OPTICAL-FIBER RING-RESONATOR CHARACTERIZATION BY OPTICAL TIME-DOMAIN REFLECTOMETRY

A novel method for characterization of optical fiber resonators by an optical time-domain reflectometry (OTDR) technique is reported. This e asy-to-use technique yields accurate results for cavity lengths rangin g from a few meters to several kilometers. A simple relationship is es tablished between the round-trip cavity loss and the position where th e OTDR signal is maximum. The value obtained for the round-trip cavity loss turns out to be quite insensitive to uncertainties in the determ ination of the OTDR maximum position. (C) 1997 Optical Society of Amer ica