Device for optically scanning sheet-like documents
US5034616A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1990 |
| Grant date | Jul 23, 1991 |
| Priority date | — |
| Expiry date | Mar 14, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07D7/121
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
For automatic recognition of the authenticity of items in sheet form such as bank notes, for example in an automatic service machine, the transparency of each bank note is examined in predetermined spectral ranges. The measuring system is arranged between units of a transport system and, in a passage opening formed from a collector and a diffuser, produces a narrow read-out light beam which extends transversely over a scanning plane. The bank note is conveyed through the read-out light beam, and the light which shines through the bank note in the read-out area is collected in the collector and passed to a photosensitive detector. An evaluation device forms a single measurement value in respect of transparency in the spectral range for each of the successively scanned read-out areas, and compares the measurement values of the bank note being tested with pattern signals stored in a memory of the evaluation device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.