| 摘要 |
The innovation involves the use of a laser to ablate a calculated microstructure or employ an adaptation of maskless photolithography using a Digital Micromirror Device to serve as a Spatial Light Modulator to embed a covert diffraction screen, holding encrypted information under transparent surfaces of plastics or glass substrates. One method includes the steps of fragmenting the calculated diffraction screen into at least first and second parts that are placed in separate locations. In this method the binary pattern in each of the parts includes information representing a respective portion of the original image and needs to be interrogated simultaneously to provide a meaningful visual output: each part by itself being incapable of generating any meaningful information. The fragmentation method allows a public-private key type of secure system platform.
|
