Detecting luminescent security features
US4650320A · kind A · utility
38Cited by
13References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1984 |
| Grant date | Mar 17, 1987 |
| Priority date | — |
| Expiry date | Apr 27, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07D7/20
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Luminescent security features in or on documents are detected using a detector comprising a fibre optic light guide arranged to transmit an interrogation beam originating from a source onto a document to be tested; and a housing in which a photo-diode array is mounted to receive luminescence emitted from the document. The photo-diode array is connected to electronic circuitry for discriminating between luminescence due to a security feature and other luminescence emitted by the document and for determining that a security feature has been detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.