Measurement of the phase dispersion of optical components by heterodyne interferometry

Abstract We describe the use of a heterodyne Michelson interferometer to measure the wavelength-dependent phase shift of a Gires-Tournois interferometer. A comparison of the experimental and the calculated phase characteristics reveals significant deviations indicating, in particular, a different group velocity dispersion of the device under test. The results show that the heterodyne interferometer in combination with a tunable laser is well suited for the measurement of the phase characteristics of optical components.