the tag has a rainbow like feature that will reflect different wavelengths of light energy contained within the white light at different angles this will yield a colorful reflectance pattern with no apparent directionality however when the tag is illuminated from a single specific angle and a single specific wavelength then the reflectance characteristics will yield an image that will look like that shown in fig6 c the image shown in fig6 c can then be easily detected by a cmos or ccd linear or area image sensor the output signals from the imager 64 can then feed a microcontroller 80 that will interrogate the pattern and determine if the optical characteristics of the tag is valid or a counterfeit the cross section of a tag embodying the invention is shown in fig2 and 4 the top layer 35 may be a hri material that has specific optical characteristics and patterns that will be used in the detection scheme layer 35 may also be any material that has similar reflectance characteristics to those of the hri material the backing of the hri layer is an adhesive layer 33 that can have additional optical characteristics for example the material comprising layer 33 may be designed to absorb most of the ir illumination this will produce the necessary optical contrast that is required for detection of the hri.