Single mode fibre optic cable index profiling construction; has V-shaped core profile index with outer core index rising above constant level outer sleeve index

摘要

The fibre optic cable construction has an outer sleeve section with a first index level (n3), and a central core section with a lower central index (n2) rising above the surrounding sleeve at the edges (n1). The central core index profile is V-shaped from the central low value to the higher outer value.