optical fiber preform manufacturing technologies patents

He also explains root causes of impurities in the manufacturing process of the raw materials and why they can’t be eliminated in later production steps.įinally, he explains how tube geometry determine the fiber performance, another main influencing factor. How particles influence the mechanical strength of the fiber and breakage rate in the fiber drawing process. How contaminations effect the attenuation and transmission performance. Bauer presents influencing factors of these processes on purity and geometry.įurthermore, he provides essential background on impurities and how they influence the fiber performance.

Peter Bauer of Heraeus Conamic is going to give some insights in manufacturing processes for fused silica tubes.

The performance of optical fibers is highly sensitive on the manufacturing process and raw materials used. Optical fibers made of fused silica have many applications in communication, sensing and laser systems.

Products for Semiconductor Applications.

Material Processing & Industrial Applications.

After the liquid reactant has cleared the system, flow of the evaporative liquid is terminated and the burner assembly flame turned off. Once the desired quantity of soot has been formed, the liquid reactant is transitioned back to the evaporative liquid while maintaining steady state flow. The liquid reactant is delivered along the same path to the burner assembly, which discharges the liquid reactant into the combustion zone as an atomized liquid to form soot used in the manufacture of glass. Once steady state liquid flow has been achieved in the system, the evaporative liquid is transitioned to the liquid reactant. Due to the tendency of liquid reactants to react to form solids when exposed to water in the air, an evaporative liquid is first delivered through the burner assembly to the combustion zone. The drive-in step is conveniently combined with the sintering or consolidation step to further enhance the efficiency of the doping process.Ībstract: The present invention is directed to a system and method for delivering liquid reactants through a burner assembly to form soot used in the manufacture of glass, and in particular, optical waveguides. In the incremental doping process the doping step is separated into a deposit step, where “excess” fluorine is deposited on the silica particles, and a drive-in step where atomic fluorine is distributed into the silica particles. The process time required may be reduced by using incremental fluorine doping. This inherent property allows the entire core rod to be heated prior to fluorine doping resulting in selective partial consolidation and preventing fluorine doping of the doped center core region. Due to dopants in the core region, the soot in the core region consolidates before the soot in the outer undoped region. When a 50 percent substitution of oxygen -18 for oxygen-16 is made in the core region of the fiber, the Raman gain spectrum is substantially broadened.Ībstract: The doped silica core region of a core rod for an optical fiber preform is protected against unwanted fluorine doping during fluorine doping of the outer silica layer by selectively consolidating the core region prior to fluorine doping. The fiber may be easily manufactured with conventional fiber manufacturing equipment by way of a plasma chemical vapor deposition technique. The resulting isotopically-altered fiber has a minimum loss of 0.044 dB/km less than conventional fiber, and a bandwidth that is 17 percent broader for a loss range between 0.044-0.034 dB/km. In one embodiment, oxygen-18 is substituted for the much more naturally abundant oxygen-16 at least in the core region of the fiber. A heavier, less naturally abundant isotope of silicon or oxygen is substituted for a lighter, more naturally abundant isotope to shift the infrared absorption to a slightly longer wavelength. Abstract: An isotopically-altered, silica based optical fiber is provided having lower losses, broader bandwidth, and broader Raman gain spectrum characteristics than conventional silica-based fiber.

Optical fiber preform manufacturing technologies patents