Patents Assigned to Quest Automation Public Limited Company
  • Patent number: 4495644
    Abstract: A method for real-time signature verification uses a transducer pad in which the pressure of a stylus causes contact to be made between two resistive films. Such a transducer is energized by current pulses to sample pairs of X and Y coordinates every 5 milliseconds. The analogue voltage outputs are converted to digital form and processed under the control of a microprocessor to determine numerical parameters each representing a significant feature of the signature pattern. A set of specimen signatures is collected and from these the mean values and standard deviations of several relevant parameters are calculated and committed to memory. The parameters for a working signature are compared with the respective stored mean values for the individual concerned. Each deviation from a stored mean value is compared with the corresponding stored standard deviation in a non-linear scoring circuit.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: January 22, 1985
    Assignee: Quest Automation Public Limited Company
    Inventors: John R. Parks, David R. Carr, Peter F. Fox