Single mode optical transmission fiber, and method of making the fiber

摘要

The transmission fibre has a core of diameter d, a deposited cladding of diameter D contactingly surrounding the core, and a tube-derived cladding contactingly surrounding the deposited cladding. The tube-derived cladding contains hydrogen getter sites selected to prevent migration of hydrogen into the deposited cladding during manufacture of the fibre, and D and d are selected such D/d 2.5. The tube-derived cladding is derived from a substrate tube that contains hydrogen getter sites is effective for reducing, at a processing temp, the rate of hydrogen migration through the substrate tube wall by at least 50% as compared to the rate of hydrogen migration at the processing temp through the wall of an otherwise identical comparison tube that does not contain hydrogen getter sites. The hydrogen getter sites comprise an element selected from the group consisting of Ge and P.