Patent ID: 6605819
Filing Date: 2003-08-12
Classification: G07D

Abstract:
A method of validating selected properties of media, the method comprising the steps of:(a) providing a sensor apparatus comprising a plurality of distinct monochromatic light sources extending radially inwardly from a perimeter of a disc toward a common light detector which is positioned at a center of said disk to receive only diffusely reflected light from the sources; (b) locating an item of media in a path of the sensor apparatus; (c) activating a first monochromatic light source, and detecting light diffusely reflected from the media, to provide an output from the detector containing data relating to the response of the media to the light source; (d) moving the media with respect to the sensor apparatus; (e) activating another monochromatic light source, and detecting light diffusely reflected from the media, to provide an output from the detector containing data relating to the response of the media to the light source; (f) repeating steps (d) and (e) at least until each distinct monociromatic light source has been activated; (g) processing the sample data to determine a selected characteristic of the media; and (h) comparing the sample data against a reference database of data obtained from genuine media.