Patent ID: 6151434
Filing Date: 2000-11-21
Classification: G02B

Abstract:
A cable comprising a leakproof tube containing at least one optical fiber and a filler material which holds the fiber(s) in place inside the tube and which provides longitudinal sealing for the tube,wherein the filling ratio of the fiber-holding material is less than a limit that is determined in such a manner as to leave at least one expansion volume inside the tube so that the partial pressure of hydrogen is low enough to avoid giving rise to significant attenuation in the transmission of properties of the optical fiber(s); andwherein the filling ratio is such that the increase in attenuation of a fiber does not exceed about 0.05 dB/km after accelerated aging, e.g. at 85.degree. C. for seven days, said increase in attenuation being measured at about 1300 nm, 1550 nm, or 1240 nm.