1. A method for checking the usage state of a document of value comprising the steps: illuminating the document of value with illumination light, taking an image of the document of value by detecting light intensities of the light reflected from the illuminated document of value, choosing an image detail of the taken image in which an opaque, reflective section of the document of value is imaged, the opaque, reflective section being at least a partial area of an opaque, reflective foil element of the document of value, examining the chosen image detail for signs of creases which may possibly be present in the opaque, reflective section of the document of value, and using a result of the examining for judging the usage state of the document of value.