Dispersion of group and phase modal birefringence in elliptical-core fiber measured by white-light spectral interferometry

We present a white-light spectral interferometric technique employing a low-resolution spectrometer for measurement of the dispersion of the group and phase modal birefringence in an elliptical-core optical fiber over a wide spectral range. The technique utilizes a tandem configuration of a Michelson interferometer and the optical fiber to record a series of spectral interferograms and to measure the equalization wavelengths as a function of the optical path difference in the Michelson interferometer, or equivalently, the wavelength dependence of the group modal birefringence in the optical fiber. Applying a polynomial fit to the measured data, the wavelength dependence of the phase modal birefringence can also be determined. (C) 2003 Optical Society of America.