Process for identifying an embossed image of a coin in an automatice coin machine

摘要

To identify an embossed image of a coin in an automatic coin machine, the coin requiring identification is moved past an image receiver and a light source, the light source having at least two lighting portions which illuminate an object field of the coin requiring identification from different directions under the same angle with respect to the surface normal of the object field and with wavelength ranges which do not overlap each other. An image receiver records one picked-up exposure of the object field from which images are obtained for each of the individual lighting portions of the individual wavelength ranges. A maximum image is then determined from the images, wherein each pixel has associated therewith the maximal intensity value from the images of the individual wavelength ranges. A genuine-coin or counterfeit-coin signal is determined from the maximum image.