The present invention relates to a measurement method of the chromatic dispersion of an optical
waveguide using an
optical interferometer with a
broadband multi-
wavelength light source and an optical spectrum analyzing apparatus, wherein one arm, called “reference arm” of the interferometer's two arms has an adjustable air spacing and the other arm, called “sample arm” can contain said optical
waveguide to be measured, and including the following measurement and analysis steps: measuring interference spectra of the
optical beam output exiting from the said interferometer with an optical spectrum analyzing apparatus when said optical
waveguide is connected to said sample arm, and when said optical waveguide is not connected to said sample arm respectively; by adjusting the reference arm length for appearance of clear interference patterns; converting the
wavelength-domain interference spectra into frequency-domain interference spectra and calculating
phase difference values of the interference peaks of one of the spectra from a predetermined reference peak as a function of the frequency change by counting the interference peak (or valley) points; finding a Taylor series curve fit function for each set of the
phase difference value data corresponding to each of the two interference spectra; and calculating a chromatic
dispersion coefficient of the optical waveguide by using the coefficients of the Taylor series curve fit functions.