Loss distribution measurement of silica-based waveguidesby using a jaggedness-free optical low coherence reflectometer

Abstract
The loss distributions in silica-based waveguides are successfully measured using a jaggedness-free optical low coherence reflectometer (OLCR). The OLCR reduces the unavoidable jagged fluctuations which appear in Rayleigh backscattering measurements undertaken with conventional OLCRs to within ± 1 dB by averaging the wavelength-dependent Rayleigh backscatter signals. Constant loss distributions and a step-like loss increase in the waveguides were clearly observed.