Abstract: The invention relates to a method for detecting optical errors, especially in refractive power, in large surface panels made of transparent material such as glass, by evaluating an observed image. The steps of the inventive method include: projection of a defined model consisting of regular sequences, whereby the sequences includes two varying light intensities and arrangement of the panel in the optical path of projection. The inventive method enables detection of optical errors in at least one dimension of a panel without a reference screen by projecting the model onto a camera, whereby a model sequence is respectively represented on a certain number of adjacent camera pixels and the number is an integral multiple of the sequence.