| 摘要 |
<p>A system for authenticating and discriminating currency utilizes an ultraviolet light source to illuminate a document to be tested and an ultraviolet light detector (902) to detect the ultraviolet light reflected by the document. An output signal (924) proportional to the reflected ultraviolet light is provided from the ultraviolet light detector (902) to a signal processor (912), which determines the authenticity of the document based upon the output signal (924). The document is considered genuine if the output signal (924) is within a predetermined range of the expected value. In another embodiment, the system includes an ultraviolet light source to illuminate a document to be tested and both an ultraviolet light detector (902) and a visible light detector (904). The visible light detector (904) detects and provides an output signal (922) proportional to the visible light emitted by the document. The signal processor (912) receives both the ultraviolet light detector and visible light detector output signals (924, 922) and determines the authenticity of the document based upon the reflected ultraviolet light and detected visible light. The document is considered genuine if the output signal (924) is within a predetermined range of the expected value and if the amount of visible light does not exceed a visible threshold.</p> |
