1. An optoelectronic angle sensor for determining a rotational angle about an axis, comprising: a circular disc rotatable about the axis and having a coding substantially over the whole area; a planar photosensitive detector, the circular disc and the detector being moveable relative to one another; a device for producing an evaluable image of the coding on the detector in such a way that the evaluable image comprises information about the relative position of circular disc and detector; and a memory and evaluation component for determining the rotational angle, wherein: the device produces a substantially complete image of the coding and the memory and evaluation component; provides a configured electronic reference pattern which can be coordinated with the coding; and determines the rotational angle from said reference pattern and said substantially complete image by means of a parameter-varying stochastic comparison method.