Abstract

It is essential to suppress the optical absorption at around 630 nm to develop radiation-resistant image-guide fibers. This absorption is called the 2 eV absorption in this report. This report shows even pure-silica core fibers, which are known to have good radiation resistance, show relatively large 2 eV absorption if the cladding material is doped glass. The cause of the absorption and the method to suppress it are also discussed.

© 1986 Optical Society of America