The invention proposes a method for determining a rotation angle andor an angular difference in a divided shaft, which has a number of phase tracks disposed on it, which are provided with codes. A secondary transfer unit transfers onto a recording medium the coloring particle image transferred to the intermediate transfer body. \u03b8pp is an angle between two line segments assumed for a pair of flux barriers, each of which connects the center of a rotor core and one of corners of the section of each flux barrier that is closest to the surface of the rotor core.