Absolute phase birefringence dispersion in polarization-maintaining fiber or birefringent crystal retrieved from a channeled spectrum

摘要

We report on a simple method for retrieving the wavelength dependence of the phase birefringence in anpolarization-maintaining fiber or a birefringent crystal from a channeled spectrum. The method utilizes in-nterference of polarized modes or waves resolved as the channeled spectrum and its processing by a windowednFourier transform to reconstruct precisely the phase as a function of wavelength. The ambiguity of the phasenis removed provided that we know both the approximative function for the birefringence dispersion and thenlength of the fiber or the thickness of the crystal. The method is used in measuring the wavelength depen-ndence of the phase birefringence in an elliptical-core fiber or in a quartz crystal in a range fromn500 to 900 nm. The dependences are compared with those resulting from the available data, and very goodnagreement is confirmed. © 2010 Optical Society of America