That part of attenuation in optical fibers that is caused by the transformation of optical energy into heat. Expressed in dB/km.
(1) The amount of moisture a given substance will assimilate and retain. An important property consideration in the selection of insulating materials. (2) Loss of power in an optical fiber, resulting from conversion of optical power into heat and caused principally by impurities, such as transition metals and hydroxyl ions, and also by exposure to nuclear radiation.
A physical mechanism in fibers that attenuates light by converting it into heatâ€”thereby raising the fiberâ€™s temperature. In practice the temperature increase is slight and difficult to measure. Absorption arises from tails of the ultraviolet and infrared absorption bands, from impurities such as the OH - ion, and from defects in the glass structure.