Automatic gain control for photosensing devices
Method for determining quality of U.S. currency
Method for detecting physical anomalies of U.S. currency
Control circuit for bill and coin changer
Method and apparatus for testing the ends of cigarettes or the like
Apparatus for sorting sheets according to their patterns Patent #: 4542829
ApplicationNo. 06/494857 filed on 05/16/1983
US Classes:356/71, DOCUMENT PATTERN ANALYSIS OR VERIFICATION209/534, Sorting paper money250/556, Document verification or graph reader356/435, With plural detectors (e.g., simultaneous viewing)356/73PLURAL TEST
ExaminersPrimary: McGraw, Vincent P.
Assistant: Thompson, III, Robert D. V.
Attorney, Agent or Firm
International ClassesG07D 7/12 (20060101)
G07D 7/00 (20060101)
AbstractAn improved universal document validator in which a document is transported along a path past light detectors and associated light sources positioned above and below the path, such that light from the sources is directed toward the path and reflected onto the detectors to produce outputs therefrom. A first stored value representing the desired output of each detector with no document in the transport path and with its associated light source illuminated is divided by the actual output of each detector with no document in the transport path and with its associated light source illuminated, to produce a plurality of quotients. If any of the quotients falls outside a predetermined range, the validator turns itself off. A microprocessor control system uses the outputs of the detectors with a document in the transport path together with the quotients to produce an indication of the validity of the document.