Image Number 13 for United States Patent #8382002.
Improved methods, devices, compositions, and systems are provided for concealing information on articles in commerce, such as pharmaceuticals, to improve detection of counterfeits. Embodiments are provided where Moire patterns on article surfaces are detectable using a revealing layer only when the surfaces are illuminated at or near particular angles. Embodiments incorporating revealing layers into detection systems, such as microscopes, are also provided. A method comprising: providing at least one pharmaceutical composition which comprises at least one surface which comprises at least one area which is adapted to provide a Moire base layer; illuminating the area at an angle; imaging the illuminated area with a Moire revealing layer to generate a Moire pattern. Such embodiments provide an additional layer of security over previous methods of detecting counterfeit articles.