Hydroxyl ion absorption is the
absorption in
optical fibres of
electromagnetic waves, including the near-
infrared, due to the presence of trapped
hydroxyl ions remaining from water as a contaminant.
The hydroxyl (OH-) ion can penetrate glass during or after product fabrication, resulting in significant attenuation of discrete optical wavelengths, e.g. , centred at 1.383 μm, used for communications via optical fibres.
See also
Water absorption