Options
1990
Conference Paper
Titel
Radiation damage and radiation induced loss in optical fibres
Abstract
The radiation induced loss in optical fibres is initially determined by the preform properties, the fibre draw conditions, and the radiation test parameters. We have found that some fibres change their radiation sensitivity considerably after exposure to high dose values (100000-1000000 rd) and explain this with radiation damage, i.e. the production of new precursors for colour centres in concentrations comparable or even higher than those of the initial ones. To get further informations about the nature of eventually generated new defects, we compared the transient induced loss of damaged and undamaged fibres as well as measured the wavelength dependence of the induced loss with increasing 60Co gamma dose. Some fibres (polymer fibres and OH rich fibres with pure SiO2 core) showed considerable permanent damage, whereas Ge doped fibres (single mode as well as graded index) remained nearly unchanged up to 1000000 rd.