Subthreshold flaws and their failure prediction in long-distance optical fiber cables

Abstract

Absfract-A study of surface defei i s and static fatigue data support the view that subthreshold surface defects are responsible for failure in prooftested optical fibers. For this type of defect, crack initiation, as opposed to crack growth, is the rate limiting step. Classical crack propagation theory does not dewribe this process sufficiently well for lifetime prediction, but semi-empirical techniques indicate that this popular treatment may be pessimistic. A more conventional reliability treatment, similar to that employed for other system components, appears to offer the best available approach to the task of failure lifetime prediction in prooftested fibers.

Design Considerations in Reduced-Diameter Single-Mode Optical Fibers

“…A considerable amount of information is available for in-line proof testing of 125-Jlm optical fiber (see, for example, Camilo and Matthewson, 16 Donaghy and Dabbs, 17 and Camilo 18 ). Tensile proof testing is the preferred method over two-point bend testing because the latter method stresses a very small area of fiber.…”