Angular measurements with X-ray interferometry

The angular dependence of the reflectivity in a skew-symmetric X-ray interferometer with the axis of rotation between two pairs of the reflecting wafers has been investigated experimentally and theoretically. Rapid oscillations with a periodicity of almost 0.002'' have been observed. The period depends on the geometry and the lattice spacing of the interferometer. The amplitudes of the angular oscillations are strongly affected by Pendellösung interference phenomena. As an example of applications an optical autocollimator is calibrated by the X-ray interferometer.