Long-term behaviour of water vapour absorption in hollow core fibres

We report on the long-term behaviour of water vapour absorption in 19 cell HC-PBGFs in open and spliced conditions. Two main trends were observed as a function of time: increase in absorption of water vapour after opening sealed ends and reduction of the absorption after splicing ends. Furthermore, attenuation at 1550 nm was not significantly influenced by water vapour dynamics at 22 ℃ and 85 ℃.