Ultraviolet absorption due to a GeO2 defect of a GeO2/SlO2 core optical waveguide is well known. It is reported that there are some kinds of UV absorption due to the GeO2 defect and that one of them is impossible to reduce because of its intrinsic property.1 Recently, however, an UV-absorption-free high-N.A. liber with a GeO2 additive was developed by using fluorine-added silica as the cladding in the VAD process. The UV absorption behavior of a GeO2/SiO2 core optical waveguide is discussed.
© 1987 Optical Society of AmericaPDF Article