT OF GLASS

The specification describes the production of optical fibers and optical fiber preforms using Chemical Powder Deposition (CPD). In this process a slurry of silica powders and dopant powders in a liquid carrier is prepared and the inside surface of a silica glass starter tube is coated with the slurry, then dried. The coating is then consolidated and the tube collapsed as in the conventional MCVD process. Multiple coatings, and coatings with varying compositions, can be used to produce any desired profile. In an alternative embodiment, doped silica glass of the desired final composition is prepared, and then pulverized to form the powder for the slurry. In both embodiments, the use of powders of known composition in the slurry allows direct control over the final glass composition, as compared with conventional processes in which the composition in the final glass is indirectly controlled by control of the thermodynamics of a vapor phase reaction.