A simple dispersion measurement of fiber gratings by interferometric technique

Abstract

A simple dispersion measurement of fiber gratings using an un-balanced Michelson interferometer is proposed. A broadband source and an optical spectrum analyzer are used to scan the interference spectrum, and then the group time delay can be obtained rapidly by Fourier transform processing the interference spectrum. We measured the group time delays of a uniform-period FBG, a chirped FBG, an arrayed-waveguide grating interleaver, and a thin-film filter type OADM by an un-balanced Michelson and Mach-Zehnder interferometers, respectively. The experimental results excellent match the measured results of the optical network analyzer. The experimental repeatability is shown to be better than 1ps.