Patent · US Expired

Method for determining quality of U.S. currency

US4255057A · kind A · utility

32Cited by
3References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 4, 1979
Grant dateMar 10, 1981
Priority date
Expiry dateOct 4, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07D7/12
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

An apparatus for detecting quality of currency or the like. Signals representative of the transmissivity and reflectivity of a bill are subtracted from a signal representative of unity. The resulting signal, which is representative of absorptivity of light by the bill, is accumulated over the length of the bill and compared to a reference to produce digital signals representative of fit or unfit bills.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.