US Patent 9582954 Article vending machine and method for authenticating received articles

An article dispensing machine, system and method for authenticating an article returned to the article dispensing machine and an article for use in such a machine and system are disclosed herein. The returned article comprises an authentication code disposed on the surface of the returned article and a layer that is substantially opaque in visible light and at least partially overlays the authentication code. The article dispensing machine comprises a light source for illuminating the surface of the returned article so that the authentication code is visible through the layer, an image capture device for capturing an image of the authentication code when the surface is illuminated, and a processor for comparing the captured image to a master authentication code.