초록 ▼

An authentication system combines a source of ultraviolet light (and optionally a scanning mechanism) with apparatus for capturing and recognizing either graphic images or characters or both, where the graphic images and/or characters have been previously made with fluorescent substances that may be

An authentication system combines a source of ultraviolet light (and optionally a scanning mechanism) with apparatus for capturing and recognizing either graphic images or characters or both, where the graphic images and/or characters have been previously made with fluorescent substances that may be invisible under ordinary visible light, but are rendered detectable by the ultraviolet light. As in conventional optical character recognition (OCR), the characters may be conventional alphanumeric characters readable by human readers once they are made visible. The authentication system has a housing enclosing its optical path, a source of UV light, a detector for detecting graphic images or characters, conversion of the detector signal to digital form, a memory storing predetermined indicia, recognition logic, and indicating means. The system may also include a scanning mechanism and optical filters to select predetermined wavelengths of fluorescent light. The detector may be capable of detecting both fluorescent images and normal visible images, and the authentication system may incorporate switching mechanisms to allow multiplexed acquisition of fluorescent and normally visible images. The authentication system can operate in conjunction with a process for marking articles with indicia selected from a predetermined set of graphic images and characters readable by optical character recognition and/or by image comparison. That process can include printing fluorescent graphic images or characters in registration with (or with predetermined offset from) visible images or characters or indicia printed with substances fluorescent at different wavelengths. The recognition logic of the authentication system can include comparison of fluorescent and visible images or two different fluorescent images with each other. Pairs of indicia to be recognized and/or compared may be arranged to constitute a stereogram or other arrangement for first-order authentication by a human observer.

대표청구항 ▼

[ Having described my invention, I claim:] [1.] A process for marking articles for authentication, comprising the steps of:a) providing one or more predetermined fluorescent substances,b) providing a transparent non-fluorescent carrier medium in which said fluorescent substances are miscible,c) mixi

[ Having described my invention, I claim:] [1.] A process for marking articles for authentication, comprising the steps of:a) providing one or more predetermined fluorescent substances,b) providing a transparent non-fluorescent carrier medium in which said fluorescent substances are miscible,c) mixing said fluorescent substances in predetermined concentrations in said carrier medium,d) selecting indicia from a predetermined set of characters and graphic images readable by optical character recognition means and image comparison means respectively, ande) printing said selected indicia on said articles with said carrier medium containing said predetermined concentrations of said fluorescent substances, said selected indicia being printed in predetermined offset from registration with indicia previously printed on said article, and said predetermined offset being chosen such that said selected indicia and said previously printed indicia in combination form a stereogram when viewed from a standard near-point reading distance of 25 centimeters.