Authenticating system

摘要

An authenticating system for verifying articles is provided. The articles to be verified have a thin film multilayer coating applied to them that serves or functions as a type of finger print. In a reflective mode of operation the coating is designed to reflect light radiation of predetermined wavelengths and substantially absorbing or transmitting light radiation of other predetermined wavelengths irradiating a same location on the coating surface; in operation a light source is provided for irradiating light onto said location on the coating surface; and a detector is used to determine the presence and absence within predetermined limits of each of said predetermined wavelengths of light at said location that are substantially reflected by the coating. The system may also be configured in a transmissive mode or an absorptive mode of operation when used with the compatible detection schemes as exemplified herein.