摘要 |
<p>A method for authenticating a document (10). The method includes the steps of: (a) providing a document (10) to be authenticated; (b) illuminating at least a portion (12) of the document with laser light (14) that exceeds a threshold fluence; (c) detecting (16) a narrow band laser-like emission of at least one wavelength from the document in response to the step of illuminating (14); and (d) declaring the document to be authentic only if the laser-like emission is detected.</p> |