Apparatus for authenticating sheets
US6094500A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1998 |
| Grant date | Jul 25, 2000 |
| Priority date | — |
| Expiry date | Feb 13, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07D7/1205
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A self-service deposit terminal (10) is arranged to authenticate bank notes by exposing them to ultra-violet (UV) light which causes forged notes comprising wood-based paper to fluoresce. Each note (36) is individually transported between a UV light tube (38) and a first photo-diode (40). The level of light emitted by the UV light tube is monitored by a second photo-diode (52). The amplified output of this second photo-diode acts as a threshold value. The amplified outputs of both photo-diodes are applied to a Schmitt trigger (60) which outputs a high signal if the tested note is judged to fluoresce and a low signal if it does not. The output of the Schmitt trigger (60) is applied to a data processing means (24) which determines either solely on this output, or in conjunction with the output from other validation means, whether the tested note is genuine or not.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.