Measurement of fiber parameters of pure silica core fibers based on the OTDR technique.

We propose a simple technique based on optical time domain reflectometry (OTDR) for measuring the cutoff wavelength and core radius distributions in a pure silica core fiber for the first time. The proposed technique can simultaneously measure several important fiber parameters such as the mode field diameter, relative-index difference, effective area, and chromatic dispersion, including the cutoff wavelength and core radius. We experimentally demonstrate that our proposed technique can successfully evaluate these fiber parameter distributions and can be applied for the measurements of few-mode and multi-core fibers with pure silica cores using multi-channel OTDR and mode couplers.